Acta Geologica Polonica, Vol. 48 (1998), No.2, pp. 157-236
Upper Cretaceous of the Barranca (Navarra, northern Spain); integrated litho-, bio- and event stratigraphy. Part I: Cenomanian through Santonian
THOMAS KUCHLER
Institutfiir Geologie und Paliiontologie, Freie Universitat Berlin, Haus D, Malteserstr. 741IOO, D-12249 Berlin, Germany. E-mail: [email protected]
ABSTRACT:
KUCHLER, T. 1998. Upper Cretaceous of the Barranca (Navarra, northern Spain); integrated 1itho-, bio and event stratigraphy. Part I: Cenomanian through Santonian. Acta Geologica Polonica, 48 (2), 157-236. Warszawa.
Fossiliferous Upper Cenomanian to Lower Maastrichtian strata in Navarra, northern Spain, particularly in the eastern Barranca, were investigated in terms of lithostratigraphy, macrofossil biostratigraphy and event stratigraphy. Extensive bed-by bed-collections of ammonites, inoceramids, and echinoids allow the estab lishment of combined standard zonal schemes of inter-regional significance. Data on geochronological boundaries, macrofossil distribution, the succession of events and the inter-relations between bioevents, eustato-events and tectonic movements in northern Spain are presented. The Upper Cenomanian - Turonian successions of the Barranca sections (Arardi, Izurdiaga, Satrustegui) and of the Estella area (Ganuza, Ollogoyen), differ considerably in both lithofacies and thickness and, peri odically, in faunal composition, as a result of their palaeogeographical positions within an stable outer shelf and an unstable mid-shelf, respectively. The Ganuza/Ollogoyen standard section is revised. In the context of the established event stratigraphical scheme, discrepancies in previously applied ammonite zonation are pointed out and discussed in terms of their regional relevance. The expanded and relatively complete Turonian of the Estella area is subdivided into an unnamed interval devoid of ammonites (Upper Cenomanian Metoicoceras geslinianum Zone to the mid-Lower Turonian), six ammonite zones and an inoceramid/ammonite assemblage zone. The upper Lower Turonian Kamerunoceras ganuzai/Mammites nodosoides Zone is succeeded by the Middle Turonian zones of K. turoniense, Romaniceras kallesi, R. ornatissimum and R. deverianum; and the Upper Turonian Subprionocyclus neptuni and Cremnoceramus ~valtersdO/fensis/ Prionocyclus germari zones. The Lower Turonian zonal scheme given by WIEDMANN (1979a) for the Estella area is shown to be impracticable, and neither Lower Turonian Choffaticeras quaasi Zone sensu SANTAMARIA (1992) nor a Watinoceras coloradoense Zone sensu LAMOLDA & al. (1989) can be recognized. On the other hand, the refined French Middle Turonian ammonite zonation of AMEDRO & al. (1982) is readily applicable, while the application of a Collignoniceras woollgari Zone is hardly possi ble. The base of the Middle Turonian has been placed at the FAD of K. turoniense, at a level stratigraphi cally lower (upper Lower Turonian) than the one recently accepted. C. woollgari is rare and appears no lower than the ornatissimum Zone. The base of the Upper Turonian is placed at the FAD of Subprionocyclus neptuni. Romaniceras deverianum appears considerably lower than the former, but has 158 THOMAS KOCHLER
its main occurrence in the neptuni Zone, ranging up to overlap with Prionocyclus germari. The Barranca succession is condensed and includes hiati from the Upper Cenomanian Neocardioceras juddii Zone to the upper ganuzai! nodosoides Zone; between the Middle Turonian kallesi and ornatissimum zones; and in the lower Upper Turonian neptuni Zone. Twelve bio-events that are significant for regional and inter-regional correlations are differentiated and dated: the Mytiloides kossmati, ganuzai, reveliereanus, turoniense/her cynicus, kallesilornatissimum, Scaphites geinitzii, Subprionocyclus I, Mieraster ex gr. normanniae cortestudinarium, Subprionoeyclus II events. Most of these events are time-equivalents of events already recognised by ERNST & al. (1983) in Germany. The biostratigraphic framework permits a dating and corre lation of the major tectono-sedimentary and eustato-events, namely the Cenomanian-Turonian Boundary Event (CTBE), the Middle Turonian Event (MTE) and the Lower Upper Turonian Event (LUTE). The calcareous Coniacian - Santonian succession of the eastern Barranca (Izurdiaga, Ecay and Zuazu sec tions), is divided into Lower Izurdiaga, Zuazu and Upper Izurdiaga formations, and into numerous compo nent members. The succession is rich in echinoids, and is biostratigraphically important because of the co occurrence of inoceramids and ammonites. The Coniacian ammonite assemblages show affinities to those of the French type region and to the largely endemic ones of the Spanish standard sections in Burgos. The data obtained permit a confident correlation of the biostratigraphic frameworks of these two areas for the first time. In contrast to the widespread basal Coniacian hiatus, the Barranca succession at this level is local ly relatively complete. The lower Coniacian Cremnoceramus rotundatus, Forresteria petrocoriensis and Peronieeras subtricarinatum zones, the Middle Coniacian Gauthiericeras margae Zone and the lower Upper Coniacian Protexanites bourgeoisi Zone are recognized. In marginal sections, the bourgeoisi Zone is followed by an hiatus which comprises the late Upper Coniacian Magadiceramus subquadratus and the Lower Santonian Cladoceramus undulatoplicatus inoceramid zones recognized in the continuous section of the western Barranca. By means of ammonites, the Santonian at Olazagutia is divided into an unnamed interval devoid of ammonites; the middle Coniacian Texanites quinquenodosus and the Upper Santonian louaniceras hispanicum/Scalarites cingulatu111 Zone. This scheme has affinities with the zonation applied by KENNEDY & al. (1995) in the Corbieres, France. In addition to a sequence ofregionally important events and marker-beds, some events, namely the Didymotis II, MiCl-aster ex gr. cortestudinarium and Cladoceramus undulatoplicatus events, are of inter-basinal importance.
Contents
Introduction ...... 160 Lithostratigraphy ...... 172 Geographical and tectonic setting. . . . 161 Satrustegui II and III sections ...... 174 Palaeogeographical situation. . . 161 Lithologyandfauna .... · . 174 Previous research. . . . . 163 Integrated biostratigraphy ...... 174 Cenomanian - Turonian...... 163 Events: their lateral changes and correlation within the Barranca · . 176 SELECTED SECTIONS OF THE EASTERN Oceanic Anoxic Event ...... 178 BARRANCA ...... 163 Kamerunoceras ganuzai Event ...... 179 Arardi Section (Upper Cenomanian Spathites reveliereanus Event ...... 179 to Upper Turonian) ...... 164 Kamerunoceras turoniense!My til oides Lithostratigraphy ...... 164 hercynicus Event ...... 179 Integrated bio- and event stratigraphy ... 165 MTE (Middle Turonian Event) ...... 180 Izurdiaga Section (uppermost Lower Romaniceras ornatissimum Acme ...... 180 Turonian to lowermost Coniacian) ...... 166 LUTE (Lower Upper Turonian Event) .. 180 Izurdiaga I ...... 168 Micraster ex gr. normanniae- Izurdiaga II ...... 168 cortestudinarium Event ...... 181 Lithostratigraphy ...... 168 Ammonite/Inoceramid zonation Integrated bio- and event stratigraphy .... 169 in the Barranca .. · . 181 Satrustegui I Section (Upper Cenomanian The Cenomanian/Turonian boundary to Middle Turonian) ...... 170 interval ...... 182 UPPER CRETACEOUS OF THE BARRANCA 159
Kamerunoceras ganuzailMammites Upper Turonian ...... 200 nodosoides Zone ...... 183 Kamerunoceras turoniense Zone ...... 183 EVENTS; REGIONAL AND INTER-REGIONAL Romaniceras kallesi Zone ...... 183 CORRELATION ...... 202 Romaniceras ornatissimum Zone ...... 183 Mytiloides kossmati Event ...... 202 Romaniceras deverianum Zone ...... 184 Kamerunoceras ganuzai Event ...... 202 Subprionocyclus neptuni Zone ...... 184 Spathites reveliereanus Event ...... 202 Cremnoceramlls waltersdorfensis Zone . .. 184 Middle Turonian Event (MTE) ...... 202 Kamerunoceras turonienselMytiloides STANDARD SECTIONS hercynicus Event ...... 203 IN THE ESTELLA AREA ...... 184 Lower Upper Turonian Event (LUTE) ..... 204 Ganuza Section (upper Cenomanian Scaphites geinitzii Bed ...... 205 to Middle Turonian, kallesi Zone) ...... 185 Subprionocyclus I Event ...... 205 Ganllza IV (GZ) ...... 185 Ganuza I (GA) ...... 187 Ganuza II (Gl) ...... 187 Coniacian - Santonian ...... 205 Lithostratigraphy ...... 187 Ollogoyen Section (Middle Turonian LITHOSTRATIGRAPHY OF THE CONIACIAN to Upper Turonian, waltersd01fensislger- AND SANTONIAN OF THE EASTERN mari Zone) ...... 188 BARRANCA ...... 206 Lithostratigraphy ...... 188 Izurdiaga Group (Upper Turonian Ammonite zonation in the Estella area ..... 191 - ?Upper Santonian) ...... 206 Metoicoceras geslinianum Zone ...... 191 Lower Izurdiaga Formation ...... 207 Vascoceras gamai Zone or Neocardio- Zuazu Formation ...... 208 ceras juddii Zone ...... 191 Upper Izurdiaga Formation ...... 209 Watinoceras coloradoense Zone ...... 192 unnamed interval with rare ammonites ... 192 SELECTED SECTIONS OF Kamerunoceras ganuzailMammites THE EASTERN BARRANCA ...... 209 nodosoides Zone ...... 192 Zuazu Band C sections (uppermost Lower Kamerunoceras turoniense Zone ...... 193 Coniacian to Middle Santonian) ...... 209 Romaniceras kallesi Zone ...... 193 Location ...... 209 Romaniceras ornatissimum Zone ...... 193 General remarks ...... 209 Romaniceras deverianum Zone ...... 193 Lithostratigraphy ...... 209 Subprionocyclus neptuni Zone ...... 194 Fauna and biostratigraphy ...... 213 Cremnoceramus waltersdorfensislPriono- Event stratigraphy ...... 214 cyclus germari Assemblage Zone ...... 194 Zuazu A (Middle Coniacian, margae Zone) .215 Event succession in the Estella area .... 195 Location and remarks ...... 215 Mytiloides I Event (= Mytiloides Lithology ...... 215 kossmati Event) ...... 195 Fauna ...... 215 Kamerunoceras ganuzai Event ...... 198 Event stratigraphy ...... 216 Spathites reveliereanus Event ...... 198 Ecay E (Lower Coniacian, subtricarinatum Kamerunoceras turonienselMytiloides Zone) ...... 216 hercynicus Event ...... 198 Location ...... 216 Romaniceras kaliesilR. ornatissimum General remarks ...... 216 Event ...... 198 Lithostratigraphy ...... 216 Scaphites geinitzii Bed ...... 198 Fauna and biostratigraphy ...... 218 Subprionocyclus I Event ...... 199 Event stratigraphy ...... 218 Subprionocyclus II Event ...... 199 INTEGRATED BIOSTRATIGRAPHY ...... 218 SUMMARY AND DISCUSSION Definition of the stage and substage OF THE BIOSTRATIGRAPHICAL RESULTS .. 199 boundaries ...... 218 Lower Turonian ...... 199 Turonian/Coniacian boundary ...... 218 Middle Turonian ...... 200 Lower/Middle Coniacian boundary ...... 218 160 THOMAS KUCHLER
Middle/Upper Coniacian boundary ...... 219 Zonation of Coniacian I}pe regions, France 224 Coniacian/Santonian boundary ...... 219 Intra Spanish comparison (Barranca and Lower/Middle Santonian boundary ... 219 Burgos region) ...... 224 Middle/Upper Santonian boundary ...... 219 Ammonite/Inoceramid zonation EVENTS; REGIONAL AND INTER- of the Barranca ...... 220 REGIONAL CORRELA nON ...... 226 Cremnoceramus rotundatus Didymotis II Event ...... 226 Interval-Zone ...... 220 Micraster ex gr. cortestudinarium Acme . . 226 Forresteria petrocoriensis Zone ...... 220 Cremnoceramus deformis/Anagau- Peroniceras subtricarinatum Zone ...... 222 dryceras sp. Event ...... 227 Gauthiericeras margae Zone ...... 222 Echinocorys gravesi/Cardiotaxis integer Bed 227 Protexanites bourgeoisi Zone ...... 223 Intra-Lower Coniacian Event (ILCE) ..... 227 l'exanites quinquenodoslls Zone ...... 223 Cladoceramlls undulatoplicatus Events .... 229 louaniceras hispanicum/Scalarites Upper Lower Santonian Event (ULSE) ...... 229 cingulatum Zone .. 223 Offaster nuciformis Events ...... 229 Discussion and correlations of the Coniacian subdivision .' ..... 224 REFERENCES ...... 230
Dedicated to my white M. Repdraz-Berastegui Campanian succession of the Vistula section, Central Poland, where a refined ammonite zona tion was established by BLASZKIEWICZ (1980). Introduction Most of the localities mentioned by him have dis appeared and there is therefore little opportunity During the Late Cretaceous, the territory of to undertake new studies of this succession. northern Spain was situated palaeobiogeographi The main objective of this paper is to establish cally between the northern Boreal and the a detailed chronostratigraphical zonation of the Tethyan Mediterranean provinces. It was a Upper Cretaceous of the Navarra area, northern region of periodical faunal overlap and exchange Spain. The existence of a fossiliferous TJpper of varying intensity (compare WIEDMANN 1962, Cretaceous succession in the main part of the 1979b; WIEDMANN & KAUFFMAN 1978). This is Barranca, and the lack of stratigraphical investi why the Cretaceous successions of northern gation in that area, were the main reasons for Spain are particularly suitable for the study of the undertaking multi stratigraphical , i.e litho-, bio-, European standard stratigraphical divisions. and event stratigraphical studies. The Barranca Northern Spain was already mentioned by succession allows the establishment of a practi WIEDMANN as one of the key areas for the under cal, ammonite and/or inoceramid standard zonal standing of the mid-Cretaceous. In contrast to scheme of inter- regional significance. other areas in Europe, the upper Upper Supplementary comparative studies were Cretaceous sections of northern Spain are charac undertaken in the Estella area, in the Ganuza and terized by relatively thick and complete succes Ollogoyen standard sections for the Turonian of sions, which, at the same time, contain biostrati northern Spain; and in eastern Navarra in the area graphically important groups such as ammonites, of the Oroz-Betelu Massif. In contrast to the inoceramids and echinoids. This makes northern Barranca, the Oroz-Betelu Massif sections are Spain particularly attractive for a biostratigraph better exposed and provide more continuous suc ical investigation of the Campanian stage, cessions of the topmost Campanian and the since the classic areas, in SW France (northern Campanian/Maastrichtian boundary interval. Aquitaine) and in northern Germany (West The aim of the event stratigraphical studies was phalia) are characterized by predominantly very to recognize the succession of events in northern shallow-marine, abruptly changing facies and, Spain and to test the methodology, developed today, by an absence of available sections, giving originally by ERNST & aI. (1983) in northern very limited opportunities to study the continu Germany. Also of importance was investigation ous zonal succession. This is also the case in the of the correlation potential of particular events UPPER CRETACEOUS OFTHE BARRANCA 161 between the Barranca and central Europe. The of faulting and overthrusting, and the synclinori paper provides data on geochronological bound um is additionally traversed by N - S faults. aries, fossil distribution and eustato- and tecto The core area of the eastern Barranca was events in northern Spain. The interrelationships affected by the Estella-Dax Diapir Zone (sensu between bio-, eustato- and tectoevents were also LOTZE 1955), a SW-NE trending lineament with, investigated. in close proximity to the studied area, the associ The second part of this paper (the Campanian - ated diapirs of Anoz, 0110 and Echalecu. Maastrichtian of the Barranca), inlcuding also summary According to KIND (1967) the diapirs of Anoz chapters for the whole paper, appear in part 3 of Acta and 0110, situated today ca. 1.5 to 2.5 km south Geologica Polonica for 1998. of the study area, comprised a single structure with a common chimney. The uplift of this "dou ble diapir", which first re~ched the surface during Geographical and tectonic setting the Late Cretaceous and entered the diapir stage in the Eocene, decisively influenced the sedimen The studies were concentrated on Upper tary development in the vicinity of Irurzun dur Cretaceous occurrences west and east of the town ing the latest Santonian and Early Campanian of Irurzun, in the eastern Barranca (Text-fig. 1). (see RADIG 1973, and later in this paper). The Barranca, known as La Barranca or, in Basque, Sakana, is a geographical unit compris ing a narrow, E - W orientated valley along the Palaeogeographical situation Burunda-Araquil river, in the western part of the Province of Navarra. To the north, the Barranca During the Late Cretaceous, the Barranca valley is bordered by the Lower Cretaceous formed an independent tectonic-sedimentary and deposits of the Sierra de Aralar. Its southern bor faunistic unit of the northern outer shelf region of der is formed by the Tertiary high plateaus of the Iberian microcontinent, known variously as Sierra Andia and Sierra Satrustegui in the east, the Navarro-Cantabrian Region (CIRY 1940), and Sierra de Urbasa in the west (see Text-fig. 1). Navarro-Cantabrian Basin (FEUILLEE 1967) or The Barranca valley begins near the town of "plateform distale" (AMIOT & at. 1983, FLOQUET Irurzun and stretches for some 34 km to the west, 1983). The outer shelf area represented an ESE as far as Olazagutia, where it passes into the WNW zone comprising several intra-shelf basins Vitoria plain (Text-fig. 1). with different sedimentary facies and subsidence Within the Barranca, in addition to 2000 m of histories related to tilted block tectonics (see Albian clays, predominantly marine, Upper Text-fig. 2) within a strike-slip- and/or oblique Cretaceous sediments crop out, structurally form slip-fault system (WIEDMANN & at. 1983, ing a large synclinorium. In the northern part of ENGESER 1985, ENGESER & al. 1984). This zone the eastern Barranca the E-W Aralar Fault sepa stretched from western Navarra, through the rates the synclinorium from the Aralar anticline, province of Alava, to the northern part of the which is formed of Aptian - Albian reef lime province of Burgos. Fault-zones, interpreted as stones with a core of Triassic and Jurassic lime the Bilbao transcurrent and Losa transcurrent stones and dolomites. Parallel to the Aralar Fault, faults (Text-fig. 2), separate the unit of intra in the south, runs the Satrustegui Fault, which sep shelf basins from the deep marine basins to the arates parts of the Upper Cretaceous Synclinorium north and the proximal shelf of the "plateform from the synclinorium of the Tertiary high plateau, nordcastillane" (sensu ALONSO & FLOQUET 1982, the core of which is composed of Eocene lime AMIOT & al. 1982) to the south. Within the zone stones. In structural terms, the Barranca can be of the Navarro-Cantabrian basins, the Barranca interpreted as a graben (RAMIREZ 1987). represented the most northeasterly located unit. It In the eastern Barranca, the Upper Cretaceous is is limited by the SW-NE trending lineament, tightly folded, with mostly WNW-ESE trending known variously as the Estella-Dax Diapir Zone (Pyrenean direction) and south-vergent synclines (sensu LOTZE 1955), Estella Fault (sensu and anticlines which generally plunge to the ESE SCHWENTKE 1990) or part of the Basco-Landaise at low angles. Numerous E-W trending faults Transversals (sensu SCHOEFFLER 1982) (see divide the fold structures into separate blocks. The Text-fig. 2). This lineament separates the margins of the synclinorium are marked by zones Barranca from the higher lying region of the 162 THOMAS KUCHLER
A
Oroz-Betelu Massif
limestones SS : San Sebastian EJ submarine steep-sided furrow with volcanism calcarous flysch B : Bilbao r-:-l alternation of ~ limestones and marls P : Pamplona emergence • hiatus I Imarls • r------B sw NE I , ~ Nor/h Cas/iI/ian Pla/~forl1l Nararro-Calllabrian Basins I --',
Estella Ba5111 Barranca Jilama Basill
Fig. 2. A - Palaeogeographical position of the Barranca within the zone of Navarro-Cantabrian intra-shelf basins during the Turonian (modified after ALONSO & FLOQUET 1982 and AMIOT & 01. 1982); B - Structural-facies cross section through Navarro-Cantabrian intra-shelf basins during the Turonian UPPER CRETACEOUS OF THE BARRANCA 163 so-called Pamplona Basin. Based on thickness papers by WIEDMANN (1962, 1965, 1979a, b) on differences between it and the Estella Basin in the stratigraphy and palaeontology of northern the south, and the adjoining deep-marine Biscaya Spain in general. With inoceramids the case is (or Ulzama) Basin to the north, the Barranca is similar (WIEDMANN & KAUFFMAN 1978; LOPEZ interpreted as a zone of tectonic uplift (Text-fig. 1990, 1996). The Campanian echinoids of the 2B). In the Estella area, the Upper CretaceOus Barranca were first studied by RADIG (1973), who succession (the Upper Campanian is usually investigated their vertical and geographical distri lacking) is approximately 1500 to 2500 m thick bution and provided useful sections. His sections (compare WIEDMANN & al. 1983, SCHWENTKE & served as a basis for the present study, and for the WIEDMANN 1985), while in the Biscaya (or establishment of an integrated ammonite-echinoid Ulzama Basins) it reaches 3000 to 3500 m (com biozonation for the eastern part of the Barranca pare EWERT 1964, VOLTZ 1964, WIEDMANN and for the Urdiroz/Imiscoz area (see KUCHLER & 1979a, SCHWENTKE 1990). Within the Barranca, KUTZ 1989). Detailed stratigraphical studies and the thickness of the Cenomanian through mapping in the context of Diploma projects of the Maastrichtian succession is estimated at ca. 800 Free University, Berlin, were carried out by KUHN to 1050 m in the eastern part (DEGENHARDT 1983, (1982), DEGENHARDT (1983) and KUCHLER (1983), KUCHLER 1983), and a maximum 1350 m in the describing the eastern part of the Barranca, and by west (KANNENBERG 1985, ZANDER 1988). ZANDER (1988) and KANNENBERG (1985) for the WIEDMANN (see LAMOLDA & al. 1981, western part. The eastern part of the Barranca was SCHWENTKE & WIEDMANN 1985) called the also treated by COSULLUELA SOLANILLA (1986). Barranca the Barranca Horst, and ENGESER Details of the biostratigraphy of the Turonian/Co (1985) regarded it as the submerged part of the niacian boundary and of the Lower Coniacian Aizgorri -Basement-High. from the environs of Irurzun, including detailed It can be generally demonstrated that the sections with ammonite and inoceramid distribu Barranca depth developed westwards, while at tion, were provided by KUCHLER & ERNST (1989). the same time, from the Late Cenomanian to the LOPEZ & al. (1992) presented the first list of Upper late Early Campanian, exhibiting a mosaic, large Campanian inoceramids from the eastern Barranca ly controlled by tilted block tectonics, of internal within the biostratigraphical framework of swells and sub-basins that are clearly document KUCHLER & KuTZ (1989) based on ammonites and ed by strong facies differentiation, thickness echinoids. variations and hiati of varying duration from east to west. Consequently, the Barranca can be sub divided into a West, Middle and East Barranca Cenomanian - Turonian (see FEUILLEE 1967). SELECTED SECTIONS OF THE EASTERN BARRANCA Previous research The lithological character and faunal composi In spite of a large number of stratigraphically tion of the Cenomanian - Turonian succession of important publications in the last 35 years on the the eastern Barranca discussed in this paper are Upper Cretaceous of northern Spain, only a few of based on the Arardi, Izurdiaga and Satrustegui them were devoted to the Barranca region. Among sections, including 6 outcrops over a distance not them the micro biostratigraphical and microfacies exceeding 7 km (see Text-fig. 1). Only the first studies on the Cenomanian and the entire Upper two sections are stratigraphically relatively com Cretaceous, mainly of the western Barranca, of plete: uniquely for the Barranca a macrofossil FEUILLEE (1966, 1967) and RAMIREZ DEL POZO -rich succession with ammonites, inoceramids (1971), respectively, are of great importance. and irregular echinoids that extends from· the Preliminary data on the stratigraphy and sedimen Cenomanian to thc basal Coniacian. The sections tology of the Olazagutia Quarry were presented by more to the west, including those of Satrustegui, RADIG (1973), LAMOLDA & al. (1981) and GRAFE partly because of faulting are more or less discon (1994). Some data on isolated, mainly unhori tinuous, and partly due to the existence of strati zoned ammonite finds from the Barranca, as well graphical hiati. In general they represent con as a faunal list for Olazagutia, were included in densed successions of the outer shelf with pre- 164 THOMAS KUCHLER
dominantly fine-grained carbonate sedimentation, Unit Bl: It is represented by a ca. S m thick unit of whereby the Turonian of the eastern Barranca alternating calcareous marls, hard calcareous marl hori reaches a maximum thickness of 56 m, compared zons and thin-bedded limestones. The limestone beds to the 220 m of the Estella area. The Arardi and increase upwards in thickness from 0.3 m at the bottom Izurdiaga sections were situated close to a local to about 1.I m at the top (thickening upward sequence). swell area, detected in the Middle Turonian by The whole unit is characterized by thin horizons with turbiditic ("calcisphere" packstones and echino inoceramids at the base of and within the limestone derm debris packstones) sequences within the beds. background pelagic sedimentation ("calci sphere" -foraminiferal wackestones). In the Late Unit B2: It ranges from the reveliereanus Event up to Turonian the sedimentary basin became shallow the hardground Ar-74, and represents an S to 9 m thick er, shifting its position from deeper to shallower succession again composed of an alternation of ini subtidal towards the high or swell region. The tially metre thick calcareous marls (decreasing in shallow subtidal is indicated by shallow marine thickness upwards) and thin-bedded (0.1-0.2 m) lime hardgrounds (echinoderm debris wacke/pack stones. stones) of neptuni Zone age and terrigenously influenced, silty and strongly glauconitic carbon Unit C: At the Arardi it is a ca. 2 to 2.4 m thick (tec ates in the Turonian/Coniacian boundary interval. tonically reduced) succession of alternating, nodular, The Satrustegui section was located in the transi 0.15 to 0.3 m thick limestones and 0.15 m thick marls. tional area to the basinal facies, while clearly The unit is characterized by four hardground horizons basinal conditions are documented by the sections (Thalassinoides hardgrounds) and two (between beds of the western Barranca in the area between Hg-74 and Hg-7Sa), 0.2 to 0.3 m thick calcarenitic Iturmendi and Alsasua (see ZANDER 1988). beds. The three lower hardgrounds are penetrated by large-sized Thalassinoides burrow systems with glau conite coatings. Between the hardgrounds and the over Arardi Section lying marls there is an erosional contact. The burrows (Upper Cenomanian to Upper Turonian) are infilled with calcarenitic marls (packstones with echinoid debris) and intraclasts of the hardground. The Arardi section (Text-fig. 3) is situated ca. Intraclasts, partly bored, and with a glauconitic skin, 3 km SE of Irurzun, south of the motorway A-IS also occur within the marls above the hardgrounds Hg- at the Arardi Mount. It is represented by a natur 74 and Hg-78a. The hardground suite is capped by a al outcrop (Topographical map Gulina, sheet 0.6 m thick nodular limestone bed (Ar-SO) penetrated 115-9,1:10 000; R=597.450, H=750.400), in par by Thalassinoides burrows, representing a "composite allel to a brook running about N-S east of the hardground" in the classification of KENNEDY & Arardi Mount. The figured succession (albeit GARRISON (1975). largely overgrown) is about 50 m thick and com prises the interval from the Metoicoceras ges Unit D: A limy marlstone unit with single 0.1 to 0.2 m linianum Zone of the Upper Cenomanian up to thick limestone intercalations. Compared to the the Subprionocyclus neptuni Zone of the Upper Izurdiaga section, the unit is tectonically reduced to Turonian. about 4 m.
Lithostratigraphy Unit El (4.6 m): A 1.4 m thick succession of alternat ing 0.3 to 0.4 m thick limestones and calcareous marls The Turonian succession of the Arardi section occurs at the bottom of this unit. The higher part of the can be divided into seven informal lithological unit comprises a much more closely spaced alternation units, briefly characterized below (in ascending of decimetric calcareous marls and 0.05 - 0.1 m, nodu order). lar, finely arenitic limestones or nodular limestones (glauconitic echinoid debris-packstones). The unit rep Unit A: Ca. 12 m thick unit, overlying Upper resents reworked sediments redeposited into the area of Cenomanian limestones, of thin-bedded calcareous deeper subtidal. The allochtonous material comes from marls (~78% CaC03), with thin (0.1-0.3 m) limestone a nearby swell area with echinoid facies. The unit ter intercalations passing gradually upwards into marls of minates in a planar hardground (Ar-S9) with a well the overlying Unit B 1. developed Thalassinoides burrow system. ,. n c:: UPPERi LOWER TURONIAN MIDDLE TURONIAN IUPPER TURONIAN\ "0 cr.. I i ,. "0 ~ '!!. i ! ;,-" ,,~~ ..-' i Ii' o ~n -(-j- ~iS' "" ~ ~ § ~ft---> +-(p!,~ ... (I) I ::j e 0:, 25 1"0 :::. j I "';; ('0'" ~ ~, I I • ;;;, , 0 ~.~, ., .< ,~t "S! 'I ~ I~rnrn~i~~ "' 0 g. ~ I a ~ ~:., E' t;i ~ ;;l) i g- ~~ :; 5 5 n .! I ~ ~ '" ~ ~ ~ ~ ~ +-+ § lj "~ -'! o g" ! +---r '" il ~ ( ";i i1" n " >- i~ cc cc >- N t;;; ;:; 9- I In I I '" I I "~. g ~ S: ~ , I II I IJQ ~ ~ r f " :=- • ~~~;;~ ~ ~,=~';.::' •.f·t· l: ;~e te~e:e ~ ';.. ;;; ~l ;; ez~~~s!;l~ j~ ~ .,l~; :;:.~le ~
~ ~ g s· [~ li < ••. i ~ p;' ~ c .g. z ~ ~ § ~ ~ ~ ~ I l !j~ ~ ~ ~. 1 H[ t § 3 a t'; g J- ~ if• il. lU P Ul !:J ~ (3 " j, ~ ~ S i ~~ ~ 8, ~" ;: ~~ ~ ~ ls2~8:g:g:e ~B:S:~ $ c5;::;j~~O:;;~: ~ fj ~~~ ~ gg~~ if ." ...... "_ . .. I... ,SClponoceras s~. ,...... ')11' '\ j I . ~ tJ I . j---it--~I: ::r:1:: ...... ':.: .. j" : . ..II·· ~ciponoceras sp. cf. bohemicum a. I 1 jlt ' I' Kamenmoceras ganuzQI § ;;; 1 I +...... II·f ..... ·.. ·· 1··· .. · .+. .- I r ~achydesmocems den~·sonianllm "0o g_ .. r·· "'j'" . .. I . Kamerunoceras turonzen~e ~ ~. 1...... I·'.... ,... ,..... i' j I Spa!hites (Jeanrog.) r::Ve/iereanu", I ,.. j...... r···· .. ···· ...... +,...... l'vlammites cf. nodosoides > 3 §.' n' 1 ~ ~ t·····,· '·r.. '· .. ·.. ··· .. .l..lr· ... , ...... ····{··T ".'... N. (Eubastrychoceras) afC matsumo!oi 3 n IJQ f :3 ;:; 0' '0 ~. :: ..- ;:;: I ,'jt::...... :lc:rL::·::~:~~l:·: ~fi~f;;~1?~1;ir;~i ;0- I IJQ M :3 '? ?Collignoniceras sp c ~ ...... ,...... ,...... ".".... j .. ·1·· 'R or I I I II i • .j.. Tongoboryceras sp. 9' • • • • I . Tongoboryceras rhodanicum ~ i5.. I ; ... !.~.· .. :" .... I.. 'I ..... Neoc~oceras sp. cf. multinodosus ~ •... i.~ ...... Bacuhtes undulatus < 'i ffi ' Inoceramus pictus bohemicus ~ ...... ' .. y... ~ ...... ,.. ,.. ,·,,·,,· ... ··1 H .. · ...... ,."",.,, ...... ·· ..1 ,+. ...~. "'1' ...... I· , ~'!...... 11 111 ·· ···· .. . .." ...... +....lt···,J T Myti/oides sp. . :; ~. j 0 "0 ,.,...... ,...... j l"1 .... j.. . '1' . j: "':.': '::::::::::::::::I:::JI:L::::::::: " :=- n:: .. f' ~. :l:: ~~;~:~:~ ;;"/~;de/,ablQtus ., '< •...... j ...... j ...... '1 • •••• ...... • ...... '.".' .j ...... ~ ..... M. aff. hercynieus " ..3 ~ c.~ 'I t .. . "" ..· .. ···r"l":::I:r:::::::::::::i: ~o:.:~:::,:c~o"'!e/Iatus ~ [ 1 III l : ·r"· Inococeramus webster! I 1 L _ J j __ l ..... Cremnocemmus waltersdoifensis ~ ~ ~ II I" .• : •"'1"[""['['" ConuIus subronmdus .1'11 ...... ···· .. ·· .. 1·· .. ··1· .. ······ .. ·.. ,.. ":"· Micras!er (Eomicroster) sp. .. ~ 1 ~ r I I ~ ___ I Ai ~X. gr. normanmae-correstudznarlum 8, I 1 tf:=±1 ~I -J ~ ~ ~ A §l (') ~~ ~ 0 :;~:::: .., §" §.. §" ~ r n c Bay of Biscay o • 1 Echa~--~---L---L--~--~ Aizgorr' _------_ I 010z09 SATRlSTE G UI ··· ···t · { 1\ S8l1t lll ( ' . Sail" II~ Satrustegul I 500 1000 m un/eneta : sections Urd Urdiain Vii Villanueva de Araquil Ec Ecay E Erroz Iz Izurdiaga La Larumbe Sa Sarasate 3 Iturmendi I, II 1 Alsasua (road-cut) It Iturmendi Satr Satrustegui Ech Echeverri 01 0110 Aiz Aizcorbe 2 Olazagutia quarry 4 Iturmendi (cemetary) Echa Echalecu Er Erice de Iza Ba Bacaicoa Zu Zua zu Ur Urrizola An Anoz Gu Gulina Geological sketch-map of northern Spain with location of the Barranca and other reference areas mentioned in the text ( I A) , and the geographical location of the in vestigated sec tions in the western and eastern Barranca (IB); IC. General view of the eastern Barranca (Sakana) and the eastern part of Sierra de Satrustegui, as viewed from WNW; Upper Cretaceous exposures are located mostl y at the northern slope of Sierra de Satrustegui and in the east, at the slopes of the Arardi and Astieso mounts near Irurzun . UPPER CRETACEOUS OF THE BARRANCA 165 Unit E2: In the Arardi section the 5 m thick unit starts soides Zone is first documented by an ammonite with two horizons of reworking: the Arardi and inoceramid fauna occurring 5.7 m higher, Conglomerate and an intraclast horizon. Above this, following an unexposed interval. Kameruno there is a marked Iithofacial and microfacial change to ceras ganuzai (WIEDMANN) (Pl. 5, Figs 9-10), the so-called Lower lzurdiaga Limestones. The Arardi characteristic of the zone in northern Spain, Conglomerate is composed of a layer of flat centimetre appears together with Sciponoceras cf. to decimetre limestone pebbles with phosphatic and bohemicum FRITSCH (Pl. 5, Figs 5-6) in a ca. glauconitic coatings. The nodules are bored all around 0.3 m double limestone (bed Ar-53), in the so and are partly encrusted by oyster-like bivalves and ser called ganuzai Event. Mytiloides ex gr. labiatus pulids. The overlying, intraclast horizon, ca. 0.2 m (VON SCHLOTHEIM) and Mytiloides mytiloides thick, is characterized by irregularly shaped, in part (MANTELL) are also associated with this form. fist-sized matrix-supported intraclasts, phosphatized The succeeding 0.6 m thick interval contains sev steinkerns of ammonite as well as corroded echinoid eral horizons with Sciponoceras and Mytiloides. tests. This horizon is followed by nodular, 0.2 to 0.3 m The Mytiloides assemblage comprises thick on average, silty and glauconitic limestones and Mytiloides labiatus, M. aff. duplicostatus marls (echinoid debris packstones). The unit is marked (ANDERSON), M. aff. l11ytiloides, and M. aff. her by the first appearance of Micraster ex gr. normanniae cynicus (PETRASCHECK). The assemblage exhibits - cortestudinarium. a high species diversity, as well as containing morphotypes with great morphological variabili Integrated bio- and event stratigraphy ty, both features that are typical of upper Lower Turonian Mytiloides assemblage elsewhere Six ammonite zones can be distinguished with (SEIBERTZ, pers. cOl11m.). M. aff. hercynicus is in the Turonian of the studied section (see Text abundant within the assemblage. It was interpret fig. 3). The inoceramid associations occurring ed by SEIBERTZ as a hercynicus form with labia within the Lower to middle Middle Turonian are tus characters, but was referred by Ie. WOOD attributed to the corresponding ammonite zones (pers. comm.) to Mytiloides hercynicus sensu but an inoceramid-based zonation was not estab SORNAY. lished here. By contrast, ammonites are rare in The topmost Lower Turonian of the Arardi the topmost Turonian of the Barranca, so that section is marked by an upper Mytiloides acme only on the basis of a similarly sparse inoceramid zone, 3.5-4.0 m thick. It is characterized by sev fauna can this part of the succession be assigned eral horizons with mainly late forms of to the Cremnoceramus waltersdorfensis Zone. Mytiloides labiatus, associated in beds Ar-60 Conforming to the regional situation, the and Ar-62 with Pachydesmoceras denisonia Cenomanian/Turonian boundary interval, the num (STOLICZKA) (Pl. 6, Fig. 1). This acme-zone Middle Turonian (between the Romaniceras in the Barranca extends up into the kallesi Zone and Romaniceras ornatissimum Kal11erunoceras turoniense Zone (lower Middle Zone), as well as the lowermost Upper Turonian Turonian of this paper). (Subprionocyclus neptuni Zone) of the Arardi section are characterized by stratigraphical gaps. Middle Turonian: The lower boundary of the Middle Turonian, following the traditional defin Lower Turonian: In the Arardi section, the ition in France, and also for practical reasons, is lower boundary of the Turonian is located at placed here at the FAD of the ammonite species horizon Ar-52, the level of the first occurrence of Kamerunoceras turoniense (D'ORBIGNY). This is poorly preserved inoceramids transitional contrary to the proposal of the 2nd International between Inoceramus pictus and Mytiloides Symposium on Cretaceous Stage Boundaries in mytiloides that belong to the Cenomanian - Brussels, Brussels 95 (BENGTSON 1996), which Turonian transition (TROGER, pers. comm.). The placed this boundary at the FAD of Collignoni Turonian age of this horizon is also indicated by ceras woollgari (MANTELL). The latter species a planktonic foraminiferal fauna comprising does not, however, occur in off-shore areas. The Praeglobotruncana and double-keeled forms of level adopted here is stratigraphically lower than the genus Marginotruncana (NEUWEILER, pers. the one accepted in NW Europe. comm.). Unequivocal upper Lower Turonian In Arardi section the lower boundary of the Manunites nodosoides Zone or ganuzailnodo- Middle Turonian lies in bed Ar-64 (Text-fig. 3). 166 THOMAS KUCHLER It is characterized by the co-occurrence, in primarily in the upper part of the deverianum approximately equal numbers, of Mytiloides Zone. Due to rarity of the index taxon, the lower labiatus and M. mJ. labiatus/hercynicus, as well boundary of the zone in the Arardi section cannot as subordinate M. mJ. labiatus/subhercynicus. be precisely placed. In contrast, its upper bound According to SEIBERTZ (pers. cOl1un.) the hercyn ary with the neptuni Zone is well marked by two icus-like forms occurring here do not represent superimposed horizons of reworking, yielding true hercynicus forms but morphotypes that have both Middle as well as Late Turonian ammonites. been ecologically controlled. This level, referred These include mainly juvenile Tongoboryceras to here as the Spathites reveliereanus Event, sp. and Tongoboryceras rhodanicum (ROMAN & coincides with the level of first appearance of the MAZERAN). ammonite species Kamerunoceras turoniense (PI. 6, Fig. 2), a form used in France as the guide Upper Turonian: The base of the Upper form for the base of the Middle Turonian (tur Turonian is defined by the FAD of Inoceramus oniense Zone). The dominating S. reveliereanus costellatus WOODS. The ammonite marker of this (COURTILLER) (PI. 6, Fig. 6) is locally accompa boundary, Subprionocyclus neptuni (GEINITZ), is nied by Mammites cf. nodosoides (SCHLUTER) absent in the off-shore areas of the Barranca. (PI. 6, Fig. 5). Single horizons within the tur The neptuni Zone is indicated here by single oniense Zone yield Kamerunoceras ganuzai finds of the ammonite species Neocrioceras (PI. 6, Fig. 3) co-occurring with Mytiloides labi (Schlueterella) cf. multinodosum (SCHLUTER) atus and Nostoceras (Eubostrychoceras) aff. and Baculites undulatus D'ORBIGNY (PI. 8, Fig matsumotoi COBBAN. Single Mytiloides labiatus 5), as well as 1. costellatus. Micraster ex gr. nor and Mytiloides hercynicus, occurring within manniae - cortestudinarium appears 0.7 m beds Ar-70 to Ar-71 indicate the turoniense/her above the Arardi Conglomerate. cynicus Event. In contrast to the Izurdiaga sec The Cremnoceramus waltersdorfensis Zone is tion, the event here yields an impoverished characterized by extremely rare and poorly pre ammonite fauna, represented only by juveniles of served inoceramids, represented by C. walters S. reveliereanus. The top of the turoniense Zone dorfensis (ANDERT) and Inoceramus websteri lies in the lower part of the Arardi Hardground sensu WOODS, about 3.8-4.5 m above the rework suite (Unit C). The fossil association occur ing horizon. ring here is composed of Kamerunoceras ganuzai, K. turoniense, Neoptychites cephalotus (COURTILLER), Puzosia cf. planulata (BAYLE) Izurdiaga Section (uppermost Lower and Conulus subrotundus (MANTELL). Turonian to lowermost Coniacian) The succeeding, kallesi Zone is recognized by the finds of Romaniceras aff. kallesi ZAZVORKA South of Irurzun, between the villages of (PI. 8, Fig. 2) and R. cf. kallesi. The zone is Izurdiaga and Erroz, the Rio Araquil cuts through restricted to a 0.2 m limestone bed (hardground the Upper Cretaceous succession (see Text-fig. 78a) and a thin (0.05 m) marly bed. Both, the 1). This transverse section, situated east of the eroded hardground and the intraclasts within the railway, and some other nearby sections served marl, as well as the occurrence of Romaniceras CABAYO & al. (1978) for a rough description of ornatissimum (STOLICZKA) at this level in the the Upper Albian through Maastrichtian succes Izurdiaga section (in the Arardi section this form sion in the area, in the context of the geological was not found), indicate strong condensation mapping of the Gulina sheet. The biostratigraphy and/or extensive reworking of the kallesi Zone was based on the microfauna. The locality (MTE - Middle Turonian Event). As in the case Izurdiaga is known also from the palaeontologi of the kallesi Zone, the ornatissimum Zone is cal studies of WIEDMANN (1962), as well as from also strongly condensed; it lies here within the the stratigraphical studies of FEUILLEE (1967), composite hardground Ar-80 (see Text-fig. 3). RADIG (1973) and KUCHLER & ERNST (1989). The Directly above enters Tongoboryceras sp. lithological characteristics of the section were which, in the Barranca, generally represents a described by DEGENHARDT (1983) in his Diplom characteristic element of the succeeding, deveri Thesis. U nfortunatel y, he referred the Turonian anum Zone. This genus, accompanied by strata to the Coniacian. His section at the north Romaniceras deverianum (D'ORBIGNY), occurs ern boundary of the village is referred to here as sp!U1m;);)oUJ pUB S::l)JUOLUUlll JO S;)ilUB.I Ill;)0l pUB :Aqdll.lill)1l1)S lUgA;) pUll -OIq '-OIIJII p;»)ll.lil;))UJ :UOI)J;)S II nillllp.mzI ;)q) JO UOISS;););)nS llBJUO.ml ;)IPPlJA,[ 0) .1;)"0'1 "j? "illd LOWER TURONIEN MIDDLE TURONIEN 0 .... ~ ~~ I::! ::i ;::;: iXl ..., til ~ rnrn~i~ o s:::i 0 ;::;: ;::;:~ ==::J 5' 3" ~" 3&. 