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Moscovian and rocks in the frame of the cyclic Permo- deposits of the Carnic Alps and related areas

Gian Battista VAI & Corrado VENTURINI Dipartimento Scienze Geologiche, Via Zamboni 67, 1-40127 Bologna (Italy)

Vai G. B. & Venturini C. 1997. — Moscovian and Artinskian rocks in the frame of the cyclic Permo-Carboniferous deposits of the Carnic Alps and related areas, in Crasquln-Soleau S. & De Wever P. (eds), Peri-Tethys: stratigraphie correlations, Geodiversitas 19 (2) : 173-186.

ABSTRACT Guidelines and legend for the Moscovian and Artinskian maps to be produ­ ced within the Peri-Tethys Programme are presented. An updated review of KEYWORDS the most important composite sections exposed in different parts of the Palaeogeographic maps, Carnic Alps and drilled in the northern Adriatic Sea is presented. The sec­ guidelines, legend, tions spanning a large part of the Mid-Late Carboniferous to terminal low and high frequency cycles, time interval are correlated so as to show the major sedimentary tectonics, cycles and the main regional trends of tectonic us eustatic sea level changes. eustatism, parasequences, High frequency cyclicity is also summarized in terms of parasequences, espe­ , cially for the Gzhelian , although the entire Pontebba Supergroup correlation, (Moscovian to Artinskian) was known for many decades as a classic cyclic Southern Alps, Adriatic Sea. sedimentation area.

RÉSUMÉ Le schéma directeur et la légende des cartes du Moscovien et de l'Artinskien qui seront réalisées dans le cadre du Programme Péri-Téthys sont proposés. MOTS CLÉS Nous présentons ici une révision des coupes composites les plus importantes cartes paléogéographiques, des Alpes Carniques et des forages du nord de la Mer Adriatique. Les coupes, directives, légende, qui s'étalent sur une grande partie du Carbonifère moyen-supérieur au cycles à faible et haute fréquence, Permien terminal, sont corrélées et montrent les principaux cycles sédimen- tectonique, taires ainsi que les modifications tectono-eustatiques majeures. Une cyclicité eustatisme, parasequences, haute fréquence est également résumée en termes de paraséquences, surtout Gzhelien, au Gzhelien, bien que le Super-Groupe de Pontebba (Moscovien-Artinskien) corrélation, soit connu depuis plusieurs décennies comme une région à sédimentation Alpes méridionales, mer Adriatique. cyclique.

GEODIVERSITAS • 1997 • 19(2) 173 Val G. B. & Venturini C.

FOREWORD new fusulinid genera Mesoschubertella, Toriyamaia, Praeskinnerella, Darvasella and by Before entering the topic of this paper, an intro­ the ammonoid genera Artinskia, Kargalites, duction is needed to provide the aim, legend, Almites, Cardiella, Paragathiceras, Aristoceratoides, and guidelines according to which the present Pseudogastrioceras. The selected late early Permian and the following stratigraphic conttibutions time has some advantages: it has a dutation (Pasini & Vai, Di Stefano & Gullo, Cassinis, almost similar to that of the Moscovian; it is clo­ Cassinis & Ronchi, Vai, Geluk, all in this volu­ sely equivalent of the Chinese Chihsian and me) have been submitted to the ad hoc working practically overlap with the Yachtash-Bolor fau- group, in view of the compilation of the palaeo- nal step of Leven (1993) comprised between the geographic maps of the Moscovian and top of and the base of Kubetgandian; Artinskian within the aims and the scope of the it minimizes the imprecision deriving from the Peri-Tethys Programme (PTP). Further contribu­ poor correlation and definition level of indivi­ tions are expected and welcome. dual stages involved.