0" 3' 3' ~ %- ~ 0 I!> I!> (I) ::l. ;::;: ("") '"c- !!l- 3 ~ '< ~ ~ c., ~~ I!> 0 Q) til o ~ ;j 0 =- 0- ~ ;j 3 ~~ til 0- I!> til ~ ffi= I!> - I!> '" c., c., :J3 0- c ol!> ;j .,.!!l- D. O-li O-;j'" 0 co 3" I:I:l I:I:l I!> ~ '" > .... N mffi li Cil c- o , , I!> :J ~ N _, 0 _0- I!> iii" 0 v: , ~ .I>- ~ ~ I I ¥ ..0- 00 00 0000 1--1 ~ 0 0 {3 (;; t: -;::; '" b:'-' b:~t-t- 8 N f;§ee~~i:t g C 'b~~"-':..ewv~~ ';: ~e ~ t;: ;t ~ e • ..c III 0 0 e III C ••c- o (\) c 3 Cil ;j ! ;j 0 § .,0- 3 "< 9 :J0 t 0 .....,; ~ - ~ ~ ~ "0 ! > V '"(\) 9 ~ ~ 0" 0 0 3 f.------t (\) '" ~~~ ! > ~~~ '" .....,; "- ~ ",,"00 ~a~ "~ ~ .-"- ._~._.- ~ .....,; &i '" <:l ;:l i8 ;;:l :;;' vl -j= :::l ~ ~ ~ ::3 el ~ 88 8~ 8,- o •••••••• ~ ...... Choffaticeras quaasi ...... "0 •••••• ...... Spathites (J.) robustus .. Spathites (J.) reveliereanus ...... Spathites (/.) malladae ...... ::1::::::r::::::::::: ...... Kamerunoceras ganuzai >e . Kamerunoceras turoniense e ... SCiponoceras bohemicum ~...... Placenticeras aff. cumminsi ~ '" Nostoceras (E.) sp. nov. " ... N. (E.) aff. matsumotoi ...... Pachydesmoceras sp ...... Cibolaites molenaari 4." Fagesia aff. catinus ...... Mytiloides gr" labiatus ..... M. mf. labiatuslhercynicus = -!")= ~ ...... Mytiloides mytiloides =-; .. M" cf. hercynicus e ....c=.. ~ ...... My tilo ide s cf. kossmati '" V" l'>'l iii iii c:- ..: tT tT ~ ~ iii" III a;:, :=..... iii' rI> c:- c:- ;;:s: (D' (I) C/) m(l) m;:' ~:= lllet < (I) Q. lllQ: (\)(1) ~~ (1)(1) a.;:, ~ L91 \f;)N\f The section (Topographical map Gulina, sheet Unit B2: As in the Arardi section this 9 m thick unit is 115-9, 1:10 000; R=595.800, H=4.750.800) is characterized by two, up to 0.4 m thick limestone beds located at the eastern boundary of the village of (IzII-78 and IzII-90) in a 2 m interval above the reve Izurdiaga (Text-fig. 1 and PI. 1). The exposed liereanus Event. They are characterized by thin layers succession starts within the Kamerunoceras tur of inoceramids or of inoceramid debris. They are over oniense Zone (several metres below the tur lain by 4 m thick marls including a 1.2 m thick calcare oniense/hercynicus Event) of the Middle ous marl bed, containing an ammonite/inoceramid Turonian and extends up into the Lower layer. Toward the top, the unit passes into a closely Coniacian (Text-fig. 5). spaced alternation of limestones and marls with 0.1 to 0.2 m thick limestone beds. Izurdiaga I1 Unit C: It comprises a 5 m thick hardground series, The section (Topographical map Gulina, sheet ranging stratigraphically from the upper turoniense 115-9, 1: 10 000; R=595.900, H=4.750.880) is sit Zone to the ornatissimum Zone (see PI. 1, Fig. 2). uated on the northern side of Arardi, above the Lithologically it is composed of alternating bioturbated village of Izurdiaga, along a forest track, which calcareous marls and 0.1 to 0.2 (max. 0.45) m thick runs more or less parallel to the strike of the nodular limestones. Turonian beds. Strongly weathered Turonian The 0.7 m thick basal part of the unit is composed of strata are exposed for a distance of ca. 30 m, two distinctly bedded, grey limestones (beds IzI-50), ranging from the ganuzailnodosoides Zone of penetrated by Thalassinoides burrow systems. The bur the upper Lower Turonian to the upper part of the rows are coated with glauconite. The top of the basal turoniense Zone of the Middle Turonian. In com bed (50 a) is developed as a hardground horizon with parison with the Arardi section, the lower part of glauconite concentrations and intraclasts in the burrow the ganuzailnodosoides Zone, including the infillings. Below the discontinuity surface the bed pass ganuzai Event, is either not exposed, or large es into a nodular horizon. Above lies a bioturbated cal parts of the succession have been displaced carenitic marl (0.1 m) containing isolated matrix-sup downwards, most probably at an E-W trending ported, glauconitized intraclasts. The Thalassinoides fault. The section ends above the turonienselher bed SOd has a green, convolute upper surface with cynicus Event (see Text-fig. 4). loose, horizontal Thalassinoides burrows. Immediately above the top of the bed there is a layer of irregu Lithostratigraphy larly rounded and slightly green coloured pebbles (0.05-0.07 m long, 0.04-0.05 m wide, and 0.02-0.03 m The succession of the Izurdiaga sections IS high). lithologically and microfacially very similar to that of the Arardi section, situated 1 km away. Unit D: A series of dark grey, weakly bioturbated 0.15 Nine informal lithological units are distinguished to 0.2 (max. 0.6) m thick marls, harder marl horizons ACTA GEOLOGICA POLONICA, VOL. 48 T, KUCHLER, Fig,S ~ incipient hardground frequency of specimen Inoceramids ~iv. Ammonites IEchinoids Events and marker beds =:=::J marty limestone • rare (1) ~ limestone bed • common (2-5) lime marl • abundant (>5) ~ thickbedded limestone a.a glauconite ~ nodular limestone Hg hardground == nodular limestone bed, ~ •.•.•.• fault Z limestone nodules eustatic and/or :$ ~ siltic glauconitic limestone tectoeustatic event Mieraster cortestudinarium U ,""'" ,," IZURDIAGA I < Forresteria Acme Z petrocoriensis - - mg; - 8 I 1- ~ Cremnoceramus ~ r-:l rotundatus Ii. - ~~===+-===....J Ii --' z :$ Cremnoceramus - 104 Z waftersdorfensis I~ 10- - 0 I~ - e,4-fl,:: 101 ~ _ fI,2SG,4 99 0,< f~ ~ -_ o,lstr ,b 98 j j j Eo-< ...... _.. , 0,' 97 Mieraster 0,2 j j _ 8,(SD,2 ,;;, ex gr.llomt.-cort Event 11 ., Hg ~ '. I r-:l - Subprionocycfus E2 - neptuni t - 93 LUTE ~ .- a j i Hg 92 ; I=:=t=i'=i;===i;~:==i=; ==i=~!;=~"":=t=: =;i=,==±c=-=~j±====t==t==,l""l~==t:ilf ~ ::::":: Bed 91 89 ~ 84 ? ~ ? - t D Romaniceras - MTE ornatissimum I-- ,- :;i t'" - "~ Hg Roma iceras - ::;,!:: Hg R=t:=t==i=:j=:::i=t:=t=:t=R=*~==i====I====~~ R. kallesV ~ ~ R omatissimum Event e3 1·····./i!!!!!!!.~L.. __ .. = ::: ';~ § 1--1-15-~~"~.'.;1~g~ turoniens elhercy nicus ==;i!!:; Kamerunoceras - :~'~::~~~4 ~!iif Event turoniense B2 - ..,," - 0"" f====9 M. mytiloides Bed II -20 - ~: - 1,7 M. mytiloides Bed I 0,' Middle Turonian to Lower Coniacian succession of the Izurdiaga I section; integrated Iitho-, bio- and event stratigraphy. and local ranges of stratigraphically important macrofossil groups ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 1 Izurdiaga I section 1 - General view of the Middle Turonian to Lower Coniacian strata of the section exposed at the eastern boundary of th e village of Tzurdiaga 2 - Middle Turonian (top of the turoniense to ornatissimum Zone) hardground succession ; beds position in the succession - see Text-fi g. 5 UPPER CRETACEOUS OF THE BARRANCA 169 and thin-bedded (0.1 to 0.2 m) marlstones, reaching a ganuzai (WIEDMANN), about 3 and 6 m, respec total thickness of 3.4 m, starts with bed IzI-65. Between tively above the appearance of S. robustus IzI -65 and Iz-67, in the Romaniceras ornatissimum unequivocally proves the ganuzailnodosoides Zone, there is a discordant contact, as in the Arardi sec Zone. The inoceramid fauna comprises Mytilo tion. In the later section the discordance is associated ides mytiloides, M. cf. hercynicus and M. ex gr. with a non-sequence. labiatus. UnitE1: This 5.5 m thick unit is composed of well-bed Middle Turonian: Only rare inoceramids, M. cf. ded, bioturbated limestones, in the lower part alternat kossmati, are known from the level of the reve ing with marls (0.1-0.25 m). Toward the top it passes liereanus Event (bed IzII-76). The first Middle gradually into nodular limestones and calcareous marls Turonian ammonites appear immediately above with Thalassinoides burrows. Many of the limestone the reveliereanus Event. They include beds pass into nodular horizons delimited by seams of Kamerul10ceras turoniense (D' ORBIGNY), and S. marls. There are several intercalations of 0.2 to 0.6 m reveliereanus (COURTILLER), as well as Scipono thick well-bedded, glauconitic limestones. The unit ceras bohemicum (FRITSCH), a particularly typical terminates in a 0.6 m thick, nodular calcareous marl element in the lzurdiaga and Satrustegui sections. horizon (bed IzI-92) with a conspicuous Thalassino The associated inoceramids are represented main ides hardground at its top. ly by late forms of M. labiatus and M. mJ. labia tus/hercynicus. The ammonite species Colligno Unit E2: The unit, 5 m thick, comprises a series of niceras woollgari was not found. In general, col glauconitic, fine-grained arenitic limestones and cal lignoniceratids are rare in the Barranca. The first careous marls ("calcisphere"/echinoid packstones) with record of Cibolaites molenaari COBBAN & HOOK the bedding obliterated by deeply penetrating Thalas (PI. 6, Fig. 7), which co-occurs with Placenti sino ides burrows and diagenetic processes. The beds ceras aff. cumminsi CRAGIN, in bed IzII -82 is coalesce to form m-thick horizons of nodular appear therefore particularly noteworthy in a northern ance. The basal 2 m of the succession is composed of Spanish context. In comparison to the Arardi sec incipient hardgrounds. As in the case of the underlying tion, bed IzII-82 lies about 4 m above the appear unit, the unit terminates in a hardground. ance level of K. turoniense. Two Mytiloides levels, characterized by repre Unit F: This 7 m thick unit is composed of very thin sentatives of the mytiloides - labiatus group bedded calcareous marls, 0.25 to 0.4 m thick, and part (according to SEIBERTZ, pers. comm., the ly well-bedded, partly nodular limestones of varying mytiloides characters predominate) occur in the thickness. Izurdiaga I section about 3.6 and 1.5 m below the turoniense/hercynicus Event. The higher Unit G: The base of this unit marks an important litho Mytiloides horizon contains M. labiatus, M. ex logical and microfacies change within the Turonian - gr. labiatus and M. kossmati, according to Lower Coniacian succession, slightly below the TRaGER'S determinations. Nostoceras (Eubo Turon ian/Coniacian boundary. The marls, calcareous strychoceras) aff. matsumotoi COBBAN was also marls and nodular limestones (with bed thickness from found in this horizon. ca. 0.1 to 0.2 m) contain a marked amount of angular The topmost, 1.5 m, part of the succession in silt-sized quartz and glauconite. the Izurdiaga II section is characterized by sever al, fossiliferous horizons (turoniense/hercynicus Integrated bio- and event stratigraphy Event), yielding a diverse ammonite fauna. Completely preserved steinkerns, mainly of K. Lower Turonian: In this section, the presence turoniense occur parallel to the bedding in. the of the Lower Turonian is testified by single finds lowest 0.8 m. S. cf. bohemicu111 (FRITSCH) tends of Spathites (1eanrogericeras) robustus to occur in concentrations on the upper surfaces (WIEDMANN) (PI. 5, Fig. 7) and Chojfaticeras of the limestone beds or within the overlying quaasi PERON (PI. 9, Fig. 8) in the basal part and marl, where it is accompanied by M. hercynicus of S. (1.) reveliereanus (COURTILLER) from bed (PETRASCHECK) . IzIl-69 of the Izurdiaga II section. The occur The upper part of this fossil rich interval con rence of Spathites (Ingridella) malladae tains an association typical of the turonien (FALLOT) (PI. 5, Fig. 8) and Kamerunoceras se/hercynicus Event at Izurdiaga, compnsmg 170 THOMAS KOCHLER K. turoniense (PI. 7, Figs. 2-5), S. bohemicum, Upper Turonian: The neptuni Zone is ca. 4.5 m juvenile S. reveliereanus, as well as rare N. thick in the Barranca. The boundary of the zone is (Eubostrychoceras) sp., Placenticeras aff. cum taken at bed Izl-92. The genus Micraster first minsi (PI. 7, Fig. 1) and Fagesia aff. catinus appears at the base of bed Izl-93. Besides (MANTELL). The Izurdiaga II section is character Micraster (Eomicraster) sp. advanced forms of ized by a local enrichment of large-sized K. tur MiCl'aster nonnanniae BUCAILLE also occur. The oniense and associated large gastropods appearance of the latter species characterizes the (Pleurotomaria) within a pebble horizon (bed upper part of the neptuni Zone (FOURA Y 1981) in IzII-94). The turoniense!hercynicus Event in the France. In Germany, early representatives of the lzurdiaga I section is characterized by a mass bucailli group, regarded by KOCHLER & ERNST occurrence of Sciponoceras sp. and M. labiatus (1989) as geographical variants of the precursor within the marly horizons. Less frequent are M. normanniae group, occur in the boundary interval hercynicus and M. duplicostatus (ANDERSON). In between the neptuni and norma lis zones of contrast, the limestone intercalations contain pre KAPLAN (1987), i.e. in the so-called MiCl'aster dominant K. turoniense, K. ganuzai, S. (J.) reve Event. The presence of the Spanish Cremno liereanus, and Spathites (1.) sp., as well as N. ceramus waltersdorfensis Zone or its time (Eubostrychoceras) sp., Fagesia aff. catinus, and -equivalent, the Cremnoceramus waltersdOl:fen Pachydesmoceras sp. K. turoniense ranges up sislPrionocyclus germari Zone which replaces the into the hardground series, the highest occurence Subprionocyclus nonnalis Zone of KOCHLER & being just below the limestone bed IzI-52. ERNST (1989), is indicated by the record of C. wal The Romaniceras kallesi and R. ornatissimum tersdorfensis as well as by the first mass-occur zones are significantly reduced in thickness, rence of Micraster ex gr. normanniae-cortestudi reaching a combined thickness of ca. 3 m, narium in bed Izl-97. This mass-occurrence of extending from the upper part of the hardground Micraster ex gr. normanniae-cortestudinarium is succession to about 1.8 m above the hardground. interpreted as corresponding to the German The kallesi Zone is possibly only 0.45 m thick Micraster Event of ERNST & al. (1983) at the base and is limited to a condensed or erosively of the Mytiloides scupini Zone. reduced hardground horizon, which yielded a few poorly preserved specimens of Romaniceras Coniacian: At Izurdiaga, the base of the sp. The overlying marl (bed IzI-55) already con Coniacian is documented by a single find of the tains R. ornatissimum. The boundary of the zone index species for the base of the Lower falls into an hiatus and lies within the marl Coniacian, Cremnoceramus rotundatus (TRaGER (kallesilornatissimum Event). In the Izurdiaga non FIEGE). It was found some cm above a level section R. ornatissimum (PI. 8, Figs 1,3) is local with poorly preserved C. waltersdOljensis ly common in the l.8 m thick interval above the (ANDERT). Of great importance is the additional hardground series, particularly in the marl below record of Didymotis sp., since the co-occurrence bed Izl-65. Equivalent strata are apparently miss of these three taxa can be used to recognize the ing in the Arardi section. Turonian - Coniacian boundary in inter-regional In the overlying Romaniceras deverianum correlation (WOOD & al. 1984, CECH 1989, Zone, the index taxon (PI. 8, Fig. 4) occurs more KOCHLER & ERNST 1989, WIESE 1997). About commonly only in the upper part of the zone, 8 m above the first appearance of C. rotundatus, where it is associated with Tongoboryceras sp. a single specimen of Forresteria (Harleites) sp. and Puzosia sp., in the interval of, and particu (see PI. 12, Fig. 1) was found, indicating the lary above, the Thalassinoides hardground Izl- Lower Coniacian in ammonite terms. This hori 92. The latter horizon is here referred to as the zon coincides with the first acme of Micraster deverianumlrhodanicum Bed and seems to cor cortestudinarium (GOLDFUSS). respond to the level of reworked Middle and Upper Turonian ammonites and inoceramids occurring above the Arardi conglomerate in the Satrustegui I Section Arardi section. This level indicates an hiatus (Upper Cenomanian to Middle Turonian) between the deverianum and neptuni zones, caused by the LUTE (Lower Upper Turonian The section (Topographical map Ecay, sheet Event). 114-12, 1: 10 000, R=590.770, H=475.030) is UPPER CRETACEOUS OF THE BARRANCA 171 1J c: .0'" ~ -'"o :0'" snU!1V:J JJ1l VISiJ3vd ...... + ~ l%wns/vw JJll (SV.JiJ:JOl{:JtU/soqngJ N ...... ~-- sn:JlutC:J.liJl(qns JJll saplo[!ltCW .... . sn:J!utC:J.JiJl(qns SiJplO/ll tCW .... · ...... 4 SiJPIO/I/tCW P SiJPIOll/tCW .... • ...... j smvlqV/ .lil X;) SiJPIO/l/tCW .... • ...... '''T'''I''-4~ saplOl!1tCw-sn/vlqvl SiJplO/l/tCW .... • ...... 4 I 111 ! c ~ .~ Co '0'" ••• S~~~~~~' I I J~ J J J J~ I I I IQ I I I I I ...... t...... c. N. u 11 ! Isalnoq l} 4:>S~I:l .. 1, 1~,11 :: , .." , t: ..... ' "... ::'"" ~ :,: ~ . 1Jc .5 ~: :::I c to a:: I e '" 1J ~ jJ -= ~: ~ l''" 1J .<: '" "" "" " ~ ..c: ~ E 0 ~ E ~ II> ., ;; E : ~ : '0 'Q. ;; II> '3 :> '0 '0 ~ : ~ cI' ~. J 0 ,§ '" ~ t·~ , .... : .l!! E .E ~ E Fig. 6. Satrustegui I section; Upper Cenomanian to Middle Turonian succession; integrated litho-, bio- and event stratigraphy and vertical distribution of inoceramids and ammonites 172 THOMAS KUCHLER represented by an outcrop along a track (see Text of light grey, in part strongly bioturbated, calcareous fig. 6), about 550 m SSW of the village of marls and fine-grained calciturbidites, is studied here Satrustegui (see PI. 2). in detail. The Upper Cenomanian to Coniacian succession The section starts with a conspicuous 0.7 m thick hori south of Satrustegui was first described by KUHN zon of dark grey calcareous marls. In the overlying 2.0 m (1982). Only the lower part of his section, which thick interval, the marls are represented by 0.2 m thick was referred by him to the Turonian, was re-inves beds. The intercalated limestones, 0.05 to 0.1 m thick, tigated here, and supplemented with two small out are characterised by wavy bottoms and sharp, locally crops, situated about 100 m apart. The Upper planar, upper boundaries. A few of the beds display a Cenomanian is developed as a ca. 18 m thick cal strongly expressed fine lamination and characters indica citurbiditic series ("flysch a boules" sensu CIRY & tive of distal calciturbidites. The number of turbiditic MENDIZABAL 1949) in the Satrustegui I section. events increases markedly in the topmost 1.2 m thick The Turonian is reduced in thickness to about 15 m part of the formation; here the turbidites are 0.05 m (see Text-fig. 6) due mostly to E-W faults. A strati thick, on average. Bed complex 67 and 68 form the first graphically and tectonically reduced Lower pronounced positive topographic feature (Text-fig. 6 and Turonian succession is exposed in the Satrustegui I PI. 2, Fig. 2). section. In contrast to the sections located in the eastern part of the Barranca (Arardi, Izurdiaga), it pictus Limestones: The Flysch it boules Formation is is more argillaceous, and resembles the character overlain by a 1.4 m thick limestone unit, starting with istics ofthe "flysch aboules", with black shale-like an 0.9 m interval composed of 0.15-0.3 m thick lime intercalations. Based on foraminifera, it is dated as stones. The following 0.4 m thick, fine-bedded horizon late Early Turonian, Helvetoglobotruncana hel of calcareous marls, topped by the 0.2 m thick top vetica Zone. limestone, is very characteristic. There is no direct Above a major fault-zone Middle Turonian biostratigraphical dating of the unit. Based on lithos strata are exposed in all three of the Satrustegui tratigraphic simulations, however, it is inferred to rep sections, ranging stratigraphically from the resent a distal equivalent of the limestones containing Kamerunoceras turoniense Zone into the Inoceramus pictus bohemicus at Arardi. It also Romaniceras ornatissimum Zone (see Text-figs appears to equate with the Iturmendi section of 6,9). These beds are characterized by limestone ZANDER (1988). and calcareous marl alternations with Mytiloides layers in the lower and nodular hardgrounds in Unit A2 (Black Marls): At Satrustegui, as well as the upper part of the succession. Lower near Iturmendi in the western Barranca (see ZANDER Coniacian (Peroniceras subtricarinatum Zone) 1988), the Cenomanian/Turonian boundary is marked marls follow discordantly above the hardground by a lithological change. In the Iturmendi section the series. The hiatus at this discordance comprises pictus Limestones of the cushmani Zone are overlain the Upper Turonian and the lower Lower by light to dark grey, thin-bedded calcareous marls, Coniacian. This hiatus, recorded also in the characterised by slightly increased Corg content. vicinity of Alsasua about 24 km to the W, Compared with the Arardi section, the A2 unit in the reflects the Intra-Lower Coniacian Event studied section is more clayey, and is distinctly (ILCE). reduced in thickness in the upper part by a fault zone, reaching 4.7 m. According to ammonite data, the Lithostratigraphy middle Lower Turonian in particular, i.e. the lower part of the ganuzailnodosoides Zone, is lacking in In the Satrustegui I section five lithological the section. units may be distinguished (see Text-fig. 6), The 0.1 to 0.2 m thick limestone beds alternate with described in ascending order below. the dm- to m-thick calcareous marls, the thickness of which generally increases upwards. KUHN (1982) Flysch a hOllIes Formation: The Plysch it boules already mentioned black shale-like horizons at this Formation (=Ciordia Formation of AMIOT 1982) rep locality. A 0.7 m thick horizon of dark grey marl (CaCo3 resents the basal part of the Satrustegui I section, and content 43%) enriched in Corg (0.91 %) and black when is here about 18 m thick. E-W running faults cause a wet, is particularly striking in this part of the section. repetition of the succession. Only its topmost 5 m This horizon (bed SatrI-75) displays the following cha thick part, represented by a closely spaced alternation racteristics: The base is composed of a 0.03 m thick ACTA GEOLOGICA POLONICA , VOL. 48 T. KOCHLER , PL. 2 Satrustegui I section 1 - General view of the exposure; 2 - Upper Cenomani an calciturbiditic succession ("fl ysch it boules" Formation) in the west of the section overlain by the p ictus-Limestones (bed complex 67 and 68); 3 - The Cenomanian - Turoni an boundary interval exposed in the track at the east side; the boundary is pl aced above bed 70; beds positi on - see Text-fig. 6; 4- Close-up view of the Lower Turonian black marl band (bed 75) UPPER CRETACEOUS OF THE BARRANCA 173 Events Ammonites Inoceramids Ech. and marker beds fault frequency of specimen 0.. '" ~ incipient hardground • rare (1) ;:: ~ oc:x::x::x:::xx: nodular limestone • common (2-5) '" .~ ..9" ., • abundant ( >5) 0.. (? limestone bed '" ], ., ... "" '" C .":;:: "=!"" ..:: ~'" (? .§ lime marl g. ~ ~ g. .~ ... '" ::s: .Q ~ c "C ;::'" .Q .~ -<:'" ~ ;::'" -<: ., .Q ., ;::'" .Q ""., '" " '" .~'" ., " £ m m R. omatissimum 0,2 1- 0 ;;i & 0,1 ,5 0,6 ~ R kallesi 0- Hg100 --'!-... _ .... _-_ .. _-?-.. - ~?:9:'i. c ~---~~-~-4--:--~-~-+~~ I'iiol -1- 1,0 ~ 0,2.Q,3 I1B 95·% . . . .:--*-+--:--:--+-+---J\l turoniensei -2- Q 94 ~ hercynicus Event Kamerunoceras 1,2 j Tli 8 -3- b 93 ::=J tu ron iense 0,1 0,5 a P! -4- 0,7 \ 92 0,4.Q,5 91 --i. -5- f""o 09:" 0,3..\\:~ reveliere8.nus "'"4"= ."Jlo,,==~~"=,=,c!f="=- 89 ~ Event -6- 0,2 - 0,2 ..!', ~"r 87 ganuzail 0,9 / (ff . -7- 0,1 ,2 85 ~0 nodosoides 0 ....l 0,4 P!! 83 Fig. 7. Lithologic-stratigraphical succession of the Satrustegui II section; events and local ranges of ammonites and inoceramids Events Ammonites Inoceramids and mad . _HgIOO 99 98 Kamerunoceras turoniense turoniensei hercynicus J Event 90 ~velieteanUS ",cd}"=. ~.!f,~~,"~~,"c=~'t=,~~ gIl 89 ...i.. vent ~ ganuzail gIl 87 ...i..~...... nodosoides TKlI96198 Fig. 8. Lithologic-stratigraphical succession of the Satrustegui III section; events and local ranges of ammonites and inoceramids 174 THOMAS KUCHLER marl bed, followed by a 0.07 m thick, light grey to white 0.6 m thick, and light-grey, thin-bedded calcareous bed of calcareous marl with crumbly texture. The true, marls. The beds in the lower, 2 to 3 m thick part of the 0.6 m thick, black marl, non-bioturbated, fissile and unit are bioturbated and yield M. labiatus (SCHLOTHEIM). with pale -coloured mica on bed surfaces, displays mm The boundary interval between the Lower and Middle thick lamination emphasised by layers rich in ferric sul Turonian is placed at the appearance of a M. labiatus phides. em-size pyrite concretions within a 0.5 m thick popUlation, that is characterized by a more extensive interval occur. SatrI-75 is delimited upwards by mas inventory of characters than the popUlations in the east sive, strongly bioturbated marly limestones. ern sections. In the 1.0 m thick interval above (SatrI-89 to SatrI-91) hercynicus-like forms occur. Both the inoce Unit Bl - B2: The black marls are succeeded by an ramids and the co-occurring ammonites, represented by alternation of inoceramid-rich, in parts strongly biotur rare Phylloceras (Hypophylloceras) sp., Gaudryceras bated, limestones and dark grey to blue grey marls as sp., N. (Eubostrychoceras) sp., and ?Lewesiceras sp., well as thin-bedded calcareous marls. The lower 2 m of are limited mainly to the uppermost 0.1 to 0.2 m of these the succession are particularly characterized by the beds. The ammonite assemblage occurring in the follow occurrence of Mytiloides. ing horizon B, beds 95 and 96, is markedly different from that found in the eastern part of the Barranca. Here, Unit C: The upper part of the section is represented by beside Sciponoceras bohemicum (FRITSCH) and intercalations of strongly bioturbated, yellowish to red Sciponoceras sp., Pachydesmoceras sp., Phylloeeras dish when weathered, nodular marly limestones and (Hypophylloeeras) sp., Gaudryeeras sp., and beds of nodular limestones. These beds show the char ?Prohauerieeras sp. also occur. Inoceramids are rare, acteristics of the onset of hardground development, and being represented only by two specimens of M. hercyn i can be assigned according to the KENNEDY & GARRISON eus and M. subhercynieus. Horizon B serves as a corre (1975) classification to the nodular chalk and incipient lation horizon in the Satrustegui area and probably rep hardground stage. resents an equivalent of the turonienselhereynicus Event of the Izurdiaga section. The ammonite assemblage in this event at Satrustegui is taxonomically markedly Satrustegui II and III sections impoverished, with the exception of Seiponoceras, in comparison with those of the eastern sections, a feature They comprise two small outcrops in two which is generally found throughout the Middle upstanding topographic ribs about 100 m SW of Turonian. the Satrustegui I section. The exposed 9 to 10 m thick succession spans the uppermost Lower and Unit C: The topmost part of the section is developed as the Middle Turonian (see Text-figs 7-8). The bioturbated, nodular weathered limestones. These lime Middle Turonian, as throughout the Barranca, is stones represent different stages of hardground devel characterized by stratigraphical condensation and opment between a nodular chalks and an incipient hard the Satrustegui sections are, moreover, tectoni ground in the KENNEDY & GARRISON (1975) classifica cally reduced. Parts of the Lower Turonian and tion. True hardgrounds, with mineralised upper sur the whole Upper Turonian are lacking. Some faces, borings and bio-encrustation, were not observed. metres above the incipient hardgrounds marls of The 0.6 m thick incipient hardground represented by the Coniacian already occur. In the Satrustegui bed Satr-98 in the Satrustegui II section shows slight III section an horizon about 24 m above the glauconitic pigmentation of the nodular parts. Fossils incipient hardgrounds contains middle Lower are rare in this incipient hardground. Coniacian strata with a Peroniceras - Scaphites fauna. Integrated biostratigraphy Lithology and fauna The Flysch a bouIes Formation of the eastern Barranca ranges stratigraphically from Middle The succession of these sections corresponds to to Upper Cenomanian. At Satrustegui, macro the succession of the Satrustegui I section as seen fossils are scarce and single finds of above the major fault. Eucalycoceras? sp. and Hemiaster sp. do not allow a more precise dating of the succession Unit B: The unit is represented by an alternation of hard, than Cenomanian in general. Moreover, neither grey limestones, or marly limestones, in beds 0.2 to macrofossils nor microfossils allow the position 'Tj cJQ' 'D S' SATRUSTEGUI II SATRUSTEGUI III SATRUSTEGUI I o~ o >-j ;reX @ Hgl~O_.",~ m ,----._____ urnu;;;Hmum ~ 99 a o \- kal/esi ::: • lorn(1tissimum d o & Hg 100 _. _~6r' :.' ----!].------Z ..." ~ 98 5' E-- kallesi 0 12, e ' ,', Hg 100 ~¢==- (1) Hg98 -1 - :$ C/l --:?----- '1'-'-' 97 ) turoniense/ ;:;. ~ L ..,;j ~ t(iij 95-96 ~ 95-% :S ~~~~.. ~ ~ ~ ~,., -2 - \ 94 hercynicus Event ~,., ~ 0' ~ C) ;::: 94 M) C ~ ~ ~, C)~ ~ "0 C b f===== ""S. 8 i:'~ -3 J 93 ~ g! g! 93 a b I §.:!: ~ en ,., <::> \ a ) .... ;::: (1) 92 ~ ~ ~ -4- --" 92 C ~ § ~ I ~ n o 91 O!! all 91 a b <:::I .t: ~II ,fI"" 90 ~ fi: ~ -5-~ 89 ..,;j ~ !"l§! reveliereanus Event _ »~ ,:.': '1-...... -6~~~~~~J :: 87 •• n ~ :;"-1 15 ~ Y ~ 7 85 ;.M";iI~~~ WMt,n~w'w ~ gil g!! C o n - = C/l ___>::_ __':"_:_____ .J~ _ ~ o gn 82•• •••• :?: ...... :.! .. : 'Tj ~ ~ ;J tTl fault ,.,'" 0z tJj 80 m ~ ~ l5 mud turbidite N C) .... 78 76 ;:::{l;::: '" ~ incipient hardground ~ ~ ~;:~r!fir_7:5 &02 ~ »n 0= nodular limestone S :: ....~ ..,,?::: limestone bed ~~ I _ _ I ~~ ~ lime marl z C=~ 67 marl ? ~z clay marl 66 ~ ! ~ ~ ~ ~ 65 ;;> TKO 96 -...) th 176 THOMAS KOCHLER of the Cenomanian/Turonian boundary to be catinus (MANTELL), a large population of inoce indenfied. ramids was collected from bed SatrI-88. According to SEIBERTZ (pers. comm.), the inoce Unit A2 belongs, however, to the Lower ramids are represented mostly by juveniles of Turonian. Based on foraminifera, bed 73 already Inoceramus cuvieri SOWERBY and much rarer M. has to be placed in the Helvetoglobotruncana cf. mytiloides (MANTELL) and M. subhercynicus. helvetica Zone. Consequently, the black marl W ALASZCZYK (pers. comm., 1995) referred these horizon (bed 75) belongs to the ganu forms to M. ex gr. labiatus - mytiloides and to M. zailnodosoides Zone of the ammonite zonal subhercynicus. A microfaunal sample from the scheme. This dating corresponds well to that of marl directly above the incipient hardground Hg- the black marl in the Iturmendi section (Text 100 was dated, according to ZANDER (pers. fig. I 0), which likewise lies in the helvetica comm.), as Marginotruncana schneegansi Zone. foraminiferal Zone. The incipient hardgrounds of the Satrustegui sections equates with the hard In the Satrustegui I section, the 9 to 10 m thick grounds in the middle part of the Arardi and interval of the succession occurring above the Izurdiaga sections. The latter were assigned to main fault belongs to the Middle Turonian on the the upper K. turoniense and R. ornatissimum basis of the inoceramid - ammonite assemblage. zones of the Middle Turonian. The fauna is composed mainly of inoceramids, At Satrustegui, upper Lower Coniacian marls concentrated within the basal 2 to 3.5 m of the follow discordantly and a short distance above interval. Ammonites are relatively rare. There is the hardground series. The contact is marked by a quantitative predominance of planktonic forms, a stratigraphical gap comprising the Upper compared to the assemblages in the Turonian and basal Lower Coniacian. The dis Arardi/Izurdiaga sections. Stratigraphically cOl'dance and hiatus are traceable westwards important forms were collected mostly by KUHN through the Alsasua section in Navarra (ZANDER (1982) from his Al and A2 horizons and proba 1988) to the Ucuma/Eguino section in Alava bly from only one interval corresponding to that (W OLZ 1985). between beds 85 and 91c. Accurate placing of KUHN'S material is, however, not possible. According to the re-examination of this material, Events: their lateral changes and correlation it mostly comprises Kal11erunoceras sp., within the Barranca Kal11erunoceras cf. turoniense and Spathites (Jeanrogericeras) sp. together with rare Pachy In a classic sense events are short-lived geolog desl110ceras sp., Lewesiceras sp., Sciponoceras ical processes, e.g. gravity mass flows, tur sp., S. bohemicum, N. (Eubostrychoceras) aff. bidites, tempestites, which happen during a peri matsumotoi, Ph. (Hypophylloceras) sp. and od of only a few hours or days, and which occur Fagesia sp. Compared with the eastern sections, repeatedly with an interval between 100 and this assemblage together with the co-occurring many thousand years (compare EINSELE 1993). inoceramids, indicates the upper turoniense These event beds seem to be controlled by the Zone. In the planktonic foraminiferal zonation it authogenic processes within the sedimentary still corresponds to the helvetica Zone (LAMOL basin. On the other hand, some of them can be DA,pers. comm.). confined to the allogenic, cyclic processes, such Bed SatrI-82 is characterized by the common as climate or sea-level changes. The thick and occurrence of M. ex gr. labiatus. The inoceramid widely distributed mud flows and mega-breccias population (from KUHN'S collection) is represent are mainly caused by sea-level fall down to ed by forms with a mixture of the morphological below the shelf edge (EINSELE 1993). Turbiditic characters of both labiatus and subhercynicus, as sequences commonly occur, in sequence strati well as morphotypes with characteristics of graphic terms, within the lowstand deposits, but mytiloides, subhercynicus, labiatus and pictus also can occur in other system tracts and likewise (SEIBERTZ, pers. comm.). M. labiatus occurs in a continuously prograding delta succession. commonly, while typical representatives of M. The position of tempestites in the shallow-water subhercynicus (SEITZ) are rare. In addition to a sequences of 3rd order or higher is, according to single specimen of the ammonite Fagesia aff. EINSELE (1993), less clear. The origin of sandy ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, Fig. 10 TURONIAN EVENT CORRELATION WITHIN IZURDIAGA m AMMONITE THE BARRANCA (N-SPAIN) ZONES M F. perrocoriensis Local FADs of index species ~ tecto eustatic event 1 . cortestudinarium 20 -- -- __ _ Inoceramus pictus bo hemicus ~ "black shale" horizon ARARDI SUbprionocyc Spathites robustus siltic glauconitic limestones @ 0 nor.a.J.is S. (Ingridella) malladae 10 . gr. normanniae- ~ hardground or 1 Kamerunoceras ganuzai ~ incipient hardground 1;::I::;;t;t;;;:~:J;~,cortestudinarium r- --- Romaniceras deverianum b---I hiatus conglomerat ------SUbprionocyc. [D> hiatus neptuni Inoceramus costellatus deverianum/ _ rh Ie r------,.-..----, ~l Hg oJ-~R~.-d~~--nmw~·~m~-r--~ Inoceramus striatoconcentricus Tongoboryoceras v --' 2 1------1- Cremnoceramus waltersdorfensis 4 ,...... ,,~~_-J Cremnoceramus rotundatus 6 1; -o;,;aiiss;;W~ -:- -- z R. kailesi- « ------Z 0 ALSASUA KB11lerunoceras ~ ~ Eo< turoniense ~ e I HamJIlites «Z nodosoides / Z 0 Kamerunoc:eras ~ ~ ganuzai Eo< ~ tll ~ 0 ...J - - -- z :sz « ::;; geslinianull o @ u -.