GUIDELINES It is preferred to receive conttibutions coordina­ The conttibutions provide original and/or upda­ ted in a set of sections by country or group of ted stratigraphic rough data on the Moscovian countries (such as e.g.: France, Belgium, UK, and/ot/to Artinskian time slices in the diffetent Germany, Poland, Hungary, Austria + Tchekia, areas within the scope of the PTP, mainly as spot Bulgaria + Rumania, former Yugoslavia, Turkey, columnar sections, with the aim to act as valida­ Greece, Italy, Spain, NW Africa, Lybia, Central tion data points for the following map recons­ W Africa, Middle East + Arabia, Iran, truction: + Ukraina, , a.s.o.). However, 1. The Moscovian Map, focusing the Age inter­ submissions provided by independent indivi­ val (about 312-305 Ma) and including additio­ duals or research groups are also welcome. nal information up to the top of the The contributions consist mainly of a set of spot Catboniferous (about 296 Ma) columnar sections (stratigraphic columns), possi­ 2. The Artinskian Map, focusing the bly correlated on a stratigtaphic chart (see f.i. Artinskian + Bolotian Age interval (about Ziegler 1988), possibly accompanied by location 280-273 Ma) and including additional informa­ and/or simplified geological maps, and illustrated tion down to the base of the Permian (about by a concise explanatory text. The text shall not 296 Ma). exceed ten double-spaced typed pages (or five printed pages). Columnar sections, cotrelation The Moscovian Stage is used here as roughly charts (one or more if needed) and location/geo- logical maps must be dtawn on A4 sized sheets represented by the Aljutovella aljutovica to allowing final print reduction up to 50%. Each Fusulina cylindrica fusulinid zones, by the individual map dtawing must contain a graphic Idiognathoides marginodosus to scale. obliquus-Neognathodus roundyi zones, and by the Paralegocems to Wellerites ammonoid Columnar sections are to be dtawn and correla­ zones. ted on time/space (chronostratigraphic) dia­ grams. The thickness of the different litho- The Artinskian + Bolorian Stages are used here as stratigtaphic units will appear from separate roughly corresponding to the Chalaro- labelling in a side-column and from the text. The schwagerina solita, Pamirina, Ch. (= "Pseudo- vettical axis of the columnar sections (time) will fusulina") vulgaris, Misellina dyhrenfurthi and adopt the geological time scale shown in the next Misellina parvicostata fusulinid zones, to the heading. artinskiensis, whi- Each individual columnar section (tepresenting a tei, Neostreptognathodus pequopensis and N. leono- true spot-like section exposed in the field ot vae conodont zones, and are characterized by the drilled by a well, or a composite section whose

174 GEODIVERSITAS • 1997 • 19 (2) Cyclic Permo-Carboniferous of the Carnic Alps

TABLE 1. — PTP time scale for the Carboniferous and Permian the previous one used in Dercourt et al. (1993) Periods (ages of the lower boundary in millions ). with some integrations derived from Ziegler (1988), Sassi & Zanferrari (1990) and Vai Early Induan 251 Ma (1991). It seems particularly useful to include whenever possible in the maps the isopach Changxingian 255 Dhzulfian 259 contours or the margins of the main basins of the Midian 264 late Carboniferous (and Moscovian if available Murgabian 269 separately) and of the early Permian (plus Late Permian Kubergandian 273 Artinskian if available separately). Bolorian 275 In the present stage, the basic legend type for Artmskian 280 both the sttatigraphic columnar sections and the Sakmarian 288 related geological maps (if available) is reported Early Permian 296 in Appendixes 2 and 3 respectively. Gzhelian 301 When additional subdivisions and symbols are Late Carboniferous 305 needed, they have to be added by the contribu­

Moscovian 312 tors in their own legend sheets, preferably Middle Carboniferous 323 conforming to the use by the authors reported above. 328 Viséan 345 PTP INTERVAL TIME SCALE The numerical time scale for Carboniferous and Permian chronologic classification down to stage elements are included within the resolution level tentatively adopted fot the purposes of the power of a point on a 1:10 000 000 scale map - PTP has a simple pragmatic meaning to enable a which is about a citcle of 1 km radius) should common frame for communication among diffe­ consist of a main column and a few side-colums. rent contributors. However, as a matter of fact The main column should include lithology, the present state of chronometric calibration of lithostratigraphic units, and depositional envi­ the conventional stratigraphic scale in the time ronments. The side-columns should include data interval concerned is largely unsatisfactory as on thickness, unconformities, tectonic, magma- appears from the vety large error bars (from 3 to tic and metamofphic events, tectofacies and 9 Ma) affecting individual stage, and sys­ other additional information (see legend). The tem boundary ages (Odin 1994). Especially poor location of each section within a resolution is the knowledge about the or power of 1 km of radius should be identified by subsystem. The late Catboniferous means of its Latitude and Longitude figutes. is mainly dated from continental successions not If graphically possible, the columns should inclu­ evenly related to the marine ones. A further limi­ de the data on both the Moscovian and the tation derives from the still poor level of formally Artinskian (plus possibly the intervening inter­ defined standard chronostratigtaphic subdivi­ val) on the same sheet (also by using the long sions (GSSP) in this time interval. People invol­ side of the A4 sheet). ved are close to an agreement for the two and some subsystem boundaries but have not yet Drawings should be submitted in both color and paid any attention to the stage boundaries. black and white (BW) versions, one for the sake In such a condition, our aim was first to have a of the future map compilation, the othet for the reliable frame of reasonable duration of stages, immediate putpose of printing the volume. To regardless of precise boundary ages, and second, speed work, it is suggested to label with numbei to maintain a possible continuity with the time (see legend) the different units in the BW version scale used in the previous Tethys Program. and to fill them by hand colors for the color ver­ Therefore, the numetical scale adopted here sion. (Table 1) was based mainly on the time scale by The structure of the legend mainly confotm to

GEODIVERSITAS • 1997 • 19(2) 175 Vai G. B. & Venturini C.