---- '-~ KUCHLER 6km ------+------19km----~------7 km------4 Event correlation within the Barranca; east-west transect from eastern, swell located (Arardi and Izurdiaga) to basinal (Itunnendi and Alsasua) sections in the west; the latter sections investigated microstratigraphically by ZANDER (1988) UPPER CRETACEOUS OF THE BARRANCA 177 tempestites seem to be caused by the simultane KAUFFMAN (1986) listed among the possible ous building of the coast and wave erosion, e.g. causes of the bio-events, rapid extinctions, immi during the late highstand and early lowstand. grations, changes in popUlation size and coloni The event stratigraphy developed by ERNST & sations. However, distinction between the bio al. (1983) in the Cenomanian and Turonian of logically caused events and the events caused by NW Germany additionally refers to the so-called physical or chemical phenomena is rather diffi stratigraphical events, classified into eustato-, cult as both types can grade one another. eco-, tephro-, litho-, phy 10-, and oxic/anoxic In addition, the first and last appearances of events, and interpreted as genetically distinct. In biostratigraphic index taxa, at species or sub contrast to pure sedimentological events, the ori species level are described as bioevents. In event gin of stratigraphical events involved markedly stratigraphical terms such an interpretation is not longer periods, up to several tens of thousand followed here. The record of a species or sub years. Stratigraphical events can be treated, how species in a particular area depends on many dif ever, as comparatively short-lived and isochro ferent factors controlling dispersal, as well as on nous horizons, that of markedly shorter duration fossilisation and sedimentary processes, so that than the standard ammonite zones which, in the the observed distribution and stratigraphical Turonian for example had a duration of between range may reflect only a part of the hypothetical 400 000 and 500 000 years (see ROBASZYNSKI & total range. However, most local range records al. 1990, HANCOCK 1991). The genesis of an are incomplete and the first and last appearances event is usually multi-causal and a sharp distinc in different sections are hardly ever isochronous. tion of the particular event-types is usually In their original paper ERNST & al. (1983) indi impossible. The origin of events is highly com cated the inter-relation between the bio- (eco-) plex, involving the interaction of a multiplicity of events and relative changes of sea-level. Under factors, as emphasised by KAUFFMAN (1986). In the term eustatic-event they united both, negative his high resolution event stratigraphy developed (regressive) and positive (transgressive) sea for the Western Interior Cretaceous he distin level fluctuations, giving a set of criteria for their guished physical, chemical, thermal and biologi recognition. The distinction between transgres cal events. Among the most common events he sive and regressive eustato-events will be fol listed are tuffs, mass flow deposits, oxygen over lowed here, as far as possible. Those sea-level turns, desalination events (caused by giant storms changes that are interpreted as the result of plate in the shallow basins), boundaries of the tectonic movements, are referred to here as tecto MILANKOVITCH cycles, mass mortalities, and eustatic events. Many tectonic processes (culmi mass extinction events. The application of event nation of active phases) take place within a mil stratigraphy here permits stratigraphical resolu lion years, some even, within a few tens of thou tion far below the interval of a biozone with an sands of years. The accompanying changes in the average duration of 50000 years. bathymetric and sedimentary conditions take The event stratigraphical scheme presented here place very rapidly. Most of the tecto-eustatic for northern Spain (see also ERNST & KOCHLER events thus correspond well to the sequence 1992) was developed independently of the north boundaries (in the sense of HAQ & al. 1987). German scheme (see ERNST & al. 1983, WOOD & Some of these tecto-events, correlatable through al. 1984, KAPLAN 1986) and of the event succes out Europe were already referred to by ERNST & sion later established for the Santander area KOCHLER (1992). The position of bio-events (WILMS EN & al. 1996, WIESE 1997). within a 3rd order sea-level cycle was recently The event types, described below, are used in shown clearly by WIESE (1997) and WILMSEN the sense of ERNST & al. (1983), and are defined (1997). Events crossing structural highs, so here as relatively thin intervals in a dm to m scale called overlapping events, coincide with maxi commonly characterized often by a succession or mum flooding surfaces and represent the pri'mary a bundling of subordinate, short-lived phenome isochronous correlation horizons within areas na. In the Turonian of northern Spain, these sub that are strongly differentiated into swells and ordinate, minor events are represented mostly by basins. The state of the art of the microfacies and ammonite or inoceramid accumulations. These sequence stratigraphical studies in the Barranca are referred to here as bio-events with, at the do not allow for any comprehensive interpreta moment, no genetic interpretation. tion at the moment. Consequently, the present 178 THOMAS KUCHLER paper is limited to a description of the event beds, 0.65%). The horizon is expressed in the Alsasua their phenotypic characteristics, faunal composi section (road cutting on the N-240 2.2 km north tion and lateral changes in respect of the basin of Alsasua), 25 km distant, by an horizon in configuration. The event succession is shown argillaceous marl with a slightly increased Cor" within an already high resolution biostratigraphi content (TOC = 0.83%) (see Text-fig. 11). To the cal scheme, allowing direct dating (see Text-fig. east, the equivalent level in the Arardi section 10). The Turonian succession was first worked still shows ca. 0.45% TOe. out in the condensed sections of the outer shelf of In comparison with COla content of the the Barranca and then recognized and tested Bonarelli Event, Italy, depo;ited in ca. 1 km within the sections of the Estella area. depth on the continental margin, with TOC val ues between 11.8 and 23.0%, or with the English Oceanic Anoxic Event Black Band with 1.0 to 1.5% values, or with the 1.2 to 2.8% TOC values in the black shales of The oceanic anoxic event (OAE) is clearly Wunstorf, Germany (compare SCHLANGER & al. manifested in the Satrustegui section in bed 75 1987), the black marl band of the Barranca does which is referred here to as the black marl band. not display a significant Cora content. However, In general, it is a more extended, 1.1 to 2.2 m the black marl band of the B;rranca does not cor thick interval of calcareous marls, marls or respond stratigraphically to those in Italy or clayey marls with a slightly increased TOC England. The latter two are placed in the Upper (=total organic carbon) content. In the Barranca Cenomanian - Lower Turonian Whiteinella (Text-fig. 10), the black marl band is traceable archaeocretacea Interval Zone, while the hori from the Satrustegui section, where in bed 75 it zon in the Barranca, according to ZANDER (1988, reaches maximum 0.91 % TOC, 19 km towards p. 35), belongs to the Helvetoglobotruncana the west to the cemetery section of ZANDER [Praeglobotruncana] helvetica Zone of the (1988), 500 m north of Iturmendi (TOC = upper Lower Turonian. GRAFE (1994) quoted a ARARDI ~ oz Kamerunoceras ~ ;:. turoniense E-< :::::::::::::::: ::::: z ;::s Z Kamerunoceras ~ ganuzai/ ~ Mammites nodosoides Fig. 11. Correlation of the reveliereal1l1s and turol1icnselherc),nicus events between thc Arardi and Izurdiaga II sections; stratigraphical ranges of selected ammonite and inoceramid forms UPPER CRETACEOUS OF THE BARRANCA 179 similar stratigraphical posltlOn for genetically zai/nodosoides (=Mammites nodosoides) and the equivalent deposits in the Province of Alava Kamerunoceras turoniense zones and is associated (GRAFE] 994). with yet another Mytiloides-acme. In the Izurdiaga and Arardi sections, the event is marked by a fre Kamerunoceras ganuzai Event quency maximum of Mytiloides labiatus within a 1 m thick limestone bed at the top of a thickening Actually, this event represents a bundle of upward sequence (see Text-fig. 11). This level is closely in time spaced subordinate events, i.e. most probably condensed in the eastern Barranca, several ammonite and inoceramid layers, occur yielding only a comparatively sparse ammonite ring in a restricted stratigraphical interval (see fauna (mainly juvenile S. reveliereanus), compared Text-fig. 3). It lies in the middle part of the with the rich faunas of the Ganuza section in the f.!,anuzailnodosoides Zone of the upper Lower Estella Basin. The horizon represents a local over Turonian and takes its name from the ammonite lap of late forms of M. nodosoides (M. cf. species Kamerunoceras ganuzai (WIEDMANN), nodosoides) and the first K. turoniense. which first become common at this horizon and At Satrustegui, in a more basinward position, locally dominates the fauna. In addition to an the event is marked similarly by a M. labiatus abundance-acme of ammonites the event is char -acme (Text-figs 7-8), but ammonites are acterized by a second, locally developed extremely scarce and mostly represented by Mytiloides-acme. The first Mytiloides-acme, gaudryceratids and phylloceratids. Near represented by the Mytiloides I Event, is missing Satrustegui, the m thick marly limestone horizon in the Barranca probably as the result of faulting. developed in the more the eastern sections passes In northern Spain the ganuzai Event has been into a double limestone bed, each with a recognized up to now in Navarra, namely in the Mytiloides layer. Arardi section and near Ganuza in the Estella area. The base of the ganuzai Event is the first Kamerunoceras turonienseiMytiloides correlation horizon between both areas. In the hercynicus Event eastern Barranca the ganuzai Event is absent near Izurdiaga and Satrustegui as a result of tec This event comprises an event-bundle, which tonics. The event, in the form of a fossil accumu in one extreme is characterized by a mass-occur lation is also not traceable to the western rence of ammonites (particular kameruno Barranca. In the Arardi section, the event, devel ceratids, sciponoceratids, and spathitids) and in oped as 1.1 m thick limestone/marl alternation, is the other by the highest frequency maximum of characterized by an ammonite assemblage domi Mytiloides hercynicus. It lies in the middle part nated by S. cf. bohemicum. In contrast to the of the K. turoniense Zone. It comprises essential Estella area, the index taxon, K. ganuzai is much ly two limestone beds with an intervening marly less common. Its occurrence is limited to the interval, in a total thickness of 0.7 to 0.8 m. It basal limestone bed, where it co-occurs with S. mainly yields inoceramids, and thus defined, is cf. bohemicum, M. mytiloides and representa traceable from the marginal swell sections of tives of the M. labiatus group. In the upper part Arardi and Izurdiaga over 7 km towards the west of the event, occur several horizons with S. cf. to the more distal, basin word Satrustegui section bohel11icum and M. labiatus, while an abun (Text-figs 9-10). In the fomer sections the turo dance-maximum of diverse Mytiloides species niense/hercynicus Event contains a relatively found at the top of the succession. In addition to diverse ammonite fauna (see Text-figs 5, 11). the predominant M. labiatus and M. aff. hercyn The associated inoceramid fauna for the first icus the assemblage also contains rare M. aff. time contains unequivocal M. hercynicus, as well duplicostatus and M. aff. mytiloides. as late M. labiatus, with the latter dominating in the Barranca, while in the Estella area the inoce Spathites reveliereanus Event ramids are represented exclusively by M. hercyn icus and M. cf. hercynicus (Text-fig. l8). The The event is marked by an acme of representa typical development of the event is exemplified tives of the ammonite genus Spathites, primarily S. by the lzurdiaga I and II sections (Text-figs 4,5) (Jeanrogericeras) reveliereanus (COURTILLER). It where a succession of characteristic fossil accu lies m the transition between the ganu- mulations is observed: 180 THOMAS KUCHLER Just below the event lies a 0.6 m thick inter MTE (Middle Turonian Event) val, composed of two limestone beds separated by a thin marl seam, which contains a fauna This is an eustatic, transgressive event at the mainly composed of ammonites and dominated boundary of the Romaniceras kallesi and by Kamerunoceras turoniense. The mostly Romaniceras ornatissimum ammonite zones, or completely preserved steinkerns of K. tur at the boundary of the Helvetoglobotruncana oniense represent the ribbed, salmuriense type helvetica and Marginotruncana schneegansi (PI. 7, Fig. 2). The event beds (IzII-93 to IzII-96 foraminiferal zones. The event lies within a and IzI -42 to IzI -46) are characterized either by series of pelagic hardgrounds that occur through the predominance of Sciponoceras or by the out the Barranca, from Izurdiaga to Alsasua (see occurrence of inoceramids. These occur in accu Text-fig. 10) (ZANDER 1988) and represent mulations at the top of the limestone beds or reduced sedimentation of the R. kallesi and R. within the marly beds. The lower 0.4 to maxi ornatissimum zones. In the eastern Barranca the mally 0.75 m of the event interval contain a MTE is clearly expressed by a thin, 0.05 to diverse ammonite assemblage, comprising 0.10 m thick horizon with intraclasts, which lies Kamerunoceras turoniense, K. ganuzai, in the R. ornatissimum Zone, within a series of Spathites reveliereanus, Spathites sp., Pachy erosionally truncated Thalassinoides hard desmoceras denisonianum, Pachydesmoceras grounds (Text-fig. 5). The intraclast horizon, sp., Fagesia aff. catinus, Sciponoceras cf. locally called the kallesilornatissimum Event, bohemicum, and N. (Eubostrychoceras) sp. The yields reworked ammonites of both zones, indi ammonites occur mostly within the marly beds cating a small hiatus. and are accompanied by M. labiatus and subor dinate M. hercynicus. Within the marls there is Romaniceras ornatissimum Acme an intercalated allochthonous nodular limestone bed (packs tones with "calcisphere" wackestone In the Izurdiaga section, Romaniceras ornatis intraclasts) with fragmentary, large-sized K. tur simwn occurs commonly in an about 3 m thick oniense and also pachydesmoceratids. The for interval in the lower part of the R. ornatissimum mer are strongly tuberculate and represent Zone (middle Middle Turonian). In the Arardi inflated forms of the turoniense type (Pl. 7, Fig. section the equivalent interval is lacking due to a 3). Large-sized Pleurotomaria are also a strik tectonic gap, and in the Satrustegui section it is ing feature. This rich allochthonous fauna repre absent because of a stratigraphical gap. The R. sents a taphonomical trap giving an insight into ornatissimum-acme probably represents an eco the ammonite fauna of the unexposed proximal event of the highstand systems tract. facies. The event-bundle terminates in a lime stone bed with M. hercynicus and Sciponoceras LUTE (Lower Upper Turonian Event) sp. In the Arardi section, to the east, (Text-fig. 3) the equivalent interval, 0.7 m thick, is repre This is a tectonic event of inter-regional impor sented by two limestone beds (Ar-70 and Ar- tance that probably comprises several short-term 71), with Mytiloides ex gr. labiatus and subor events, which in northern Spain falls in the lower dinate M. hercynicus. The impoverished Upper Turonian (Subprionocyclus neptuni ammonite fauna consists of a few juvenile Zone). In swell sections, the LUTE is recorded spathitids. In more distal positions, i.e. in the by one or more hiati in the interval between the Satrustegui sections (Text-figs 6-8), one can upper deverianum and upper neptuni zones observe a clear lateral change in the ammonite (Text-fig. 3). It is expressed by conspicuous shal fauna, compared with that of the marginal swell low marine hardgrounds with a locally intercalat sections, towards more pelagic forms and a pre ed transgressive conglomerate (Arardi section) dominance of pachydesmoceratids. The sparse and re-worked ammonites or, in more distal posi ammonite fauna is represented by Sciponoceras tion (Izurdiaga section), an ammonite horizon sp., S. bohemicum, Pachydesmoceras sp., (deverianumlrhodanicum Bed) (Text-fig. 5) with Phylloceras (Hypophylloceras) sp., Gaudry Middle and Upper Turonian ammonites, primari ceras sp., and ?Prohauericeras sp. Rare inoce ly desmoceratids. The pre-LUTE beds in the ramids (M. hercynicus and M. subhercynicus) Izurdiaga section and, particularly, at Arardi do also occur. cument a polyphase hardground development. UPPER CRETACEOUS OF THE BARRANCA 181 The succession starts with a Thalassinoides fir Micraster ex gr. normanniae-cortestudinarium mground, succeeded by a glauconitized hard Event ground, and terminated by phosphatization and partial colonisation by oyster-like bivalves and The first abundance-maximum of Micraster ex serpulids. The succession represents a shallow gr. normanniae - cortestudinarium lies at the ing-upward cycle or a phase of active tectonic base of the herein introduced C. waltersdorfensis uplifting. Zone. Because of stratigraphical gaps, this event The conglomerate from the Arardi section is recognizable in the Barranca only at Izurdiaga forms a thin horizon of bored and phosphatized (bed IzI-97) (Text-fig. 5). flat pebbles with glauconitic crusts and encrust ing organisms (oysters and serpulids). It is fol lowed by a 0.1 m thick horizon penetrated by Ammonite/Inoceramid zonation in the phosphatized and glauconitized Thalassinoides Barranca burrows and terminating in a hummocky hard ground. This horizon yields numerous phospha The biostratigraphy of the Lower and Middle tized and reworked ammonite steinkerns, main Turonian of the Barranca is based primarily on ly juvenile Tongoboryceras, corroded echinoid ammonites, and partly on inoceramids. tests (Conulus subrotundus), as well as rare The correlation with the scheme established by inoceramids and other bivalves. In a more bas WIEDMANN (1960, 1965, 1979a, b) for northern inward position (e.g. Izurdiaga section) an Spain is indirectly possible only in the upper ammonite horizon occurs within the hardground Middle Turonian (from the Kamerunoceras tur sequence containing predominantly R. de oniense Zone up to the Romaniceras deverianum verianum and Romaniceras sp., together with Zone). The ammonite species used by that author Puzosia sp., Puzosia muelleri and Tongobo in the zonation of the Upper Cenomanian and ryoceras sp. Lower Turonian, are Tethyan or endemic forms, SUBSTAGES France Spain Europe SUBSTAGES LOWER CONIACIAN Forresteria petrocoriensis Forresteria petrocoriensis Forresteria petrocoriensis LOWER CONIACIAN 11111111111111111111111111111 waltersdoifensisl germari UPPER Subprionocyclus neptuni UPPER Subprionocyclus neptuni Subprionocyclus neptuni TURONIAN TURONIAN Romaniceras deverianum Romaniceras deverianum Collignoniceras MIDDLE Romaniceras omatissimum Romaniceras omatissimum MIDDLE woollgari TURONIAN Romaniceras !mllesi Romaniceras !mllesi TURONIAN Kamerunoceras turoniense Kamerunoceras turoniense Kamenmoceras ganllzai! Mammites nodosoides Mammites nodosoides LOWER Mammites nodosoides LOWER TURONIAN IIIIIIIIIIIIIIIIIIIJJW Watinoceras coloradoense TURONIAN III hiatus I hiatus, ...... lill"""I'~""""""1111 ~ •• unnamed Neocardiocerasjuddii Neocardiocerasjuddii UPPER --_ ... _...... ------... ------UPPER (unnamed Thomasites fauna) CENOMANIAN CENOMANIAN Metoicoceras geslinianum Metoicoceras geslinianum Metoicoceras geslinianum Fig. 12. Comparison of European Upper Cenomanian-Lower Coniacian ammonite schemes and positions of formally used substage boundaries; after AMEDRO & al. (1982) and ROBASZYNSKT & al. (1982) for France, KOCHLER (this work) for northern Spain, and KENNEDY (1984 b,1985); the Spanish ammonite zonation, established by WTEDMi\NN (1960, 1965, 1979a), is discussed further on (see also Text-fig. 17) 182 THOMAS KOCHLER that are mostly absent in Navarra, while some of Estella area (compare KOCHLER & ERNST 1989), his zonal indices appear markedly earlier than as well as in the Santander region (WIESE 1995, formerly assumed. Consequently, his zonation 1997). This is particularly the case with the K. cannot be applied to the Barranca. turoniense Zone, because of the widespread and The ganuzailnodosoides Zone, introduced here common occurrence of the index taxon. In the for the upper Lower Turonian does not corre basal part of the zone K. turoniense co-occurs spond to the Schindewolfites ganuzai Zone with late M. nodosoides, while at the top of the established by WIEDMANN (1960, 1965, 1979a) in zone transitional forms to R. kallesi are found. the Estella area and subsequently used for the The biostratigraphical zonation of the Upper Lower Turonian of northern Spain. WIEDMANN Turonian in the Barranca, because of the rarity of treated the local range of S. ganuzai as an equiv ammonites, has had to be based on the similarly alent of his regional zone TU -IV, i.e. the Zone of rare inoceramids. Through faunal comparison Ingridella malladae and Schindewolfites spp., with the Estella area, with its rich ammonite which was, on the other hand, perceived as the fauna, the zonation of the Barranca can be corre upper part of the Mammites nodosoides Zone lated indirectly with the NW German zonal (compare WIEDMANN & KAUFFMAN 1978, schemes, both that based on ammonites (see WIEDMANN 1979b, KENNEDY 1985). The restudy KAPLAN 1986, 1988) and that based on inoce of WIEDMANN'S type locality demonstrates that ramids (KOCHLER & ERNST 1989, Text-figs 7-8). his ganuzai Zone corresponds to the upper part of the ganuzailnodosoides Zone. In the Estella The Cenomanian/Turonian boundary interval region the species is known only from the Lower Turonian, apart from a questionable find reported The topmost Cenomanian and basal Turonian, by LAMOLDA & al. (1989), together with in the sense of the currently applied ammonite Romaniceras kallesi. It ranges, however, into the biostratigraphy, are missing in the Barranca. The lower Middle Turonian in the Barranca, where it Upper Cenomanian Metoicoceras geslinianum co-occurs with K. turoniense. In the ganu Zone cannot so far be proved by means of zailnodosoides Zone, K. ganuzai is in general ammonites. This zone is, however, suggested by rather rare, while it is relatively common in the a single find of Inoceramus pictus bohemicus following zone. LEONHARD from the top part of the Cenomanian The collignoniceratids, especially Collignoni limestones - calcareous marl alternations in the ceras woollgari (MANTELL), the index ammonite Arardi section, since this species, according to species for the base of the Middle Turonian in TRaGER (1989) and WIEDMANN & al. (1989) has north-west European sections (see Text-fig. 12) its main occurrence interval in the M. geslini are extremely rare in this interval in the Barranca anum and Neocardioceras juddii zones. and in northern Spain in general. As in France, There is also no evidence so far of the presence this species first appears very much later. In con of the N. juddii and Watinoceras coloradoense sequence, the application of the standard zones, or their Iberian equivalents, i.e. the ammonite zonation for the Middle Turonian of Vascoceras gama!, Fallotites subconciliatus and NW Europe (sensu WRIGHT KENNEDY & al. 1982 Paramal11l11ites? saenzi zones, sensu WIEDMANN. and KENNEDY 1984b, 1985; compare also The interval is characterized by the hiatus widely HANCOCK 1991), i.e. the recognition of a C. recorded in Europe at the Cenomanian/Turonian woollgari Zone in the sections of northern Spain transition, which was already recognized in the is not possible. On the other hand, marked faunal western Barranca by RAMIREZ DEL POZO (1971) similarities in the Lower Turonian and particular by means of planktonic foraminifera. ZANDER ly in the Middle Turonian between northern (1988) was able to determine the extent of hiatus Spain and the French Turonian type regions precisely in the Iturmendi section. The gap here, (Touraine and Saumurois) enable the application probably of the same extent as near Alsasua, of the refined zonation of AMEDRO & al. (1982) comprises the upper part of the Rotalipora cush based on the Kamerunoceras - Romaniceras lin mani Zone, characterized normally by solely eage. The French ammonite zonation, comprising occurring R. cushmani, as well as the entire the K. turoniense, R. kallesi, R. ornatissimum, Whiteinella archaeocretacea Zone. According and R. deverianul11 zones (see Text-fig. 12), is to ZANDER (1988), the cushman! Zone is fol readily applicable in the Barranca and in the lowed directly by the upper Lower Turonian UPPER CRETACEOUS OF THE BARRANCA 183 Helvetoglobotruncana helvetica Zone. A gap, from that given by ROBASZYNSKI & al. (1990) for with a more or less similar stratigraphical range Tunisia, defined by the last appearance of is also postulated, based on the available fossil Mal11l11ites nodosoides. The base of the zone is data, for the eastern Barranca. The first evidence additionally marked by common Spathites reve for the Turonian there is provided by transitional liereanus (see PI. 6, Figs 4, 6) and late forms of forms between Inoceramus and Mytiloides in the Mal11mites cf. nodosoides (see PI. 6, Fig. 5). The Arardi section, with unequivocal Early Turonian lower part of the zone is dominated by S. reve ammonites occurring in a few metres higher. liereanus, Sciponoceras bohemicum and Pachydesmoceras denisonianwn. In the upper Kamerunoceras ganuzailMammites nodosoides part, in the proximal areas (Arardi and Izurdiaga Zone sections), the zone is characterized by a rich and taxonomically diverse ammonite fauna dominated The base of the zone is defined by the first by kamerunoceratids (K. turoniense and appearance of the small-sized, spinose acanthocer K. gamlzai) and spathitids (s. reveliereanus). In atid Kamerunoceras ganuzai (WIEDMANN). This distal areas the ammonite assemblage is dominated species occurs relatively commonly in the Lower by P. cf. denisonianul11. Co-occurring forms are S. and in the lower Middle Turonian of northern bohemicum, S. cf. bohemicum, rare Nostoceras Spain. At Ganuza, its type locality, according to (Eubostrychoceras) aff. matsul11otoi (COBBAN) LAMOLDA & al. (1989), K. ganuzai appears si (see PI. 7, Figs 6, 8-9), and N. (Eubostrychoceras) multaneously with Mammites nodosoides sp., Placenticeras aff. cumminsi CRAGIN (see PI. 7, (SCHUlTER). Because of the extreme rarity of the Fig. 1), Cibolaites molenaari COBBAN & HOOK latter species in northern Spain, particularly in (see PI. 6, Fig. 7), Fagesia aff. catinus (MANTELL), Navarra, at least in the lower part of its range, the Puzosia cf. planata (BAYLE), and Neoptychites ganuzailnodosoides Zone is proposed as an cephalotus (COURTILLER). In distal deposits equivalent of the international M. nodosoides Gaudryceras sp., Phylloceras sp., Phylloceras Zone. In the Barranca (Arardi section) K. ganuzai (?Hypophylloceras) sp., ?Lewesiceras sp., and appears for the first time in the so-called ganuzai Tetragonites sp. appear. Event which, in comparison with the FAD of this species at Ganuza, in the kossmati Event (com Romaniceras kallesi Zone pare Text-figs 14, 16), lies in the middle part of the zone. In the Arardi section (Text-fig. 3), K. Both this zone and the succeeding R. ornatissi ganuzai (PI. 5, Figs 9-10) occurs in the ganuzai mum Zone are extremely condensed in the east Event together with Sciponoceras cf. bohemicum ern Barranca. In the Arardi section the presence (FRITSCH) (PI. 5, Figs 5-6). An extremely rare of the kallesi Zone is presumably indicated by ammonite fauna was found in the basal, 4 m thick Romaniceras aff. kallesi (ZAZVORKA) (see PI. 8, part, of the Izurdiaga II section (which is not the Fig. 2) and fragmentarily preserved Romaniceras base of the zone), comprising Spathites (J.) robus cf. kallesi in a single horizon. Near Izurdiaga the tus (WIEDMANN) (see PI. 5, Fig. 7a-b), zone is 2.1 m thick, but the index species is Choffaticeras quaasi (PERON) (see PI. 9, Fig. 8a extremely rare below the kallesilornatissimum b), Pachydesmoceras sp., and Spathites (J.) reve Event. Its range there overlaps with that of liereanus (COURTILLER). Slightly higher appears K. turoniense. Spathites (Ingridella) malladae (FALLOT) (see PI. 5, Fig. 8a-b), and still higher K. ganuzai. The top Romaniceras ornatissimum Zone most part of the zone is characterized by a sole occurrence of Pachydesmoceras denisonianum The index species Romaniceras (Yubariceras) (STOLlCzKA)(see PI. 6, Fig. la-b) and Spathites ornatissimum (STOLICZKA) (see PI. 8, Figs 1 and (1.) reveliereanus (COURTILLER). 3) is only locally common. At Izurdiaga, it is found together with R. kallesi in an 3.5 to 4 m Kamerunoceras turoniense Zone thick interval, but it has not so far been found in the Arardi section. In the latter section, the pres The base of this zone is defined here by the first ence of the zone is indicated by the first appear occurrence of K. turoniense (O'ORBIGNY) (see PI. ance of Tongoboryceras sp., accompanied there 6, Fig. 2; PI. 7, Figs 2-5). This definition differs by ?Kamerunoceras sp. and Puzosia sp. 184 THOMAS KUCHLER Romaniceras deverianum Zone STANDARD SECTIONS IN THE ESTELLA AREA The index species was reported from the Izurdiaga section by KUCHLER & ERNST (1989), Near the villages of Ganuza and Ollogoyen, thereby proving the presence of the zone in the about 10 km west of Estella, are found several Barranca. Accompanying forms are represented sections, which have been intensively studied for by Tongoboryceras sp., Pachydesmoceras decades, and regarded as standard sections for denisonianUln, Puzosia sp., and Puzosia cur the Turonian in northern Spain. Multidisciplinary vatisuicata CHATWIN & WITHERS. However, the investigations supplying important data were position of the base of the zone in the Izurdiaga undertaken by WIEDMANN (1960, 1965, 1979a), section, defined by the FAD of the index taxon is WIEDMANN & KAUFFMAN (1978), LAMOLDA & al. questionable, since there is a 7.4 m thick interval (1981), SCHWENTKE & WIEDMANN (1985), without unequivocal R. deverianum and without LAMOLDA & PROTO-DECIMA (1986), LAMOLDA & any other stratigraphically important ammonites. al. (1989), KUCHLER & ERNST (1989), LOPEZ R. deverianum (see PI. 8, Fig. 4) appears for the (1990, 1992a, b, d), SANTAMARIA (1991, 1992, first time in the deverianum/rhodanicum Event 1995) and LAMOLDA & PERYT (1995). at the top of the zone. In the Arardi section the The Ganuza section provides a continuous suc so-called deverianum/rhodanicum pebble bed cession across the Cenomanian-Turonian bound contains already a mixed ammonite association ary developed in silty limestone facies. Compared composed of Middle and Upper Turonian forms, to the English Eastbourne and Dover sections or but without R. deverianum. The R. deverianum the American Pueblo section, the Ganuza section Zone is indicated only by the presence of represents the most expanded and complete Tongoboryceras rhodanicum (ROMAN & boundary succession according to LAMOLDA & MAZERAN), occurring here associated with PERYT (1995). Near Ganuza, the exposures extend Puzosia sp. and juvenile Tongoboryceras sp. up into the Middle Turonian (Romaniceras kalle si Zone). Near Ollogoyen, an exceptionally thick Subprionocyclus neptuni Zone succession of Middle Turonian to upper Upper Turonian (R. deverianum Zone up to the The presence of the zone is documented in the Cremnoceramus waltersdorfensis/Prionocyclus Barranca by single finds of Baculites undulatus germari Zone) is exposed, albeit not reaching the D'ORBIGNY (see PI. 8, Fig. 5) and Neocrioceras Turonian/Coniacian boundary (see KUCHLER & (Schlueterella) cf. multinodosum (SCHLUTER), ERNST 1989). together with Inoceramus costellatus WOODS To the south the Estella area is limited by the and Mytiloides striatoconcentricus (GUMBEL) in Villasana de Mena-Estella Diapir Zone and to a single horizon in the Arardi section. Such an the east by the Estella-Dax Diapir Zone. During association is typical for the neptuni Zone. The the Late Cretaceous the area was situated in the index taxon of the zone, S. neptuni (GEINITZ) and south-easternmost part of the Navarro also Subprionocyclus ex gr. neptuni - hitchinen Cantabrian zone of intra-shelf basins, within a sis, are lacking in the Barranca, most probably halfgraben or oblique-slip-fault basin, with the because of the more distal location of this area. greatest subsidence at its southern margin (WIEDMANN 1979a, REITNER & WIEDMANN Cremnoceramus waitersdorfensis Zone 1982). During the Cenomanian and Turonian the Estella Basin was characterized by a high subsi The base of the zone is defined by the FAD of dence and sedimentation rate with the resulting C. waltersdOljensis (ANDERT) in the MiCl'aster accumulation of a 1200 m thick succession. ex gr. normanniae-cortestudinarium Event at During the Middle and Late Turonian the whole Izurdiaga. The zone is documented only by area lay in the mid-shelf, with predominantly scarce and poorly preserved inoceramids. open-marine, partly nerItIc conditions. Besides the nominate species Inoceramus web Accumulation and subsidence rates were in equi steri sensu WOODS also occurs. Despite the rarity librium at least in the Late Turonian. The distri of ammonites the zone is assumed to correspond bution of the benthonic foraminifera and the approximately to the Prionocyclus gennari Zone composition of the assemblages, i.e. lack of of authors. shallow marine or extreme deep-water indices, UPPER CRETACEOUS OF THE BARRANCA 18S indicates, according to LAMOLDA & PROTO II (GI), located west of the national road DECIMA (1986, Text-fig. 3), a not particularly Ollobaren - Ganuza, south and south-west of the deep environment. village of Ganuza. The thickness of the exposed Turonian in the composite Ganuza/Ollogoyen standard section is about 230 m, of which 130 m Ganuza Section (upper Cenomanian are exposed close to Ganuza. to Middle Turonian, kallesi Zone) Canuza IV (CZ) The Ganuza section (see Text-figs 13-14) is composed of the three investigated exposures, Location: Topographical map Metauten, sheet i.e. Ganuza IV (GZ), Ganuza I (GA) and Ganuza 140-13,1:10000, R=S70.940, H=4.727.4S0. \..... / : t \ 1"", : I \ f I I ,I If Fig. 13 Location of the Ganuza and Ollogoyen sections, J 0 krn west of Estella 186 THOMAS KUCHLER .. NVINOlIfl.l 3"'1aarW i+ lI3".M.O'1 .. "J-"' • i!! ~ ~ = 0- ~ '" .Jl! " 0-'" .s" I .!!! ~ ~ ~ £ ~ B~:§ !rw I ...J g ~~~ ~ I .E =r:::: E E 0 '::J il r-~ ~ N >< - ai CO ;!? • • U U f- a> '"~ III a; on z ;!? 0' , '"a:: C!- w .. « "E ... 1;; fi 0" « « - E §'" Effi 0 :; ~ E ...J « 0 .0 ,gf 0 f- f! :; Z " '" ~,g « • 0>< :5 en •• E § §; '" ~ § .... <' U S, I =""" .: 1 0'" "I ;;:/<)0 ( ( ( ( ( ( sap!osopOU saJ!wulIJW ···············-{-················:····I""" 1m .:•.•.• :. II !vznuvg sv.Ia:Joun.lawv)j .•. Isvvnb SV.laa!Jv.f!0/f:J l.la!llltl1Jd SV.la:J!JvjJo/f:J i.":: :'::': 1 sn:J!qvlnOlf-s!suanguog!PUVll°.l 'p saI!SVw0/.f.L 'jjj 'ds :L 1...... ' ..... 1:.':':;;("IL.. , ...... 1 I...... ::::~.. ·:j I,' 'ds v!sagv!!",YH(~ *-.·.:.. V.lpnJ '1Jll o!sagv,d 1':: sapfO:JSlpif/f:Jod '10 v!sagv,d I::::' I.. :d snUvaJa!latla.l '10 saJ!l.{Jvds r·· snuvaJallatla.l saJ!/fJod,,<;; I· .... ···········',·· .. ·I[I:-:··:::I::::::::::i· .. '·· .. •••••••••• •• ··············*:::.,WlI--.,iM snnb!lqo saJ!/f/vdS 1•...... ' ..... 1..':,,: ••::, .. ;".+ .. , ....•....•..•.••...... 1'p: ..-I+. --!III !%wns/vw '1Jll (so.la:J0/f:JifJ/soqng) N ...... + ...... +... +,../"." .. +...... • ~- •• wn:Jlwa/foq SO.liJ:JouodPS ,...... "'1 !su!wwn:J 'JJll SV.laa.1JUiJ:Jvld '... :';::::':""41 1 asualuo.lnJ SVJaaounJawv)j ...... Ei}i:::'::: ---. ,:':,:,:: .:".1.j lsallolf SV.la:J!UVWON I:: Ii: .: 'dds SVJa:Jowsapifrpod wnUO!SV!.lnalj SVJaa!J/u!o:Jal ...... "." ...... 1"1 ...... , .. "'1//+ .... 1;. ;:: '" " ~ " il "... ,. .~ ~ >il" ~ "... "g, Fig. 14. A - Lithologic-stratigraphical columns, events, ammonite ranges and inter-correlations of the Ganuza sections; the investigated exposures correspond to the Ganuza IV (GZ), Ganuza I (GA) and Ganuza II (GI) sections sensli SANTAMARIA (1991, 1992) and LOPEZ (1990, I 992d); B - WIEDMANN'S (I 979a) ammonite zonation of the Ganuza section (modified) ACTA GEOLOGICA POLONICA , VOL. 48 T. KOC HLER , PL. 3 Lower-Middle Turonian succession near Ganuza 1 - Ganuza II (GI) section; view from N to S; ex posed is a succession from the upper Lower Turonian (ganuzailnodosoides Zone) up to hi gher Middle Turonian (ornatissimum Zone); the top limestones of unit C2 are covered up to the Middle Coniacian limestones (cliffs of the Sierra de Santiaga de Loquiz) by ta lu s; 2 - Erosional channel of the Ganu za I (GA) section; visibl e the GA-3 and GA-4 beds (interval of the reveliereanus Event) exposed west of the track Ganuza-Ollogoyen; 3 - Close-up view of the GA-4 limestones marked in Fig. 2 UPPER CRETACEOUS OF THE BARRANCA 187 The interval compnslllg the Upper Ceno iatus (CHOFFAT) (assigned to the Watinoceras manian through the Lower Turonian starts ca. coloradoense Zone by LAMOLDA & al. 1989, 600 m south of the centre of Ganuza, east of the Text-fig. 2 in the same section), there is no evi national road, with a succession marked as GZ. It dence for an Lower Turonian in this particular corresponds to the GZ section of LAMOLDA & al. part of the section. The faunal association sug (1989) and to the Ganuza IV (GZ) of gests WIEDMANN'S TU-III Zone (zone with SANTAMARIA (1991, Text-fig. 10). The bed num Leoniceras discoidale). Referring to WIEDMANN bering used here is adopted from that of the latter (l979a, Text-fig. 10), this interval above the author. The top of the section is situated ca. 350 track lies actually in his TU-III Zone, which does m SSW of Ganuza, within the track leading to the not correspond to his basal Turonian. Church. Lithostratigraphy Ganuza I (GA) With slight modification of the notation of the Location: Topographical map Metauten, sheet units (see Text-fig. 14), the descriptions here are 140-13,1:10 000, R=570.750, H=4.727.440 taken from LAMOLDA & al. (1989). Accordingly The composite Ganuza section continues in an in the whole Ganuza/Ollogoyen section, nine erosional gully, above the track, ca. 600 m SSW lithological units are distinguished. These com of the centre of Ganuza. The exposure Ganuza I prise, in ascending order AI, A2, B, C 1, C2 starts with a ca. 1 m thick, massive, hard lime (Ganuza); D, E1, E2, F (Ollogoyen). Microfacies stone/marl alternation (GA-I) some metres analyses were carried out i.a., by SCHWENTKE & below the track. The succeeding beds (GA-2) WIEDMANN (1985) and the reader is referred to may correspond to the ganuzai Event. LAMOLDA this paper. & al. (1989) referred to this exposure as the GA section and SANTAMARIA (1991, 1992) as Ganuza Unit AI: From the GZ beds, up to GI, is exposed a 16 I (GA). In my opinion, it ranges from the upper m thick marly succession with intercalations of thin Lower Turonian (ganuzai Event, ganuzailno limestone beds or limestone/marl alternations. Based dosoides Zone) up to the upper Romaniceras on foraminifera, the marls are referred to the Upper kallesi Zone of the Middle Turonian. Cenomanian - Rotalipora cushmani Zone (LAMOLDA & al. 1989). Ganuza II (GJ) Unit A2: The marls of unit Al are followed by a 4 m Location: Topographical map Metauten, sheet thick unit of closely-spaced limestone/marl alternations 140-13,1:10 000, R=570.820, H=4.727.560 with thin-bedded limestones. According to LAMOLDA & This section comprises the same stratigraphical al. (1989) these beds are the top part of the cushmani interval as the Ganuza I (GA) section and is situ Zone. ated about 100 m north of it. The beds continue This Upper Cenomanian alternation in terms of above the track in an another erosional gully. This foraminifera and referred to by LAMOLDA & al. (1989) section corresponds to the Ganuza II (GI) section as GI-1, is renamed herein GI in order to distinguish it of SANTAMARIA (1991, 1992) and LOPEZ (l990b, from the GI-1 beds of SANTAMARIA (1991) (and the use 1992d). in ammonite terms by LAMOLDA & ai. 1989), which are The Ganuza II (GI) section is very important upper Lower Turonian. The alternation GI crops out for regional correlations and comparison of pre some metres above the Ollobaren-Ganuza road. The viously published data of LOPEZ & SANTAMARIA lower 2.5 m of the unit corresponds in its appearance to (1992) and MARTINEZ & al. (1996) who used an the so-called flysch it boules (ORY & MENDIZABAL lower Turonian Choffaticeras quaasi Zone. The 1949). This, as in the Barranca, is developed as a suc basal beds of this section were incorrectly cession of dm thick calcareous marls and 0.1 m thick assigned to the basal Turonian (Choffaticeras limestones. According to SCHWENTKE & WIEDMANN quaasi Zone or quaasi Association; SANTAMARIA (1985, p. 13) some of the limestones are turbidites. 1992). Even taking other biostratigraphical data The upper 1.5 m of the unit are developed more uni from the literature into consideration, e.g. the formly and the beds compare in both thickness and reported local appearances of Spathites (1.) appearance with the topmost part of the Upper robustus (WIEDMANN) and Spathites subconcil- Cenomanian pictus Limestone of the Barranca 188 THOMAS KUCHLER (Iturmendi and Satrustegui sections, compare Text-fig. marls. The harder alternations weather in a nodular 6 and PI. 2). manner, and exhibit a yellow colour. In the upper part of the exposure sporadic inoceramids and ammonites Unit B: In the 30 m thick interval between 01 and OA- occur. 3 clay-rich marls are developed with intercalations of hard limestone beds (0.2 m) and about 1.0 m thick lime stone/marl alternations of the ?topmost Cenomanian - Ollogoyen Section (Middle Turonian to Upper Lower Turonian (Text-fig. 14A). Turonian, waltersdorfensis/germari Zone) According to LAMOLDA & al. (1989) the Cenomanian/Turonian boundary is placed at the bound Location: Topographical map Metauten, sheet ary between R. cushmani and Whiteinella baltica (=W 140-13,1:10 000, R=S69.7S0, H=4.726.S70 archaeocretacea) zones and lies ca. 2 m above the The exposed succession starts with Middle lithofacies boundary (see Text-fig. 14). Up to the Turonian strata (Romaniceras ornatissimum Mytiloides kossmati Event (OZ-3 to OZ-5 interval Zone), ca. 200 m west of Ollogoyen, south of a sensu SANTAMARIA 1991, or to 01-3 sensu LAMOLDA & field road. In the more northerly located erosion al. 1989) the succession is only very poorly exposed. al gully the lowest exposed bed is bed 01-102 This interval yielded no ammonites. On the other hand (sensu LAMOLDA & al. 1989) (PI. 4, Fig. 2) This LOPEZ (1992d, Text-fig. 31) cited many beds with bed corresponds to the top of the TU-VII (the inoceramids from this interval, corresponding to his zone with Romaniceras inenne) of LAMOLDA & Mytiloides submytiloides associations. About 10 m al. (1989, Text-fig. 11). In the erosional gully, above 01, within unit OZ-3 (see Text-fig. 14) lies the adjacent to the former and some metres to the base of the Mammites nodosoides Zone as defined by west, LAMOLDA & al. (1989) began the number SANTAMARIA (1991) and LAMOLDA & al. (1989). ing of the beds with 01-10 1, numbering only the Similarly SCHWENTKE & WIEDMANN (1985) report, limestones. However, ca. 10 m of marls occur probably from the same level, a rich fauna of below the base of their section. The church at ammonites and inoceramids. Unit B corresponds to Ollogoyen stands on the Middle Turonian lime zones TU-I to TU-II, sensu WIEDMANN (1979a, Text stones (unit C2). fig. 10) (see also Text-fig. 14B), though according to him, TU-I Zone is devoid of ammonites. Lithostratigraphy Unit Cl: In an erosional gully above the Oanuza - The Ollogoyen section exposes a ca. 100 m Ollobaren track up to 100 m thick dark grey clay-rich thick succession, extending up into the upper marls are exposed. In their lower part there occur many Upper Turonian Cremnoceramus waltersdorfen m-thick horizons with nodular calcareous marls, nodu sis/ Prionocyclus germari Zone (Text-fig. 15). lar limestones and accumulations of limestone nodules, the origin of which is closely associated with Unit D: The unit is represented by a monotonous, ca. Thalassinoides burrows. In the middle part of the unit 58 m thick, alternation of m thick dark-grey clay rich dm-thick limestone beds or m-thick, closely spaced marls and marls with beds of calcareous nodules or limestone/marl alternations predominate. The upper part continuous dm-thick limestone beds (0.15 to 0.3 m). of the unit is again more calcareous, with occurrence of m-thick parts with accumulations of calcareous nodules. UnitEI: This conspicuous unit, 1.5 m thick, is com Unit CI stratigraphically comprises an interval from the posed in part of distinctly bedded limestones ganuzail nodosoides Zone to the Romaniceras kallesi (Turonian-Coniacian boundary bed of LAMOLDA & al. Zone. This unit includes the upper part of unit Band 1981, Text-fig. II). Unit D is succeeded with sharp part of unit C of LAMOLDA & al. (1989). contact, by two 0.4 m thick limestone beds. Higher up follows a slightly arenitic limestone (0.06-0.09 m). The Unit C2: In the top part of the Oanuza I section occur topmost part of the unit is composed of a 0.5 m thick a ca. 5 m thick unit of thick-bedded limestones, which limestone bed with nodular appearance. still belongs in the R. kallesi Zone. The unit is much better accessible south of Ollogoyen, at the village Unit E2: Above the limestones of the preceding unit, a cemetery. It is composed there of m-thick intervals IS m thick succession of clay-rich marls is again devel with light grey marly limestones and calcareous marls, oped with sporadic intercalations of thin beds of cal with intervening marl seams and m thick, thin-bedded careous nodules or nodular limestones. ""I1 (lQ" ::; v. · MIDDLE TURONIAN UPPER TURONIAN if e ::; '0 '0 '0 Romaniceras deverianum Subprionocyclus neptuni Cr. waltersdorfensis/ P. germari '0 (1) (T) ::l S g Margotruncana fungicamerata Dicarinel/a primitiva o ~ ;:;; 0 g w ~ "'Cl ;:;; '"~ 0 $: ~ I I I I I I I I I I I I I I I I I I I o I "'I wI i 'I I I I I ~ I I I I I I I I I I I I I I I I I I I I I I I I p,: 0 l'j l'j Po...... , 1;1 .... N "J ~ g:. ( I 0 O~ 1 po (1) 00 1 1 I 1 1 :; :;1 :;; :01 ~ , 1::l 1 1 1 1 1 ~ I 0 I / 000 1 °0/ 0 0 o ~ < I I o 1 1 00 0 ( I ~ I 1 1 ( ij ( 1 ( I ( ...... 2. S2 1 ( I I 1 I ( I ~OO 1 I I I ( 1 1 1 ~ < < 0 I , I 1 00 ° 0 1 0 o < ( I I C 0- I 1 ~ ( I I 0 0 0 0' '0 (fQ 1 I 000 1 I 1 1 1 1 1 ( 1 0 o ( I 1 '0 0 1 I 1 ( 1 ~ ( ( 1 0°100/ 0 o 0 0 1 1 1 1 1 1 ~ I 1 ~ I I "-. '<(1) ( I OOi I 1 1 < 0 0 0 o ( ( >-l ::; I I I 1 1 ( 1 1°0°1°01 o 0 0 1 1 c I I I ~ 1 ( 1 ~ I I 'lj C if! ~~ I I I ( I I 1 1 1 ( ~ 1 ~ >-: (\l in J...~I I I I I 0 Ilv0 Ilo- 0o 0 0 0< ~ o 0 x ~ ::s r :0 C. :s :s :s » po 0 x x x ~ <' ::> ::> : ~ ~ x x x 0 n :9 cr (') :s " ~ w r; :;0 , i2 iil ~_ ::0- '"0- '" ~ 0 i I- 0- ~ ~ ~ W o 0 () '0 e; 0 p ~ ~ 00 '.0 pP ::; S; n~ I I I I I po " I tTl '1J ::> ~ I I I I --. Scaphites sp. indet ------_._------::; '{'3 .() o ----~-- Scaphites geinitzii C -, GIl ~ --- I I I I (jJ 9 ~ -: I I I I Romaniceras sp. JUV. o U po :>'i I I I I I ""I1 r:J ::> C:: I I I I n ~ n ~- Romaniceras deverianum >-l I I I I ::r: 3:: 5 is ----i------j------i------~------Romaniceras cf. deverianum ------tTl ;p. ::> rr. .- I ~ ;0 Hyphantoceras cf. ttl I I I I reussianum ? \0 ~ Ro I I I I 00 n·O Subprionocyclus sp. ~ tT1 - I I I I 9l !!; 5. ~ I I Subprionocyclus neptuni I ? z I I I I Z 5 ~ I I I I I 1-- Subprionocyclus gr. neptuni-hitchinensis n o ~ I I I I I ? (1) '!) ~t I I I I Subprionocyclus hitchinensis ~ 00 I I I I I .... - '!) I I Prionocyclus cf. germarz' E!. ~ I I I I I Po. I I 1 I i' Inoceramus sp. (gr. lamarcki-lusatiae) '" ::r~ I I I I I :3 ? I I I I I I I I 5," cr I Mytiloides ex gr. striatoconcentricus o -. I I I • a" 0 I I I I Cremnoceramus ex gr. waltersdorjensis o· ~ I I I I if! ::> I I I I Inoceramus lusatiae r=t 0.. I I I I ;';. (1) I I I qq" < I Inoceramus glatziae t "'0) ~gV 8 g ~~ ~§ ~ '0 ~ ~" ", ", ::r '" ..., ~ ~Iii .... ~ -~ "< '"i ~ ~ iii §"~ ~ ~. ~ ~. ()q '!) '" ,..• ~ ~ ; 00 ~ t :. '0 ~ ~! - - ::r '< 00 '!) (PZ661 '066Il ZCldOl pUB (Z661 '166Il VIIlVIWWVS JO 0110 pUB 10 0) spuods;l.l.TO::> UOI)::>;)S U;),(ojjoIlO ;)q) :(S[ '01 'L sjjI]-)Xgl '166Il VIIlVWVWVS pUB '(Z 'jjlJ-)Xgl '686Il'!IJ ?f? vmowvl '(Z 'jjlJ-)Xgl '686IllSNlltI?f? IlCl-rHJO)[ 19UB B)BP [BUOI)IPPB :S;»)IUOWWB JO g::>UBpunqB ;)A!lB[;Jl pUB SgjjIIBljB::>!)lgA 'S)UgAg q)!A\ 'UOI);)gS p.l1lpIIB)S U;),(ojjoIlO/BznuBD ;»)ISodwo;) ;)q) JO UUIU[O;) [B::>IqdBljjI)Bl)S-jB::>IjjO[Oq)q '91 'jj!d § '!.l iii i:f g' g> ~ III ~ O-~ "0: ~ => ~ " ;§ m~ ~ 0. < § »~ ~ 5" m ~ ~ ~ 0 0 3 ~. '" "a't ~ [ 8 III ~ m ~ ~ ~ ~=> '" ~;- ..,I"l ~ i & a: ~ l~ ~ 1:0 "a 1Li 0' to ~ l:l ~. ~ " ;l ~ I~ 'VVV'\~ 'VVV'\ "a & ~vv-.. '" -r- ~---+-- Lecointriceras fleuriasianum - Pachydesmoceras spp. I -1~'lj'-=i~;~'l~~lH ~i~~f~~::~~i=;; IIIi - - - - •••.••.•.• ...- N. (Eubostry.) sp. aff. matsumotoi -llf------[1--1 * -- ~ - fI - -I-r'l'! -- ::::~:::: ~:~!~:r:anus -.... ---Il ------+-H-- f--I.- --- .--- Spathites cf. reveliereanus ·f---II'i++---· +------Ij----- ,-- Fagesia cf. pachydiscoides ililr-iHI t--<;;t------tit······· I I IIfI- --[1~J~ i=lI if- l--- tIt... --- Fagesia.Fagesia aff.sp. rudra . .------ii-I--- -1------l------I --"1- •• -"'1'----'-1 -- ThomasJtes cf. rollandl T. sp. gr. gongilensis-koulabicus I~ ,~ of-----H%I-+-----+------Choffaticeras pavillieri -- Choffaticeras quaasi li! • [!j, -+---+101-+----+----- Kamerunoceras ganuzai ,--@---"---- Mammites nodosoides ...... _.. - Kamerunoceras turoniense .~ Romaniceras kal/esi ~-- -·--1---11-1 t;~--l~-~t·- Collignoniceras wool/gari ,--- Lecointriceras spp. -- Romaniceras omatissimum Scaphites geinitzii Hyphantoceras reussianum I~---mm;..... '. ..-- Romaniceras cf. deverianum •••'.... •• Romaniceras deverianum I; It------; -- Subprionocyclus sp. -' ••••••• ------i- :u:~r::;t:~~~;tc~~:::::s --- Subprionocyclus hitchinensis II - Prionocyclus cf. germari ~ ~ t '/I \l ~ Iil ~ filA"''''~ ~ ~\l~ !J.~~~ ~~ C"l =~ ••• ~ ~ 13 ~ 11 rJ filii ii fl, Ill?!" 111111 irllll.l~r iiii ,!IIi III =N il~I~~§ '" ~ !!l Il g: @ <3 @ 8 8 ~ ~ @ ~ ~'8 ~ ~ § ~ ~ ~ l'l ~ ~ ~ ~ ~ ~ ~ :8 '" ~ ~ :ll ij!= ~ ~ ~ !§;l :0 3$l o.:tI o .. 0 .3 .J " - • ~ 13 • 3 ~ i (JQ- '" ~ l~, 8. § * ~~ j ~ ~ ~~~ ~ I~g;e:t: ~ iE.:. 0 ~cg 2 is ~ ~ " 0 !::!. o· ~.~. l ~. ~ e- 5 ~.~ ~~ i'i;~~~~ i i-' :i:: ~. ~ ~ ; l ;+:t "iii ~ 3~ +~ ~ ~ ~ ll!.li'" t.? ·11 i ~ ~ UPPER TIJRONlAN upp« CEI! LOWER -+ MIDDLE TURONIAN = I .~; ~ _EY' ~ ~ i ~ C! ; g g Neoptychites spp ~~ ~ ~ ~ ~ ,.:.. :[ ,t Pseudoxybefoceras spp. ;~~.: g" ~ ; ~ ~~ ! l ~ '? ~ ~ ~ ~i iltIlH:)(l)[ SVWOHl 061 ACTA GEOLOGICA POLONICA , VOL. 48 T. KOCHLER, PL. 4 Middle- Upper Turonian succession of the Ollogoyen section (compare Text-figs 15-16) 1 - General view W -E; 2 - Close-up view of the lower part of section (Middle Turonian; Romaniceras omatissimum Zone); bed 01-102 cOlTesponds to the top of zone TU VII of WIEDMANN (in LAMOLDA & ai. 1981); 3 - Close-up view of the middle part of the section with beds 01-* 108b; 01-109 (Romaniceras deverian.um Zone) and beds 01-110 (Upper Turonian , Subprionocyclus neptuni Zone) , the latter vis ible in the middle part of the right side UPPER CRETACEOUS OF THE BARRANCA 191 Unit F: The 20 to 2S m thick unit is dominated by Text-figs 14, 16) are based on new bed by bed m-thick horizons of clay-rich limestones, beds with cal collections, supplemented by previously pub careous nodules and nodular limestones, alternating lished data based on KUCHLER & ERNST (1989) with clay-rich marls. and SANTAMARIA (1991, 1992). It proved extremely difficult to use the data Ammonite zonation in the Estella Aarea provided by WIEDMANN (l962b, 1965, 1979a), WIEDMANN & KAUFFMAN (1978) and LAMOLDA & Because of bad exposure conditions and, as aZ. (1981) and to recognize their zones in the mentioned already by LAMOLDA & aZ. (1989), the field. These papers contain faunal lists and thick rarity of macrofossils in the uppermost ness data for the various zones, but no detailed Cenomanian to lowermost Turonian part of the graphic sections or range charts. Moreover, the investigated Ganuza IV (GZ) section, a strati thickness data for individual zones are so dis graphical interpretation of this interval can be crepant, that some of the zones can be correlated made only on the basis of literature data. only approximately with the zonal scheme pre No reference is made here to some sections sented here. This problem particularly concerns located north of Ganuza which, according to zones TU-II through TU-VI, sensu WIEDMANN & LOPEZ (1990) and SANTAMARIA (J 991) should KAUFFMAN (1978), corresponding to zones expose the lowermost Turonian, and were TU-III through TU-VI in the formal scheme of unknown to me at the time of my own studies. WIEDMANN (1965). However, the interpretations of LAMOLDA & al. Reference to, and the correlation of the differ (1989), defining the base of the Lower Turonian ent zonal schemes presented by LAMOLDA & aZ. with the ammonite zone of W coZoradoense or (1989), KUCHLER & ERNST (1989) and that of SANTAMARIA (1991, 1992) with his Ch. SANTAMARIA (1991) was possible only through quaasi Zone at the base of the Ganuza II (GI) restudy of the sections and a re-evaluation of the section, respectively, contrast with the data pre published columns directly in the field. sented within this work. With the exception of the controversial top According to WIEDMANN'S ammonite scheme most Cenomanian to lowermost Turonian zones the uppermost Upper Cenomanian of northern (see discussion below) and an unnamed interval, Spain is divided into three zones (in ascending seven ammonite zones are distinguished in the order): Metoicoceras geslinianwn, Vascoceras studied sections. The positions of the zonal gamai and Fallotites subconciliatus zones (see boundaries as here defined are presented in Text SCHWENTKE & WIEDMANN 1985). The two latter fig. 17 against the schemes of WIEDMANN zones are endemic (KAPLAN & aZ. 1984, p. 329) (1979a) and LAMOLDA & aZ. (1981). and are regarded as an equivalent of the Neocardioceras juddii Zone by WIEDMANN & Metoicoceras geslinianum Zone aZ. (1989, Tab. 2). The stratigraphical succession of the intensive According to LAMOLDA & aZ. (1989), the upper ly studied Ganuza section, corresponding to l.5 m or l.0 m of the alternation GI comprises the Ganuza IV (GZ) of the Spanish authors, starts topmost part of the R. cushmani foraminiferal with Mytiloides frequency-maxima, particularly Zone and the lower part of the W archaeocre of M. kossmati, associated with Kamerunoceras tacea Zone. The record of M. geslinianum ganuzai (WIEDMANN). (D'ORBIGNY) places this interval within the ges According to LAMOLDA & aZ. (1989), this linianwl1 Zone according to SCHWENTKE & level corresponds to the level of first appearance WIEDMANN (1985, p. 13). of of M. nodosoides (SCHLUTER) and, conse quently, to the base or the lower part of the M. Vascoceras gamai or Neocardioceras juddii nodosoides Zone and thus to the upper Lower Zone Turonian. Eight ammonite associations have been recognized within the composite This and the overlying Turonian zone of W coZ Ganuza/Ollogoyen section, separated, in part, oradoense are controversial and in my opinion by several m-thick intervals with few not recognizable in the studied Ganuza section. ammonites. The range charts showing the local Despite a complete Cenomanian/Turonian stratigraphical distribution of ammonites (see boundary succession (see aZso SCHWENTKE & 192 THOMAS KUCHLER WIEDMANN 1985; LAMOLDA & PERYT 1995), specimen figured by SANTAMARIA (1991, PI. 4, according to WIEDMANN & KAUFFMAN (1978) the Fig. 1) as Kamerunoceras puebloense (COBBAN Vascoceras gamai Zone (equivalent of the N. & SCOTT) is also a K. ganuzai (compare PI. 9, juddii Zone), known from other sections in Figs 1-4,6). Consequently, I define the base of northern Spain, is not present here. the zone at the simultaneous entrance of both However, SANTAMARIA (1991) reported a sin index species. gle loose specimen of Neocardioceras sp. from a In the vicinity of Ganuza, a 10 to 15 m thick Cenomanian exposure (GA-IV), 1 km east of interval between the kossmati Event and the Ganuza. He correlated this so-called "association ganuzai Event is characterized by common small with Neocardioceras sp." with the north sized Kamerunoceras. The ammonite association European juddii Zone. additionally consists of spathitids, mainly S. reve liereanus, and, according to SANTAMARIA, of Watinoceras coloradoense Zone Fagesia aff. rudra (STOLICZKA) and Fagesia cf. pachydiscoides SPATH). Placenticeras aff. cum According to MARTINEZ (in LAMOLDA & al. minsi CRAGIN, Lecointriceras fleuriausianum 1989, p. 154, Text-fig. 2) the N. juddii and W (D'ORBIGNY) and Choffaticeras sp. first occur at coloradoense zones are indicated by the occur the level of the ganuzai Event. rence of Spathites subconciliatus (CHOFFAT) at A second association is known from the 10 m the top of GI -1 as well as by Spathites (1.) robus thick interval above the ganuzai Event, up to the tus (WIEDMANN) which occurs immediately lower part of the reveliereanus Event. The asso above. He postulated the presence of the Early ciation is characterized by rare choffati Turonian coloradoense Zone solely on the occur ceratids [Ch. quaasi (PERON), Ch. pavillieri rence of the latter species in the Ganuza II (GI) (PERVINQUIERE)] and representatives of the genus section. However, the base of the Turonian was Fagesia (F. pachydiscoides, F. thevestensis and incorrectly placed at Ganuza (see Text-fig. 14A F. aff. rudra) but is dominated by spathitids [s. and discussion above). Moreover, S. robustus is, reveliereanus, S. cf. reveliereanus, and rare S. at least in the Barranca, known to range up into obliquus (KARRENBERG)]. This interval may cor the middle part of the ganuzai! nodosoides Zone, respond to the Leoniceras discoidale Zone (TU i.e. into the upper Lower Turonian, where it co III) of WIEDMANN (1979b). occurs with Choffaticeras quaasi. Spathites reveliereanus dominates in the 14 m interval between GA-3 and GA-4 (= reveliere unnamed interval with rare ammonites anus Event) where it is associated with Nostoceras (Eubostrychoceras) aff. matsumotoi This is a 4 m thick interval below the kossmati COBBAN. The higher part of this interval is addi Event which according to SANTAMARIA (1991) tionally characterized by a heteromorph yields Spathites sp., Spathites (1.) reveliereanus, ammoniteamonite assemblage, compnslllg Thomasites ex gr. gongiliense - koulabicus and Metaptychoceras ganuzai WIEDMANN, Scipono Pachydesmoceras denisonianum (STOLICZKA). It ceras bohemicum (FRITSCH) and N. (E.) aff. mat probably ought to be referred to the upper Lower sumotoi. Rare M. nodosoides, M. cf. nodosoides Turonian K. ganuzailM. nodosoides Zone. as well as K. ganuzai also occur. The interval between the top of the reveliere Kamerunoceras ganuzailMammites nodosoides anus Event and the first K. turoniense yields Zone Sciponoceras bohemicum, Pachydesmoceras spp. (mostly P. denisonianum), M. nodosoides The base of the zone can be drawn only in the and S. cf. reveliereanus. The Schindewo(fites Ganuza IV (GZ) section. It approximately corre ganuzai Zone sensu WIEDMANN as well as the sponds to the GZ-3 horizon of SANTAMARIA Fagesia spp. Zone established by WIEDMANN & (1991, Tcxt-fig. 10) where, according to KAUFFMAN (1978) probably fall in this interval LAMOLDA & al. (1989), M. nodosoides first (Text-fig. 16). WIEDMANN (1960, 1965, 1979a) appears. It is also possible that the base of the reports a 15 m thick (later 18 m) interval with zone lies some metres deeper, as mentioned Fagesia from the Ganuza section. The accompa above. P. denisonianum and K. ganuzai (see PI. nying forms comprise Parapuzosia gaudama 9, Figs 1-4,6) were found in the basal part. The (FORBES), ieanrogericeras binicostatum UPPER CRETACEOUS OF THE BARRANCA 193 (PETRASCHECK) (=S. reveliereanus), Eubostry Zone sensu KUCHLER & ERNST (1989) (see Text choceras indicum (STOLICZKA) (=? N. (E.) aff. fig. 17). Near Ganuza in the basal part of the matsumotoi), and Metaptychoceras ganuzai. kallesi Zone there is a m-thick overlap interval of K. turoniense and R. kallesi. Kamerunoceras turoniense Zone Romaniceras ornatissimum Zone Field data gathered together with M. LAMOLDA, R. MARTINEZ and G. LOPEZ, S. SANTAMARIA, and The R. ornatissimum Zone as used here corre G. ERNST, reveal that the index taxon first appears sponds to WIEDMANN'S Romaniceras inerme in the Ganuza section ca. 14-17 m above the reve Zone (WIEDMANN 1979a, p. 175, Text-fig. 10; liereanus Event in the GA-6 horizon. It occurs WIEDMANN & KAUFFMAN 1978, p. III4). The base sporadically up to horizon GA-IO, and is some of the zone, defined by the FAD of the index what more common in GA-9 (see PI. 10, Fig. 1). taxon, lies in the Ganuza section within, or a The K. turoniense Zone probably more or less short distance above, the limestone unit at the top corresponds to the zone of Neoptychites spp. and of the exposed succession (compare LAMOLDA & Pseudoaspidoceras spp. sensu WIEDMANN &' al. 1989, Text-fig. 2), KAUFFMAN (1978). According to WIEDMANN In the Ollogoyen section, the ornatissimum (1965, 1979a) this zone was supposed to be chara Zone is ca. 10 m thick (WIEDMANN 1979a; cterized by Pseudoaspidoceras armatum LAMOLDA & al. 1981, p. 32, Text-fig. II) and was (PERVINQUIERE) and Pseudoaspidoceras salmu reported to contain R. ornatissimum [R. ornatissi riense (COURTILLER). KENNEDY & WRIGHT (1979) mum form C = R. inerme (DE GROSSOUVRE) sensu referred both species to K. turoniense WIEDMANN], R. kallesi [= Proromaniceras pseu (D'ORBIGNY). According to WIEDMANN (1979a, dodeverianum (JIMBO) sensu WIEDMANN] and p. 176) other associated forms include Kameruno Pachydesmoceras cf. linderi (DE GROSSOUVRE). ceras cf. inaequicostatus (WIEDMANN), S. cf. reve SANTAMARIA (1991 , Text-fig, 13) listed R. liereanus and Fagesia superstes (KOSSMAT). ornatissimum and Romaniceras sp. nov. (=Romaniceras navarrense SANTAMARIA 1995) Romaniceras kallesi Zone from the base of the zone, as well as Lecointriceras sp., R. kallesi and Scaphites cf. The zone is used here in the original sense of diana WRIGHT higher up-section, between 01-100 AMEDRO & BADILLET (1978) and of ROBASZYNSKI and 01-102, According to my own data, the & al. (1982), and not in the sense of SANTAMARIA ranges of R. ornatissimum and R. kallesi overlap (1991, 1992). Its lower boundary is defined by in the interval 01-102 to 01-104. Rare C. wooll the FAD of the index species, and in the Ganuza gari (MANTELL) (see PI. 10, Figs 6-7) and section it comprises a ca. 50 m thick interval with Lecointriceras sp. also occur in this interval. C. relatively few ammonites. woollgari was also listed by LAMOLDA & al. Based on a single loose find of R. kallesi by (1989, Text-fig. 2). SANTAMARIA (1992) later SANTAMARIA (1991, Text-fig. 7), and my own referred this specimen to Collignoniceras cf. collections in 1997, this species enters in the boreale (WARREN), The other finds of C. wooll nodular unit directly above the turonienselher gari, from the lower part of the section, reported cynicus Event (Ganuza I section, Text-figs 14 by LAMOLDA & al. (1989), were neither con and 16), and ranges up at least into the bedded firmed nor supplemented by SANTAMARIA (1991). limestones of unit C2. Consequently, the woollgari Zone of LAMOLDA & From my own in situ collected material ano al. (1989) is invalid. ther specimen of R. kallesi (see PI. 10, Fig. 8) is from a level ca. 20 m above the turonienselher Romaniceras deverianum Zone cynicus Event. The entry of Romaniceras ornatissimum (STOLICZKA) marks the upper The base of the zone, as well as its thickness, boundary of the zone. On the other hand, the are not as yet adequately understood in Navarra, broadly interpreted kallesi Zone of SANTAMARIA particularly in the Estella Area area and require embraces an interval corresponding in the pre further investigation. According to LAMOLDA & sented scheme to the kallesi, ornatissimum, dev al. (1981), the base of the zone lies about 50 m erianum zones and almost the whole neptuni below the prominent limestone bed OL-22 194 THOMAS KOCHLER (=01-110), i.e. at a level that most probably cor nensis, S. geinitzii, R. deverianum, juvenile responds to bed 01-104 sensu LAMOLDA & al. Romaniceras sp., and Hyphantoceras sp. (1989). According to LAM OLD A & al. (1981, p. Inoceramids are rare, and restricted to single 32), Romaniceras cf. deverianum (D'ORBIGNY), finds of Mytiloides ex gr. striatoconcentricus R. omatissimum, Collignoniceras sp., Puzosia from the Subprionocyclus I Event (Text-fig. 15). cf. planulata (SOWERBY) and P. denisonianum The neptuni Zone as defined here corresponds (STOLICZKA) occur within this zone. to the upper part of the kallesi Zone of The basal part of the zone contains only rare SANTAMARIA (1991,1992). ammonites, and consequently the position of the lower boundary of the zone as given by LAMOLDA Cremnoceramus waltersdorfensislPrionocyclus & al. (1981) could not be confirmed. SAN gennari Zone TAMARIA (1991, 1992) took the base of the zone significantly higher, at the top of the neptuni In the Ollogoyen section, KUCHLER & ERNST Zone, or even higher, in the lower part of the nor (1989) postulated an equivalent of the malis Zone (as defined by KOCHLER & ERNST Subprionocyclus normalis Zone, based on a sin 1989, Text-fig. 2). It must be emphasised that the gle specimen of Prionocyclus cf. germari specimens of R. deverianum, figured by (REUSS) and sporadic occurrences of KOCHLER & ERNST (1989) and by SANTAMARIA Cremnoceramus waltersdorfensis (ANDERT). (1991), actually come from high levels of the This zone was adopted and re-interpreted by Ollogoyen section. The specimen figured here GRAFE & WIEDMANN (1993) and GRAFE (1994) (Pl. 11, Fig. 6), however, comes from the for northern Spain. At Ollogoyen, the base of the Subprionocyclus I Event (01-* III b), directly zone was indirectly defined by the first appear above OL-110 (=01-22). An additional, small ance of C. waltersdorfensis, approximately 17 m specimen, referred to as R. cf. deverianum, was above bed 01-110 (KOCHLER & ERNST 1989). found 28 m down-section in bed 01-107a, and ca. Unfortunately, the inoceramid material (deter 20 m below the base of the neptuni Zone. From mined by E. SEIBERTZ) is represented by very these records it follows that the thickness of the poorly preserved specimens and consequently deverianum Zone in Ollogoyen, reported by the lower part of the zone remains uncertain. The WIEDMANN, is questionable. ammonite fauna in this zone is nearly identical Ammonites are again more common about 16 to that in the underlying neptuni Zone. It con m below the prominent 01-110 limestone bed. sists of Subprionocyclus neptuni, S. hitchinensis Here juvenile Romaniceras sp. and R. ?deveri (BILLINGHURST), s. gr. neptuni-hitchinensis, anum occur together with S. cf. geinitzii Romaniceras deverianum, R. cf. deverianul11 , D'ORBIGNY and Hyphantoceras reussianum Scaphites geinitzii and Hyphantoceras (D'ORBIGNY). reussianum, as well as juvenile specimens of Hyphantoceras. Prionocyclus cf. germari first Subprionocyclus neptuni Zone appears 3 m above the Subprionocyclus II Event, associated with R. deverianum. The latter In northern Spain, the zone was proved in the species (see PI. 11, Fig. 3) ranges considerably Ollogoyen section (KOCHLER & ERNST 1989) by a higher, up to bed 01-*8 (Text-fig. 16 not figured rich Subprionocyclus fauna. The base of the zone here). From a higher part of the section, his is now taken at the herein designated S. geinitzii Ollogoyen (01 II) section (not treated in this Bed (bed 01-109d), about 8 m below the level pre work), LOPEZ (1990b) reported an inoceramid viously taken as the boundary, at the top of 01-110. assemblage with rare Mytiloides incertus incO' The first Subprionocyclus neptuni (GEINITZ) (PI. tus (JIMBO), Mytiloides labiatoidifonnis 11, Fig. 8) associated with Scaphites geinitzii (PI. (TROGER), M. cf. labiatoidifonnis, and M. aff. 11, Fig. 7) occurs in this bed, together with poorly carpathicus (SIMIONESCU). The assemblage was preserved inoceramids, tentatively (TROGER, pO's. later referred by him to the upper Upper comm.) referred to the Inoceramus lamarcki or Turonian Inoceramus frechi Zone (compare Inoceramus lusatiae group. LOPEZ 1992d, Text-fig. 29). This appears to cor The zone is characterized by a Subpriono respond broadly to Zone 19 of TROGER (1989), cyclus - Scaphites - Romaniceras assemblage and, consequently to the normalis Zone sensu comprising S. neptuni, S. ex gr. neptuni - hitchi- KAPLAN (1986, 1988) thus supporting the origi- ACT A GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, Fig. 17 WIEDMANN 1960, 1965, 1979a KOCHlER, this work SANTAMARIA 1991,1992 LAMOLDA, LOPEZ & WIEDMANN & KAUFFMAN 1978 MARTINEZ 1989 KOCHLER & ERNST 1989 LAMOLDA et al. 1981 0:: z z w Z « « Subprionocyclus gr. 0. :;!; 0 Z Cr. waltersdorfensis/ 0. 0 0 P. germari nepluni-hilchinensis :::> :;!; 0:: :;!; Z :::> ..... SubprionocycJus 1 • 0.' • SubprionocycJus ...... Z Subprionocyclus II • . .... 0 I- Ev. Ev. 0 Ev. 0 0:: Romaniceras deverianurr 0 w ------? ------0- z Subprionocyclus neptuni 0- Subprionocyclus neptuni • SubprionocycJus 1 ---...... _- z :::> .... « .. I.. Subprionocyclus 1 ... ------? « • • geinitzii Bed ... , Z tfi Z 0 0- 0 Romaniceras deverianum 0:: Romaniceras deverianum a:: g; :::l ------:::> TU·VIII f- UJ ------? I- -l Romaniceras kallesi a:: 0 Romaniceras omatissimum W Romaniceras inerme UJ ....J TU-VII 0. 0 0 Collignoniceras wool/gari 0. 0 W :::l ~ Romaniceras kallesi ....J B ~ Neap/yehites spp. & 0 UJ -' Pseudaaspidoceras spp. 0 Q Kamerunoceras turoniense Kamerunoceras turoniense ~ Q ~ - ...... uronienselhercynicu.~ .. turonienselhercynicus ... TU·VI turonienselhercynicus ..... Fagesia Spp. TU·V GA-6 -\~~ Z • reveJiereanus Ev. z reveJjereanus Ev .•• ------? ------...... « . Schindewolfltes ganuzal « z Z Z « Mammites nodosoides Z « Mammites nodosoides Z 0 Z 0 0 Kamerunoceras ganuzai/ 0:: Leoniceras discoidale 0:: :::> 0 :::> 0:: Mammites nodosoides 0:: ~ :::> I- TU·III :::> t- I- • ganuzai Ev .• .tt. .... 0:: ganuzai Ev. I- ganuzs; Ev.····· ...... I UJ 0:: 0:: 0:: UJ Fal/otites subconciliatum '1' W • kossmati Ev. IL. s kossmati Ev. UJ kossmati Ev. S 0 'j" TU·II S 0 unnamed interval r------' ....J S ---:~:------....J TU-I 0 Watinoceras c%radoense 0 !__ Correlation of the ammonite schemes hitherto applied to the Ganuza/Ollogoyen standard section, by means of event stratigraphy; the zonations of WIEDMANN (1960, 1965, 1979a), WIEDMANN & KAUFFMAN (1978) and LAMOLDA & al. (1981), is only roughly completed due to the lack of precise, original presentation; the Choffaticeras quaasi Zone, sensu SANTAMARIA (1991, 1992), and the Watinoceras coloracloense Zone, sensu LAMOLDA & al (1989), represent the uppermost Lower Turonian ganllzailnodosoicles Zone UPPER CRETACEOUS OF THE BARRANCA 195 nal interpretation of KUCHLER & ERNST (1989). the Estella area), as well as the resulting differ The normalis Zone sensu KUCHLER & ERNST ences in bathymetry and temperature. (1989) is herein renamed the Cremnoceramus In the Estella area, the stratigraphical gap at the waltersdorfensisl Prionocyclus gennari Cenomanian - Turonian boundary has not been Assemblage Zone. Its base is defined tentatively recognized, and there are no black marls or black at the FAD of C. waltersdOljensis. clays. According to LAMOLDA & PERYT (1995), It is assumed that the Spanish waltersdorfen dysaerobic conditions in the topmost part of the sislgermari Zone corresponds entirely or in part cushmani Zone are recognizable by changes in to the Prionocyclus german' Zone of KAPLAN & the benthonic foraminiferal assemblages, dis KENNEDY (1994) in Germany, and embraces an played by a temporary disappearance of some interval referred to the deverianum Zone, as well taxa and their substitution by others. According as to the Subprionocyclus ex gr. neptuni-hitchi to those authors, such conditions persisted until nensis Zone or Association by SANTAMARIA the early Whiteinella archaeocretacea Zone. (1991, 1992). The base of latter author's S. ex gr. As indicated by the occurrence of the neptuni - hitchinensis Zone (bed T.13) lies Mytiloides I Event (=kossmati Event), the Lower below the Subprionocyclus II-Event of this paper Turonian is more complete in the Estella area (compare Text-fig. 17). Recent records of than in the Barranca. The ganuzai, reveliere Prionocyclus germari, M. incertus and anus, and turonienselhercynicus events are Mytiloides scupini in the Santander area (WIESE important for the correlation between both areas 1996, 1997) confirm the existence of the nor (Text-fig. 18). The timing of the tectonically malis (=gennari) Zone there, as previously pos induced Lower Upper Turonian Event (LUTE), tulated by KUCHLER & ERNST (1989). It should be documented in the Barranca by a shallowing noted in this context that WIESE (1997) erected a upward phase with associated marked lithologi M. incertuslP. germari Assemblage Zone which cal changes and hiati, has now been established was inferred to equate with the germari Zone of in Ollogoyen section. The LUTE is marked here northern Germany. by short-term, probably multi-phase redeposi tional events between the Scaphites geinitzii bed at the base of the neptuni Zone and the level of Event stratigraphy in the Estella area Subprionocyclus ex gr. neptuni-hitchinensis mass-occurrence in the Subprionocyclus I Event. The event stratigraphical scheme presented Strong subsidence of the basin was compensated here is the first proposed for the Ganuzal by a high sedimentation rate and consequently Ollogoyen standard section. It enables not only a there was no major difference in the bathymetric better correlation of particular sections near position. Ganuza but also reveals the discrepancies between the hitherto applied biostratigraphic Mytiloides I Event (=Mytiloides kossmati subdivisions (see Text-fig. 17). Event) The events consist of ammonite and/or inoce ramid accumulations that can be correlated with The horizon is a ca. 2.6 m thick succession those of the Barranca (see Text-figs 18-19). A developed between GZ-3 and GZ-5 in the continuity of particular horizons over a distance Ganuza IV section, comprising alternating thin of 34 km is demonstrable. Because of the more bedded (0.1 m) limestones and clayey, several complete and very much thicker successions of dm-thick marls. The topmost three beds are very the Estella area, compared to ·those of the rich in inoceramids, represented by Mytiloides Barranca (230 m against 56 m), the event hori labiatus, M. mJ. mytiloidesilabiatus, M. mJ. zons or event sets may extend over several labiatuslkossmati, M. kossmati, and M. cf. her metres, and consequently not so well defined and cynicus. Including additionally the data of LOPEZ easily recognizable as in the latter area. The (1990b) and also those of LAMOLDA & al. (1989), events also show considerable differences in the who reported an abundance of M. goppelnensis, faunal content and diversity, depending mainly a younger synonym of M. kossmati on the different palaeogeographical position of (W ALASZCZYK 1992, see afso HARRIES & af. the two areas (outer shelf in the case of the 1996) at this level, the assemblage is dominated Barranca, and middle shelf position in the case of by M. kossmati (HEINZ). In the Estella area, this (UOI;);).1 BIF')sg) SUOl)ISOd J[dljS -PIlLI 0) (lDUB.l.lU8) -.IdlOO Ul S)Ud.\d sn.J./U,C).I;)I/PSLld.lllO.fI1! pUB SillllJ;).I;)!I;)(\d.1 dlj) unplM Sd;3B[QU.l;)SSB PIlUB.l;);:'OUI/;))JUOU.lU.lV '8 I ';3ld LOWER :------~ TURONIAN Romaniceras kallesi t"J 1J'J "m >-l en~ "'en t"J t"" ~ao en Cl t"" "'",~a. § > er", C 5.g. N ~ ~ t"J 'III ~-g_. ~ N o o ",N o 00 ow 1!i " 0 o ~'" ~o - t ~ ~ ~ ~ Z 0' 00 '" '"0' :; ~Collignoniceras woollgari Romaniceras ornatissimum Romanineras kallesi cf. reveliereanus ·j\;jammites l1odosoides c ~\1~ S~~::;· ~~~ ~~i~*~- ~·~'2(~~~~' ,0&'8" '(\~\\\ •~~" i: ~.'"~~'"~~iR~~' ...~ ci ;:0: ,'\\\'i~~$~ ~.~ §. ~~~~B\ ~ j; ~~l." ..; ~'" ,~.~ ~ ::' ,,~- .-A ~~~~ ~;. ~ C/l ('> ~ '" \~~ ;:0: "0; \,~ ~~ ~. :0c. ~~~,i;, '!!i ~~\ '" ~ "'~l~,\,,,, t"J ~I ~ A 1J ~~'::~ c: ro II ~~~~ =.... '0'" '" ,\t~ !!i ~ ~ a. 0 ;;' o· OJ -g. '< Ul "'"a. '" --i a :0. ; OJ en'" (ii' o· n (M.) ex gr. labia/lis (M.) hercynicus '<'" (M.) cf. hercynicus [[]D r Kamerunoceras /uroniem c 0 I I '0 '. ':•••••• m ...*:,.:.\r[ammites c£ nodosoides '0 :e • ! ,Spathiles reveUereanus !!i !!i () () iii ~ 0;- () >'"1 en 00 ~ 0" "0 '"1 ~ c: '"c: ::::"en a. en V> ::T", §: 0" ~(f) N era."'''' c ~ a.. Z ,.,'"(f)~ ;. tl 0 r"'~ (fQ I , :e""(I) 0 --i ....; tv __ 0==:) ~ > en /~- -'--1 o 0 3. - ::l. ;;' '" -< '"2: t '-v-... r-~. '-D 00 ~ incipient hardground 0= nodular limestone bed, 00 = = limestOne nodules Hg hardground C;:;::;-::rv~ marl ~ sittic glauconitic limestone marly limestone ... glauconite limestone bed c::::::J lime marl fault limestone lag deposit ESTELLA AREA undifferentiated thlckbedded limestone eustatic and! or tectoeustatic event OLLOGOYEN nodular limestone T,J3 ~ 1..:f------32 km _____~. '\::: .§'-I:: ~ Subprionocyclus II Event 'z, 30 '"~ e:; ,~ -.-S! , BARRANCA ~ '" , .~ , ~ 25 IZURDIAGA I Z ~ .~ , i:: Q Forresteria 1-' :s ~ petrocoriensis Z (:> Micrasler corlesludillarium Acme~ U 0 ;s, :$ Z ~ ------20 20 0 ;;:;. 0 U ~ , Cremnoceramus .?. , rotundatus ~ , , , ...l~ 15 ,, 15 ~ 's;: Didymotis II Event~~ ~ ~ ~ ~ ;;:;.~ s:: Cremnoceramu 10 waltersdorfensi i 10 ] ? <.> G> c .s s:: Micraster ex gr. norm.-cort. Event ~ c ~ '\::: ~ §'" <.> SubpHonocyclus J3 'M neptuni :;:: ~1 Subpnonocyclus I Event l:l :;:: UE1$~2~~~ ~~~~~~~~==:'...~l ~ ~ -4 ....~ 5 -5 ~ -=- D ...1 1. E:: ~ ;:,: Rnmaniceras s:: 10 MTE ·10 ornaJissinnun ~ .~ DI=====* ------.--.... -.--.--~ .. ~ kallesil omalissimum Event ~ ~ ~ Romaniceras c ~ ~ I ...F'I.le.~ ..... ?_. ~ ~ '" 15 S ~ -15 Q '"<.> ~ '§ turonienselhercynicus Event ~ Kamenmoceras ~ E:: turoniense c ~ my/zloides Bed II ~ ·20 myliloides Bed I ~ TKil96/98 Fig, 19, Middle Turonian to Lower Coniacian event successions and correlation of the LUTE (lower Upper Turonian) Event between the Estella area and the Barranca 198 THOMAS KUCHLER lowest Mytiloides mass-occurrence falls in the mytiloides and M. cf. mytiloides (see also LOPEZ basal or at least lower part of the Kamerunoceras 1990, Text-fig. 11). LOPEZ also listed M. tran ganuzailMammites nodosoides Zone, as indicat siens (SEITZ) and commoner M. cf. transiens. ed by the FADs of the zonal indices in this event. The ammonite fauna is composed mainly of S. reveliereanus, juvenile forms of Spathites and Kamerunoceras ganuzai Event Mammites, and N. (Eubostrychoceras) aff. mat sumotoi. Spathites obliquus (KARRENBERG), This event is located stratigraphically in the Spathites robustus, and Spathites subconciliatus basal part of the 2.2 m thick interval between occur rarely (LAMOLDA & al. 1989). Fagesiids GZ-6 and GZ-7, as distinguished by SANTAMARIA are common, while sciponoceratids and choffat (1991, Text-fig. 10). In contrast to the Barranca, iceratids are rare. the horizon here yields a more diverse ammonite fauna. The lower 0.5 m, composed of alternating Kamerunoceras turoniensel Mytiloides 0.1 m thick marls and marly limestones, are par hercynicus Event ticularly fossiliferous. The second limestone bed includes a level with In the Ganuza I section (Text-fig. 18) this sporadic inoceramids, comprising M. cf. labiatus, stratigraphic event extends over 13 m from bed M. ex gr. labiatus, M. mytiloides, M. cf. hercyni GA-9 to bed GA-lO. The basal 0.3 m thick, shell cus, and M. mJ. labiatuslkossmati. The detrital limestone bed (GA-9), with Mytiloides ammonites are dominated (up to 50% of the hercynicus and M. cf. hercynicus, is followed by assemblage) by Kamerunoceras ganuzai. The a ca. 7.0 m thick clayey marl (GA-9b) with two assemblage also includes Spathites reveliereanus inoceramid horizons yielding M. hercynicus and (19%), Lecointriceras fleuriausianum (6%), M. cf. hercynicus. The overlying unit consists of Fagesia sp. (13%), Choffaticeras sp. (6%), and ca. 2 m thick horizons of nodular limy marls or Placenticeras aff. cUinminsi (6%). The latter nodular limestone beds (bed 29 and 30) with a 1.6 three genera indicate a stronger Tethyan or warm m thick marly bed in between. These beds, as water faunal influence in the Estella area. About well as the two overlying ones, also yield inoce 1.5 m above the alternation a marly limestone bed ramids. LOPEZ (1990, Text-fig. 11) also listed M. yields a second frequency-maximum of K. cf. hercynicus also from the topmost part of this ganuzai associated with P. aff. cumminsi. A sim event-bundle and for several metres above. M. ilar ammonite association, comprising K. ganuzai labiatus, dominant within the turoniense!her (= Kamerunoceras puebloensis COBBAN sensu cynicus Event in the Barranca is missing here. SANTAMARIA), Fagesia pachydiscoides, Fagesia Ammonites are very rare and of extremely low sp., Pachydesmoceras linderi (DE GROSSOUVRE), diversity. K. turoniense occurs sporadically, Lecointriceras fleuriausianum, and Choffati namely the compressed ribbed type salmuriense, ceras pavillieri, was also reported by but it is practically restricted to this interval. P. SANTAMARIA (1991, 1992) in these beds. denisonianum is similarly rare. Spathites reveliereanus Event Romaniceras kallesilR. ornatissimum Event In the Ganuza I (GA) and Ganuza II (GI) sec This event lies in the ornatissimum Zone and is tions, the reveliereanus Event spans an interval represented by an acme of romaniceratids above several metres thick. The succession is composed the m-thick limestone unit C2. In the basal part of of nodular calcareous marls or layers of calcare the Ollogoyen section R. kallesi dominates also ous nodules (GI-l to GI-2, and GA-3 to GA-4 over R. ornatissimul11 while the associated fauna respectively), separated by a some m-thick marly is composed of Collignoniceras woollgari, horizon (see Text-figs 14, 18). In contrast to the Lecointriceras boreale, Lecointriceras sp. and cquivalent level in the Barranca (Text-fig. 11), Scaphites geinitzii. medium-sized spathitids are common, while the rather sparse inoceramids are more diverse. The Scaphites geinitzii Bed latter are represented by Mytiloides mytiloides, M. cf. mytiloides, M. ex gr. labiatus, and M. mJ. In the Ollogoyen section (Text-figs 15,19) this labiatuslkossmati, with a dominance of M. very thin horizon, represented by a hard clayey UPPER CRETACEOUS OF THE BARRANCA 199 marl, coincides with the FAD of Subprionocy Stage Boundaries in Brussels 95, the base of the elus neptuni, and is characterized by common S. Turonian should be drawn at the FAD of the geinitzii. It most probably lies at the base of the ammonite species Watinoceras devonense S. neptuni Zone, or at least in the basal part of WRIGHT & KENNEDY (see BENGTSON 1996). At this zone, and consequently in the basal part of Ganuza, LAMOLDA & PERYT (1995) defined the the Upper Turonian. base of the Turonian in terms of nannoplankton with the appearance of Quadntl11 gartneri PRINS, Subprionocyelus I Event a level falling within the Whiteinella archaeoc retacea foraminiferal zone. However, the base of This event is marked by a frequency maximum the Turonian could not be recognized by means of Subprionocyelus spp., namely S. neptuni and S. of ammonites. ex gr. neptuni-hitchinensis but mainly specifical WIEDMANN'S zones introduced for the Lower ly indeterminate specimens. In the Ollogoyen sec Turonian of the Estella area (see WIEDMANN tion (Text-fig. 15) it lies within a ca. 1.0 m thick 1979a, Text-fig. 10), are largely unusable. This is interval (OI-*I11b), directly above bed 01-110 also the case with the Choffaticeras quaasi Zone (after LAMOLDA & al. 1989) or 01-22 (after introduced by SANTAMARIA (1991,1992) for the LAMOLDA & PROTO-DECIMA 1986). Ammonites basal Turonian, and with the Watinoceras col are concentrated at three levels; in the topmost oradoense Zone of LAMOLDA & al. (1989). 