Ross et al. (1994), already used in Baud et al. Carboniferous (to Permian) age sealing the (1993), as a preliminary output of the time scale Southalpine crystalline basement in the by Menning (1995). Some modifications have Lombardy lake region, Orobic, Giudicarie and been derived from Claoué-Long et al. (1995 and Alto Adige areas. Recent research on physical pers. comm.), Roberts et al. (1995) and from stratigraphy, environmental interpretation and attempts at the best fit with Harland et al. palaeoclimatic evolution has provided the basis (1990) and Odin (1994). for a better undetstanding also in terms of sequence stratigraphy and sedimentary history It is hoped that this first group of contributions (Venturini 1990, 1991; Krainer 1992). prompt other interested specialists to provide soon updated informations for those other coun­ CYCLICITY, SEQUENCES AND TRENDS IN tries which are relevant for the compilation of an THE PERMO-CARBONIFEROUS PONTEBBA accurate map reconstruction. SUPERGROUP (Figs 1-3) Local autocyclic and tectonic processes as well as over-regional cycles have been recognized in the LATE CARBONIFEROUS AND EARLY sedimentary patterns of the Pontebba PERMIAN OF THE CARNIC ALPS Supergroup. Detailed descriptions and columnar sections showing the cycles are found in recent The late Moscovian to late Artinskian (s. I.) papers (e.g. Venturini 1990, 1991; and especially Pontebba Supergroup represents a classic area for Massari et al. 1991), although cyclic sedimenta­ late Palaeozoic stratigtaphy acting as a bridge tion was also stressed by previous authors. connecting the continental Permo-Carboniferous As a whole, the Pontebba Supetgroup is viewed sequence of Western Europe and the marine one as a late Hercynian transtensional pull-apart of the Russian Platform, the Urals and Middle basin-fill, consistent with both the post tectonic East to Asia (peri-Tethyan and Tethyan tealm). telaxation of the very short emersion of the In fact, in the area including at least the Carnic Palaeocarnic Chain (Vai 1976) and the late Alps, the Karawanken, the outer Dinarides and Catboniferous-early Permian trans-Variscan the northern Adriatic Sea both facies interfinger megashear (Arthaud & Matte 1977). It forms a conspicously, providing excellent tools for eco- composite sedimentary cycle defined by the stratigraphic correlations (Kahler & Prey 1963; Hercynian (Carnic) non conformity at the base Selli 1963; Kochansky-Devidé 1965). and the mid-Permian (Saalic) disconformity at Within the frame of the eastern Southern Alps, the top. This sedimentary cycle is notably dis­ the Pontebba Supergroup (Venturini et al. 1982) tinct from the Permo-Triassic cycle and following represents a superb exposure of a post Hercynian ones by its smallet extent and different architec­ cover (episutural basin) sealing, with sharp angu­ ture in response to a different stress regime. lar unconformity, the severely thrusted The most prominent character of this Permo- Hercynian (Palaeocarnic) Chain and its shallow Carboniferous sedimentary cycle is that it is epimetamorphic equivalents of the Comelico composed by a quite regular series of cyclothems basement (Vai 1976; Castellarin & Vai 1981; Vai having a mean thickness of about 30 m. Almost & Cocozza 1986). The basal unconformity of the same type of modal cyclothem is tecognized the Pontebba Supergroup is well exposed over an in two different sedimentary environments. One, area some hundreds of square km, although it is dominated by marine carbonate deposits (Pizzul intersected by large Mesozoic extensional faults and Auernig Formations, see below), statts with and Alpine thrust faults. Such faults are widely an unconformity by which progradation and spaced from each other to enable large blocks shallow-marine coarse silicoclastic deposits rest showing the primary Hercynian basin/cover rela­ on ramp sediments; a transgressive fine-grained tionship preserved (Castellarin & Vai 1981). The highly fossiliferous clastic layer is closed by a western correlative of the Pontebba Supergroup limestone horizon followed by shallowing is represented by the continental elastics of late upward clastic sediments. The other one, domi-

176 GEODIVERSITAS • 1997 • 19(2) o UPPER CARBONIFEROUS CYCLOTHEMS (Pramoiio,CARNIC ALPS) a <

FIG. 1. — Third and fourth order lithocycles from the Carboniferous and earliest Permian of the Carnic Alps. Key: LST-TST-HST, low stand, transgressive and high stand systems tracts: MFS, maximum flooding surface; B, Bombaso Formation; the second column from left shows the stratigraphic subdivision according to the Austrian authors. Notice scale change from part 1 to part 2 of the section. See also legends in Appendixes 1, 2 and 3. Vai G. B. & Venturini C.