0.03-0.05 m of 01-110, as well as 0.3 m and ca. 1.0 In the Estella area, Kamerunoceras ganuzai m higher. S. neptuni and S. ex gr. neptuni-hitchi and Mammites nodosoides appear more or less nensis co-occur with rare R. deverianum, simultaneously, at a much lower stratigraphical Scaphites sp. and Hyphantoceras cf. reussianum. level than assumed by WIEDMANN, and already in The rare inoceramids are usually poorly preserved his Fallotites subconciliatus Zone. An associa and therefore indeterminable, apart two specimens tion with Choffaticeras spp. first occurs in the referred to Mytiloides ex gr. striatoconcentricus. middle part of the ganuzailnodosoides Zone. This part corresponds to WIEDMANN'S Para Subprionocyelus II Event mammites? saenzilLeoniceras discoidale (or Leoniceras discoidale) Zone. Only above its The second Subprionocyelus acme-horizon, appearance levels and in the middle part of the where the genus comprises up to 70% of the ganuzai/nodosoides Zone as introduced here, an ammonite assemblage, is located stratigraphically association with Choffaticeras spp., correspond within the normalis Zone (sensu KUCHLER & ERNST ing to WIEDMANN'S Paramammites? saenzilLeo 1989), or the Prionocyelus waltersdOljensis/ger niceras discoidale Zone (or Leoniceras dis mari Zone as used here (Text-fig. 15). It lies about coidale Zone) can be observed. In the Ganuza 31 m above limestone bed 01-110 and about 3 m sections, WIEDMANN'S zones from TU-II through below bed T. 13 of SANTAMARIA (1991). TU-IV lie within the range of K. ganuzai and fide The ammonite association, beside Subpriono LAMOLDA & al. (1989) also in the range of M. cyelus ex gr. neptuni-hitchinensis and S. hitchinen nodosoides (see Text-fig. 16). Similarly, the Ch. sis comprises Romaniceras cf. deverianum, H. cf. quaasi Zone, or better, quaasi Assemblage of reussianum, S. geinitzii, and S. cf. geinitzii. Bed SANTAMARIA (1991) is incorrectly stratigraphi T. 13 corresponds to the level of the stratigraphical cally placed below the M. nodosoides Zone in ly lowest occurrence of Prionocyelus cf. germari. Ganuza. In my opinion, this is the result of an In and above T. 13, SANTAMARIA (1991) still found incorrect interpretation of the Ganuza II (GI) sec representatives of the neptuni - hitchinensis group. tion, which is located not below, but above, the GZ section, and consequently lies already above the FAD of M. nodosoides (see SANTAMARIA SUMMARY AND DISCUSSION OF THE 1991, Text-fig. 10). BIOSTRATIGRAPHICAL RES UL TS The only specimen of Ch. quaasi (PERON) in the 01 section (Text-fig. 14) therefore comes Lower Turonian from the middle part of the ganuzailnodosoides Zone, well above the ganuzai Event. This corre According to the proposal of the Second sponds to its first occurrence in the Barranca. The International Symposium on the Cretaceous ganuzailnodosoides Zone is treated here as the 200 THOMAS KOCHLER Spanish equivalent of the European nodosoides the French turoniense Zone (sensu AMEDRO & Zone, which at Ganuza, at least, comprises the BADILLET 1982) comprises both the upper Lower upper part of the F. subconciliatus Zone, as well Turonian and the basal Middle Turonian, rather as WIEDMANN'S L. discoidaZe and Schinde than (as previously postulated) only the lower part wolfites ganuzai zones. The widespread and rel of the woollgari Zone. It is clear that K. tur atively common K. ganuzai represents a much oniense, as already suggested by KENNEDY & better index species than M. nodosoides in north WRIGHT (1979), COBBAN (1983) and ROBASZYNSKI ern Spain. The latter, at least within the lower & aZ. (1990), appear as low as Lower Turonian M. part of its range, is relatively rare in Navarra. nodosoides Zone in the southern faunal province. In northern Spain the base of the K. turoniense Zone, defined by the FAD of the zonal index, thus Middle Turonian falls within the M. nodosoides Zone of the north ern European scheme. The FAD of the ammonite species Contrary to the view of SANTAMARIA (1991, Collignoniceras woollgari (MANTELL) was pro 1992), it is possible to distinguish Romaniceras posed (BENGTSON 1996) as the base of the kallesi, R. ornatissimum and R. deverianum Middle Turonian. This definition is, however, zones, above the K. turoniense Zone in the not suitable for northern Spain, where Middle Turonian of the composite Ganuza/Ollo MANTELL'S species is rare. Moreover, C. wooll goyen succession. gari appears diachronously in different regions. Thus according to the data in this paper, it appears no lower than the Romaniceras ornatis Upper Turonian simum Zone in the Estella area, while in France it is reported already from the upper part of the During the Second International Symposium on turoniense Zone. Cretaceous Stage Boundaries in Brussels, 95, no This is the reason why WIEDMANN (I 979b, formal proposal was made regarding the base of Table 2) recognized an equivalent of the vvooll the Upper Turonian. Apart from criteria based on gari Zone in northern Spain, i.e. his ammonites, namely the FAD of R. deverianum or Collignoniceras sp. Zone, only above the K. tur S. neptuni, an alternative proposal was to place the oniense Zone (=Zone with Neoptychites boundary at the FAD of the inoceramid species cephaZotus). The Collignoniceras sp. Zone of Inoceramus costellatus WOODS (see BENGTSON WIEDMANN corresponds, in the scheme presented 1996). The FAD of 1. costellatus lies close to that here, to the R. kallesi and R. ornatissimum zones. of S. neptuni. In Westphalia, the base of the Upper Records of C. woollgari lower in the Turonian Turonian is taken at the costellatuslpZana Event can be attributed to incorrect determinations. (sensu ERNST & aZ. 1983) which marks the FAD of Consequently, C. woollgari does not match the 1. costellatus (see KAPLAN 1986). KAPLAN & requirements for a boundary marker of the KENNEDY (1994) showed that the FAD of S. nep Middle Turonian in northern Spain. tuni lay 4 m above the costellatuslpZana Event. The base of the Middle Turonian is defined here The two FADs are thus situated very close to one with the FAD of K. turoniense. In the condensed another, so that the new boundary criterion close sections of the Barranca, this species first appears ly approximates to the most widely used boundary within the S. reveZiereanus Event, co-occurring criterion in the sense of HANCOCK & aZ. (1977), with M. cf. nodosoides and with S. reveZiereanus. i.e. at the base of the S. neptuni Zone. In the more complete and more expanded succes In Spain (WIEDMANN 1960, 1965, 1979b; sions of the Estella area, it seems to appear high KOCHLER & ERNST 1989) and in France (e.g. er, where it is common for the first time within the AMEDRO & aZ. 1982) this boundary was com turonienselhercynicus Event. monly (in the traditional sense of DE GROSSOUVRE With reference to the situation in France and 1889) placed at the FAD of of R. deverianum northern Germany, C. ;voollgari has its FAD at the (D'ORBIGNY). According to KENNEDY & aZ. level of the hercynicus Event (ERNST & aZ. 1983), (1986) R. deverianum co-occurs with C. wooll corresponding to the turonienselhercynicus Event gari in the Paris Basin, while according to recognized here. Its FAD thus falls within the AMEDRO & aZ. (1982) in France it ranges up only upper part of the turoniense Zone. Consequently, to the FAD of S. neptuni. UPPER CRETACEOUS OF THE BARRANCA 201 In northern Spain, R. deverianum appears con interval corresponds entirely to the German siderably lower than the FAD of S. neptuni (fide Prionocyclus gennari Zone of KAPLAN & WIEDMANN in LAMOLDA & al. 1981) and ranges, KENNEDY (1994). in the Estella area, up to the topmost Upper In Germany, on the other hand, C. waltersdor Turonian, where it is recorded in association with fel1sis was first recorded by some authors (WOOD S. neptuni in the neptuni Zone, and with & al. 1984; KAPLAN 1986, 1988; KAPLAN & Prionocyclus cf. germari in the nonnalis Zone KENNEDY 1994, KAUFFMAN & al. 1996) in the (i.e. waltersdOljensis/germari) Zone (KUCHLER uppermost part of the P. germari Zone, in an & ERNST 1989). interval referred to as the C. waltersdorfensis In the Santander area, R. deverianum occurs Zone. This zone lies immediately beneath the likewise in a stratigraphically narrow interval Turonian/Coniacian boundary and ranges from below the FAD of S. neptuni, where it overlaps the DidYl110tis II Event to the FAD of with S. neptuni, up to a high level in the neptuni Cremnoceramus rotundatus (TRouEK non FIEGE) Zone (see WIESE & KUCHLER 1995, WIESE 1997). in the German Salzgitter-Salder section (see Furthermore in the Ollogoyen section R. deveri KAUFFMAN & al. 1996). anum was actually found mainly in the neptuni However, KELLER (1982, p. 38; Text-fig. 17) Zone (see KUCHLER & ERNST 1989, SANTAMARIA reported one of the lowest German records of C. 1992, and this paper). All these reports complete waltersdorfensis from the base of his ly refute HANCOCK's (1991) statement that Subprionocyclus aff. norma lis Zone in the Sack "nobody has ever found R. deverianwn in the S. Syncline (Sack I section). There, fide KELLER neptuni Zone of the Turonian as used here" as (1982), the species occurred rarely, in association well as show the renewed ignoring of data by with S. aff. nonnalis, between a tuff-layer and an some members of the Subcommission, who abundance-maximum of Micraster ex gr. assume that (in BENGTSON 1996) "The main leskeilcortestudinarium. This Micraster acme is problem lies, however, in the fact that the relative interpreted herein as an equivalent of the position of the FOs of the two species are uncer Micraster Event sensu ERNST & al. (197883). tain, as they rarely co-occur". Contrary to the for TROGER (1989, Text-fig. 2) also reported C. wal mer view (see KUCHLER & ERNST 1989) and in an tersdorfensis together with M. incertus and M. approach towards the proposal of the Brussels labiatoidiformis in Zone 19, which equates with Symposium, the base of the Upper Turonian is the M. labiatoidifonnis Zone sensu WOOD & al. placed here at the FAD of S. neptuni (see also (1984), i.e. above the Hyphantoceras Event and WIESE & KUCHLER 1995), the definition which below the base of the nonnaZis Zone (sensu had already been used by LAMOLDA & al. (1989). KAPLAN 1988). The base of the nonnaZis Zone, In the Ollogoyen section there is an internl, lying below the Micraster Event, corresponds below the FAD of S. neptuni, in which R. deveri more or less to the base of the Inoceramus aff. anum co-occurs with H. cf. reussianum and frechi Zone, now renamed the Mytiloides scupi S. geinitzii, allowing a R. deverianum Zone to be ni Zone (see W ALASZCZYK & TROGER 1996). On distinguished in the topmost Middle Turonian. the other hand, the base of the germari Zone The Upper Turonian of northern Spain may be (which replaces the nonnaZis Zone) is defined by divided into two ammonite zones, namely, the S. the FAD of Prionocyclus gennari, 3 m above the neptuni and Prionocyclus germari zones. In the Micraster Event (KAPLAN & KENNEDY 1994). Estella area, the neptuni Zone, as here defined, Recently, HORNA & WIESE (1997) reported C. comprises the upper part of the kallesi Zone of waltersdorfensis in the lowermost part of the SANTAMARIA (1991, 1992). In addition the top "GrauweiBe Wechselfolge" in the Hoppenstedt most Turonian can also be treated as a section. There, the species occurs within the scu Cremnoceramus ,valtersdorfensislPrionocyclus pini Zone at a level correlatable to the lower part germari Assemblage Zone. of the germari Zone (WIEsE,pers. comm. 1998). The Spanish waltcrsdorfcnsis/germari Taking these data from Germany into considera Assemblage Zone is defined at the FAD of tion, the FAD of C. waltersdOljensis seems to be in the inoceramid species C. waltersdorfen a similar stratigraphical position in northern Spain. sis (ANDERT) which in the Barranca appears In the Barranca, C. waltersdOljensis first appears around the MiCl"aster ex gr. l1ormanniae-cortes around an abundance peak of advanced Micraster tudinarium Event. It is assumed that the Spanish of the l1onnanniae-cortestudinariul11 group, i.e. a 202 THOMAS KUCHLER time-equivalent of the German Micraster Event. In nous. However, the composItIOn of the inoce the Estella area, the latter is not developed, but C. ramid populations at species level in this event waltersdOJjensis occurs between an equivalent of differ markedly, probably for ecological reasons. the German Hyphantoceras Event and the FAD of Thus, in Germany (see DAHMER & al. 1986) and Prionocyclus cf. germari. similarly also in Colorado, Western Interior, it is In northern Spain, furthermore, the waltersdor dominated by Mytiloides mytiloides. In the stud fensis/germari Zone embraces an interval referred ied Spanish sections the dominant form is M. to as the Romaniceras deverianum Zone as well as kossmati. At Pueblo/Colorado, according to to the Subprionocyclus ex gr. neptuni-hitchinensis KENNEDY & COBBAN (1991) (see also BENGTSON Zone of SANTAMARIA (1991, 1992). Despite the 1996) the first Mytiloides abundance peak (the fact, that Mytiloides scupini was not found during Mytiloides Event of BIRKELUND & al. 1984) IS this investigation, the zone may also correspond to recorded from within the nodosoides Zone. the Mytiloides scupini!Prionocyclus gennari Assemblage Zone of WIESE (1997). Kamerunoceras ganuzai Event EVENTS; REGIONAL AND INTER-REGIONAL It is defined as an abundance-maximum of K. CORRELATION ganuzai, associated with another Mytiloides acme, in the middle part of the upper Lower Mytiloides kossmati Event Turonian ganuzai/nodosoides Zone. It is so far known only from Navarra, where it provides the Because of the dominance of Mytiloides koss first isochronous horizon between the Barranca mati (HEINZ), the lowest Mytiloides Event recog and the Estella area. In the Santander area, the nized in the Estella area is called the M. kossmati stratigraphical interval with the inferred position Event. Based o.n its stratigraphical position, it can of the ganuzai Event falls in a hiatus that extends be correlated with the Mytiloides Event sensu up into the Kamerunoceras turoniense Zone (see stricto of authors. This event is interpreted as the WIESE 1997). first evolutionary burst of the genus Mytiloides above the Cenomanian/Turonian boundary (the first Mytiloides, e.g. Mytiloides hattini ELDER, Spathites reveliereanus Event occur already in the topmost Cenomanian). According to HARRIES & KAUFFMAN (1992) the As in the case of the ganuzai Event, the reve Mytiloides Event is associated with the peak - liereanus Event, represented by an acme-occur highstand facies, at a time of maximum flooding. rence of spathitids (including the index species, It is assumed that this burst was additionally S. reveliereanus) has so far been recognized only favoured by the ending of the Oceanic Anoxic in the Barranca and the Estella area (Text-fig. Event II (KAUFFMAN 1986) and/or the ending of 18). It is situated at the base of the K. turoniense the synsedimentary tectonics (ERNST & al. 1992, Zone. However, similar acme-occurrences of DAHMER & al. 1986, HILBRECHT & DAHMER Spathites are also known from France (see 198694) connected with the Cenomanian AMEDRO & HANCOCK 1985, Text-fig. 2) (see Turonian Boundary Event (CTBE). Text-fig. 20) but their event character and strati This Mytiloides-acme possesses a nearly graphical position require further study. The world-wide record, and is noted at the boundary combination of the reveliereanus Event with yet between Watinoceras coloradoense and another Mytiloides-acme suggest that it might be Manllnites nodosoides zones, or in the basal part an equivalent of the so-called 3rd Mytiloides of the latter zone, from Germany (ERNST & al. Event in northern Germany. 1983, KAPLAN 1986), England (HANCOCK 1989, p. 574), as well as from thc Western Interior (KAUFFMAN 1986, KENNEDY & COBBAN 1991). Middle Turonian Event (MTE) From northern Spain, it was already indirectly reported by WIEDMANN & KAUFFMAN (1978), This event was probably induced by regional LAMOLDA & al. (1989) and LOPEZ (1990). This tectonism in the Middle Turonian. In the Arardi Mytiloides-acme thus seems to be nearly isochro- and Izurdiaga sections of the Barranca, it is UPPER CRETACEOUS OF THE BARRANCA 203 expressed by the kallesi/ornatissimum Event, a the preservation of the fauna indicate, as in the bed of hiatus concretions and reworked Barranca, low sedimentation rates and rework ammonites within a hardground series in the ing. WIESE & WILlvlSEN (in press) interpret the Middle Turonian ornatissimum Zone. The exact kallesi Event as a fossil accumulation during a horizon of the kallesi/ornatissimum Event has sea-level highstand. In this context, it can be not so far been established in the more expanded explained as generated by a low sedimentation Ganuza/Ollogoyen section. rate and/or condensation (WIESE 1995). In northern Spain the event seems to be slight ly diachronous. Near Santander, it is apparently earlier and documented by the so-called kallesi Kamerunoceras turoniense/Mytiloides Event (sensu WIESE 1995), which falls into the hercynicus Event upper part of the kallesi Zone. WIESE (1995) described a m-thick succession of glauconitic This event lies in the upper part of the K. limestones and glauconite marls in proximally turoniense Zone. In northern Spain it is located sections, the topmost bed of which forms expressed by a mass-occurrence of ammonites, a Thalassinoides hardground. particularly of Sciponoceras bohemicUln, The kallesi Event represents a mass-occurrence Kamerunoceras spp. and Spathites spp. This of the index taxon, as well as of large characteristic and often high diversity assem Pachydesmoceras cf. denisonianum, Puzosia blage is well documented in condensed, outer sp., Neoptychites cephalotus and Spathites reve shelf sections, situated in marginal parts of sub liereanus. The sedimentary characteristics and marine swell (Text-fig. 18). The associated 'fa France Northern Spain .9 '0 (Saumurois) (Navarra) ~ s:: ,21 8 @ turonienselhercynicus .t.... (1) reveliereanus Event ....: I peak occurrence last occurrenc·e J. first occurrence TKu98 Fig. 20. The position of the rel'eiiereal1us and turol1iel1selhercYl1iclis events within the local ranges of Kamenll10ceras turOl1iellSe in northern Spain and in France and calibration of the local FADs of Col/ignol1iceras wool/gari and the local LADs of Mammites l1odosoides in northern Spain. France, and north-western Germany by using these events as more or less isochronous marker horizons: as C. wool/gari enters the interval around the hcrc)'nicus Event in north-western Germany, and in the same position (turol1iel1selhercynicus Event) in France, this level is of importance for an intcr-basinal correlation and can aid, as an isochronous marker, for calibration of different biostratigraphic frameworks. In northern Spain, C. wool/gari appears delayed in the Romal1iceras ornatissimum Zone, this mcans one ammonite zone later. The base of the Middle Turonian, defined at the FAD of C. wooilgari (BENGTSON 1996), would approximate the position of the Spanish tUrDniel1selhercynicus Event 204 THOMAS KOCHLER inoceramids are dominated by Mytiloides labia level were recorded about 124 ammonite speci tus (SCHLOTHEIM). Towards more proximal sec mens referred to Lewesiceras peramplul11 (46% tions with thick sedimentary successions, due to of the collection), S. reveliereanus (25%) and K. high accumulation rates (e.g. Estella Basin) and turoniense (15.3%), with subordinate Neopty more basinward, bathymetric ally deeper posi chites cephalotus, Spathites combesi and tions (e.g. Satrustegui), the ammonite frequency Lecointriceras costatum. The species C. wooll markedly decreases. In the latter case, the gari, which has its FAD at this level, belongs, decrease is probably attributable to a reduction in according to KENNEDY & aZ. (1982) to the sub the preservation potential of the ammonites. In species C. woollgari lvoollgari sensu COBBAN & the same directions, the ratio between M. labia HOOK (1980), an early form characteristic of the tus and M. hercynicus also changes with an basal C. vvoollgari Zone. Thus, the base of the increasing dominance of the latter species. woollgari Zone and, consequently, the base of the The turonienselhercynicus Event is, moreover, Middle Turonian, lies in the upper part of the the highest level of common occurrence of M. French Kamerunoceras turoniense Zone. The hercynicus or similar forms. Above this event, associated inoceramid fauna (from Saumur) is there are only sporadic occurrences of forms dominated by M. mytiZoides and M. Zabiatus, referable to M. cf. hercynicus. with subordinate M. hercynicus, which is very According to ERNST & KOCHLER (1992), the characteristic of this interval (see ROBASZYNSKI turoniense!hercynicus Event of northern Spain & aZ. 1982, Text-fig. 5). corresponds to the hercynicus or subhercynicus The other French section in which a tur Event, sensu ERNST & al. (J 983) of northern onienselhercynicus Event can be inferred is the Germany. The latter event lies in the basal part of 57 motorway cutting near Taillebourg, described the apicalislcuvieri Zone and, in basinal sec by AMEDRO & HANCOCK (1985, Text-fig. 2) and tions, is recorded by an acme of the index inoce interpreted by them as extending from the ramid. The hercynicus Event is recorded from Mammites nodosoides to the R. kallesi Zone. In several sections in both Lower Saxony and my opinion, both the reveliereanus Event and the Westphalia. In Westphalia, KAPLAN (1986) turonienselhercynicus Event were exposed in reported the lowest Collignoniceras woollgari this section which, therefore, spanned only the from this level. This species is widely distributed turoniense and kallesi zones. The ca. 2 m thick but of rare occurrence in this area. However, in interval of the turoniense Zone, sensu AMEDRO & the marginal deposits of the Ham'strang, C. HANCOCK (1985) is here interpreted as the tur woollgari is common, associated with onienselhercynicus Event, recorded by a marked Sciponoceras bohemicum, Neocrioceras multi acme of Spathites reveliereanus, associated with nodosum, Lewesiceras peramplum (MANTELL), C. woollgari, rare K. turoniense and Neopty and Collignoniceras carolinum (D'ORBIGNY). chites cephaZotus. On the other hand, the 1.0 m In my opinion, this event is also recognizable thick interval the 5 m and 6 m marks in their sec in France, where it likewise corresponds to the tion, which yields an abundance-maximum of S. FAD of C. woollgari, whereas in northern Spain reveliereanus, associated with rare M. C. woollgari appears well above this level, nodosoides, is interpreted here as the reveliere together with Romaniceras kallesi and R. anus Event. It is inferred to correspond with the ornatissimum (Text-fig. 20). In France and in 2.5 m thick bed d of Unit C of the quarry La Spain the LAD of S. reveliereanus is in the level Tresorerie more or less simultaneously near of the turonienselhercynicus Event or a short Saumur, which is assigned to the basal turo distance above. In Germany, the first Inoceramus niense Zone. apicaZis and I. cuvierii appear more or less simultaneously in the hercynicus Event. In France the turonienselhercynicus Event can Lower Upper Turonian Event (LUTE) be recognized at Saumur (Saumurois) and near Taillebourg (Charante) in Aquitaine. In my opin This event is interpreted here as a tectonic ion, it lies in the uppermost 4.8 m of unit C of the event with inter-regional importance. Its culmi Tuffeau de Saumur in the quarry of Tresorerie, nation falls within the neptuni Zone and com south-east of Saumur (compare ROBASZYNSKJ & prises a set of tectonic activities that can be dated aZ. 1982, p. 131, Text-figs 3 and 5-6). From that to fall between the time-equivalents of the UPPER CRETACEOUS OF THE BARRANCA 205 German costellatuslplana Event (basal Upper extremely rare. The faunal composition and strati Turonian) and the Hyphantoceras Event (sensu graphical position of the event within the neptuni ERNST & al. 1983). It was, most probably, caused Zone suggest that it may equate with the by increasing tiltblock-halfgraben tectonics with H}phantoceras Event established by ERNST & al. in the Basco-Cantabrian Region. (1983) in Germany. The lithological and faunal In the Barranca, the LUTE is expressed by tec features of this latter event, were described from tonic uplift of the most eastern part, i.e. the area section in Lower Saxony (ERNST & al. 1983, between Sarasate and Urrizola, which generated WOOD & al. 1984, DAHMER & ERNST 1986) and turbidite sequences as well as extended hiati by from the Munsterland Cretaceous Basin (KAPLAN reworking in that interval. Contemporaneously, 1988, 1991). The Hyphantoceras Event can be the Estella area was affected by continuing subsi recognized throughout central Europe. dence, and here the LUTE is marked only by an In northern Spain, the inferred equivalent of the increase in the number of turbidites in the inter Hyphantoceras Event has so far been found only val between the geinitzii Bed and the in the continuous Ollogoyen section. From this Subprionocyclus I Event. Similar, time-equiva section, it is traceable to the Izurdiaga and Arardi lent, tectono-sedimentary events were also noted sections in outer shelf, albeit occupying local by WIESE (1997) in the North Cantabrian Basin swell positions with stratigraphically condensed (northern Cantabria, Spain), and may be successions. At Izurdiaga, two events, the geinitzii expressed by the tuffs in the north German sec Bed and the Subprionocyclus I Event, are proba tions. bly condensed and expressed by the so-called dev erianumlrhodanicum Event. This event yields an ammonite assemblage with R. deverianum, Scaphites geinitzii Bed Romaniceras sp., Puzosia sp., Puzosia muelleri and Tongoboryceras sp. in a distal position. This event marks the FAD of Subprionocyclus Towards the swell, in the more proximal Arardi neptuni in the continuous section of the Estella section it is expressed by reworking. The con area. Because of its bio- and event stratigraphical glomerate above the hardground (Ar-89) consists position, it is inferred to correlate with the level of glauconitized and phosphatized flat pebbles as of the German costellatuslplana Event sensu well as phosphatized ammonites, particular small ERNST & al. (1983), which was named after the sized Tongoboryceras spp. The faunal composi echinoid Sternotaxis plana and the inoceramid 1. tion, i.e. the presence of single 1. costellatus, costellatus. The FAD of the latter index species Neocrioceras (Schlueterella) cf. multinodosum was suggested as a basal boundary marker for the and Baculites undulatus, indicates the base of the Upper Turonian (BENGTSON 1996). This marker neptuni Zone as well as a higher level in the nep horizon was originally interpreted as an ecoevent tuni Zone. It is suggested that this level corre but, in condensed north-west German sections, it sponds to both the costellatalplanus and the is associated with a period of condensation and Hyphantoceras Event in German sense. The dev reworking. It has, consequently, to be interpreted erianumlrhodanicum Event of the Arardi section, in a wider, inter-regional, context. In marginal on the other hand, correlates with the so-called positions (e.g. Barranca), the Spanish geinitzii deverianum Event sensu WIESE (1997) in the Bed, falls in a hiatus induced by the LUTE (Text Santander area, Cantabria, which lies in the lower fig. 18) and it is expressed by the deveria part of the neptuni or neptunildeverianum numlrhodanicum Event. Assemblage Zone sensu WIESE (1997). Subprionocyclus I Event Coniacian - Santonian In a middle shelf position, this event is charac In the western Barranca, the Coniacian is rela terized by the first abundance peak of tively homogenous and developed in marly or Subprionocyclus spp. together with rare Scaphites calcareous marl facies. Between Satrustegui and sp. indet, R. deverianum and Hyphantoceras cf. Alsasua, the lowermost part of Lower Coniacian reussianul11 (Text-Fig. 15). Inoceramids is missing. South of Iturmendi, ZANDER (1988) (Mytiloides ex gr. striatoconcentricus) are reported a thickness of about 300 m for the 206 THOMAS KUCHLER Coniacian, of which ca. 100 m were Lower the name Izurdiaga Limestones for the succes Coniacian, developed in marly facies, and the sion of limestone and alternations of limestone remaining 200 m were Middle Coniacian, char and calcareous marls exposed at this locality, and acterized by calcareous marls. ZANDER (op. cit.) he suggested a Coniacian - Santonian age. This interpreted these sediments as shallow shelf interpretation was followed later by DEGENHARDT deposits. Further to the west, south of Olazagutia, (1983) who made a detailed lithostratigraphical at least in the lower part of the Dicarinella con study of the type section situated east of the cavata foraminiferal Zone (Middle to Late Alsasua - Pamplona railway. He, however, Coniacian) the foraminiferal associations reflect defined his base of the Izurdiaga Limestones con ed a deeper outer shelf position. siderably deeper than RADIG, at a level that is At Olazagutia, the Santonian reaches a maxi here placed within the Middle Turonian. mum thickness of ca. 230 m in the Quarry of the At Izurdiaga (see Text-fig. 27), the Izurdiaga Cements Portland S. A. Cantera de Margas Group shows an internal threefold subdivision. (KANNENBERG 1985, and Text-fig. 28B). GRAFE DEGENHARDT (J 983) recognized the following (1994), however, gives a Santonian thickness of units which are, in ascending order the Lower only 140 m for the same quarry, where he recog Izurdiaga Limestones, the Intermediate Marl nized the Lower Santonian (upper part of the and the Upper Izurdiaga Limestones. This sub Dicarinella concavata Zone) and the Upper division, derived from the topographic features Santonian Dicarinella asymetrica foraminiferal near Izurdiaga, was also applied to the expo Zone. According to that author the benthonic sures east and west of the type locality by KUHN foraminiferal associations of the asymetrica (1982) and KUCHLER (1983). However, the sig Zone suggested deposition in a deeper basin at nificant facies changes, i.e. decrease of thick about 500 m depth. nesses towards the east (Text-fig. 27), as well as Toward the east, in the direction of Irurzun, the the absence of several sub-units of the Izurdiaga thicknesses of both the Coniacian and Santonian Group due to hiati, were not fully recognized at decrease rapidly and the facies changes from marly that time. Consequently, each author interpreted sediments towards a calcareous, glauconitic facies and subdivided the Izurdiaga limestones differ (see Text-fig. 27). While near Zuazu the Coniacian ently. and Santonian still reach a thickness of about 200 At the type locality the Izurdiaga Group is and 100 m respectively, the thickness of both stages about 260 m thick. In the present paper, it is at Izurdiaga is reduced to ca. 248 m as a result of divided (in descending order) into three forma condensation and hiati. Tectonic movements of the tions: Ilsede Subhercynian Phase sensu STILLE (1924) caused uplift structures and led, in the eastern (i) Upper Izurdiaga Limestone Formation. Barranca, to strong facies differentiation towards a (ii) Zuazu Formation structural high, which is well documented by the (iii) Lower Izurdiaga Limestone Formation sections between the villages of Urrizola and Sarasate. The succession of thick-bedded lime The terms Lower and Upper Izurdiaga stones and alternations of limestones and calcare Limestones, used informally by DEGENHARDT ous marls in this area is referred to the Izurdiaga (1983), KUHN (1982) and KUCHLER (1983), are Group, which is described in more detail below. herein given formal formation status, albeit with revised definitions and limits. The newly introduced Zuazu Formation (herein) based on LITHOSTRA TIGRAPHY OF THE the sections at Zuazu, rather than on those at CONIACIAN AND SANTONIAN Izurdiaga, includes at the base the up to 30 m OF THE EASTERN BARRANCA thick Sternotaxis Marls, which were previously termed the Zwischenmergel (Intermediate Izurdiaga Group (Upper Turonian - ?Upper Marls) by KUHN (1982). At Zuazu a second Santonian) marly unit, the Micraster Marls, is separated from the Sterno taxis Marls by a unit of alter The type locality of the Izurdiaga Group is the nating calcareous marls and limestones. At the village of Izurdiaga, situated ca. 1.5 km south of type locality for the Izurdiaga Group, the Irurzun (Text-fig. 1). RADIG (1973) already used Sternotaxis Marls and part of the overlying unit UPPER CRETACEOUS OF THE BARRANCA 207 are missing at an hiatus, and here the marls unit Lower Izurdiaga Formation above the Lower Izurdiaga Limestones corre spond to the Micraster Marls of the complete The Formation consists of m-thick, nodular Zuazu section. limestones and alternations of thinly bedded The stratotype Zuazu Formation extends from a limestones with intercalated marls. Seven, in level within the upper Lower Coniacian part strongly glauconitic subunits can be recog Peroniceras subtricarinatum Zone to a level nized locally. In the type locality at Izurdiaga, within the Middle Santonian Texanites quin the formation is ca. 42 m thick (Text-figs 5,27). quenodosus Zone. The contact with the overly At Arardi, where it is rather poorly exposed it ing Upper Izurdiaga Limestone Formation can be reaches a thickness of ca. 31 m. At these two observed in the section south of Zuazu; at localities, as well as at Urrizola and Ecay, the Izurdiaga the contact has not yet been accurately formation forms a significant step in the land identified because of the lack of detailed studies. scape. However, it is placed at a distinct limestone boundary, i.e. at the base of bed IzI-153 (see Type locality - Izurdiaga: At Izurdiaga (see Text-fig. 27). Text-fig. 4) the base of the formation is defined by the appearance of the harder nodular lime Distribution: In its characteristic topographic stones of unit E2, the limestone bed of which is expression as a range of scarps, the Izurdiaga marked by a hardground (IzI-92). This level cor Group is limited to the eastern part of the responds to the boundary between the deveria Barranca. This chain of hills, composed of almost num and neptuni zones (Middle to Upper vertically dipping beds, strikes in a NNW - SSE Turonian). direction and accompanies the Sierra de The Lower Izurdiaga Limestone Formation is Satrustegui from Izurdiaga to Ecay. The range is composed of seven lithological units. However, also a part of the Sandaiia-Sollaondi Anticline only the lower four units (up to bed IzI-109a), (KUCHLER 1983), the northern flank of which is were investigated in detail. The description of the cut out west of Sarasate by the Irurzun - remainder of the succession and the lithological Larumbe Fault. Near Ecay, the Izurdiaga Group is subdivision are taken from DEGENHARDT (1983, cut off by a N-S trending fault. In the area west pp.45-48). of Zuazu - Satrustegui, the Izurdiaga Group is intensively folded and divided into blocks by Unit E2: This unit, 5.0 m thick, is composed of lime transverse faults. stones ("calcisphere" packs tones and echinoid debris Toward the west, the Zuazu Formation and the packstones) with cm-thick intercalations of calcareous Upper Izurdiaga Limestone Formation of the marls. The limestone beds are in part incipient hard Izurdiaga Group become more marly, simultane grounds (sensu KENNEDY & GARRISON 1975). ously increasing in thickness and grading lateral ly into the so-called Barranca Member and in the Unit F: This unit consists of a 7 m thick succession of Olazagutia Formation sensu AMIOT (1982). mainly nodular limestones ("calcisphere" packstones), of variable thickness, and with intercalations of thin Stratigraphical position of the Izurdiaga bedded calcareous marls. Group: Contrary to previous opinions of RADIG (1973), KUHN (1982), DEGENHARDT (1983) and Unit G: This unit is about 5.0 m thick and consists of a KUCHLER (1983), the lower boundary of the glauconitic alternation of thin-bedded calcareous marls Lower Izurdiaga Formation, as here defined, lies to marls (wacke-, pack- and grainstones) and nodular in the lower Upper Turonian Subprionocyclus (0.1-0.2 m) limestones. This unit includes the Turonian neptuni Zone. The formation extends up into the - Coniacian boundary, which is situated in the glau upper Lower Coniacian. The Zuazu Formation conitic marl of bed IzI -lOSd. starts in the upper part of the Peroniceras subtri carina tum Zone. The Upper Izurdiaga Formation Unit Izl-109a: This unit, ca. 1.1 m in thickness, is a is unsatisfactorily worked out at the moment, but highly glauconitic, silty biomicritic wackstone to pack it starts in the Middle Santonian Texanites quin stone. Its thickness rapidly decreases westwards, so quenodosus Zone and probably extends up into that in Urrizola W section, it is only 0.6 m thick (Text the Upper Santonian. fig. 27). 208 THOMAS KUCHLER Unit IzI-I09: This is a ca. 8.0 m thick unit, composed nodular limestones and calcareous marls of vary of nodular limestones, separated by thin horizons of ing thickness. calcareous marls. Unit 120 is followed by the overgrown ca. 29 m thick Intermediate Marl (Iz-123), correlated here Unit IzI-(llO-1l2): The ca. 5 m thick unit is composed with the Micraster Marls (Member C) of Zuazu of bedded limestones, producing a negative topogra (compare Text-fig. 21). The upper part of the phic feature. Izurdiaga section was not investigated in this study. The next unit is a ca. 57 m thick succesion (Iz- Unit IzI-114: This is aILS m thick unit of poorly bed 124 to Iz-153), composed ofm-thick, hard, nodu ded limestones. lar calcareous marls, intercalated in softer cal careous marls with, in the basal and middle part, Reference section - Arardi: (Text-fig. 3): The intercalations of thin, glauconite calcareous base of the formation is again marked by a lime marls. stone bed with a hardground at its top. At Arardi, however, this bed is succeeded by an Upper Izurdiaga Formation horizon of hiatus concretions (Ar-90). The basal bed is followed by a poorly exposed alternation Based on the investigation of the sections near of 0.3 to 0.4 m thick limestones and marls (0.1 Zuazu, the threefold division of the Izurdiaga m). The upper part of these ca. 31 m thick lime Group is maintained, despite the fact that stones is eroded or overgrown. already at its type locality, and still further to the east, this subdivision becomes less clear Zuazu section: In this section, which, in con because of the increasing extent of the hiati and trast to the Izurdiaga and Arardi sections repre rapid lateral facies change. This means that sents a more distal situation, the equivalents of there is an amalgamation of the formations in the Lower Izurdiaga Formation are represented this direction. by a ca. 43 m thick alternation of light grey, platy, up to m-thick calcareous marls and nodu Type locality - Izurdiaga (Text-fig. 27): At lar, 0.1-0.2 m thick marly limestones of the Izurdiaga, DEGENHARDT (1983) placed the base Upper Coniacian Peroniceras subtricarinatum of the Upper Izurdiaga Limestones immediately Zone. above the so-called Intermediate Marl, i.e. at a much lower level than that adapted here (base of Zuazu Formation IzI-153). However, his section is very useful because it is extremely detailed. The Zuazu Formation was defined south of the The Upper Izurdiaga Formation (Text-fig. 27) village of Zuazu (Text-fig. 1). It consists of starts with a ca. 40 m thick unit of hard, in the light calcareous marls, dark marls and interca upper part of well bedded, limestones, contain lated light, nodular limestones. It reaches a ing, according to DEGENHARDT, two pebble - maximum thickness of approximately 180 m. beds in its topmost 6 m. The ca. l.0 m thick top bed (Iz-162) is strongly glauconitic. Type locality Zuazu: Details of the stratotype The succeeding unit is ca. 85 m thick. The low Zuazu Formation are given later in this chapter, est part consists of a marly interval of ca. 4.0 m. by a description of the localities Zuazu Band C These are followed by harder, nodular calcareous (see Text-figs 21-22). marls, alternating with up to m-thick, softer cal careous marls. There are also some l.0 to 2.0 m Izurdiaga section (Text-fig. 27): Near Izurdiaga, thick weakly to highly glauconitic beds. The top the Zuazu Formation overlies the Lower most part of the unit is developed as 14-15 m Izurdiaga Formation (unit 114) with a hiatus, thick interval of nodular, harder calcareous marls comprising the so-called Sterno taxis Marls or nodular marly limestones, which become (Text-figs 21,27, and DEGENHARDT 1983, Text increasingly glauconitic upwards. fig. III3). The ca. 8.0 m thick Unit 120 probably represents Member B (subunit B2) of Zuazu. It Zuazu: Near Zuazu, the Upper Izurdiaga starts with a conglomerate of limestone pebbles Formation already begins to resemble the rhyth and is mainly composed of an alternation of mically bedded at least 85 m thick, lime- UPPER CRETACEOUS OF THE BARRANCA 209 stone/marl succession of the western Barranca as Up to the middle 1980s, the Zuazu B section seen in the Olazagutia quarry, and referred herein was comparatively well exposed. Later, however, to the Olazagutia Formation (Text-fig. 28B) of its upper part was destroyed by a newly con AMIOT (1982). structed field road. The beds of the Zuazu B sec tion dip almost vertically (80-90°). The exposure is limited by a fault zone. SELECTED SECTIONS OF THE EASTERN The investigation of the Zuazu sections was BARRANCA supplemented by a second exposure, the Zuazu C section (Text-fig. 22), situated on a small eleva Zuazu Band Zuazu C (upper Lower tion between the two brooks, ca. 850 m south of Coniacian - Middle Santonian) Zuazu. The base of the Zuazu C section lies south of the fault zone at an altitude of 540 m.The beds Location dip 30 to 40° to SE. In the area between Ecay and Satrustegui the (a) Zuazu B section (Text-fig. 21): Topogra Coniacian reaches ca. 200 m in thickness, with a phical map Ecay 114-12, 1:10 000, R=591.830, particularly thick upper Lower Coniacian reach H=4.750.970; base of the section about 650 m ing alone ca. 150 m. The Santonian attains a south of the exit from Zuazu. thickness of about 100 m, but only its lower part (b) Zuazu C (Text-fig. 22): Topographical has been investigated in detail. map Ecay 114-12, 1:10 000, R=591.740, The upper Lower Coniacian is characterized by H=4.750.740; base of the section about 850 m small hiati. A major hiatus occurs in the south of Zuazu. Coniacian/Santonian boundary interval. This hia tus is designated here by the term ULSE (=Upper General remarks Lower Santonian Event). The upper Lower Santonian or Middle Santonian (Texanites quin South of the small village of Zuazu/Araquil quenodosus Zone) discordantly overlies strata there are several natural exposures. The beds dip belonging to the Upper Coniacian Protexanites gently at a low angle and comprise a normal suc bourgeoisi Zone, the latter corresponding to the cession, ranging stratigraphically from the Lower lower part of the Upper Coniacian Paratexanites Coniacian to the Middle Santonian. The locality serratomarginatus Zone sensu KENNEDY names Zuazu A and Zuazu B are taken from (l984a). KUHN (1982), who investigated the succession for the first time in this area. He dated it broadly Lithostratigraphy as Coniacian and gave only a rather rough pre sentation of the sections. The illustrated succession of the Zuazu B sec At Zuazu, the Lower Izurdiaga Formation com tion, ca. 97 m in thickness, starts about 4 m prises a unit of calcareous marls and therefore no below the base of the Zuazu Formation (0 m level longer forms a positive features. The land rises in Text-fig. 21). The whole of the Lower gently towards the south, but with the onset of the Izurdiaga Formation, ca. 43 m thick at Zuazu, is limestones of the Santonian Upper Izurdiaga not shown. The boundary between the Lower Formation, a scarp feature attaining a considerable Izurdiaga Formation and the Zuazu Formation is altitude (ca. 700 m) is developed. The basal exposed about 630 m south to south-east of Coniacian, indicated at Izurdiaga by the Zuazu. It is characterized there by a distinct Cremnoceramus rotundatus and Forresteria lithological change from marl-limestone alterna petrocoriensis zones, is missing at Zuazu. The tions to weakly lithified, dark marls. To the west, Zuazu B section starts in the upper Lower these marls are deeply incised by a brook that Coniacian Pironiceras subtricarinatum Zone flows parallel to the strike of the beds. (Text-fig. 21), as indicated by the presence of Peroniceras subtricarinatum (D' ORBIGNY), Lower Izurdiaga Formation: Near Zuazu, distal Cremnoceramus deformis (MEEK), and C. crassus equivalents of the Lower Izurdiaga Limestones (PETRASCHECK) The succession is overthrust onto overlie probable Santonian limestones at a tec limestones of presumed Santonian age, so that the tonic contact. Above the contact, an up to 1.6 m Coniacian succession is limited tectonically. thick limestone bed pinches out to the west and 210 THOMAS KOCHLER 1"",,,,,,,,,,,,,,,,,,,,,,,,'1 marl frequency of specimen • rare (1) fl ca~reous marl ~ • common (2-5) f!! ~ marly limestone • abundant ( >5) tJ!! E5::9 Ifmestone nodular limestone. i-:gii=i limestone nodules LlLF Lower lzurdiaga Limestone Formation U1LF ZUAZUB Echinocorys gravest EVent ~~~~~)£,,~!i::~~~1~~1~-;-;:;l~-;:;-;:;-;:;-;:;l~1~:1-;:;-;1-;:;-;:;11l~11~1~-;:;-;:;-;:;-;:;-;:;-;:;-;:;-~CBrdiotllxiSMlcrsster maximum Integer Bed ~ Cr. "deformls" II Event ILeE Echlnocorys gravesV Csrdiotsxis Integer Bed Cr. "deformls" I / Ansgaudrycerss sp. Event TKO 96/98 Fig. 21. Zuazu B section; litho-, bio- and event stratigraphy in the Lower Coniacian (Peroniceras subtricarinatum Zone); local ranges of ammonites, inoceramids and echinoids, the latter group without the Mieraster, the most abundant taxa throughout the section UPPER CRETACEOUS OF THE BARRANCA 211 ZUAZUC Ammonites Echinoids IEvents and marker beds not exposed 366 i-"-~·..,.--~---c~~~~~~~~-""+~I-4II"---j) Offaster nUGlform/s II Event 2,5 i{·.,·r··.ii.·im.·tt', 0,3 0,7 Hg340 ~'Cf:a~;=,:s::,=t=E~;=,;=,;=,===!==l=~===p Tndenticeras II Event f-- 135 0.1 -~ 1 " .- - - 338 0,b,8 " N N _~ 130 1,8 1 = 1,5 " " ~ - 1,9 " . --- (J!! 335 4--'---_"--+-t-:------l-_l_iI----.-.-kl Pfafyceramus? bed 2,4 - 1125 • - - . 1,0 N . ~ ~:~ 3:1 - 331 4-·--...-- .....------.. -.. ·--l--HI--·---p Tfldenticeras I Event 1120- 0,4 . fll.. 327 3,7 " 0,2 03 325 0,20'4 gravesi II! 321 ~"vont 0'20~~ 319 '0,9 (J 315 314 0:6 0,3 311 01 0,81,1 =~-~.= (J- 0,8 309 - 1,3 0.1 · - 308 0,9 1105 10,1 · " 3,4 " - -.. - 307 0,4 306 " - 1100 - 5,7 . - " - - 3041... ~~------+_l_i~---, 300 4-~------+.. 1---...__\: Echinocorys gravesi I Event 29&f~----·+--..----·------+4H~--~ 296 1,2 N 80 0,6 - 1 0,9 4,0 . · . - · - " TKfi 96/98 Fig, 22. Zuazu C section; litho-, bio- and event stratigraphical subdivisions of the Lower Coniacian to Middle Santonian succession; vertical ranges of selected macrofossil groups; the echinoids presented without the most abundant Micraster genus 212 THOMAS KUCHLER east, rendered conspicuous by its yellowish ually upwards into calcareous marls. About 14-15 m weathering colour, as well as by the limonitised above the base of the unit sponges become common. concretions on its upper surface. The Lower Izurdiaga Formation is composed Spongiolithic calcareous Marls (= Member D): It is a of a ca. 43 m thick alternation of light grey, platy, ca. 41 m thick series of light grey, platy, calcareous up to m-thick calcareous marls and nodular, ca. marls weathering yellowish to dark grey, with interca 0.1-0.2 m thick marly limestones. Groups of lations of nodular, 0.1 to 0.3 m thick marly limestones. limestone beds together with single dm-thick cal The calcareous marls sometimes build more resistant, careous marls build topographic ribs, on average up to m-thick beds, which form topographic steps and 1.4 m thick. At least the upper part of the forma ribs. The beds ZuB-lSS (=ZuC-296), comprising five, tion at Zuazu may be referred to the upper Lower closely-spaced thin limestone beds, is recognizable as Coniacian Peroniceras subtricarinatum Zone. far as Satrustegui and may be used as a marker horizon. The characteristic feature of the whole unit is the abun Zuazu Formation: The Zuazu Formation is com dance of siliceous sponges. posed of eight lithological units, characterized (in ascending order) below (Text-figs 21-22). gravesi Limestone/calcareous Marl alternation (= Member E): This 8 m thick succession (ZuC-309 to (viii) Offaster Marls (= Member H) ZuC-32S) is composed of 0.1-0.2 m thick limestones or (vii) Nodular limestone Unit (= Member G) marly limestones and calcareous marls with upward (vi) Calcareous marl Unit (= Member F) decreasing bed thicknesses. These are sporadic, m (v) gravesi Limestone/calcareous Marl alternation thick intervals of harder calcareous marls. The lime (= Member E) stone bed ZuC-321 is slightly glauconitic. The member (iv) Spongiolithic calcareous Marls (= Member D) is characterized by the common occurrence of (iii) Micraster Marls (= Member C) Echinocorys gravesi. (ii) Calcareous marl/Marly limestone Unit (= Member B) Calcareous marl Unit (= Member F): This 20 m thick (i) Sternotaxis Marls (= Member A) unit (ZuC-326 to ZuC-340) is composed of light grey, platy calcareous marls, rich in Micraster spp. and Sternotaxis Marls (= Member A): The Sternotaxis sponges. The sponges are represented by cup- or Marls correspond to the Intermediate Marl of KUHN mushroom-shaped as well as branching forms. Layers (1982) and have a thickness of about 24 m at Zuazu. of large-sized, thin-shelled inoceramids are charac The member, composed of dark grey brittle marls teristic. The member terminates in a hardground (4.4 to 6.0 m) with thin intercalations of harder, (ZuC-340). platy marls tones , overlies the Lower Izurdiaga Formation with a slight angular unconformity. The Nodular limestone Unit (=Member G): This 20 m thick unit takes its name from the occurrence of the large unit forms a positive topographic feature. Its lower part sized Sternotaxis aff. placenta AGASSIZ. Micraster is composed of up to m-thick, more resistant intervals ex gr. cortestudinariul11 is, however, much more consisting of several closely spaced layers of limestone common. nodules separated by dark grey calcareous marls (2.5 m). In contrast, the upper, ca. 5.0 m of the unit com Calcareous marl/Marly limestone Unit (= Member B): prises an alternation of closely-spaced (0.1-0.2 m) cal This unit, 22 m thick, is bipartite. Its lower, 10 m thick Cal'eous marls and nodular, marly limestones. The part (ZuB-108 to 124) called B 1, represents a thicken marly limestones have a characteristic yellowish ing upward sequence, composed of dm-thick calcare weathering colour. Near Zuazu, the unit starts in the ous marls and well-bedded dm to m-thick limestones. upper part of the margae Zone and extends up to the The upper part, B2, is dominated by calcareous marls, top of the Protexanites bourgeoisi Zone. with m-thick beds, and with intercalations of well-bed This member probably corresponds to that exposed ded, dm-thick limestones. The top bed ZuB-138, 0.5 m in the road section at the pass towards the Urbasa, south thick, is a useful marker horizon. of Alsasua (compare ZANDER 1988) and to the Upper Coniacian alternation exposed in the Olazagutia quarry. Micraster Marls (= Member C): This unit is a 19 m thick interval, of grey marls, characterized by the abun Offaster Marls (=Member H): In its lower part, the dance of the echinoid Micraster. The marls pass grad- unit consists of dark grey marls to calcareous marls UPPER CRETACEOUS OF THE BARRANCA 213 in a thickness of ca. 6 m. Intercalated in the marls Barranca may be considered as a direct strati are sporadic, m thick beds of limestones nodules. graphical link between the French localities and Above follows light grey marls ca. 8 m-thick, with the Spanish Burgos area with its local zones sporadic intercalations of thin limestones. The index (WIEDMANN 1960, 1965, 1979b), which could not echinoid Offaster nuciformis ERNST is common over hitherto be correlated with those of the regions to an interval of ca. 15 m. The top part of the unit is the north. composed of a ca. 4 m thick closely spaced alterna The upper Lower Coniacian yields a low tion of dark grey marls (0.1 m) and 0.05-0.08 m thick diversity Scaphites - Peroniceras assemblage, nodular, marly limestones, as well as beds of lime with tissotiids occurring extremely rarely in the stone nodules. highest part of the substage. The ammonite diversity increases in the Middle Coniacian, Upper lzurdiaga Formation: At Zuazu, a succession of where the ammonite fauna is characterized by a thick bedded limestones, referred to the Upper Scaphites-Tridenticeras-CIauthiericeras assem Izurdiaga Formation, forms the next significant step in blage. The diversity - decreases again in the the landscape. Upper Coniacian, being characterized by the genera Protexanites, Gauthiericeras, Baculites Fauna and biostratigraphy and Scaphites. Irregular echinoids: The succession at Zuazu Inoceramids: The inoceramids discussed here is extraordinarily rich in irregular echinoids. The were determined by C. J. WOOD (Croydon, UK) dominant genus Micraster exhibits many acme and I. WALASZCZYK (Warsaw). Mytiloides stria occurrences. However, these have not been toconcentricus ranges up to the upper part of the incorporated into the event stratigraphic frame Peroniceras subtricarinatum Zone, in the Ecay work, nor have ranges of indicated taxa been E section up to the Echinocorys gravesi II given, because a detailed taxonomic treatment of Event. Representatives of the Cremnoceramus this group has not yet been carried out. waltersdOljensis group disappear already earli Echinocorys gravesi (DES OR) and Cardiotaxis er, in the defonnis II Event (see Zuazu B sec integer (AGASSIZ) have long stratigraphic ranges, tion). The Cremnoceramus erectus - deformis but in contrast to Micraster, they show acme lineage and C. crass us first appear together with occurrences only in a few distinct beds. Peroniceras subtricarinatUln, in the lower part Echinocorys has four acme-occurrences, each of of the Peroniceras subtricarinatum Zone within which is characterized by different morphotypes the Lower Izurdiaga Formation at Zuazu (not and sizes. figured). Late cremnoceramids as well as P. sub The genus Sterno taxis, represented by tricarinatum were still found in the Sterno taxis aff. placenta (AGASSIZ) is limited Gauthiericeras margae Zone, in the Zuazu A to the middle part of the Lower Coniacian section just below above the Tridenticeras II Peroniceras subtricarinatum Zone, while Event. Hemiaster ranges from the Middle Coniacian In the subtricarinatum Zone, inoceramids Gauthiericeras margae Zone up to the Middle occur in the topmost 4.2 m of the Lower Santonian. The genus 0ffaster, with the Izurdiaga Formation, between beds ZuB-98 and species Offaster nuciformis, first appears in an ZuB-lOOe, and in the basal part of Member D of stratigraphically uncertain interval between the the Zuazu Formation, between beds ZuB-140 and upper Lower and the lower Middle Santonian. ZuB-148 (see Text-fig. 21). In the basal part of the G. margae Zone, inoce Ammonites: The Coniacian succession of Zuazu ramids occur between beds ZuC-309 and ZuC- is of considerable biostratigraphical importance, 321. Layers of thick-shelled inoceramid frag on the one hand because of the co-occurrence of ments (probably Platyceramus? sp.) are abun inoceramids and ammonites and, on the other dant in an interval between beds ZuC-327 to hand because of ammonite assemblages that ZuC-33l, around the Tridenticeras I Event show great similarities to those of the French (Text-fig. 22). Single finds from bed ZuC-331 type region of the Coniacian. This permits a cal may represent Inoceramus cf. percostatus ibration of biostratigraphical frameworks MOLLER or forms close to Cremnoceramus aff. between these two areas. Additionally, the inconstans according to TRaGER (pers. cOlnm.). 214 THOMAS KUCHLER Event stratigraphy gravesi III Event: The gravesi III Event is char acterized by two distinct maxima of Echinocorys The exposures around Zuazu yield a sequence gravesi within an interval of 1.1 m (ZuC-319 to of marker-beds that have potential for regional ZuC-321), the latter being accompanied by a correlation within the Barranca. Additionally, Micraster-acme. The event lies at the top of the some of these events can be shown to have an Member E. interbasinal importance as they permit a precise dating and correlation of major tectono-sedimen Tridenticeras I Event: It is a ca. l.0 m thick, cal tary events, related to relative sea-level changes careous marl (ZuC-331) with an accumulation of (for discussion see further below). large undetermined inoceramids. It is character ized by the abundance of almost exclusively deformis IIAnagaudryceras sp. Event: This event heteromorph ammonites of the genus Tridenti is defined as an event-set, characterized by the ceras (juvenile Tridenticeras sp., Tridenticeras common occurrence of the two eponymous taxa, varians). This level marks the local FAD of the the inoceramid Cremnoceramus deformis and a genus Tridenticeras. specifically indeterminate Anagaudryceras, at its top. At Zuazu, the event set comprises a 1.4 m Platyceramus? Bed: It is a prominent plaster of thick interval of calcareous marls with 0.1-0.2 m large inoceramids within a l.9 m thick calcareous thick intercalations of nodular limestones. Small marl bed (ZuC-335). Mytiloides striatoconcentricus are concentrated in two limestone beds at the base and at the top. Tridenticeras II Event: This is a fossiliferous Micraster sp. is abundant in the basal, 0.8 m part, interval (ZuC-340a) between a nodular limestone of the event. Throughout the interval ammonites and a marly limestone bed. The lower of these are common, particularly Anagaudryceras sp. beds is a 0.1 m thick incipient hardground. The intervening marl (ca. 0.3 m), as well as the higher gravesilinteger Bed: This is a local acme-occur limestones, are both very fossiliferous, yielding rence of Cardiotaxis integer and Echinocorys abundant inoceramids and an ammonite fauna gravesi, found in bed ZuB-125, which is a 0.3 m dominated by tridenticeratids and scaphitids. The thick calcareous marl. This bed and the underlying assemblage comprises Scaphites kieslingswalden 0.9 m thick limestone serve as marker horizons for sis, Yezoites cf. arnaudi, Gaudryceras sp., correlation of the exposures around Zuazu. Hauericeras sp., Tridenticeras varians, T. tri dens, T. sp., and Hyphantoceras plicatum. deformis II Event: This inoceramid-rich horizon lies ca. 8 m above the base of Member D. It Echinocorys IV Bed: The fourth Echinocorys yields Cremnoceramus cf. rotundatus as well as gravesi maximum is recognized around bed poorly preserved C. waltersdorfensis han ZuC-344. novrensis and C. cf. waltersdorfensis han novrensis. The inoceramid abundance varies boreauilbourgeoisi Event: This event is defined markedly over a lateral distance of only a few by the abundance maxima of the two eponymous metres. As in the Ecay E section (Text-fig. 24). ammonites ?Gauthiericeras boreaui and There is an abundance maximum of Micraster ex Protexanites bourgeoisi as well as Baculites gr. cortestudinarium above the deformis II incurvatus within a 0.7 m thick interval (ZuC- Event. 346 to ZuC-349). The event interval consists of two limestone beds and a calcareous marl Cardiotaxis integer Bed: At Zuazu, this between. The lower limestone bed yields Cardiotaxis-rich horizon is located above the siliceous sponges, and the second (ZuC-349) is defonnis II Event and Micraster-acme event additionally characterized by bivalves. bundle. Offaster nucifonnis I Event: It is a level of a mass Echinocorys gravesi II Event: The second occurrence of irregular echinoids of the genera gravesi maximum lies ca. 18.7 m above the Offaster and Hemiaster, in a stratigraphically Cardiotaxis integer Bed, around a 0.6 m thick uncertain position between the upper Lower and horizon (ZuB-163; = ZuC-300). lower Middle Santonian. Near Zuazu, of the UPPER CRETACEOUS OF THE BARRANCA 215 genus Hemiaster is more common than the Text-fig. 33). The beds are overthrust and dip eponymous Offaster nuciformis within the l.9 m northeast 30°. thick interval (ZuC-364) of dark grey marls and The base of the measured section is taken at a nodular limestones. nodular, marly limestone bed (ZuA-200) that forms a conspicuous rib in the gully. The interval Offaster nuciformis II Event: The second from bed ZuA-200 to ZuA-205 correspond to the Offaster-acme (nuciformis II Event) lies ca. beds Az1 to B500 sensu KUHN (1982) and falls in 3.0 m above the first one in a ca. 0.7 m inter the Middle Coniacian margae Zone. val. It coincides in Zuazu with the first re cord of Texanites cf. quinquenodosus (RED Lithology TENBACHER) . In the gully, grey blue, platy marls to calcareous Zuazu A (Middle Coniacian, margae Zone) marls are exposed with intercalated layers of limestone nodules. In the upper part of the section Location and remarks four marly limestone beds are developed, one of which, bed ZuA-205a represents the lateral equiv Erosional gully 350 m south of Zuazu/Araquil, alent of hardground Hg340 (Tridenticeras II west of the track leading to the Sierra de Event) of the Zuazu C section (Text-fig. 22). Satrustegui (Topographical map Ecay 114-12, 1:10 000, R= 591.750, H= 4.75l.220). Fauna Text-fig. 23 shows the upper part, ca. 13 min thickness, of a 100 m thick Coniacian succession Siliceous sponges: Siliceous sponges occur com investigated previously by KUHN (1982, p. 48, monly throughout the entire section. Ammonites Inoc. Ech. Events and marker beds limestone nodules nodular limestone limestone bed ~_::;;;::] lime marl frequency of specimen • rare (1) • common (2-5) &:1, • abundant ( >5) ll·· ZUAZUA .------. m - m t--.. _--="'-:-._-.__ .-...'N"'.- ....-._.-=-rx.c-_" ... 207 10- 1.4 N i 206 - 0.4 d _ 0,4 N N ~ 'ecb fl205~~~*~~~g~~~i-i~~c---;,iS.b,F ~ Tr;denticeras II Event 0.4 fl' - . '--N'-'~-r\-tl1!! .• Platyceramus Bed - BSOO N i iu 5 - 5,2 - N ~ \ 0':4 ... -",_ ... _..':': .. _.. o o~ig AZI N N fl 200 _ ammonite bed ~=:,,==~= r /V rv IV \ TKii 96/98 Fig. 23. Zuazu A section; lithology, bio- and event stratigraphy in the Middle Coniacian Gauthiericeras l11argae Zone 216 THOMAS KUCHLER Echinoids: Among irregular echinoids, Micraster thiericeratids and tridenticeratids. Inoceramids dominates the echinoid fauna. Echinocorys are represented by Cremnoceramus defonnis and gravesi occur only in the two, closely spaced beds Platyceramus ?mantelli. As in the Zuazu C sec in the lower part of the section tion, a limestone with a firmground and pyrite concretions is developed immediately beneath. Inoceramids: The upper part of the section is characterized by beds with large-sized inoce ramids (probably Platyceramus), associated with Ecay E (Lower Coniacian, Peroniceras late Cremnoceramus. In bed ZuA-205 a single subtricarinatum Zone) specimen of P. ?mantelli MERCEY was found. WALASZCZYK (pers. comm. 2/95) determined two Location additional specimens from bed B500 and from ZuA-205 as Cremnoceramus crassus Calcareous marl rib (Text-fig. 24) about 200 m (PETRAS CHECK) and Volviceramus cf. koeneni (G. east of the village Ecay (Araquil) (Topographical MULLER) respectively. This is the first record of map Ecay 141-12, 1: 10 000, R=593 000, H=47 Volviceramus koeneni from Spain. 51 350). Ammonites: Ammonites, with the exception of General remarks Scaphites kieslingswaldensis are limited to dis tinct beds. Characteristic forms of the margae Upper Cretaceous strata, from the Upper Zone comprise Gauthiericeras? boreaui (DE Cenomanian to the upper Lower Campanian are GROSSOUVRE), Tridenticeras varians (SCHLUTER) sporadically exposed in a N-S trending section and Tridenticeras tridens (SCHUlTER). There are (Text-figs 1,27). The Izurdiaga Group forms three also single finds of Eupachydiscus isculensis conspicuous NW-SE ridges that are abruptly trun (REDTENBACHER), Peroniceras subtricarinatum cated to the west at a NNE - SSW fault. Locally, and Neocrioceras (Schlueterella) cf. compres its thickness is reduced to about 200 m by several sum KLINGER. NNE - SSW faults, running almost parallel to the strike. A major fault brings Cenomanian Flysch a Event stratigraphy bouIes into tectonic contact with the Lower Izurdiaga Formation (Text-fig. 27). Ammonite bed: This is a ca. 0.2 m thick, nodular The Lower Izurdiaga Formation forms the north limestone bed (ZuA-200), which yields ernmost scarp in the landscape. It reaches a thick Gauthiericeras? boreaui, Scaphites kies ness of ca. 60 m and consists of an alternation of lingswaldensis and Eupachydiscus isculensis. hard limestones and calcareous marls, dipping at 80° towards the south. Because the lower part of the Echinocorys gravesi IIIb Event: About 0.8 m formation is tectonically disturbed and the upper 25 above the ammonite bed, there is a ca. 1.0 m metres are to some extent overgrown detailed thick interval (ZuA-202 to ZuA-203a) with abun investigation proved difficult. Approximately dant small-sized, and followed by large-sized 200 metres to the east, the highest part of the suc Echinocorys gravesi. There is also a Micraster cession yielded an ammonite-inoceramid assem acme. blage similar to that of the deformislAna gaudryceras Event of Zuazu, thus indicating the Inoceramid bed: This bed is characterized by Peroniceras subtricarinatum Zone. Micraster spp. large, thin-shelled inoceramids, directly above occurs commonly throughout the entire section. the gravesi maximum. The Lower Izurdiaga Formation is probably overlain by the Sterno taxis Marls. This member Platyceramus Bed: A conspicuous bed of large, of the Zuazu Formation is poorly exposed and thin-shelled platyceramids, intercalated within also tectonically reduced (compare Text-fig. 27). calcareous marls, about 0.4 m below the Tridenticeras II Event. Litostratigraphy Tridenticeras II Event: This event represents an Spongiolithic calcareous Marls (Member D): The accumulation of ammonites with abundant gau- second distinct elevations east of Ecay consists of UPPER CRETACEOUS OF THE BARRANCA 217 Ammonites Echinoids Events and marker beds frequency of specimen • rare (1) limestone bed • common (2-5) &::! I~ ~I lime marl • abundant (>5) l!!! marly limestone ECAY E rn- o _ gravesi II Event - - - T - 7,0 5 _ - - - \ - 10_ - 4,4 - 1,2 - N§§-N _.cardiasterinteger _ 0,6 -- - i.iii)·····················\ maxnnum 0,9 N 15 - ~ N N N : , _ 0,8-1,0 E[\2q N I N I N J j ~: : Micras.fer spp. - 1,2-1,4 ( maxnnum rc ~ .--: N~.-c: \ ······l.%T·················I-I···_·········~···~········.. _...... ->-.:' ..•• _.•.....•• --=-- ...... '---''--_-+-__.~:I-__1;?? inoceramid bed - 0,6-O,8l" {9' ; 1 - - - 1 1 ; ..:. ammonite bed 1 20 - N N N 0 I. I. l _ 4,2 ~ -=- ~ -= ~~ f7 I---i------I-----l------ID deformis bedll - - 1,2 l~f .. _------N-._----._-N-_ ._ .... __ .. __\-\ - 1", !~ - - \ 25 - 1,5 I~f-N" :strr1········-··-···_·-··_···--_··--\\ N N - +------~ - 1,3 I=I-~r=-:;:=-r::::;::=-r=~\ - 2,0 N N N N N N N - N N -"" I"" I \ Fig. 24. Ecay E section; lithology, macrofossil occurrences and event stratigraphy in the Early Coniacian Peroniceras suiJtricarinatum Zone 218 THOMAS KUCHLER light grey, platy calcareous marls. They are well abundant, small-sized Micraster ex gr. ?cortestu exposed over an interval of ca. 30 m in the figured dinarium. The Micraster acme is traceable 1.4 section (Text-fig. 24). The calcareous marls, charac km towards the east to the Urrizola W exposure terized by abundant siliceous sponges, include a few (see Text-fig. 27) as well as to Zuazu B (ZuB- 0.1 m thick, nodular intercalations of hard marly lime 149). stones. Tbe more resistant parts of the calcareous marls, form distinct steps in the field. For further sub Cardiotaxis integer Maximum: Cardiotaxis inte division the event occurrences of Cardiotaxis integer ger occurs abundantly within a ca. 2.7 m thick and Echinocorys gravesi were used. interval. Fauna and biostratigraphy gravesi II Event: As at Zuazu and at Urrizola W (see Text-fig. 27), this Echinocorys bed similar Ammonites: The ammonite association is domi ly follows the Cardiotaxis Event. nated by scaphitids and peroniceratids [Peroniceras subtricarinatum (PI. 12, Fig. 4), Peroniceras sp. Uuveniler)], with the occurrence INTEGRATED BIOSTRATIGRAPHY and abundance of Scaphites kieslingswaldensis LANGENHAN & GRUND AY being directly linked to Definition of the stage and substage the sponge facies. Ammonites occur mainly, boundaries albeit not commonly, in the lower third of the sec tion. (Text-fig. 24) Tissotioides haplophyllus Turonian/Coniacian boundary (REDTENBACHER) (PI. 13, Figs 1-2) appears in the upper part of the section. The base of the Coniacian is defined by the FAD The section represents an interval in the upper of Cremnoceramus rotundatus (sensu TRaGER non Lower Coniacian subtricarinatum Zone, compa FIEGE) (KAUFFMAN & al. 1996). In northern Spain, rable to the interval from ZuB-140 to ZuB-163 of the boundary, thus defined, approximates to the Zuazu (compare Text-fig. 21). level of the so-called Didymotis II Event (KUCHLER & ERNST 1989, WIESE 1997), in a similar manner to Inoceramids: Finely-ribbed forms occur, needing the situation at the proposed boundary stratotype detailed determination. section in the Salzgitter-Salder limestone quarry in northern Germany (WOOD & al. 1984, KAUFFMAN Echinoids: The echinoid fauna is represented by & al. 1996). In the Barranca, a comparatively com Micraster ex gr. cortestudinarium, Cardiotaxis plete, but condensed Turonian/Coniacian boundary integer, and Echinocorys gravesi. interval is exposed only near Izurdiaga (Text-fig. 5). Throughout the Barranca, the basal Lower Event stratigraphy Coniacian is missing due to tectonic and strati graphical gaps. At Izurdiaga, the boundary interval deformis bed II: The large inoceramids of this is marked by an equivalent of the Didymotis II bed have not got yet been determined. However, Event, characterized by an only cm-thick bivalve the position of this bed, ca. 5.4 m below the accumulation, with the index inoceramid appearing Cardiotaxis integer maximum, indicates that it only a few cm higher. equates with the Cremnoceramus deformis Event II of Zuazu B. Lower/Middle Coniacian boundary Ammonite bed: This is a level with juvenile Following the proposal of the Brussels Peroniceras sp. and Scaphites kieslingswaldensis. Symposium, September 1995, the base of the Middle Coniacian is defined by the FAD of Inoceramid bed III: Small, finely-ribbed inoce Volviceramus koeneni (G. MULLER) (KAUFFMAN ramids, possibly Mytiloides striatoconcentricus & al. 1996). characterizes this horizon. In northern Spain, this boundary is marked by the entry of the Platyceramus mantelli group, Micraster-acme: This is a 1.2 m thick interval approximately at the same level as the first between the S and X horizons characterized by Gauthiericeras margae (SCHLUTER) and the last UPPER CRETACEOUS OF THE BARRANCA 219 peroniceratids (compare KUCHLER & ERNST (LAMOLDA & HANCOCK 1996). Due to the inferred, 1989). This boundary agrees with that in continuous succession across the Coniacian/San Germany, which is taken at the entry of vol vice tonian boundary interval, and the associated inoce ramids (compare TRaGER 1989). The German ramid fauna, the Olazagutia quarry was proposed Middle Coniacian inoceramid assemblage addi by ERNST (in SCHULZ & al. 1984) as an interna tionally in1cudes Platyceramus of the mantelli tional boundary stratotype (BIRKELUND & al. 1984, group, which can occur together with vol vice LAMOLDA & HANCOCK 1996). This quarry ramids at the same horizon (TRaGER 1981) [other "Cantera de Margas" or "Cantera Egibil", of the elements of the assemblage includes Inoceramus Cementos Portland S. A. is located on the north frechi FLEGEL, 1. kleini MULLER and 1. percosta ern edge of the Sierra de Urbasa, south of tus MULLER (TRaGER 1989)]. In Central Europe 01azagutia (Text-fig. 28). the FAD of volviceramids coincides with that of KANNENBERG (1985) gave the first detailed Gauthiericeras margae (see TRaGER 1981, measurement of the succession (Text-fig. 28B) 1989). The occurrence of volviceramids in north and reported the stratigraphically lowest ern Spain has recently become known, whereas Cladoceramus undulatoplicatus from a level 1.0 the Platyceramus mantelli group is widely dis m below his fossil horizon LA3. This is a com tributed in this region. The first record of paratively narrow stratigraphical interval with a Volviceramus cf. koeneni from Zuazu is thus of first acme-occurrence of the index-species, here particular biostratigraphical importance, since its named the undulatoplicatus I Event. Recently, occurrence there is coincident with a Platy four levels of inoceramid concentrations over a ceramus cf. mantelli-acme. maximum interval of 1.3 m have been distin guished within this horizon (GALLEMI & al. 1997, Middle/Upper Coniacian boundary PONS & al. in prep.). The lowest record of Cl. undulatoplicatus has now been proved 5.5 m The basal boundary marker of the Upper below the undulatoplicatus level 4 of PONS & al. Coniacian proposed on a preliminary bases at the (in prep). Cl. undulatoplicatus level 4 is Brussels Symposium (KAUFMANN & al. 1996), assumed to correspond to the top of the undu i.e. Magadiceramus subquadratus (SCHUlTER), is latoplicatus I Event. lacking in the eastern Barranca, while scarce occurrences are quoted from the western Barranca Lower/Middle Santonian boundary (see LOPEZ 1996, GALLEMI & al. 1997). Its distri bution seems to be facies-dependent, occurring The extinction of Cladoceramus undulatopli mostly in marls or silty marls. However, it is also catus was suggested as a possible datum for the possible that its absence in the eastern Barranca is base of the Middle Santonian (LAMOLDA & due to the hiatus, spanning the upper Upper HANCOCK 1996). Coniacian and lower Lower Santonian. At Olazagutia, this datum is uncertain and con Consequently, the base of the Upper Coniacian in troversial (see KANNENBERG 1985, GALLEMI & al. the Barranca is defined at the first occurrence of 1997) because the range of Cl. undulatoplicatus an ammonite assemblage, dominated by has not been worked out in detail. In this paper, Protexanites bourgeoisi (D'ORBIGNY)(Text-fig. the local FAD of Texanites of the quinqueno 22). Compared with France, the more or less dosus-gallicus ,5roup is proposed as a provision simultaneous first appearance of Protexanites al marker for this boundary in the Barranca sec bontanti (DE GROSSOUVRE) at that level may indi tions. As in the French Corbieres (KENNEDY & cate the presence of the Paratexanites ser al. 1995) Texanites first occurs far above the ratomarginatus Zone sensu KENNEDY (1984a). total range of Cl. undulatoplicatus. Today, the latter zone is placed in the Upper Coniacian (KAPLAN & KENNEDY 1994). Middle/Upper Santonian boundary Coniacian/Santonian boundary The FAD of the crinoid Uintacrinus socialis GRINNELL was suggested as a possible datum for The FAD of Cladoceramus undulatoplicatus the base of the Upper Santonian (LAMOLDA & (ROEMER) was proposed as the primary basal HANCOCK 1996). It has not yet been reported boundary marker for the Lower Santonian from northern Spain. 220 THOMAS KUCHLER In this paper, the base of the Upper Santonian and the assignment of the ammonite zones to par is provisionally defined at the FAD of ticular substages. The boundaries of the Coniacian Cordiceramus muelleri (PETRASCHECK). As substages used here are based on the proposals Cordiceramus muelleri is common both in previously given by KUCHLER & ERNST (1989), Cantabria (OPPERMANN 1996) and at Olazagutia which correspond to the proposals given by the (KANNENBERG 1985), the FAD of this species is Subcommission on Cretaceous Stratigraphy in considered as a reasonable boundary marker for Brussels 1995 (Kauffamn & al. 1996) the base of the Late Santonian in northern Spain. The subdivision of the Santonian of the In north-west Europe, the FAD of Cordiceramus Barranca by means of ammonites is based on pre muelleri (PETRAS CHECK) and its occurrence falls liminary data from the Olazagutia quarry. into the Sphenoceramus pinniformis Zone Following a still unnamed interval which com according to SEITZ (1961) or in the inoceramid prises the Upper Coniacian and Lower Santonian, Assemblage Zone 28 and Zone 29 sensu TRaGER a middle Santonian zone of Texanites quinqueno (1989), respectively. According to TRaGER dosus and an upper Santonian louaniceras his (1989), this corresponds to the Uintacrinus panicumlScalarites cingulatum Zone can be rec [socialis] Zone or Gonioteuthis westfalica ognized (Text-fig. 28B). The latter zone show granulata to G. granulata Zone, respectively. affinities to the so-called Texanites gallicus and The definitions of the base of the Upper Placenticeras paraplanul11 subzones of the Santonian at the FAD of Cordiceramus bran French Corbieres (KENNEDY & al. 1995). coifonnis (SEITZ) (LOPEZ 1992d, MARTINEZ & Placenticeras polyopsis, used as index for a al. 1996) or at the FAD of Eupachydiscus iscu broad Santonian zone in the Corbieres, is known lensis REDTENBACHER (MARTINEZ & al. 1996), from OIazagutia in amateur collections but not respectively, appear not to be appropriate, from any specimen collected in situ. because the first species is rare in Spain, and The Santonian succession of Olazagutia (Text occurs already in the Middle Santonian (TRaGER fig. 28B), 220 m in thickness, can be subdivided 1989), while the second is known already from into three inoceramid zones (KUCHLER & the Coniacian of the Barranca. OPPERMANN, in prep.). These are (in ascending order): a lower Cladoceramus undulatoplicatus Partial Range Zone (=PRZ), a middle Ammonite/Inoceramid zonation Platyceramus cycloides PRZ and an upper of the Barranca Cordiceramus muelleri PRZ. An Endocostea balti ca Zone, as recognized in Cantabria (OPPERMANN The biostratigraphical subdivision of the 1996), was not recognized at Olazagutia, albeit Coniacian in the working area is based mainly on Endocostea cf. baltica (BaHM) is known to occur ammonites, with the additional incorporation of (LAMOLDA & al. 1981). This may be, however, inoceramid data. By contrast, due to their scarci caused by the broad fossil record. ty, subdivision of the Santonian by means of ammonites is very coarse, with inoceramids giv Cremnoceramus rotundatus Interval Zone ing a better resolution (Text-fig. 25). The Coniacian ammonite succession and the The base of the zone is taken at the FAD of the composition of the assemblages shows affinities to Cremnoceramus rotundatus-erectus-deformis those of assemblages from the French type locali lineage which, in the Barranca, is established by ties in Touraine and Aquitaine (see further a single record of C. rotundatus. Its upper limit is below)(Text-figs 25, 28B). Therefore, with some taken at the entry of unequivocal Coniacian modifications, the Coniacian subdivision pro ammonites. The zone comprises a 8 m thick posed by KENNEDY (l984a, b; 1985), into interval with rare (or absent) inoceramids and Forresteria petrocoriensis, Peroniceras tridorsa ammonites and is so far recognized only in the tum, Gauthiericeras margae and Paratexanites Izurdiaga section. serratomarginatus zones, can be applied (see Text-figs 21-27). However, there are significant Forresteria petrocoriensis Zone differences between KENNEDY'S 1984-1985 scheme and that in this paper, particularly in Until recently, in terms of ammonite biostratigra respect of the positions of the substage boundaries phy, the base of the Coniacian was taken at the !1 OQ N lI> n -1 0 ;:! Corbieres area Barranca po Aquitaine,Touraine 8. po I I KENNEDY, BILOTTE & "I KENNEDY, 1984a;1985,198 KUCHLER, this paper VJ MELCHIOR 1995 po " 0 Ammonite Zones Ammonite Subzones Ammonite Assemblages Inoceramid Assemblages "53' and Zones and Zones "po 3 ~ Jouaniceras hispanicuml 3 0 ~ "" Placenticeras paraplanum Sealarites cingula tum ' Cordiceramus muelleri ;:! .