nated by more or less continental silicoclastics The cyclostratigraphic analysis of the Uppet (Corona and Carnizza Formations), starts with Carboniferous succession of the Pramollo Basin superimposition of fluvial conglomerates on del­ ("Auernig group" and its basal immature elastics, taic to coastal plain muddy sediments followed referred to as Bombaso Formation) deserves by fine-grained transgressive clastic ramp depo­ some additional remarks. sits and highstand fine silicoclastic marine bands. 1. The Bombaso Formation is hetetopic with It follows that the upper Carboniferous cyclo- both the Meledis Formation and the lower part thems of the Carnic Alps can be described as of the Pizzul Formation (Venturini 1990, 1991). high-frequency small-scale sequences in terms of This is an effect of the Kasimovian synsedimen- sequence stratigraphy and depositional systems. tary tectonics, resulting in the uplift of a narrow Furthermore, the alternation of either carbonate Horst exposed to erosion. It lined up with the or silicoclastic bundles suggests a climatic modu­ basin axis splitting it into two separated and lation of higher rank cyclicity in respect to that independent Graben. involved in the generation of cyclothems. 2. During late Gzhelian times the north-eastern A similar, although more irregular and less stu­ Grabe, that is the well known area of Auernig, died cyclicity, is shown in almost all remaining Carnizza and Corona Montains, was affected by late Carboniferous to early Permian Formations strong tectonic subsidence. The sedimentation except the Trogkofel Limestone (and telated tate remarkably increased as compared to the units, see below). previous Kasimovian-early Gzhelian figures Both larger and smaller-scale cycles recognized in (Ventutini 1991). the Pontebba Supergroup are closely similar to It follows that, for a correct analysis of the cyclic the classical Permo-Carboniferous cyclothems of upper Gzhelian succession, interfering of pos­ North America, the Russian Platform, Western sible tectonic pulses must be carefully discounted Europe and Africa (or to their internal subdivi­ from the effects of the glacio-eustatic oscillations. sions in formations and members). As an example, one can compare the impressive corres­ THE PERMO-CARBONIFEROUS PONTEBBA pondence between the four Gzhelian formations SUPERGROUP (Fig. 2) of the Carnic Alps (Pizzul, Corona, Auernig and For a better understanding of the palaeogeogra- Carnizza) and the corresponding four Gzhelian phic meaning of the Moscovian and Artinskian "horizons" of the Russian Platform (Ross & Ross rocks exposed in the Catnic Alps, a summary 1988: 234; Izart et al. 1995). On the other hand, about its almost continuous succession ranging similarly impressive is the almost perfect match from late Moscovian to eatly Kubetgandian (in between twenty-six cyclothems of the upper the eastern area) is useful. Gzhelian in the Carnic Alps (Fig. 1) and the The sequence starts with the fine clastic to carbo­ twenty-one units of the roughly corresponding nate mainly basinal Meledis Fotmation not Virgilian in Kansas (Ross & Ross 1988: 233). conformably overlaying the Hercynian chain. The twenty-two cycles recognized within the The Meledis Formation often rests on a thin Corona, Auernig and Carnizza Formations basal carbonate breccia body (Malinfier Horizon) (Massari et al. 1991) added to the three out of and in some areas is laterally replaced by fault- the four cycles known in the "Lower" scarp related plygenic breccias and immatute Pseudoschwagerina Formation (Homann 1969) coarse-grained siliciclastics (Pramollo Mb) altogether roughly correspond to the upper half named, as a whole, Bombaso Formation of the Gzhelian, lasting as a whole stage about (Venturini 1990). The Meledis and Bombaso 5 Ma The ratio closely approximates the magic Formations span from the late Moscovian figure of 100 ka, which is thought to be the for­ (Mjackovian) to the Kasimovian (Protriticites to cing orbital (short excentricity) factor of many Montiparus Zones). They are followed by the late depositional cycles (e.g. the glacial Kasimovian to early Gzhelian (Triticites, Jigulites climatic-controlled paired Emiliani isotope and Daixina Zones) Pizzul Formation, composed "stages"). of outer shelf limestones and pelites alternating

178 GEODIVERSITAS • 1997 • 19(2) Cyclic Permo-Carboniferous of the Carnic Alps

FIG. 2. — Lithostratigraphic subdivision of the Upper Carboniferous of the Carnic Alps. Key: AU, Auernig Fm; B, Bombaso Formation; Cor, ; PS. INF., "Lower Pseudoschwagerina" Formation; V.D., Val Dolce Formation; the fifth column from left shows the stratigraphie subdivision according to the Austrian authors. See also legend In Appendixes 1, 2 and 3.