~ ? ~ Placenticeras ~ ~ . po SANTONIAN ~ ~ Texanites gallicus ~ Texanites quinquenodosus 1------1 "p.. po/yopsis c:::: 3 ~ g ~ Platyceramus cycloides 0 (") ~ ~ Nowakites carezi 0 unnamed interval ______i FAD of the genus Forresteria, in particular Following KUCHLER & ERNST (1989) the P. Forresteria (Harleites) petrocoriensis (COQUAND) subtricarinatum Zone is taken here to define (BIRKELUND & al. 1984, KENNEDY 1984a). the upper Lower Coniacian. The concept of a However, although this species occurs in France Peroniceras bajuvaricum Zone, introduced by and in Westphalia/Germany, it is rare in most of the them for the middle part of the Lower rest of Europe. Furthermore, in stratigraphically Coniacian in the Barranca, is abandoned here, complete and well investigated sections, its FAD is because P. subtricarinatum appears much ear located well above the level of the Didymotis II lier in the stratigraphical record than previous Event (compare CECH 1989, KAPLAN 1986, ly suggested. KAPLAN & KENNEDY 1994) and the intervening Near Zuazu, three subunits with a distinct fau interval, since it provides no new ammonite taxa nal composition can be ,recognized within the remains uncharacterized. subtricarinatum Zone (see Text-figs 21-22). The This is also true for northern Spain, where the lowest subunit up to the top of the deformis first evidence of the F. petrocoriensis Zone was IIAnagaudryceras sp. Event is characterized by provided by a single record of Forresteria the occurrence of rare P. subtricarinatum and (Harleites) sp. from the Izurdiaga section Peroniceras sp. indet. Only just below this event, (KUCHLER & ERNST 1989). The FAD of the index peroniceratids appear more commonly and are taxon falls within an acme of Micraster ex gr. associated with ?Yezoites sp. and Anagaudry cortestudinarium occurring 8 m above the ceras sp. The hardground succession of Didymotis II Event. Besides F orresteria Villanueva de Araquil to the northwest of Zuazu (Harleites) sp., only a single specimen of (see KUCHLER & ERNST 1989, Text-Fig. 5), espe Scaphites sp. is known from the zone. cially the interval immediately above Hg3, addi Furthermore, the first unequivocal F. petro tionally yielded Forresteria cf. petrocoriensis, coriensis was found stratigraphically even high Forresteria nicklesi (DE GROSS OUVRE) , Peroni er, in the Peroniceras subtricarinatum Zone of ceras cf. bajuvaricum (REDTENBACHER), Scaphites Villanueva de Araquil. The zone is thus still very kieslingswaldensis, Tongoboryceras cf. hancocki poorly documented in the Barranca. KENNEDY, Scaphites sp. indet as well as Diplomoceras sp. Peroniceras subtricarinatum Zone Near Zuazu and Ecay (Text-figs 21-22, 24), the middle subunit is characterized by a Peroniceras The base of the zone is defined by the FAD of Scaphites association, composed of abundant S. Peroniceras subtricarinatum (D' ORBIGNY). kieslingswaldensis, rare Peroniceras subtricarina Neither in the Zuazu nor in the Izurdiaga section, tum, the first Peroniceras (Peroniceras) tridorsat can the base of the zone be precisely placed, due um (SCHLUTER)(from the not figured part of to gaps in exposure or hiati. Satrustegui section) as well as Nostoceras Near Zuazu, P. subtricarinatum first appears in (Eubostrychoceras) sp. The latter species is known the Lower Izurdiaga Formation, 24 m below the from rare single specimens from the Ecay and deformis IIAnagaudryceras sp. Event (Text-fig Satrustegui exposures. 27). It is biostratigraphic ally significant that P. In the upper" subunit (from the defonnis subtricarinatum appears simultaneously with IIAnagaudryceras sp. Event upwards, see Text Cremnoceramus deformis (MEEK) and earlier figs 21-22, 24, 27), Metatissotia ewaldi (VON than Peroniceras (Peroniceras) tridorsatum BUCH), Metatissotia sp. indet and Tissotioides (SCHLUTER). P. subtricarinatum occurs much haplophyllus (REDTENBACHER) appear. more commonly than P. tridorsatum and is, there fore, of better use for biostratigraphic zonation. Gauthiericeras margae Zone The co-occurrence of P. subtricarinatum and C. deformis has also been reported from the Liencres The base of the zone is defined at the FAD of area, Cantabria (WIESE 1997). It is also biostrati Gauthiericeras margae (SCHLUTER). In the graphically important that the FADs of Zuazu C section (Text-fig. 22), it lies 7 m below Metatissotia ewaldi (VON BUCH) in Zuazu Band the Echinocorys gravesi III Event, where the Tissotioides haplophyllus (REDTENBACHER) in zonal index is found associated with Metatissotia Ecay E (Text-fig. 24) are located in the upper part evaldi Near Zuazu, the zone reaches a thickness of the subtricarinatum Zone. of about 40 m. UPPER CRETACEOUS OF THE BARRANCA 223 The margae Zone contains a more diverse tus DUJARDIN. The equivalent Upper Coniacian, ammonite fauna than the underlying subtricari Magadiceramus subquadratus Zone, has not so natum Zone. As in France, the zone is character far been recognized in the eastern Barranca. ized by the appearance of various gauthiericer atids. G. margae is extremely rare, and so far is Texanites quinquenodosus Zone known only from three, badly preserved speci mens. Locally, it ranges up to the Tridenticeras I The base of the Zone is defined at the FAD of T Event. quinquenodosus. Compared to the Zuazu section Tridenticeras tridens (SCHLUTER) and (Text-fig. 22), where T quinquenodosus first Tridenticeras varians (SCHUlTER) appear in the occurs at the level of the second Offaster nuci middle part of the zone and range up to the fOrlnis Event and apparently above the FAD of Cl. Tridenticeras II Event. This middle part (Text undulatoplicatus, its occurrence at Olazagutia figs 23-24) is characterized by a rich (Text-fig. 28B) seems to be extremely high in the Tridenticeras-Scaphites fauna with S. kies stratigraphical record. At Olazagutia, representa lingswaldensis, Gauthiericeras? boreaui (DE tives of the T quinquenodosus-gallicus group first GROS~OUVRE), Eupachydiscus isculensis occur around the "yellow bank" (= bed 68) of (REDTENBACHER), Neocrioceras (Schlueterella) KANNENBERG (1985). The zone is represented by a cf. compressum KLINGER, Gaudryceras cf. navar scarce fauna, comprising Neocrioceras (Schlue rense WIEDMANN, Hauericeras sp. and Yezoites terella) c0111pressu111 and Glyptoxoceras souqueti cf. a'maudi (DE GROSSOUVRE). Furthermore, COLLIGNON. H}phantoceras plicatum (D'ORBIGNY), so far known only from France and Germany, is proved louaniceras hispanicumlScalarites cinguIatu111 for the first time from northern Spain. Zone Peroniceras subtricarinatul11 ranges up to the Tridenticeras II Event of the Zuazu A section The zone is defined as an assemblage zone of the (Text-fig. 23). nominate index ammonites in the Olazagutia Quarry (Text-fig. 28B). Its base should be marked Protexanites bourgeoisi Zone by the FAD of Scalarites cinguIatu111 (SCHLUTER). S. cinguIatwn is known to occur in northern Europe SANTAMARIA (1992) defined the base of the zone in the Lower Campanian (SCHLUTER 1872, at the FAD of Protexanites bourgeoisi KENNEDY & KAPLAN 1995). In northern Spain, it (D'ORBIGNY). This zone is used in northern Spain in occurs significantly earlier, in the Upper Santonian view of the rarity or complete lack of Paratexanites Cordicera111us muelleri inoceramid, or Dicarinella serratomarginatus (REDTENBACHER) (see also asymetrica foraminiferal, Zone, respectively. SANTAMARIA 1991, 1992). By faunal comparison it louaniceras hispanicul11 (WIEDMANN) occurs correlates with the lower part of the P. serrato mar already in the Middle Santonian (GISCHLER & al. ginatus Zone sensu KENNEDY(1984a). 1994) and probably ranges up into the Lower In Navarra, the base of the zone is characterized Campanian (KUCHLER, in prep.). by an acme of the zonal index Protexanites bour At Olazagutia, the lowest records of both index geoisi as well as Gauthiericeras? boreaui. species come approximately from bed 138-139 KENNEDY (J 984a) and KENNEDY & al. (1995) (level minus 14 sensu KANNENBERG 1985) (Text remarked that the first appearance of P. bourgeoisi fig. 28B). They are common around bed K167. was already in the topmost part of the underlying Above this horizon of glauconitic calciturbidites, margae Zone, where it was extremely rare. S. cinguIatu111 dominates the assemblage. However, the co-occurrence of P. bourgeois! with Glyptoxoceras sp. 1, smooth baculitids and P. serratomarginatus and Protexanites bontanti Gaudryceras mite VON HAUER also occur. A sin is, at least in France, a good indication of the ser gle find of Boehmoceras krekeleri (WEGNER), ratomarginatus Zone. P. bourgeoisi occurs very somewhat higher in the successiun, indi commonly in this interval in France. Near Zuazu cates Upper Santonian in terms of ammonite (Text-fig. 22), P. bourgeoisi occurs associated biostratigraphy. Where well dated, it occurs with P. bontanti (rare) and S. kieslingswaldensis in in the Marsupites/ granulata Zone of the boreauilbourgeoisi Event, together with Westphalia/Germany (see SCHONFELD 1985, Gauthiericeras? boreaui and Baculites incurva- KENNEDY & CHRISTENSEN 1993). 224 THOMAS KOCHLER Discussion and correlations of Coniacian haplophyllus, Scaphites meslei, Yezoites subdivisions [Otoscaphites] arnaudi (DE GROSSOUVRE) and nodose baculitids. Zonation of Coniacian type regions, France Gauthiericeras margae Zone: The base of the Ammonites are comparatively scarce in the zone is marked by the appearance of Coniacian of France. KENNEDY (1984a) sum Gauthiericeras margae and Gauthiericeras marised the lithostratigraphy and faunal succes nouelianum (D'ORBIGNY). Protexanites bour sion of four regions in France, (1) the Aquitaine, geoisi enters within the zone. Additional ele (2) a small area in the Touraine of the southern ments of the assemblage are ?G. boreaui (DE Paris Basin, (3) the surroundings of Dieulefit GROSSOUVRE), Baculites incurvatus DUJARDIN (Drome), and (4) the Beausset (Var) near and Tridenticeras sp. Marseilles. Based on historic data as well as on his new field investigations he recognized the fol Paratexanites serratomarginatus Zone: The lowing sequence of ammonite zones (in ascend base of the zone is defined by the appearance of ing order): Forresteria (Harleites) petrocorien Paratexanites serratomarginatus. Protexanites sis Zone, Peroniceras tridorsatum Zone, bourgeoisi, Protexanites bontanti, Placenti Gauthiericeras margae Zone, and Paratexanites ceras sel11iornatul11 (0' ORBIGNY), Phlycticrico serratomarginatus Zone. This zonation is based ceras trinodosus (GEINITZ) and Baculites incur on scarce material and mainly unproved historical vatus also occur. Protexanites bontanti is data and it is difficult to recognize the zonal restricted to this zone, while Protexanites bour sequence in the field (KENNEDY 1984a, p. 25). geoisi occurs relatively commonly (KENNEDY 1985). Forresteria petrocoriensis Zone: F. petrocorien sis is the first ammonite appearing in the Intra-Spanish comparison (Barranca Aquitaine. According to KENNEDY (1984a), it and Burgos region) occurs at various localities and marks the base of the Coniacian in the type region. With the excep In establishing the so-called standard zonal tion of Scaphites cf. meslei DE GROSS OUVRE [=5. scheme for northern Spain, WIEDMANN (1979b) kieslingswaldensis] no other ammonite species based his data mainly on sections investigated in was found in situ. Although extensive museum the Province of Burgos (WIEDMANN 1960, 1962, material exists from the Dordogne, apart from F. WIEDMANN & KAUFFMAN 1978)(Text-fig. 26). petrocoriensis, only single specimens of The ammonite fauna of this area is dominated in Metatissotia desmoulinsi (DE GROSSOUVRE), M. the Coniacian by the four genera Tissotioides, nodosa (HYATT) and ?M. nanclasi (DE GROSSOU Metatissotia, Hel11itissotia and Prionocyclo VRE) are known to occur. ceras. These genera, however, are extremely rare or absent in the Barranca. In the latter region, the Peroniceras tridorsatum Zone: In Aquitaine, the most common genus is Scaphites, which occurs appearance of diverse peroniceratids marks the associated with Peroniceras, Gauthiericeras and base of the tridorsatum Zone. The zonal fauna Tridenticeras. Thus, both areas differ markedly consists of Peroniceras (Peroniceras) tridorsat in their ammonite assemblages and in the abun um and other Peroniceras (Peroniceras) species dance of particular genera. These faunal differ [P. (P.) westphalicum (VON STROMBECK), P. (P.) ences, resulting from ecological or paleogeo lepeei (FALLOT), P. (P.) dravidicum (KOSSMAT), graphical factors, have hitherto hindered the cor P. (P.) subtricarinatum] with rare P. relation of the ammonite zonation of the Burgos (Zuluiceras) bajuvaricum. KENNEDY (1984, successions and those applied in France 1985) also reported ?Onitshoceras ponsianum (KENNEDY 1984a) and in the Barranca (KOCHLER (DE GROSSOUVRE), Tongoboryceras hancocki, & ERNST 1989), respectively. Placenticeras fritschi (DE GROSSOUVRE), The re-investigation of WIEDMANN'S standard Forresteria (Harleites) nicklesi, Tissotia sections by SANTAMARIA (1991, 1992) and their redtenbacheri (DE GROSSOUVRE), Metatissotia detailed description have facilitated correlations slizewiczi (DE GROSSOUVRE), Metatissotia ewal between these regions. In this context, the di, Metatissotia nodosa (HYATT), Tissotioides Barranca represents an intermediate faunal ACTA GEOLOGICA POLONICA, VOL. 48 T, KUCHLER, Fig. 26 France Navarra Burgos, Northern Spain KENNEDY, 1984a; 1985,198~ KUCHLER, this paper SANTAMARIA, 1992 WIEDMANN, 1960-78 WIEDMANN, 1979b Jouaniceras hispanicuml z Eupachydiscus isculensis < Placenticeras -< Placenticeras syrtale Placenticeras '" Scalarites cinj?ulatum ~ ~ polyopsis Z Submortoniceras cf spathi SANTONIAN t-;" Texanites quinquenodosus ...0 ...~ polyopsis --'1--- ...... ~ .;] til Texanites texanus Texanites texanus unnamed interval til~ ~ d H. lenticeratiJr!nnis p, serratomarzinatus u P aratexanites =: ? ? ? Hemitissotia sp. z • ;$ H. turzoil P. bourgeoisianus Hemitissotia, turzoi ;;;i ~ ------? "'"~ ".It u 0, o " l''j'Orres'teri,(I'?aff.'ntc'kies'f:. serratomarginatus ;J .~ z: UPPER Protexanites bourgeoisi ...... < 1 AS Protexanites bourJ;eoisi Z' < -- ...-? 0 u- U < CONIACIAN Tridenticeras varians Prionocycloceras iberiense • Gauthiericeras vallei Gauthiericeras margae z: Gauthiericeras ...."'" AS ~> =: - ~ ------_ .. 0 ~ -- _. _------_ .. ------*- ~ U Gauthiericeras margae "'"~ margae ;::;- Gauthiericeras margae ;J ~ AS CO-III ------Metatissotia ewaldil d -- Reymentoceras hispanicum Barroisiceras haberfellneri 0 MIDDLE T. haplophyllus Metatissofia ewaldi u u Peroniceras :z ______e...s______~ Tissotioides haplophyllus Tissotia ewaldi .j -< ------CONIACIAN tridorsatum U Peroniceras subtricarinatum -< :z AS Subzone sensu SANr AMARIA -- -0 * u LOWER Forresteria • endemic index ammonite ~ Forresteria petrocoriensis CONIACIAN petrocoriensis AS Assemblages ....o AS -- J. (er.) rotundatus Biostratigraphical correlation between France and northern Spain and comparison of the ammonite zonations or ammonite associations (AS) between the Barranca and the Burgos area UPPER CRETACEOUS OF THE BARRANCA 225 assemblage between those of France and the This assemblage falls stratigraphically into the mostly endemic one of the Burgos region. This upper part of the Peroniceras subtricarinatum permits an interbasinal comparison and correla Zone or P. tridorsatum Zone of KENNEDY tion of the ammonite zonations between the (19 84a), respecti vel y. That means, as already above mentioned areas. A tentative correlation suggested by KENNEDY (1985) and KOCHLER & diagram is presented here in Text-fig. 26. ERNST (1989), that the Zone CO-II with T. haplo For the Barranca a modified version of the phyllus of WIEDMANN (1979b) does not represent French zonal scheme of Kennedy (1984a) was the basal unit of the Coniacian in northern Spain. applied (see Text-fig. 25). The Forresteria petro Moreover, the greater part of the Lower coriensis Zone has so far been documented in the Coniacian in the Burgos region, i.e. the F. petro Barranca by single records of Forresteria coriensis Zone as well as the lower part of the P. (Harleites) sp. indet and Scaphites sp. indet. This subtricarinatum Zone, is missing. In the is succeeded by an upper Lower Coniacian Barranca, the Lower Coniacian succession is Peroniceras subtricarinatum Zone (correspond more complete. ing to the French P. tridorsatum Zone), compris Based on the Burgos region, SANTAMARIA ing a lower subtricarinatum and a higher (1992) defined a second ammonite zone at the Metatissotia ewaldilTissotoides haplophyllus FAD of the endemic species Prionocycloceras assemblage, a Middle Coniacian Gauthiericeras iberiense (BASSE). However, as he includes in margae Zone, comprising a lower margae amd a the zone a 5 m interval below the FAD of the higher Tridenticeras varians assemblage; and an zonal index, that was characterized almost exclu Upper Coniacian Protexanites bourgeoisi Zone sively by G. margae, this zonal scheme is inher (corresponding in part to the French Paratexanites ently illogical. He interpreted this interval as a serratomarginatus Zone) comprising a sole bour subzone of G. margae, within the iberiense Zone geoisi assemblage. and suggested that the iberiense Zone corre For the Burgos area SANTAMARIA (1991,1992), sponds to the base of WIEDMANN'S Zone CO-III contrary to WIEDMANN (1979b), used the follow (=Gauthiericeras vallez' or G. margae Zone, ing zonation: respectively). P. iberiense is accompanied by Prionocycloceras turzoi (KARRENBERG) in the (iv) Hemitissotia sp. Zone upper part of this zone (Text-fig. 26). (iii) Protexanites bourgeoisi Zone (with an This fauna also shows similarities to that of included Forresteria? aff. nicklesi marker the G. margae Zone of the Barranca, which is horizon, the so-called Forresteria? aff. nick characterized by two ammonite assemblages, a lesi Subzone) lower G. margae Assemblage, with rare occur (ii) Prionocycloceras iberiense Zone (with a rences of the index-taxon, and a higher Gauthiericeras margae Subzone in the basal Tridenticeras varians Assemblage, dominated part) by Scaphites spp. and Tridenticeras spp. (i) Metatissotia ewaldi Zone Although the ammonite genus Priono cycloceras has not been recognized in the The ammonite succession in the Burgos area Barranca, the first occurrence of Tridenticeras starts with a Metatissotia ewaldi-Tissotioides spp. permits a comparison with the Burgos area. haplophyllus Assemblage, with subordinate per Tridenticeras tridens first occurs in the upper oniceratids and rare Tissotioides hispanicus part of the iberiense Zone of SANTAMARIA WIEDMANN. The M. ewaldi Zone of SANTAMARIA (1992), i.e. at a level that can be inferred to cor (1991, 1992) (approximating to WIEDMANN'S relate with that of the Tridenticeras assemblage zones CO-I and CO-II), comprises an interval in the Barranca. This species was first described between the FAD of the index species and that of by WIEDMANN (1962), from the same Burgos G. margae. It agrees very well with the strati section, although he reported it from his strati graphical position of the M. ewaldiiT. haplophyl graphically obviously higher Hemitissotia tur Ius Assemblage in the Barranca. Compared with zoi Zone (CO-IV), thereby giving the species a the Burgos region, where SANTAMARIA quoted 25 longer range. specimens of M. ewaldi alone and 30 specimens The first occurrences of T. tridens and T. varians of T. haplophyllus, both forms are extremely rare in northern Spain also permit correlation with their in the Barranca. first occurrences in Westphalia, NW Germany 226 THOMAS KOCHLER (KAPLAN & KENNEDY 1994). As in northern Spain, EVENTS; REGIONAL AND INTER both species appear in the upper part of the mar -REGIONAL CORRELATION gae Zone and range into the serratomarginatus (=bourgeoisi) Zone. However, discrepancies are Didymotis II-Event encountered in trying to correlate the first appear ances of Tridenticeras to France, since KENNEDY The Didymotis Event of the Barranca is & al. (1995) record T. varians there from as low as inferred to represent an equivalent of the the upper tridorsatum Zone. Didymotis II Event sensu ERNST & al. (1983), The succeeding interval, both in the Barranca which characterizes the Turonian/Coniacian as well as in the Burgos region, is characterized boundary interval. The event is recorded from a by the abundance of protexanitids, mainly single locality (lzurdiaga), where it is combined Protexanites bourgeoisi. In agreement with with a marked facies change from predominantly SANTAMARIA (1992), this interval should be calcareous marls to shallow marine carbonates referred to as the P. bourgeoisi Zone. The first with high siliciclastic and glauconite content. and more or less simultaneous appearance of Faunistically, it is documented by an acme-occur Protexanites bontanti at this level, by compari rence of various bivalves, in particular son with the French Coniacian, may indicate the Spondylus, and it is restricted to an interval of presence of the Paratexanites serratomargina only a few centimetres. This poor bivalve fauna tus Zone sensu KENNEDY (1984a). contains Cremnoceramus waltersdorfensis and For the Upper Coniacian of the Burgos rare Didymotis, typical of the Didymotis II Event region, SANTAMARIA (1992) introduced a elsewhere. C. rotundatus appears only a few cm Hemitissotia sp. Zone, with its base marked by higher. the FAD of Hemitissotia turzoi KARRENBERG. In Germany (ERNST & al. 1983) and the Czech This zone clearly equates with the H. turzoi Republic (CECH 1989) this event is situated some Zone of WIEDMANN (1979b). According to distance above another Didymotis-acme in the SANTAMARIA (1991), differences in the defini Upper Turonian, the so-called Didymotis I Event. tion of the zonal boundaries justified the erec In Cantabria, northern Spain, both events were tion of this new zone. However, as he never reported from exposures around Liencres defined or discussed the base of his Hemitis (KOCHLER & ERNST 1989, WILMSEN & al. 1996, sotia sp. Zone, the H. turzoi Zone of WIESE 1997) as well as from other localities in WIEDMANN (1979b) should be maintained. The northern Cantabria (WIESE 1997). As reported by virtually exclusive occurrence of the endemic KOCHLER & ERNST (1989), the Didymotis II zonal index, associated with the endemic Event at Liencres lies about 24 m above the Hemitissotia dullai (KARRENBERG), and their lower Didymotis I Event and contains an inoce abundance, characterize the sections investigat ramid fauna with C. waltersdorfensis, C. rotun ed by SANTAMARIA (1992). The Hemitissotia datus, and Inoceramus ernsti HEINZ together sp. Zone embraces, according to SANTAMARIA with Micraster leskei (DESMOULINS) and (1991), the zones CO-IV and CO-V Micraster of the praecursor-normanniae (Hemitissotia lenticeratiformis Zone) sensu cortestudinarium lineage. WIEDMANN (Text-fig. 26). At the moment, there is no direct correlation of the H. turzoi Zone to Micraster ex gr. cortestudinariwn Acme the Barranca and it may well be possible that this zone, or the upper part of the serratomar A distinct acme of Micraster ex gr. cortestudi ginatus Zone, respectively, fall within a hiatus narium occurs in the lower part of the Lower near Zuazu. Near Olazagutia on the other hand, Coniacian. In the Izurdiaga section, it begins the succession seems to be continuous, because about 6 m above the Didymotis II Event, in the WIEDMANN (1979a, p. 180) reported H. turzoi boundary interval between the rotundatus and and LOPEZ (1996) the Upper Coniacian inoce the petrocoriensis zones (beds Izl-109), and ramid zonal index Magadiceramus subquadra extends up to the top of bed IzI -114, 25 m above tus subquadratus from the base of the (see Text-fig. 27). The mass-occurrence of Olazagutia Quarry. Unfortunately, these records Micraster ex gr. cortestudinarium corresponds relate to loose material, which cannot be placed to the Micraster-acme found above the stratigraphically. Didymotis II Event at Liencres, Cantabria ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, Fig. 27 w~<------ca8 km ------~> E Izurdiaga +--- l.3km :> ~ 1.2 Jan -» ® ~ 2.8km ---~ Zuazu @ m Sarasate Formation Sarasate I 280 ®. S. "ipp~c:.epis 11. 260 ',", HgSaI -.-.vr;:t~.r;::~;'I-... ~.t~\ r 240 ~- 2km 220 200 EcayE Ammonite zones IInoceramid assemblages ® .1Jl:t,l' 180 ZF SF ..: I Texenites H ?UIl.F T. qllillqllenodosus ; quinquenodosus Mr fault Ofj'aster nuciformis 160 ULSE 140 Offaster nuciformis ~ 110 ·;T···:;:6... ····_- .. _...... _...... _...... boreaui/bourgeoisi fault Pl. cf. mant.W .j'y,,'\t.YJtL 120 fault 8 1. cf. perca.tatus Tridenticeras II 90 Gauthiericeras ICr. sp. aff. inconstans margae V. cf. koeneni Platyceramus? Tridenticeras I 100 i E. gravesi ill 70 MembaC-D Arardi CD E. gravest II Cr. d.form is ;:;;::';~s int·~~ .... :: .. :::·:··I;~·;#!W4~~:;;;::~::~:::~:~~~:~::: :-=If:ft~~=~ z Cr, crassus wr""ud;na'iumji;;~;:;~~;:;~; ~ :s 0% Cremnoceramus rotundatus l 1 105 .!.: ..~ " ..'! .. ~. DldYlfwl1J n Cr. walr.rsdotj"ensis ~ 10 Cremnoceramus Peroniceras norllf.--torfesl. __ ..... _... "...... _.. ",..._,._ ... ~ waltersdoifensiS fault .. _'-.? ...... __ ...... •...... ? ...... ",.. ",.",.. LUTE hannovrensis deverianumlrhodanicum S."-~.E!:'.~'!?!'75i~.s ~p!!!~!. ~ ~ subtricarinatum graves ilinteger m M. striatoconcentricus el marls ~ hiatus concretions fault -10 SF Sarasate Formation rt\ ..~~1 silty marls, glauconitic fVVV hiatus 9 deformislAnagaudryc.ras -20 _··········"[,······--·'T ..... _-..... j LUTE Lower Upper Turonian Event fault c::::: limestone unit UILF Upper Izurdiaga Limestone Formation 'f 'f -30 !LCE Intra Lower Coniacian Event ZF Zuazu Fonnation ~ limestone/calcareous marl LILF Lower Izurdiaga Limestone Fonnation P. subtricari"atum -40 alternation ULSE Upper Lower Santonian Event ··--·f········f········· j• .:.:~ •• ".! limestone, glauconitic gap in exposure -50 facies boundary rrrrm ? calcareous marl fault -60 line of event correlation ~ Event L-..l...... _.. _... _ ..... _ TKU96198 Event stratigraphical correlation within the Coniacian to Santonian of the eastern Barranca; the traverse from Zuazu to Sarasate shows strong facies differences, decreasing thicknesses and increasing hiati towards the east, indicating a paleo-high between Urrizola and Sarasate; for location of exposures see Text-fig. 28a ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, Fig. 27 w..«------ca8 km Izurdiaga ..(---- 1.3 km > -<- 1.2 km ~ 0 ..«'---- 2.8km --~ Zuazu @ m Sarasate Formation Sarasate I 280 ® 260 240 -<------2 km W 220 170 200 EcayE 150 Ammonite zones Inoceramid assemblages CD SF ;;j Texanites 130 7UILF T. quinqllelfodoslls 97 ::E quinquenodosus Ojfaster nucif9rmis 140 Offaster nuclformis .;. ·····:;::i'S········- ... _...... _...... _...... 110 boreauilbourgeoisi fault Pl. cf. mantelli 01· ..·" .. · .... '1-120 rault 8 I. cf. percostatus Tridenticeras IT 90 Geuthiericeras Cr. sp. aff. inconstans margae II: cf. koeneni Platyceramus? Tridenticeras I 100 E. graves; III 70 MemberC-D Arardi CD E. graves; II Cardiotaxis integer Cr. deformis deformis II Cr. crassus fault. Peroniceres CremnoceramU3 waltersdoifensis rault :~9~f::~~~L.J 10$ LUTE hannovrensis dever;anumlrhodanicum Bed E $ subtricarinetum gravesilinteger M. striatoconcentricus marls ~ hiatus concretions fault ·10 SF Sarasate Formation tlt~;;zl silty marls, glauconitic fV\N hiatus ·20 LUTE rault c:::::J limestone unit Lower Upper Turonian Event UILF Upper Izurdiaga Limestone Formation -30 ILCE Intra Lower Coniacian Event ZF Zuazu Formation A ~ limestone/calcareous marl L1LF Lower Izurdiaga Limestone Formation P. subtricarmatum l alternation ULSE Upper Lower Santonian Event I·~... ·~ .. ·"·I limestone, glauconitic gap in exposure -50 facies boundary ? fault ·60 calcareous marl line of event correlation Event mult TKU96198 Event stratigraphical correlation within the Coniacian to Santonian of the eastern Barranca; the traverse from Zuazu to Sarasate shows strong facies differences, decreasing thicknesses and increasing hiati towards the east, indicating a paleo-high between Urrizola and Sarasate; for location of exposures see Text-fig. 28a UPPER CRETACEOUS OF THE BARRANCA 227 (KUCHLER & ERNST 1989, Text-Fig. 6), the so Intra Lower Coniacian Event (ILCE) called Micraster limestone of WIESE (1997). In the Barranca, the ILCE represents a strongly Cremnoceramus deformis/Anagaudryceras sp. marked tecto-eustatic event, which is inferred to Event correspond to the so-called Ilsede Phase, origi nally distinguished in north-west Germany This event lies in the lower part of the (STILLE 1924, p. 152) and subsequently recog Peroniceras subtricarinatum Zone. In a nized throughout northern Europe (MORTIMORE sequence stratigraphical context, it is associated & POMEROL 1997, MORTIMORE & al. 1988). It is with a late highstand system tract or a sequence assumed that the Ilsede Event was a multi-phase boundary, as indicated by hardgrounds and/or event starting in the Late Turonian. The ILCE, on condensation horizons in the Barranca. The the other hand, started in the Early Coniacian event is associated with the first common occur Cremnoceramus defonnis Zone. This period is rence of Coniacian inoceramids, i.e. of marked by large hiati of variable extent and Cremnoceramus defonnis (MEEK), and particu angular unconformities at basin margins and on larly of C. waltersdorfensis hannovrensis the top of tilted, uplifted blocks, which can be (HEINZ). The essentially Turonian form observed, from Izurdiaga to Alsasua, in a E-W Mytiloides striatocol1centricus is also compara traverse through the Barranca. Turbiditic tively common. This level is recognizable in sequences, grain-flows, debris-flows and slumps many localities within the eastern Barranca were deposited in the rim synclines of the uplift (Text-fig. 27), where it is characterized either by ed structures in the Barranca and in the Vitoria an abundance maximum of Cremnoceramus Basin, Alava Province. The discontinuities are spp. and Anagaudryceras sp. or by a single mostly succeeded by the so-called Micraster Cremnoceramus layer. It probably corresponds Marls (Member C of the Zuazu Formation), to the hardground HG 3 (KUCHLER & ERNST which belong to the Peroniceras subtricarina 1989, Text-Fig. 5) within the hardground suc tum Zone. Locally, however, the hiati span a larg cession near Villanueva de Araquil northeast of er interval and the first sediments above the dis Zuazu. Just above HG 3, an association of continuity surface are then the spongiolithic, cal Cremnoceramus spp. and ammonites occurs, cm'eous marls of the Member D. similar as in the Zuazu B section. In addition to The E-W trending traverse (Text-figs 10, 27) Inoceramus ernsti and Mytiloides striatocol1- from Izurdiaga to Alsasua and the evaluation of centric us , the inoceramid fauna comprises C. the duration of the observed hiati prove the gen waltersdorfensis hannovrensis and C. deformis. eration of relief, caused by block-rotation as a The ammonite fauna is of higher diversity than result of the ILCE. at Zuazu, and is represented by Forresteria (H.) The onset of tectonic activity is indicated by cf. petrocoriensis, Forresteria (H.) nicklesi, turbidites occurring in the upper part of Member Peroniceras (Z.) cf. bajuvaricum, Tongobo B of the comparable complete succession at ryoceras cf. hancocki and Scaphites kies Zuazu (see Text-fig. 21). lingswaldensis. There is, again, a remarkable Towards the east (Text-fig. 27), the increasing dominance of Anagaudryceras sp. hiati are indicated by the progressive develop ment of erosional unconformities and/or con Echinocorys gravesilCardiotaxis integer Bed glomerates. At Urrizola, event stratigraphical correlation shows that parts of Zuazu Member D A level with Echinocorys gravesi and lie almost directly above bed UrW -61, the bed Cardiotaxis integer is found in the middle of with 0.02-0.03 m, strongly glauconitic pebbles Unit B at Zuazu (see Text-fig. 21). It lies in the which probably belongs to the lower part of middle part of the P. subtricarinatum Zone. At Member B. Compared with Zuazu, this bed Izurdiaga, this bed is missing, presumably due to reflects the absence of two lithological units, i.e. the hiatus associated with the Intra Lower the upper part of Member B and also Member C Coniacian Event (ILCE) which includes the lower (Mzcraster Marls). At Izurdiaga erosion has cut part of member (Text-fig. 27). Near Villanueva de even deeper, to the top of the Lower Izurdiaga Araquil, hardground HG 4 represents this level Limestone Formation. The conglomerate here is (see KUCHLER & ERNST 1989, Text-fig. 5). associated with amalgamation of two erosional 228 THOMAS KUCHLER 1 Arardl 2 Sarasate I 3 Izurdiaga 4 Urnzola W 5 Ecay E 6 Zuazu 7 Iturmendi ~.- ... ~------80lazagutia Sierra de Sairuslegul And i a 10km 1 s3 'Oa Urd Urdiain La Lacunca Salf SatrustegUi Ech Echarren Gu Gulina Ec Ilurmendi Ar Arbizu Arr Arruazu Ya Yilbar Zu Zuazu Ur UITIzola 01 0110 Sa Bac.aicoa li l3.:zarraga Hu Huarte Araquil VII Villanueva de Araquit Ec Ecay Iz Izurdlaga An Anaz Olazagutia brevis-humilts Event ::: :::':::::.l::::::::::':::41.::::::::.::::1~::::':::::': :::::::::::::I~:~;;e~~II! cycloidesEvent Boo muelleri Bed ?, ...... :·:: ...... tJ"R""nj'·R.' I P. eyelaides Bed eyeloides Bed I '" I.. ·.. ·· ...... · ~ ...... ~ .... ·· .... ·· .... ·.... 1...... ·· .. ·1 ...... ; 1 .. ~ ...... ~ ...... ~ ...... , ...... •· .... ·· .... •...... ·1 [undulatopUcatus IT? Event] ~ wuJulatoplicatus Event not zoned I&tfil marls thick bedded limestone! CJ marl alternation thin bedded limestonel E3 marl alternation ca1careous marl KUchler %198 Fig. 28. A. Location of the investigated Coniacian to Santonian exposures within the Barranca B. Cantera de Margas or Egibil quarry of the Cementos Portland S.A. near Olazagutia, the proposed Coniacian/Santonian boundary stratotype section; macrofossil distribution and provisional zonation; lithology simplified and modified after KANNENBERG (1985); macrofossil data after KANNENBERG (1985), LOPEZ 1990 and KOCHLER (in prep.) ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, Fig. 29 w < 26km > E Inoceramid zones Olazagutia Zuazu 1111 no record 26" brevis-humilis Event @ ... - ...... _...... _... _._._ ...... \ .. Sarasate Formation 10 188 brevis-humilis m ~Jouanieeras Event 280 Cordiceramus ~~=... K 167:::"···· II . III (turbidi~S)~.1}1ue en muelleri -10 M 150 ...... - muelleri Bed Itunnendi 260 K138 (J) -20 -30 240 ~ t -40 ~ -50 220 K68 • -60 Texaniteslcycloides II Bed -70 20{) z Inoceramid Ammonite « -80 Olazagutia Formation pomell II Transgression [:}:i}}~:}?~:l-2".g/VPP"' IZllrdiaga Limestone Formation assemblages zones Z ? 0 I- -90 Barranca Member Wernigerode ~ 180 Texanites Z Platyceramus no record « LD 1 Tectoevent ) t/) -100 quinquenodosus ~ eye/aides .. _._ .. - .... -...... _.... __ .. . __ ...... -..... _.... _...... -. ~ Offi<*' "~if_O 160 -110 FAD? Ct. undulalopltealus T"·.. ·.. ····I"i>';i"-;i',i;·;ir ? o'il«!I .. I f!1:,Il.IJ.(;.if-Ql1J.!UL. . W and ssp. ..J -120 ULSE o .' boreauilbourgeoisi 1. cf percostatus o -130 / 140 Cr. sp. aff. inconstans o I Tridenfieeras o V. of koeneni Gauthiericeras W ..J :E -140 LB 8 PI. eyeloides Bed / ,Platyeeramus ? / 170 margae o .' Tridenlieeras I 120 o -150 .' E. gravesi III i f/ / -160 150 / / 100 -170 / II Event? E. gravesi -180 yl 130 Cladoceramus I Cr. de/ormis undulatoplicatus -190 I Event__ •. ___ .1.I 110 !I Cremnoceramus -200 z / crassus « ~ -210 50 Peroniceras ",. / r. waltersdorfensis U 1 -220 9 -40 ...... _...... _... _...... _... _...... _.. _.... -.-...... - L_ ... '~ .. II ...... _..... _._ ...... _... _...... __ .~~~a-O fault Eventstratigraphical correlation within the Coniacian and Santonian of the Barranca in an E - W transect from Zuazu through Iturmendi to Olazagutia; data based partly on ZANDER (1988) (for Iturmendi), KANNENBERG (1985) and LOPEZ (1990) (for Olazagutia); for explanation of lithology see Text-fig. 27, for location of the section Text-fig. 28 UPPER CRETACEOUS OF THE BARRANCA 229 surfaces, which represent the interval from the contains Cl. undulatoplicatus michaeli (HEINZ), Sterno taxis Marls and Member B up to Member Cl. undulatoplicatus undulatoplicatus (ROMER) D (for comparison see Text-fig. 21). and Platyceramus rhomboides ssp. indet. The To the west of Zuazu, towards Olazagutia, the second Cladoceramus-acme, based on loose extent of the hiatus increases (Text-fig. 10). At specimens of Cl. undulatoplicatus, is inferred to Satrustegui and Alsasua, the Micraster Marls lie in the LB 2 level, from which LOPEZ (1990) unconformably overlie a middle Turonian hard reported Pl. cycloides ahsenensis (SEITZ). Re ground succession belonging to the investigation of the quarry and re-sampling of the Marginotruncana schneegansi Zone (Text-fig. horizon referred to the undulatoplicatus I Event 10). The Micraster Marls near Alsasua are dated shows that four levels of inoceramid concentra by Dicarinella aff. primitiva (DALBIEz) and D. tions can be distinguished over a maximum inter concavata (BROTZEN) as Lower Coniacian (lower val of 1.3 m (GALLEMI & al. 1997, PONS & al., in part of the Dicarinella concavata Zone) prep.). The lowest occurrence of Cladoceramus (ZANDER 1988). undulatoplicatus has now been proved to be 5.5 Further to the west, near Guevarra in Alava, m below the undulatoplicatus level 4 of PONS & turbidite fans (calcarenites) cut into a succession al. (in prep). Level 4 of undulatoplicatus is of basinal marls (ENGESER 1985). These tur assumed herein to correspond to the top of the bidites were part of the Ariola Fan, probably gen undulatoplicatus I Event. The second undulato erated by uplift of the nearby Aizgorri Massif, plicatus maximum of KANNENBERG (1985) has and shed in an eastern direction, into basin not been proved. inclined to the east (ENGESER 1985). WOLZ (1985) showed that the fans extend towards the Upper Lower Santonian Event (ULSE) south-east (Araya section). The fans can be cor related to Eguino in Alava and according to Near Zuazu (Text-fig. 22), this event is docu inoceramids (c. deformis, C. waltersdOljensis mented by a distinct lithological change from a hannovrensis) can be assigned to the upper nodular limestone-marl alternation to dark grey Lower Coniacian. marls with Offaster nuciformis, associated with an hiatus. If the extinction level of Cl. undulato Cladoceramus undulatoplicatus Events plicatus is taken to define the base of the Middle Santonian (see LAMOLDA & HANCOCK 1996), the The Lower Santonian C. undulatoplicatus hiatus comprises parts of Upper Coniacian ser acme can be recognized in wide parts of Europe. ratomarginatus Zone and parts of the Lower In Spain, it is known from Navarra (KANNENBERG Santonian. Compared with the Olazagutia section 1985, GALLEMI & al. 1997), Catalonia (CAUS & (Text-fig. 28B), the beds rich in Cl. undulatopli al. 1981) and Cantabria (OPPERMANN 1996, catus (LA3) sensu KANNENBERG (1985), are WILMSEN & al. 1996). As in northern Germany missing (see Text-figs 28-29).Consequently this and England (BAILEY & al. 1984), the acme com event is stratigraphically younger than the inter prises several distinct levels or peak -occurrences. val with the undulatoplicatus-acmes in the In the marginal situation of the eastern Barranca, Olazagutia Quarry. the undulatoplicatus-acme is not preserved because of an hiatus embracing virtually the Offaster nucifonnis Events entire Lower Santonian. Near Olazagutia, in the quarry of the Cementos Two event beds of Offaster nuciformis are rec Portland S.A, a continuous succession of marls ognized. They are characterized by the abun and calcareous marls crosses the dance of echinoids and occur in the more proxi Coniacian/Santonian boundary interval. Two mal sections in the eastern part of the Barranca Cladoceramus undulatoplicatus maxima ca. 19- some metres above the discontinuity surfaces of 20 m apart were recognized by KANNENBERG the ULSE (Text-fig. 22). (1985). The local FAD of Cl. undulatoplicatus The Offaster nucifonnis I Event is located ca. was reported to lie ca. 1 m below the lowermost l.5 m above the FAD of the eponymous species Cladoceramus-acme, referred to as the undu at Zuazu, and marks the first appearance of the latoplicatus I Event herein. According to genus Offaster in northern Spain. At Zuazu, the KANNENBERG (1985) and LOPEZ (1990), bed LA 3 first event is represented by a ca. 1.9 m thick 230 THOMAS KUCHLER interval with Hemiaster sp., which is common Santonien). Cretaceous Research, 6,15-32. London. er than the index taxon (PI. 13, Figs 10-12, 13- AMIOT, M. 1982. El Cretacico Superior de la Region 15). The upper nuciformis II Event, coincides Navarro-Cantabra. In: El Cretacico de Espana, pp. with the local FAD of Texanites cf. quinqueno 88-111. Ed. Univ. Complutense Madrid; Madrid. dosus. AMIOT, M., FLOQUET, M. & MATHEY, B. 1982. Aspects In Cantabria, northern Spain, Offaster nuci de la marge Ibero-Cantabrique au Turonien. Mem. formis is known to occur within the total range of Mus. Nat. Rist. Nat. Paris, (C) 49,145-158. Paris. Cl. undulatoplicatus in the Soto de la Marina AMIOT, M., FLOQUET, M. & MATHEY, B 1983. Le Domaine section (OPPERMANN 1996; KUCHLER & Navarro-Cantabre. 