with coastal-deltaic coarse-grained elastics. coarse-grained elastics. This formation is charac- The Corona Formation of late Gzhelian tetized by cyclothems (parasequences) of mean (Daixina and Pseudofusulina-Rugosofusulina thickness of about 20 m (range 15 to 40 m). Zones) follows with fine-grained open shelf The Carnizza Formation closes the late Gzhelian pelites (and a single limestone layet in the distal (Pseudofusulina-Rugosofusulina Zones) and is area) alternating with alluvial plain to deltaic made by outer shelf pelites and subordinate conglomerates and sandstones (including some limestones alternating with coarse-grained sand­ thin seems). The dtastic dectease in catbo- stones and quartz conglomerates of deltaic envi­ nate productivity, without major change in phy­ ronment. siographic conditions of the basin, suggest a The "Lower" Pseudoschwagerina Formation of marked tempetate to cool climatic oscillation. latest Gzhelian to Asselian age (Schwagerina This formation is characterized by 30 to 40 m Zone) is composed of massive to bedded shal­ thick cyclothems (parasequences). low-water limestones interlayered by fine-grained The following Auernig Formation, of late marine silicoclastic sediments. Four cyclothems Gzhelian age (Pseudofusulina-Rugosofusulina have been recognized (Homann 1969) and Zones) is composed by outer shelf marine carbo­ recently analysed (Samankassou 1995). The Val nates and pelites alternating with coastal-deltaic Dolce Formation of Asselian age (Schwagerina

GEODIVERSITAS • 1997 • 19(2) 179 Vai G. B. & Venturini C.

Zone) is dominated by terrigenous deposits with Ptamollo Mb (matrix) which have been referred minor limestone intercalations (like in most of to above. Consistent with the above dating are the late Carboniferous) representing delta to pro- also macrofloral and palynomorph data. In fact, delta sequences. ferns ( ex gr. ovata = grand'euryi) of Traditionally, the Carboniferous/Permian boun­ Cantabrian age (late Moscovian to early dary was placed between the Catnizza and the Kasimovian) occur at the top of the Meledis "Lower" Pseudoschwagerina Formations. More Formation (Vai et al. 1980). Also the palyno- recently a position inside the "Lower" Pseudo­ morphs of the lowermost Bombaso Formation schwagerina Formation at the base of the (Francavilla 1966), dated at the Westfalian B or Occidentoschwagerina alpina Zone was suggested so (early Moscovian), are consistent with the age (Kahler & Krainer 1993). Lately, Davydov & of the first fusulinids. It suggests also a possible Kozur (1995) have proposed an even higher earlier Moscovian onset of the post-tectonic sedi­ place at the base of the Val Dolce Formation mentation of the Pontebba Supergroup. (Grenzlandbanke). Waiting for further taxono- The major faunal affinities are found between mic precision we adopt hete a boundary place Carnic Alps, the Dinarides and the Russian still within the "Lower" Pseudoschwagerina Platform to Urals. Floral relationships are more Formation inside the not yet investigated interval close with the Cantabrian region than with above sample SKI 15 of Kahler & Krainer NW Europe. Recent finding of Kasimovian (1993). suggests close affinity with Chinese elements (Perri & Spalletta, pers. comm.; see also The "Upper" Pseudoschwagerina Formation of Forke 1995). late Asselian to early Sakmarian age (Zellia Zone; Forke 1995) is composed of alternating massive reefal and bedded partly marly inner shelf limes­ THE ARTINSKIAN OF THE CARNIC ALPS (Fig. 3) tones. On top of the 150 to 400 m thick Trogkofel The following Ttogkofel Limestone (Sakmarian, Limestone (a complex system of Tubiphytes buil­ Robustoschwagerina and Pseudoschwagerina dups) of Sakmatian age, in places of the "middle" Zones) and the following related Tressdorfer Permian teef-complex, some limestone masses Limestone (early Artinskian, Pamirina Zone) and escaped the Saalic uplift and erosion, showing Coccau (= Goggau) Limestone (mid to late remnants of the Artinskian stage l.s. Artinskian, Misellina Zone) represent as a whole The lower Artinskian is represented directly by a teef-complex of shelf and shelf-edge environ­ the Ttessdorfer Limestone (15 m thick). It is ment, which has been compated with the made of mainly brecciated shallow-water limes­ Capitan Reef of Texas (Fliigel 1981). tone with both extraformational (reworked from the underlying Trogkofel and "Upper" Pseudo­

THE MOSCOVIAN OF THE CARNIC ALPS (Fig. 3) schwagerina Formation) and autochthonous Only the late Mjackovian substage of the components rich in Mizzia, other algae, gastro­ Moscovian is certainly represented in the early pods, fusulinids, other , pelmato- lithostratigraphic units not conformably over­ zoans and bryozoans. It contains sometimes lying the severely folded and thrusted Praeparafusulina lutugini which is an element of Palaeocarnic Chain. The lowermost fusulinids the Russian Pseudofusulina lutugini Zone. A quite found above the unconformity are representative of the Protriticites Zone and include Eostaffella, Paraendothyra, crinoids, , echinoids, FIG. 3. — Stratigraphic correlation of the main Moscovian to molluscs, bryozoans, trilobites and phylloid plus Artinskian columnar sections of the southern Alps (exposures) dasycladacean algae (Kahler & Prey 1963; Selli and the Adriatic Sea (subsurface) and their interpretation (chro- nometric calibration of the chronostratigraphic scale conforms to 1963; Pasini 1963, 1974; Vai et al. 1980; that discussed in the first part of the paper). Key: A, Auernig; B, Venturini 1990). The stratigraphic units bearing Bombaso; B.T., Tarvisio Breccia; C.S., Sesto Conglomerate; M, Meledis; Piz, Pizzul; T-TROG, Trogkofel; R, Ftattendorf; V.G., this fauna are the Malinfier Horizon (matrix), Val Gardena; Bell., Bellerophon. See legend In Appendixes 1, 2 the Meledis Formation and its lateral equivalent and 3 for other symbols.

180 GEODIVERSITAS • 1997 • 19(2)

Vai G. B. & Venturini C.

effective pre-late Kubergandian erosion is sugges­ FINAL REMARKS ted by the frequent occurrence of Tressdorfer- The cotrelation chart in figure 3 shows two and Trogkofel Limestone blocks in the late majot stratigtaphic cycles easily traced along the Kubetgandian to Murgabian Tarvisio Breccia entire western Adriatic and eastern Southalpine (Fig. 3). areas. The first one, represented by the Pontebba The upper Artinskian is represented by the Supergroup, starts with the late Moscovian and Coccau Limestone. This is a light grey massive lasts at least up to the entire Artinskian and part shallow-water limestone quite similar to the pre­ of the Bolorian. It is mainly marine, with conti­ vious two formations. In its upper part a rich nental clastic supply strongly decreasing upwards fusulinid fauna from the Pseudofusulina vulgaris and dominated by western provenance. Zone, including Pamirina darvasica, Thalassocratic conditions culminate with the Minojaponella elongata and Nagatoella aff. orientis early Permian, especially Sakmarian to is found, suggesting an age from Artinskian to Artinskian. It is followed by a remarkable, gene­ early Bolorian or early , at the very ral although differential uplift and etosion, base of the Misellina Zone (Kahler 1992). occurring sometimes during the late Bolorian to Kubergandian interval. How much the relative

THE ARTINSKIAN OF THE NORTHERN uplift is to be related to a concutrent eustatic sea level drop could be argued only upon establish­ ADRIATIC SEA (Fig. 3) The age assigned to the Coccau Limestone above ment of more reliable sea level curves for the Permian. The second cycle begins with the early was confirmed recently from the Amanda 1 well Murgabian spanning the Permo-Triassic bounda­ drilled by AGIP about 50 km E of Venice ry, except for the Venetian Gulf atea showing late (45°24'47"N - 13°00'38"E). The Permian, Permian/ uplift. This is a broadly beneath the mid Triassic Latemar Formation transgressive cycle dominated by the flood plain (late Anisian-Ladinian), was encountered from Val Gardena Formation evolving to the 6840 to 7305 m depth (Sartorio & Rozza 1991). Bellerophon sebkhas and shelf. This trend is It is represented from the top by: quite conttasting with the more common world­ 1. The Amanda Formation, dark to reddish wide Permian regression. marls, clay, silty sandstones with palynomorphs, some carbonate intetcalations with fusulinids (Kahlerina pachytheca of the Neoschwagerina REFERENCES Zone), foraminifera and algae {Tubiphytes) and fine breccias representing the late Permian (possi­ Arthaud F. & Matte P. 1977. — Late Paleozoic strike- bly late Kubergandian to Murgabian). slip faulting in Southern Europe and northern Africa: results of a right-lateral shear zone between 2. The Tarvisio Breccia, composed of reworked the Appalachians and the Urals. Geological Society clasts from the undetlying Coccau (= Goggau) of America Bulletin 88: 1305-1320. Limestone and a red clayey matrix, deposited in Baud A., Marcoux J., Guiraud R. & Gaetani M., a subaerial environment. 1993. — Late Murgabian (266 to 264 m.y.): 9-20, in Dercourt J. et at. (eds), Atlas Tethys Palaeoenvi- 3. The 175 m thick Coccau Limestone, represen­ ronmental Maps. Gauthier-Villars, Paris. ted here mainly by shallow-water platform rud- Castellarin A. & Vai G. B. 1981. — Importance of stone and grainstone facies, including rich Hercynian tectonics within the framework of the Southern Alps. Journal of Structural Geology 3: fusulinid fauna [Pseudofusulina, Praeparafusulina, 477-486. Acervoschwagerina, Misellina), foraminifera, algae Claoue-Long J.-C, Jones P. J., Foster C, Roberts J. [Tubiphytes, Archaeolithoporelld), bryozoans, bra- & Mackinlay S. 1995. — Calibration of late chiopods, pelmatozoans, bivalves, ostracods and Palaeozoic time. XIII ICC-P Krakow 1995, rare Bellerophon. The core taken from the middle Abstracts: 24. Davydov V. I. & Kozur H. 1995. — The position of part of the fotmation was assigned to the the Carboniferous-Permian boundary in the Misellina claudiae Zone of the latest early Carnian Alps compared with the stratotype region. Permian (Chihsianskian or equivalents). XIII ICC-P Krakow 1995, Abstracts: 29.