4d Relation entre les trois OPPERMANN, in prep.). The only other reported domaines de sedimentation du Cretace superieur. occurrences outside northern Spain are from Mem. Geol. Univ. Dzjon, 9,169-189. Dijon. GroB Biilten/Germany, i.e. from the type locality BAILEY, H. W., GALE, A. S., MORTIMORE, R. N., of Offaster nuciformis, and from England, from SWIECICKI, A. & WOOD, C. J. 1983. The Coniacian the Santonian chalk of Kent and from the Haldon Maastrichtian Stages of the United Kingdom, with residual flint gravels (ERNST 1971). Its occur particular reference to southern England. Newsl. rence in Germany is placed by ERNST & SCHULZ Stratigr., 12 (1), 29-42. Berlin-Stuttgart. (1974, p.17) in the upper Lower Santonian BENGTSON, p. 1996. The Turonian stage and substage coranguinumlwestfalica Zone. On the other boundaries. In: P. F. RAWSON, A. V. DHONDT, J. M. hand, rare Offaster sp. were found together with HANCOCK & W. J. KENNEDY (Eds), Procceedings Hemiaster sp. at Olazagutia, 14 m above the last "Second International Symposium on Cretaceous known occurrence of Cl. undulatoplicatus Stage Boundaries" Brussels 8-16 September 1995. (GALLEMI & al. 1997). Unfortunately, the total Bull. Inst. Roy. Sci. Nat. Belgique, Sciences de la range of Cl. undulatoplicatus still is uncertain at Terre, 66.Supp., 69-79. Brussels. this locality, because KANNENBERG (1985) report BIRKELUND, T., HANCOCK, J. M., HART, M. B., RAWSON, ed the species as occurring at an even higher P.F., REMANE, J., ROBASZYNSKI, F., SCHMID, F. & level (see Text-fig. 28B). Consequently, the SURL YK, F. (1984). Cretaceous Stage Boundaries - events fall either in the higher part of the Lower Proposals. Bull. Geol. Soc. Denmark, 33, 3-20. Santonian, or in the Middle Santonian. Copenhagen. BLASZKIEWICZ, A. 1980. Campanian and Maastrichtian ammonites of the Middle Vistula Valley, Poland: a REFERENCES stratigraphic-paleontologic study. Pro Inst. Geol., 92, 1-63. Warszawa. ALONSO, A. & FLOQUET, M. 1982. Sedimentation et CAUS, E., CORNELL!, A., GALLElvlI, J., GIL!, E., environnement au Turonien en Vielle Castille MARTiNEZ, R. & PONS, J.M. 1981. Field guide: (Espagne): un modele d'evolution en domaine Excursions to Coniacian-Maastrichtian of south plate-forme. Mem. Mus. Nat. Hist. Nat. Paris, (C) Central Pyrenees. WGCM Subcomm. Cretaceous 49,113-128. Paris. Stratigraphy, 3rd Working Session Tremp, March AMEDRO, F. & BADILLET, G. 1978. Repartition des 1981. Publ. Geol. Univ. Auton. Barcelona, 13,1- Ammonites dans quelques coupes du Turonien des 70. Barcelona. environs de Saumur (Maine-et Loire). C.R. Acad. CARBAYO, A., LEON, L. & VILLALOBUS, L. 1978. Mapa Sci. (Paris), 286, 323-325. Paris. geologico de Espana, 115 Gulina, 1: 50000. Mem. - & - 1982. Ammonites. In: ROBASZYNSKI (Coord.) Inst. Geol. Min. Esp., Madrid. et al. Le Turonien de la region-type: Saumurois et CECH, S. 1989. Upper Cretaceous Didymotis events Touraine. Stratigraphie, biozonations, sedimen from Bohemia. In: J. WIEDMANN (Ed.), Cretaceous tologie. Bull. Centres Rech. Explor. Prod. Elf of the Western Tethys. Proceedings 3rd Aquitaine, 6,119-225. Pau. International Cretaceous Symposium, Tiibingen AMEDRO, F., BADILLET, G. & DEVALQUE, CH. 1982. 1987, 657-676. E. Schweizerbart'sche Verlags Biostratigraphie et biozonation des ammonites du buchhandlung; Stuttgart. Turonien fran<;;ais. In: Colloque sur Ie Turonien CIRY, R. (1940). Etude geologique d'une partie des Paris 1981. Mem. Mus. Nat. Hist. Nat Paris, Sir C, provinces de Burgos, Valencia, Leon et Santander. Sciences de la Terre, 49,167-173, Paris. These, Fac. Sc. Paris et Bull. Soc. Hist. Nat. AMEDRO, F. & HANCOCK, J. M.1985. Les ammonites de Toulouse, 74, (1939), pp. 1-519. Touluse. l' autoroute 'T Aquitaine", France (Turonien et CrRY, R. & MENDIZABAL, J. 1949. Contribution it I'etude UPPER CRETACEOUS OF THE BARRANCA 231 du Cenomanien et du Turonien des confins septen ERNST, 0. & KOCHLER, T. 1992. Tecto-eustasy: Control trionaux des provinces de Burgos, d' Alava et de la of sea level movements by means of isochronous Navarra occidentale. Ann. Hebert et Haug, livre tecto-events, exemplified by Upper Cretaceous jubilaire Charles Jacob, 7,61-79. Paris. basin analyses of N-Germany and N-Spain. CNRS COBBAN, W. A. 1983. Mid-Cretaceous (Turonian) IFP intern. Symp. on Mesozoic and Cenozoic ammonite fauna from Frence Lake area of west Sequence Stratigraphy of European Basins, Dijon central New Mexico. New Mexico Bureau of Mines 1992, Abstracts, p. 2. Dijon. and Mineral Resources Mem., 41, 5-50. Socorro. ERNST, G., KOCHLER, T. & WOOD, C. J. 1992. Applied COBBAN, W. A. & HOOK S. C. 1980. Collignoniceras event and sequence stratigraphy: a north-south and woollgari woollgari (MANTELL) ammonite fauna east-west correlation of the Upper Cretaceous from Upper Cretaceous Western Interior, United between northern Germany, England and northern States. Mem. Inst. Min. Technol. New Mex., 37, 1-5l. Spain. Abstracts. 4th International Cretaceous COSCULLUELA SOLANILLA, A. 1986. Estudio micropale Symposium, p. 3. Hamburg. ontologico por medio de foraminiferos de los ERNST, G., SCHMID, F. & SEIBERTZ, E. 1983. Event materiales del Cretacico superior del sector de La Stratigraphie im Cenoman und Turon von NW Barranca este (Prov. Navarra), y sus implicaciones Deutschland. Zitteliana, 10, 531-554. Mtinchen. biostratigraficos. Unpubl. Diplom Thesis, Univ. ERNST, 0. & SCHULZ, M.-G. 1974. Stratigraphie und Zaragossa, 1-130. Zaragossa. Fauna des Coniac und Santon im Schreibkreide DAHMER, D. & ERNST, G. 1986. Upper Cretaceous Richtprofil von Lagerdorf (Holstein). Mitt. Geol. event-stratigraphy in Europe. In: O. WALLISER PalCiont.Inst. Univ. Hamburg, 43, 5-60. Hamburg. (Ed.). Global bio-events. Lecture Notes in Earth EWERT, F.-K. 1964. Geologie des Stidteiles der Sciences, 8, 353-362. Berlin-Heidelberg. Baskischen Pyrenaen. Ph.D. Westfalische DAHMER, D., ERNST, G., HILBRECHT, H. & KAPLAN, U. Landesuniv. Munster, 1-225. Mtinster. 1986. Neue Ergebnisse zur Multistratigraphie, FEUILLEE, P. 1966. Contribution it la conaissance du Sedimentologie und Palokologie der Oberkreide Cretace moyen du Nord et de lyOuest de la Navarre von Niedersachsen und Westfalen unter besonder Espagnole. Actes 4e Congr. Intern. Et. Pyren. Pau er Berticksichtigung des Cenoman bis Coniac. (1962),49-59. Pau. Gelandetagung: "Ober-Kreide NW-Deutschland" 1967. Le Cenomanien des Pyrennees Basques aux der Subkomission fUr Kreide-Stratigraphie, 4.-8. Asturies. Essai d'analyse stratigraphique. Mem. Oktober 1986, Exkursionsfiihrer. Soc. Geol. France, 108, 1-343. Paris. DEGENHARDT, T. 1983. Zur Geologie und Stratigraphie FLO QUET , M. 1983. La plate-forme nord-castillane et les der Barranca des Rio Araquil bei Irurzun (N facies proximaux. Mem. Geol. Univ. Dijon, 9,141- Spanien) unter besonderer Berticksichtigung der 168. Dijon. Ober-Kreide. Unpubl. Diplom Thesis, Freie Univ. FOURAY, M. ·1981. L'evolution des Micraster Berlin, 1-95. Berlin. (Echinides, Spatangoides) dans Ie Turonien ENGESER, T. 1985. Sedimentologische, fazielle und tek Coniacian de Picardie occidentale (Somme), tonische Untersuchungen in der Oberkreide des interit biostratigraphique. Ann. Paliontol. Basko-Kantabrischen Beckens (N ordspanien). (Invert.), 67 (2), 81-134. Paris. Ph.D. Eberhard-Karls Univ. Tiibingen, 1-232. GALLEMI, J., KUECHLER, T., LAMOLDA, M., LOPEZ, G., Ttibingen. MARTINEZ, R., MUNOZ, J., PONS, J. M. & SOLER, M. ENGESER, T., REITNER, J., SCHWENTKE, W. & 1997. The Coniacian-Santonian boundary in WIEDMANN, J. 1984. Die kretazisch-alttertiare Northern Spain: the Olazagutia section. Mineralia Tektogenese des Basko-Kantabrischen Beckens Slovaca, 9, p. 311. Bratislava. (Nordspanien). Z. Dt. Geol. Ges., 135 (1), 243- GISCHLER, E., GRAFE, K.-u. & WIEDMANN, J. 1994. The 268. Berlin. Upper Cretaceous Lacazine Limestone in the EINSELE, 0. 1993. Marine depositional events con Basco-Cantabrian and Iberian Basins of Northern trolled by sediment supply and sea-level changes. Spain: Cold-water grain associations III warm Geol. Rundschau, 82, 173-184. Stuttgart. water enviroments. Facies, 30, 209-246. ERNST, 0. 1971. Biometrische Untersuchungen tiber die Erlangen. Ontogenie und Phylogenie der OffasterlGaleola GRAFE, K.-u. & WIEDMANN, J. 1993. Sequence stratig- Stammesreihe (Echin.) aus del' nordwesteuropais raphy in the Upper Cretaceous of the Basco chen Oberkreide. N. Jb. Geol. Palaont. Abh., 139 Cantabrian Basin northern Spain. Geol. (2),169-225. Stuttgart. Rundschau, 82, 327-361. Stuttgart. 232 THOMAS KUCHLER - 1994. Sequence Stratigraphy in the Cretaceous and 1988. Die Ammoniten-Subfamilie Collignonicera Paleogene (Aptian to Eocene) of the Basco tinae WRIGHT & WRIGHT 1951 aus dem Turon Cantabrian Basin (N. Spain). Tiibinger Geowiss. (Ober-Kreide) von Westfalen und Niedersachsen Arb., A18, 1-418. Tubingen. (NW-Deutschland). Geol. PaWont. Westf., 12, 5- GROSSOUVRE, A. DE. 1889. Sur Ie terrain cretace dans Ie 45. Munster. Sud-Ouest du bassin de Paris. Bull. Soc. Giol. 1991. Zur Stratigraphie der tiefen Oberkreide im France, 3 (17),475-525. Paris. Teutoburger Wald (NW-Deutschland). Ber. HANCOCK, 1 M. 1989. Sea-level changes in the British Naturwiss. Verein Bielefeld u. Umgebung, 32, region during Late Cretaceous. Proc. Geol. Ass., 125-159. 100 (4), 565-94. London. KAPLAN, U, KELLER, S. & WIEDMANN, J. 1984. - 1991. Ammonite scales for the Cretaceous system. Ammoniten- und Inoceramen-Gliederung des Cretaceous Research, 12, 259-291. London. norddeutschen Cenoman. Schriftenreihe der HANCOCK, J. M., KENNEDY, W. J. & WRIGHT, C. W. Erdwissenschaftlichen Kommission, 7, 307-347. 1977. Towards a correlation of the Turonian Wien. sequences of Japan with those of north-west KAPLAN, U & KENNEDY, 1 W. 1994. Ammoniten des Europe. Spec. Pap. Palaeont. Soc. lapan, 21,151- westfiilischen Coniac. Geol. Pa/Ciont. Westf., 31, 168. Tokyo. 1-155. Munster. HAQ, B. U, HARDENBOHL, J. & VAIL, P. 1987. KAUFFMAN, E. G. 1986. High-resolution event stratigra Chronology of fluctuating sea levels since phy: Regional and global Cretaceous bio-events. the Triassic. Science, 235 (2), 1156-1167. In: O. WALLISER (Ed.), Global bio-events. Lecture Washington. Notes in Earth Sciences, 8, 279-335. Stuttgart. HARRIES, P. & KAUFFMAN, E. G. 1992. Evolutionary KAUFFMAN, E. G., KENNEDY W.1 & WOOD, c. 1 1996. trends in the Inoceramidae across the Cenomanian The Coniacian stage and substage boundaries. In: Turonian boundary, Western Interior Basin, USA. P. F. RAWSON, A. V. DHONDT, J. M. HANCOCK W. J. 4th International Cretaceous Symposium & KENNEDY, W. 1 (Eds) , Procceedings "Second Hamburg, Abstracts, p. 1. Hamburg. International Symposium on Cretaceous Stage HARRIES, P. J., KAUFFMAN, E. G. (Redactors) & al. Boundaries" Brussels 8-16 September 1995. Bull. 1996. Lower Turonian Euramerican Inoceramidae: Inst. Roy. Sci. Nat. Belgique, Sciences de la Terre, a morphologic, taxonomic, and biostratigraphic 66-Supp., pp. 81-94. Brussels. overview. In: C. SPAETH (Ed.). Proceedings of the KELLER, S. 1982. Die Sack-Mulde bei Alfeld (Cenoman 4th International Cretaceous Symposium, Unter-Coniac). Lithologie, Biostratigraphie und Hamburg 1992 (J ost WIEDMANN Memorial Inoceramen. Geol. lb., A64, 3-171. Hannover. Volume). Mitt. Geol.-PalCiont. Inst. Univ. KENNEDY, W. 1 1984a. Systematic palaeontology and Hamburg, 77,641-671. Hamburg. stratigraphic distribution of the ammonite faunas HILBRECHT, H. & DAHMER, D.-D. 1994. Sediment of the French Coniacian. Spec. Pap. Pa/aeont., 31, dynamics during the Cenomanian-Turonian 1-160. London. (Cretaceous) Oceanic Anoxic Event in northwest - 1984b. Ammonite faunas and the "standard zones" ern Germany. Fazies, 30, 63-84. Erlangen. of the Cenomanian to Maastrichtian Stages in their HORNER, F. & WIESE, F. 1997. Stratigraphy of a type areas, with some proposals for the definition Middle/Upper Turonian succession at the abandoned of the stage boundaries by ammonites. Bull. Geol. Hoppenstedt limestone quan'y (northern Germany) Soc. Denmark, 33, 147-161. Copenhagen. and its con'elation to adjacent areas. Freiberger 1985. Integrated macrobiostratigraphy of the Albian Forschungshefte (C), 468,171-192. Freiberg. to basal Santonian. In: R. A. REYMENT & P. KANNENBERG, M. 1985. Stratigraphische Arbeiten in BENGTSON (Eds) , Mid-Cretaceous Events: Report der Kreide der westlichen Barranca in on results obtained 1974-83 by IGCP Project no. Navarra/Nordspanien und statistische Unter 58. Publ. Paleont. Inst. Univ. Uppsala, Spec. Vol., suchungen der Echiniden-Gattung Micraster im 5,91-108. Uppsala. Steinbruch 01azagutia (Coniac-Campan). 1987. Ammonites from the Type Santonian and Unpubl. Diplom Thesis, Freie Univ. Berlin, adjacent parts of northern Aquitaine, western 1-100. Berlin. France. Palaeontology, 30 (4), 765-782. London. KAPLAN, U 1986. Ammonite stratigraphy of the KENNEDY, W. 1, AMEDRO, F. & COLLETE, c. 1986. Late Turonian of NW-Germany. Newsl. Stratigr., 17 Cenomanian and Turonian ammonites from (1),9-20. Berlin - Stuttgart. Ardennes, Aube and Yonne, eastern Paris Basin UPPER CRETACEOUS OF THE BARRANCA 233 (France). N. lb. Ceol. PalCiont. Abh., 172 (2),193- International Cretaceous Symposium, Tubingen 217. Stuttgart. 1987, 161-190. Schweizerbart'sche Verlagsbuch KENNEDY, W. J., BILOTTE, M. & MELCHIOR, P. 1995. handlung; Stuttgart. Ammonite faunas, biostratigraphy and sequence KOCHLER, T. & KUTz, A. 1989. Biostratigraphie des stratigraphy of the Coniacian-Santonian of the Camp an bis Unter-Maastricht der E-Barranca und Corbieres (NE Pyrenees). Bull. Centres Rech. des Urdiroz/Imiscoz-Gebietes (Navarra, N-Spanien). Explor.-Prod. Elf Aquittaine, 19 (2), 377-499. In: J. WIEDMANN (Ed.), Cretaceous of the Western Pau. Tethys. Proceedings 3rd International Cretaceous KENNEDY, W.J. & CHRISTENSEN W. K. 1993. Santonian Symposium, Tiibingen 1987, 191-213. Schweizer ammonites from the Kopingsberg-l borehole, bart'sche Verlagsbuchhandlung; Stuttgart. Sweden. Bull. geol. Soc. Denmark, 40, 149-156. KOHN, S. 1982. Zur Stratigraphie und Geologie der Copenhagen. Barranca westlich Irurzun (N -Spanien) unter KENNEDY, W. J. & COBBAN, W. A. 1991. Stratigraphy besonderer Berucksichtigung der Ober-Kreide. and interregional correlation of the Cenomanian Unpubl. Diplom Thesis, Freie Univ. Berlin, 1-85. Turonian transition in the Western Interior of the Berlin. United States near Pueblo, Colorado, a potential LAMOLDA, M. A. & HANCOCK, J. M. 1996. The boundary stratotyp for the base of the Turonian Santonian Stage and substages. In: P. F. RAWSON, stage. Newsl. Stratigr., 24 (112), 1-33. Berlin - A. V. DHONDT, J. M. HANCOCK & W. J. KENNEDY Stuttgart. (Eds), Procceedings "Second International KENNEDY, W. J. & GARRISON, R. E. 1975. Morphology Symposium on Cretaceous Stage Boundaries" and genesis of nodular chalks and hardgrounds in Brussels 8-16 September 1995. Bull. Inst. Roy. Sci. the Upper Cretaceous of southern England. Nat. Belgique, Sciences de la Terre, 66-Supp., 95- Sedimentology, 22,311-386. Oxford. 102. Brussels. KENNEDY, W. J. & KAPLAN, U. 1995. Parapuzosia LAMOLDA, M. A., LOPEZ, G. & MARTiNEZ, R. 1989. (Parapuzosia) seppenradensis (LANDOIS) und die Turonian integrated biostratigraphy in the Estella Ammonitenfauna der Dulmener Schichten, unteres Basin (Navarra, Spain). In: J. WIEDMANN (Ed.), Unter-Campan, Westfalen. Ceol. Palao11t. Westf., Cretaceous of the Western Tethys. Proceedings 3rd 33,1-127. Munster. International Cretaceous Symposium, Tiibingen KENNEDY, W. J. & WRIGHT, C. W. (1979). On 1987, 145-159. E. Schweizerbart'sche Verlagsbuch Kamerunoceras REYMENT, 1954 (Cretaceous: handlung; Stuttgart. Ammonoidea). l. Paleonl., 53 (5), 1165-1l78. Tulsa. LAMOLDA, M. A. & PERYT, D. 1995. Benthonic KENNEDY, W. J, WRIGHT, C. W. & HANCOCK, J. M. 1982. foramiaifera response to the Cenomanian Ammonite zonation and correlation of the upper Turonian Boundary Event in the Ganuza section, most Cenomanian and Turonian of southern northern Spain. Rev. Espan.ola Paleont., n.o England and the type areas of Sarthe and Touraine Homenaje al Dr. GUILLERMO COLOM, 101-118. in France. In: Colloque sur Ie Turonien Paris 1981. LAMOLDA, M. A. & PROTO-DECIMA, F. 1986. The Mem. Mus. Nat. Hist. Nat. Paris, Ser C, Sciences Turonian-Coniacian Boundary III Ollogoyen de la Terre, 49,175-181. Paris. (Basque Country); Foraminifers and Nannoplankton. KIND, H. D. 1967. Diapire und Alttertiar im Cretaceous Research, 7,63-75. London. Sudostlichen Baskenland (Nordspanien). Beih. LAMOLDA, M., RODRIGUEZ-LAZARO, L. & WIEDMANN, J. Ceol. lb., 66,127-174. Hannover. 1981. Field guide: Excursions to the Coniacian KOCHLER, T. 1983. Beitrage zur Iitho- und biostrati Maastrichtian of the Basque Cantabric Basin. graphischen Gliederung der echinidenreichen WGCM Subcomm. Cretaceous Stratigraphy, 3rd Oberkreide in der ostlichen Barranca sudostlich Working Session Tremp, March 1981. Publ. Ceol. Irurzun (N-Spanien). Mit speziellen Unter Univ. Auton. Barcelona, 14; I-53. Barcelona. suchungen des Campan in neuen Autobahn LOPEZ, G. 1990. Inocenimidos (Bivalvia) del Cretacico aufschliissen. Unpubl. Diplom Thesis, Freie Univ. Superior de la Cuenca Navarro-Cantabra y de la Berlin, 1-97. Berlin. Plataforma Nord-Castellana. Paleontologia y KOCHLER, T. & ERNST, G. 1989. Integrated Biostratigrafia. Unpubl. Ph.D. Univ. auton. Biostratigraphy of the Turonian-Coniacion transi Barcelona, 1-515. Barcelona. tion interval in northern Spain with comparison to 1992a. Paleontologia y bioestratigrafia de los NW Germany. In: J. WIEDMANN (Ed.). Cretaceous inoceramidos (Bivalvia) del Cretacico Superior de of the Western Tethys. Proceedings 3rd la Cuenca Navarro-Cantabra y de la Plataforma 234 THOMAS KUCHLER Norcastellana. Parte I: Situacion geologica de las G. 1998. Dating the phases of the Subhercynian series realizadas y estudio sistematico de los sub tectonic epoch: Late Cretaceous tectonics and generos Inoceramus SOWERBY y Cremnoceramus eustatics in the Cretaceous basin of northern Cox. Bol. Ceol. y Min., 103 (2),210-252. Germany compared with the Anglo-Paris Basin. 1992b. Paleontologia y bioestratigrafia de los Zbl. Ceol. Palfwnt. Teil I, 11112, 1349-1401. inocenimidos (Bivalvia) del Cretacico Superior de Stuttgart. la Cuenca Navarro-Cantabra y de la Plataforma OPPERMANN, K. 1996. Das Santon und Unter-Campan Norcastellana. Parte II: Estudio sistematico von Soto de la Marina (Kantabrien, Nordspanien): de los subgeneros Mytiloides BRONGNIART y Sedimentologie, Stratigraphie und Faziesentwick Magadiceramus Seitz. Bol. Ceol. y Min., 103 (3), lung. Unpubl. Diplom Thesis, Freie Univ. Berlin, 478-543. 1-93. Berlin. 1992c. Paleontologia y bioestratigrafia de los RADIG, F. 1973. Beitrage zur Kenntnis del' hoheren inoceramidos (Bivalvia) del Cretacico Superior de Oberkreide del' Baskischen Depression (Nord la Cuenca Navarro-Cantabra y de la Plataforma spanien) und ihrer Echinozoen-Fauna. Erlanger Norcastellana. Parte III: Estudio sistematico del Ceol. Abh., 94,1-68. Erlangen. subgenero Platyceramus SEITZ. Bol. CeDI. y Min., RAMIREZ, J. 1. 1987. Mapa geologico de Espana no. 114 103 (4),643-701. Alsasua, 1: 50 000. Mem. Inst. Ceol. Min. Esp. 1992d. Pa1eontologia y bioestratigrafia de los Madrid. inoceramidos (Bivalvia) del Cretacico Superior de RAMIREZ DEL POZO, J. 1971. Biostratigrafia y la Cuenca Navarro-Cantabra y de la Plataforma Microfacies del Jurasico y Cretacico del Norte de Norcastellana. Parte IV: Estudio sistematico del EspaEa (Region Cantabrica). Mem. Inst. Ceol. subgenero Cordiceramus SEITZ y Bioestratigrafia. Min. Esp., 78,1-357, Madrid. BDl. Ceol. y Min., 103 (5), 837-892. REITNER, J. & WIEDMANN, J. 1982. Die Deltaphasen del' ~ 1996. Aportaciones de los inoceramidos (Bivalvia) Unterkreide am Basko-kantabrischen Kontinental al conocimiento del Cretacico Superior del valle de rand, Nordspanien. N. Jb. Paldont. Abh., 165 (1), La Barranca, Navarra. Principe de Viana, 14115, 60-76. Stuttgart. 97-124. Pamplona. ROBASZYNSKI, F., ALCAYDE, G., AMEDRO, F., BADILLET, LOPEZ, G., KUCHLER, T. & TRaGER, K.-A. 1992. Upper G., DAMOTTE, R., FOUCHER, J. C, JARDINE, S., Campanian inoceramids from selected sections of LEGOUX, 0., MANIVIT, H., MONCIARDINI, CH. & La Barranca (Northern Spain). 4th International SORNA Y, J. (1982): L' etage Turonien dans sa Cretaceous Symposium, Hamburg 1992, Abstract region-type «De Saumur it Montrichard». Volume, p. 3. Hamburg. Biostratigraphie, sedimentologie, coupures. In: LOPEZ, G. & SANTAMARiA, R. 1992. Correlacion entre Colloque sur Ie Turonien Paris 1981. Mem. Mus. las zonas de ammonites e inoceramidos de parte de Nat. Hist. Nat Paris, Ser C, Sciences de la Terre, la cuenca Navarro-Cantabra y la plataforma 49, 15-28. Paris. Norcastellana. III Congreso Geologico de Espana ROBASZYNSKI, F., CARON, M., DUPUIS, CH., AMEDRO, F., y VIII congreso Latinoamericano de Geologia, GONZALEZ DONOSO, J.-M., LINARES, D., Actas, 1, 524-528. HARDENBOL, J., GARTNER, St., CALANDRA, F. & LOTZE, F. 1955. Salzdiapirismus im nordlichen DELOFFRE, R. 1990. A tentative integrated stratig Spanien. Z. Deutsch. Ceol. Ces., 105, 814-822. raphy in the Turonian of Central Tunisia: forma Berlin. tion, zones and sequential stratigraphy in the MARTiNEZ, R., LAMOLDA, M. A., GOROSTIDI, A., LOPEZ, Kalaat Senan area. Bull. Centres Rech. Explor. G. & SANTAMARiA, R. 1996. Bioestratigrafia Prod. Elf-Aquitaine, 14,213-384. Pau. integrada del Cretacico Superior (Cenomaniense SANTAMARiA, R. 1991. Ammonoideos del Cretacico Superior-Santoniense) de la region Vascocanta superior de la Plataforma Nord-Castellana y parte brica. Revista Espanola de Paleontologia, n° de la Cuenca Navarro-Cantabra. PaJeontologia y Extraordinario, 160-171. bioestratigrafia. Unpubl. Ph.D., Univ. Auton. MORTIMORE, R.N. & POMEROL, B. 1997. Upper Barcelona, 1-397. Barcelona. Cretaceous Stille Tectonics Phases and end ~ 1992. Los Ammonoideos del Cenomaniense superi Cretaceous Inversion in the Chalk of the Anglo or al Santoniense de la plataforma nord-castellana Paris Basin. Proc. Ceol. Assoc., 108, 231-255. y de la cuenca navarro-cantabra. Parte I: London. Bioestratigrafia y sistematica: Phylloceratina, MORTIMORE, R.N., WOOD, CJ., POMEROL, B. & ERNST, Ammonitina (Desmocerataceae y Hoplitaceae) y UPPER CRETACEOUS OF THE BARRANCA 235 Ancyloceratina. Treb. Mus. Geol. Barcelona, 2, Cretaceous of the Western Tethys. Proceedings 3rd l71-268. Barcelona. International Cretaceous Symposium, Tubingen - 1995. Los Ammonoideos del Cenomaniense superi 1987, 911-930. E. Schweizerbart'sche Verlags or al Santoniense de la plataforma nord-castellana buchhandlung; Stuttgart. y de la cuenca navarro-c{mtabra. Parte II: VOLTZ, H. 1964. Zur Geologie der Pyrenaiden im nord Sistematica: Acanthocerataceae. Trab. Mus. Geol. westlichen Navarra/Spanien. Ph.D. Westfalische Barcelona, 4,15-131. Barcelona. Landesuniv. Miinster, 1-266. Munster. SCHLANGER, S. 0., ARTHUR, M.A., JENKYNS, H.C. & WALASZCZYK, 1. 1992. Turonian trough Santonian SCHOLLE, P.A. 1987. The Cenomanian-Turonian deposits of the Central Polish Uplands; their facies Oceanic Anoxic Event. 1. Stratigraphy and distrib development, inoceramid paleontology and stratig ution of organic carbon-rich bed and the marine 813 raphy. Acta Geol. Polon., 42 (1/2), 1-122. C excursion. In: J. BROOKS & A. l FLEET (Eds) , Warszawa. Marine Petroleum Source Rocks. Geol. Soc. Spec. WALASZCZYK, 1. & TROGER K.-A. 1996. The species Publ., 26, 371-399. Tulsa. Inoceramus frechi (Bivalvia, Cretaceous); its cha SCHLUTER, C. 1871-1872, 1876. Cephalopoden der racteristics, formal status, and stratigraphical posi oberen deutschen Kreide. Palaeontographica, 21, tion. Paliiont. Z., 70 (3/4), 393-404. Stuttgart. 1-24, pIs. 1-8 (1871); 21, 25-120, pIs. 9-35 WIEDMANN, l 1960. Le Cretace superieur de l'Espagne et (1872a); 24,1-144 (121-264)+x, pis. 36-55 (1876). du Portugal et ses cephalopodes. C.R. 84e Congres Cassel. Soc. Savantes Paris et Dipartm., Dijon 1959, Sect. SCHOEFFLER, R. 1982. Les transversales basco-landais Sciences, So us-sect. Giol., 709-764, Paris. es. Bull. Cent. Rech. Explor.-Prod. Elf-Aquitaine, 1962. Ammoniten aus der Vascogotischen Kreide 6,257-263. Pau. (Nordspanien). 1, Phylloceratina, Lytoceratina. SCHONFELD, J. 1985. Zur Lithologie, Biostratigraphie Palaeontographica, A 118, 119-237. Stuttgart. und Fossilfilhrung des Ober-Santon Mergels von 1965. Le Cretace superieur de I'Espagne et du Westerwiehe (Ostwestfalen). Geol. Palaont. Portugal et ses cephalopodes. Estudios Geol., 20, Westj., 5, 7-20. Munster. 107-148. SCHULZ, M.-G., ERNST, G., ERNST, H. & SCHMID, F. 1979a. Mid Cretaceous Events Iberian Field 1984. Coniacian to Maastrichtian stage boundaries Conference 77. Guide II. Partie Itineraire in the standard section for the Upper Cretaceous geologique a travers Ie Cretace Moyen des Chaines white chalk of NW Germany (Lagerdorf - vascogotiques et celtiberiques (Espagne du Nord). Kronsmoor - Hemmoor): Definitions and propos Cuad. Geol. Ibir., 5,127-214. Madrid. als. Bull. Geol. Soc. Denmark, 33, 203-215. 1979b. Die Ammoniten der NW -deutschen, Copenhagen. Regensburger und Ostalpinen Oberkreide im SCHWENTKE, W. (1990). Upper Cretaceous tectono-sed Vergleich mit den Oberkreidefaunen des west imentary and facies evolution of the Basque lichen Mediterrangebiets. In: l WIEDMAN (Ed.), Pyrenees (Spain). Tii.binger Geowiss. Abh., A 7,1- Aspekte der Kreide Europas, ruGS, (A) 6, 335- 194. Tubingen. 350. Schweizerbart'sche Verlagsbuchhandlung; SCHWENTKE, W. & WIEDMANN, l 1985. Oberkreide Stuttgart. Entwicklung und Diapirismus im Estella-Becken WIEDMANN, l, KAPLAN, u., LEHMANN, l & (Nordspanien). Facies, 12,1-74. Erlangen. MARCINOWSKI, R. 1989. Biostratigraphy of the SEITZ, O. (1961). Die Inoceramen des Santon von Cenomanian of NW Germany. In: J. WIEDMANN Nordwestdeutschland. 1. Teil. (Die Untergattungen (Ed.), Cretaceous of the Western Tethys. Platyceramus, Cladoceramlls und Cordicera Proceedings 3rd International Cretaceous Sym mus). Beih. Geol. lb., 46,1-186. Hannover. posium, Tubingen 1987, 931-948. E. Schweizer STILLE, H. 1924. Grundfragen der vergleichenden bart'sche Verlagsbuchhandlung; Stuttgart. Tektonik, 1-443. Borntraeger; Berlin. WIEDMANN, l & KAUFFMAN, E. G. 1978. Mid TROGER, K.-A. 1981. Zu Problem en der Biostratigraphie Cretaceous biostratigraphy of Northern Spain. der Inoceramen und der Untergliederung des Ann. Mus. His!. Nat. Nice, 4, iiil-iii22. Nice. Cenomans und Turons in Mittel- und Osteuropa. WIEDMANN, l, REITNER, l, ENGESER, T. & SCHWENTKE, Newsl. Stratigr., 9 (3),139-156. Berlin-Stuttgart. W. 1983. Plattentektonik, Fazies- und 1989. Problems of Upper Cretaceous inoceramid Subsidenzgeschichte des basko-kantabrischen biostratigraphy an paleobiogeography in Europe Kontinentalrandes wahrend der Kreide und and Western Asia. In: l WIEDMANN (Ed.), Alttertiar. Zitteliana, 10,207-244. Miinchen. 236 THOMAS KOCHLER WIESE, F. 1995. Das mittelturone Romaniceras kallesi WILMSEN, M. WIESE, F. & ERNST, G. 1996. Facies devel Event im Raum Santander (Nordspanien): opment, events and sedimentation sequences in the Lithologie, Stratigraphie, laterale Veriinderung der Albian to Maastrichtian of the Santander deposi Ammonitenassoziationen und Paliiobiogeographie. tional area, northern Spain. In: C. SPAETH (Ed.). Berliner Ceowiss. Abh., E16 (Gundolf-Ernst Proceedings of the 4th International Cretaceous Festschrift), 61-77. Berlin. Symposium, Hamburg 1992 (J ost WIEDMANN 1996. Das nordkantabrischen Turon und Unter Memorial Volume). Mitt. Ceol.-Palaont. Inst. Coniac (Provinz Kantabrien, Spanien): Lithologie, Univ. Hamburg, 77, 337-367. Hamburg. Beckenentwicklung und Stratigraphie (Bio-, WOLZ, P. 1985. Lithologie und Stratigraphie der Event- und Sequenzstratigraphie). Oberkreide in der westlichen Barranca (Provinz 1997. Das Turon und Unter-Coniac im Alava; Nordspanien). Unpubl. Diplom Thesis, Nordkantabrischen Becken (Provinz Kantabrien, Freie Univ. Berlin, 1-107. Berlin. Nordspanien): Faziesentwicklung, Bio-, Event WOOD, C. 1, ERNST, G. & RASEMANN, G. 1984. The und Sequenzstratigraphie. Berliner Ceowiss. Abh. Turonian-Coniacian stage boundary in Lower E24, 1-131, Berlin. Saxony (Germany) and adjacent areas: the WIESE, F. & KOCHLER, T. 1995. Turonian substage Salzgitter-Salder Quarry as a proposed internation boundaries in northern Spain. Second international al standard section. Bull. Ceol. Soc. Denmark, 33, Symposium on Cretaceous stage boundaries, 225-238. Copenhagen. Brussels 8-16 September 1995, Abstract Volume, ZANDER, 1 1988. Die Ober-Kreide der Barranca im p. 126. Brussels. Raum Alsasua (Provinz Navarra, Nordspanien), WILMSEN, M. 1997. Das Oberalb und Cenoman im Nord aus mikropaUiontologischer Sicht. Unpubl. kantabrischen Becken (Provinz Kantabrien, Nord Diplom Thesis, Freie Univ. Berlin, 1-127. Berlin. spanien): Faziesentwicklung, Bio- und Sequenzstrati graphie. Berl. Ceowiss. Abh., E23, 1-167. Berlin. PLATES 5 - 14 If not otherwise stated all figures are in natural size; the specimen abbre viations consist of (1) section symbol (e.g. Ar -Arardi; IzI - Izurdiaga 1, SatrII - Satrustegui II, GZ - Ganuza IV (GZ), 01 - Ollogoyen, ZuC - Zuazu C ) (2) bed number and (3) number of an individual from partic ular beds (e.g. Izurdiaga II section, bed number 93, specimen 4 = IzII- 93/4). Asteriks and brackets are used for bed numbers which differ or are additional to those used by other authors in the Ganuza and Ollogoyen sections. All specimens, including those labelled with IPFU and housed previ ously in the Institute fijr PaUiontologie, Freie Universitiit Berlin, are cur rently housed in author's private collection. ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, PL. 5 Plate 5 Ammonites and inoceramids from the Lower Turonian of the Barranca/Navarra Fig. 1 - Inoceramus sp" specimen Ar-52/3; Lower Turonian, ?ganuzail nodosoides Zone; Arardi Fig. 2 - Inoceramus pictus bohemicus LEONHARD, specimen Ar- 50/1; Upper Cenomanian, geslinianum Zone; Arardi Figs 3-4 - Sciponoceras sp; Lower Turonian, ?ganuzailnodosoides Zone; Arardi 3 - specimen Ar-52/1 4 - specimen Ar-52/2 Figs 5-6 - Sciponoceras cf. bohemicum (FRITSCH); Lower Turonian, ganuzailnodosoides Zone, ganuzai Event; Arardi 5 - specimen Ar-53/1 6 - specimen Ar-53/2 Fig. 7a-b - Spathites (Jeanrogericeras) robustus (WIEDMANN), speci men IzII -68/1; Lower Turonian, ganuzailnodosoides Zone; Izurdiaga; b x 0.9 Fig. 8 - Spathites (lngridella) maladae (FALLOT), specimen IzII- 70/1; Lower Turonian, ganuzailnodosoides Zone; Izurdiaga Fig. 9 - Kamerunoceras ganuzai (WIEDMANN), specimen Ar-53b/1; Lower Turonian, ganuzailnodosoides Zone, ganuzai Event; Arardi Fig. 10 - Kamerunoceras ganuzai (WIEDMANN), specimen Ar-53a/1; Lower Turonian, ganuzailnodosoides Zone, ganuzai Event; Arardi; x 1.42 ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 5 ACTA GEOLOGICA POLONICA, VOL 48 T KUCHLER, PL 6 Plate 6 Ammonites from the Lower and Middle Turonian of the Barranca Fig. 1 - Pachydesmoceras denisonianum (STOLICZKA), specimen Ar (60/62)/1; Lower Turonian, ganuzailnodosoides Zone; Arardi Fig. 2 - Kamerunoceras turoniense (D'ORBIGNY), specimen Ar-60/2; basal mid-Turonian, base of the turoniense Zone, reveliere anus Event; Arardi, loose, probably from bed Ar-64 Fig. 3 - Kamerunoceras ganuzai (WIEDMANN); specimen Ar-68/2; Middle Turonian, turoniense Zone; Arardi Fig. 4 - Spathites (Jeanrogericeras) reveliereanus (COURTlLLER), specimen Ar-70/1; Middle Turonian, turoniense Zone, tur oniense/hercynicus Event; Arardi Fig. 5 - Mammites cf l1odosoides (SCHLUTER), specimen Ar-64/3; base of the mid-Turonian, base of the turoniense Zone, reveliere anus Event; Arardi Fig. 6 - Spathites reveliereanus (COURTlLLER), specimen Ar-64!1; Lower Turonian, ganuzailnodosoides Zone, reveliereanus Event; Arardi Fig. 7 - Cibolaites molenaari COBBAN & HOOK, specimen IzII-82/l; Middle Turonian, turoniense Zone; Izurdiaga ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, PL. 6 ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 7 Plate 7 Ammonites from the Middle Turonian of the Barranca and the Estella area/Navarra Fig. 1 - Placenticeras afL cumminsi CRAGIN, specimen IzlI -93/1;, Middle Turonian, turoniense Zone, turonienselhercynicus Event; Izurdiaga Figs 2-5 - Kamerul10ceras turoniense (D'ORBIGNY); Middle Turonian, turoniense Zone; Izurdiaga 2 - specimen IzI 46/1 3 - specimen IzlI-(93/94)/2; turonienselhercynicus Event 4 - specimen IzII-89-(7990)/2; immediately below the tur onienselhercynicLls Event 5 - loose specimen from the interval of the turonienselher cynicus Event; Izurdiaga I Fig. 6 - Nostoceras (Eubostrychoceras) afL matsumotoi COBBAN, specimen IzI-36/1; Middle Turonian, turoniense Zone; Izurdiaga Fig. 7 - Nostoceras (Eubostrychoceras) nov, sp" specimen IzII- 94/7; Middle Turonian, turoniense Zone, turonienselher cynicus Event; Izurdiaga Fig. 8 - Nostoceras (Eubostrychoceras) aff. matsumotoi COBBAN, specimen SatrI-Al/16; uppermost Lower Turonian to Middle Turonian; Satrustegui Fig. 9 - Nostoceras (Eubostrychoceras) aff. matsumotoi COBBAN, specimen GA-4(Ga-4+/1); Lower Turonian, Spathites reve liereanus Event; Ganuza I (GA) section ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 7 1a 9 48 ACTA GEOLOGICA POLONICA, VOL T KOCHLER, PL 8 Plate 8 Ammonites from Middle Turonian of the Barranca Figs 1,3 - Romaniceras ornatissimum (STOLICZKA); Middle Turonian, ornatissimum Zone; Izurdiaga I - specimen IzI -7112 3 - specimen IzI-67(4886) Fig. 2 - Romaniceras aff kallesi (ZAsVORKA), specimen Ar-78Il; Middle Turonian, kallesi Zone, kallesilornatissimum Event; Arardi Fig. 4 - Romanicems deverianum (D'ORBIGNY), specimen IzI-931l; Middle Turonian, deverianum Zone; loose below IzI-93; Izurdiaga Fig. 5 - Baculites undulatus D'ORBIGNY, specimen Ar-90a/l; Upper Turonian, neptuni Zone, deverianumlrhodanicum Event; Arardi ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 8 -.. -"!. Sa 5b ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, PL. 9 Plate 9 Ammonites from the Lower Turonian of the Estella area and the Barranca Figs 1-4,6 - Kamerunoceras ganuzai (WIEDMANN); Lower Turonian, ganuzai! nodosoides Zone; Ganuza IV (GZ) 1 - specimen GZ-6 (Ga-2ell); ganuzai Event 2 - specimen GZ-6 (Ga-2c-ell); ganuzai Event 3 - specimen GZ-7 (Ga-2gll); ganuzai Event; Fig, 3b is upside-down 4 - specimen GZ-6 (Ga-2c-e/2); ganuzai Event 6 - specimen Gz-31l; kossmati Event Fig. 5 - Placenticeras aff cUinminsi CRAGIN, specimen GZ-6 (Ga- 2e/2); Lower Turonian, ganuzailnodosoides Zone, ganuzai Event; Ganuza IV (GZ) Fig. 7 - Spathites cf, reveliereanus (COURTILLER), specimen ?GI-2 (BI-3e); Lower Turonian, ganuzailnodosoides Zone, top most part of the reveliereanus Event; Ganuza II (GI) Fig. 8 - Choffaticeras quaasi (PERON), specimen IzII-68-/2; Lower Turonian, ganuzailnodosoides Zone; Izurdiaga ACT A GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 9 4a 1a 4b 3a 7 ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, PL. 10 Plate 10 Ammonites and inoceramids from the Lower Turonian of the Barranca and Middle Turonian of the Estella area Fig. 1 - Kamerunoceras turoniense (D'ORBIGNY), specimen GA-9b (Ga-8/2); Middle Turonian, turoniense Zone, turonien se/hercynicus Event; Ganuza I (GA) Fig. 2 - RomClnicerCls kallesi (ZAZVORKA), specimen ?01-103/1; Middle Turonian, ornatissimum Zone, base of the zone TuVIII sensu WIEDtvlANN (l979a); Ollogoyen Fig. 3 - Mytiloides hercynicus (PETRASCHEK), specimen GA-9b (Ga- 8/29); Middle Turonian, turoniense Zone, turoniense/her cynicus Event; Ganuza I (GA) Fig. 4 - Mytiloides kossmati (HEINZ), specimen Ar-64 (unregistered); Lower Turonian, ganuzai/nodosoides Zone, reveliereanus Event; Arardi Fig. 5 - Spathites reveliereanus (COURTILLER), specimen GA (3/4)11; Lower Turonian, ganuzailnodosoides Zone, reve liereanus Event; loose between GA-3 and GA-4, Ganuza I (GA) Figs 6-7 - Collignoniceras vvoollgari (MANTELL); Middle Turonian, ornatissimul11 Zone; Ollogoyen 6 - specimen 01-(102/103)/1 7 - specimen 01-(102/103)/2 Fig.8-Romaniceras kallesi (ZAZVORKA), specimen GA-*llal1; Middle Turonian, kallesi Zone; Ganuza I (GA), approxi mately 120 m level ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 10 6 7 8b ACTA GEOLOGICA POLONICA. VOL. 48 T. KOCHLER. PL. 1 J Plate 11 Ammonites from the Upper Turonian of the Estella area Figs 1-2 - Subprionocyclus ex gr. neptuni-hitchinensis; Upper Turonian; Ollogoyen 1 - specimen IPFU-GE 89/4 (cf. KOCHLER & ERNST 1989, PI. 2, Fig. 1); waltersdOljensis/germari Zone, Subprionocyclus II Event; 2 - specimen IPFU-GE 89/5 (cL KOCHLER & ERNST 1989, PI. 2, Fig. 2); neptuni Zone, Subprionocyc lus I Event (= bed 0l-110+1m) Figs 3,5-6,10 - Romaniceras deverianum (D'ORBIGNY); Upper Turonian; Ollogoyen 3 - specimen 01-*811; upper part of the waltersdor fensis/germari Zone, ca. 40 m-level of the Ollogoyen section. 5 - specimen IPFU-GE 8911 (cL KOCHLER & ERNST 1989, PI. 1, Fig. 1); waltersdOljensis/germari Zone, 16,5 m- level of the Ollogoyen section 6 - specimen 01-* 111 bl1; neptuni Zone, Ollogoyen, Subpriol1ocyclus I Event 10 - specimen IPFU-GE 89/2 (cf. KOCHLER & ERNST 1989, PI. 1, Fig. 2); waltersdOljensis/germari Zone, 3 m above Subprionocyclus II Event Fig. 4 - Prionocyclus cL germari (REUSS), specimen IPFU GE 89/6 (cf. KOCHLER & ERNST 1989, PI. 2, Fig. 3); Upper Turonian, waltersdOljensis/germari Zone, 3 m above Subprionocyclus II Event at the 34 m-level of the section; Ollogoyen Fig. 7 - Scaphites geinitzii D'ORBIGNY, specimen 01-*109d/2; Upper Turonian, base of the neptuni Zone, geinitzii Bed; Ollogoyen Fig. 8 - Subprionocyclus neptuni (GEINITZ), specimen 01- *109d/1; Upper Turonian, base of neptuni Zone, geinitzii Bed; Ollogoyen Fig. 9 - Subprionocyclus ex gr. neptuni-hitchinensis, speci men 01-*I11b/2; Upper Turonian, neptuni Zone, Subprionocyclus I Event; Ollogoyen ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 11 4b 2 ACTA GEOLOGICA POLONICA, VOL 48 T, KUCHLER, PL 12 Plate 12 Ammonites from the Lower Coniacian of the Barranca Fig. 1 - Forresteria (Harleites) sp., specimen IzI-109/1; Lower Coniacian, petrocoriensis Zone; Izurdiaga Fig. 2 - Forresteria (Harleites) nicklesi (DE GROSSOUVRE), specimen IPFU-GE8917 (cf. KUCHLER & ERNST 1989, PI. 2, Fig. 4); Lower Coniacian, subtricarinatum Zone; Villanueva de Araqui1, HG3 Fig. 3 - Peroniceras (Peroniceras) tridorsatum (SCHLUTER), speci men IPFU-GE 89/9 (cf. KOCHLER & ERNST 1989, PI. 2, Fig. 6); Lower Coniacian, subtricarinatum Zone; Satrustegui I, bed A3 Fig. 4 - Peroniceras (Peroniceras) subtricarinatum (D'ORBIGNY), specimen IPFU-GE 89/11 (cf. KUCHLER & ERNST 1989, PI. 3, Fig. 1); Lower Coniacian, subtricarinatum Zone; Ecay E, bed P Fig. 5 - Peroniceras (Zuluiceras) cf. bajuvaricum (REDTENBACHER), specimen IPFU-GE 89/8 (cf. KUCHLER & ERNST 1989, PI. 2, Fig. 5); Lower Coniacian, subtricarinatum Zone; Villanueva de Araquil, 0.3 m above HG3, Figs 6-7 - Anagaudryceras sp.; Lower Coniacian, subtricarinatum Zone; Zuazu, 6 - specimen ZuB-lOOe/1 7 - specimen ZuB-lOOe!2 ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, PL. 12 ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 13 Plate 13 Ammonites and echinoids from the Lower and Middle Coniacian of the Barranca Figs 1-2 - Tissotioides haplophyllus (REDTENBACHER) EcE-(Ech. B)/l; Lower Coniacian, subtricarinatum Zone, Echino corys gravesi II Event; Ecay E, at the zero level of the sec tion Fig. 3 - Nowakites pailletteanus (D'ORBIGNY), specimen ZuC-340c/1; Middle Coniacian, margae Zone; Zuazu Figs 4-5 - Gauthiericeras margae (SCHLUTER), specimen ZuC (unregistered); Middle Coniacian, margae Zone; Zuazu Fig. 6 - Peroniceras subtricarinatum (D'ORBIGNY), specimen ZuB-(bed 100 -12m)/l; Lower Coniacian, subtricarinatum Zone; 12 m below "deform is " I1Anagaudryceras sp. Event, Zuazu Figs 7-8 - Eupachydiscus isculensis (REDTENBACHER), specimen ZuA-AZ1/1; Middle Coniacian, Gauthiericeras margae Zone, ammonite bed; Zuazu Fig. 9 - Protexanites bontanti (DE GROSSOUVRE), specimen ZuC 346/1; Upper Coniacian, bourgeoisi Zone, boreaui/bour geoisi Event; Zuazu Figs 10-15 - Offaster nucifonnis ERNST. Uppermost Lower Santonian or lowermost Middle Santonian, nucifonnis Event I; Zuazu 10-12 - specimen ZuC-364/1 13-15 - specimen ZuC-364/2 ACTA GEOLOGICA POLONICA, VOL. 48 T. KUCHLER, PL. 13 ACTA GEOLOGICA POLONICA, VOL 48 T. KOCHLER, PL 14 Plate 14 Ammonites from the Middle Coniacian to Middle Santonian of the Barranca Figs 1-3 - Protexanites bourgeoisi (D'ORBIGNY); Upper Coniacian, bourgeoisi Zone, boreaui/bourgeoisi Event; Zuazu 1 - specimen ZuC-347/349/1; loose between beds 347 and 349 2 - specimen ZuC-348/2 3 - specimen ZuC-347/2 Fig. 4 - Baculites incurvatus DUJARDIN, specimen ZuC-348/1; Upper Coniacian, bourgeoisi Zone; Zuazu Fig. 5 - Tridenticeras varians (SCHLUTER), specimen ZuC-131/1; Middle Coniacian, margae Zone, Tridenticeras I Event; Zuazu Fig. 6 - Tridenticeras tridens (SCHLUTER), specimen ZuA-B 500/1; Middle Coniacian, margae Zone; loose, probably from with in bed 204 (= bed B 500 sensu KUHN 1983); Zuazu Fig. 7 - Texanites quinquenodosus (REDTENBACHER), specimen ZuC-366/l; Middle Santonian, quinquenodosus Zone; Zuazu ACTA GEOLOGICA POLONICA, VOL. 48 T. KOCHLER, PL. 14