182 GEODIVERSITAS • 1997 • 19(2) Cyclic Permo-Carboniferous of the Carnic Alps

Dercourt J., Ricou L. E. & Vrielynck B. (eds.), Permian and Triassic periods: an integrated time 1993. —Atlas Tethys Palaeoenvironmental Maps. analysis: 77-97, in Scholle P. A. et al. (eds.), The Gauthier-Villars, Paris, 307 p., 14 maps, 1 pi. Permian of Northern Pangea, volume 1. Springer. Fluegel E. 1981. — Lower Permian Tubiphytes/ Odin G. S. 1994. — (1994). Archaeolithoporella buidlups in the Southern Alps Comptes Rendas de VAcademie des Sciences, Paris (2) (Austria and Italy), SEPM Special Publication 30: 318 : 59-71. 143-150. Pasini M. 1963. — Alcuni Fusulinidi della serie del Forke H. C. 1995. — Lower Permian biostratigraphy Monte Auernig (Alpi Carniche) e loro significato of the Carnic Alps: fusulinid and conodont data. stratigrafico. Rivista Italiana di Paleontologia e XIIIICC-P Krakow 1995, Abstracts: 39. Stratigrafia mio: 337-382. Francavilla F. 1966. — Spore nel Flysch Hochwipfel. — 1974. —Archaeolithophyllum missouriensum Giornale di Geologia (2), 33: 493-526. Johnson, una Rodophycea di interesse stratigrafico Harland W. B., Armstrong R. L., Cox A. V., nel Carbonifero superiore della Toscana e delle Alpi Craig L. E., Smith A. G. & Smith D. G. 1990. — Orientali. Rivista Italiana di Paleontologìa e A geologic time scale 1989. Cambridge University Stratigrafia 80/4: 591-602. Press, 263 p. Roberts J., Claoué-Long )., Foster C. & Briggs D. Homann W. 1969. — Fazielle Gliederung der 1995. — Shrimp dating of the Permian System of Unteren Pseudoschwagerinenkalke (Unter Perm) in eastern Australia. XIII ICC-P Krakow 1995, den Karnischen Alpen. Neues Jahrbuch fuer Abstracts: 122. Geologie und Palaeontologie Monatshefte 5: 265-280. Ross C. A., Baud A. & Menning M. 1994. — A time Izart A., Briand C, Vaslet D., Vachard D., scale for Project Pangea. Canadian Society of Makhlina M., Jaroshenko A., Kossovaya O. & Petroleum Geologists, Memoir 17: 81-83. Goreva N. 1995. — The sequences of the Ross C.-A & Ross J. R. P. 1988. — Late Paleozoic Moscovian, Kasimovian and Gzhelian of the transgressive-regressive deposition. SEPM Special Moscow basin. XIII ICC-P Krakow 1995, Publication 42: 227-247. Abstracts: 58. Samankassou E. 1995. — Cyclic sedimentation pat­ Kahler F. 1986. — Ein Normalprofil der Fusuliniden- terns of the Lower Pseudoschwagerina Limestone Stratigraphie im Obercarbon und Unterperm der (Latest Carboniferous, Carnic Alps). XIII ICC-P Karnischen Alpen. Carinthia II, Sdr. 42: 1-93. Krakow 1995, Abstracts: 127. — 1989. — Die Fusuliniden. Catalogus Fossilium Sartorio D. & Rozza R. 1991. — The Permian of Austriae. H. 2 bl: Foraminifera Palaeozoica, Oester­ Amanda 1 bis well (Northern Adriatic Sea). reichische Akademie der Wissenschaften: 87-295. Giornale di Geologia 53/1: 187-196. — 1992. — Beziehungen der Fusuliniden der Sassi F. P. & Zanferrari A. 1990. — Stratigraphic cor­ Karnischen Alpen zur Paläotethys. Mitteilungen relation forms. Pre-Variscan and Variscan events in Osterreichischen Geologischen Gesellschaft 84 (1991): the Alpine-Mediterranean Belts. Rendiconti della 309-326. Società Geologica Italiana 12 (1989), 2: 95-433. Kahler F. & Prey S. 1963. — Erläuterungen zur Selli R. 1963. — Schema geologico delle Alpi Geologischen Karte des Nassfeld-Gartnerkofel Carniche e Giulie occidentali. Giornale di Geologia Gebietes in den Karnischen Alpen. Geologisches 30: 1-136. Bundes Anstalt, 116p. Vai G. B. 1976. — Stratigrafia e paleogeografia erci- Kahler F. & Krainer K. 1993. — The Schulterkofel nica delle Alpi. Memorie della Società Geologica Section in the Carnic Alps, Austria: Implications Italiana (contr. By G. I. Elter) 13/1: 7-37. for the Carboniferous-Permian Boundary. Fades — 1991. — Palaeozoic strike-slip rift pulses and 28: 257-276. palaeogeography in the circum-Mediterranean Kochansky-Devide V. 1965. — Die ältesten Tethyan realm. Palaeogeography Palaeoclimatology Fusulinidenschichten Sloweniens. Geoloski Vjesnik Palaeoecology 87: 223-252. 18/2: 333-336. Vai G. B., Francavilla F., Ferrari A. & Contarin Krainer K. 1992. — Fazies, Sedimentationsprozesse M. T. 1980. — La sezione del Monte Carnizza und Paläogeographie im Karbon der Ost- und (Carbonifero superiore, Alpi Carniche). Memorie Südalpen. Jahrbuch Geologische B.-A., Wien 135: della Società Geologica Italiana 20: 267-276. 99-193. Vai G. B. & Cocozza T. 1986. — Tentative schema- Leven E. Ya. 1993. — Glavi'e sobiti'iya permskoi tic zonation of the Hercynian Chain in Italy. istorii oblasti Tetis i fusulinidi'. Stratygraphy, Bulletin de la Socìété Géologique de France (8) 1: Geological Correlation 1, 1: 59-75. 95-114. Massari F., Pesavento M. & Venturini C. 1991. — Venturini C. 1990. — Geologia delle Alpi Carniche The Permian-Carboniferous cyclothems of the centro-orientali. Museo Friulano di Storia Naturali, Pramollo Basin sequence (Carnic Alps). Giornale di 36, 222 p. Geologia 53/1: 171-185. — 1991. — Tectonics and stratigraphy of the Menning M. 1995. — A numerical time scale for the Pramollo Basin (Carnic Alps). Giornale di Geologìa

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53/1, 240 p. logia del Sudalpino centro-orientale, Guide Venturini C, Ferrari A., Spalletta C. & Vai G. B. Geologiche Regionali SGI, Bologna: 305-319. 1982. — La discordanza ercinica, il tardorogeno e Ziegler P. A. 1988. — Evolution of the Arctic-North il postorogeno nella geologia del Passo di Pramollo, Atlantic and the Western Tethys. AAPG Memoir, in Castellarin A. & Vai G. B. (eds), Guida alla geo­ 43, 198 p.

Submitted for publication on 5 April 1996; accepted on 11 October 1996.

APPENDIX 1: KEY TO AND SEDIMENTARY STRUCTURE SYMBOLS

FOSSILS SEDIMENTARY STRUCTURES

if Acritarchs, Chitinozoa «f Gastropods ^ Bioturbation S3 Algae Graptolites JJ. Large scale cross bedding © Ammonoids, Nautiloids 4" JL Small scale cross bedding (r: ripple) ^J^Amphibians qd Nannofossils = Parallel bedding X Bivalves «*• Orthocones s= Lamination Q Brachiopods c7 Ostracodes Channel spine © Palynoflora Slump Y Bryozoans <§> Plantae (wood) -o- Tempestite gf Charophytes £T Plantae (leaves) © Conchostracans Radiolarians Conodonts jfc Reptiles • Corals S Sponges 4 Crinoids A Sponge spicules * Echinoderms ifW Stromatoporoids •* Shells indet. 0 Fusulinids ^/ Bioclasts indet.

184 GEODIVERSITAS • 1997 • 19 (2) Cyclic Permo-Carboniferous of the Carnic Alps

APPENDIX 2: COLUMNAR SECTION LEGEND

MAIN COLUMN DEPOSITIONAL ENVIRONMENT Shallow carbonates 11 I Continental, Lacustrine 6 orange gold yellow I 2 I Evaporites 7 Pelagic rise pink olive green I 3 I Deltaic 8 Deep carbonates pale yellow light blue I 4-5 I Shallow marine elastics Erosional hiatus green I 9 I Deep marine elastics III Non-depositional hiatus blue I 10 I Deeper marine elastics Lack of data brown LITHOLOGY *• A A Breccia s=silicoclastic o. o. Sand, conglomerate Turbidites I v=volcanoclastic • 9- 5 c=carbonate

Sand Organic shale

Sand, silt, shale Dolomite

T~7T Carbonate, sand Sulphate

p=packstone w=wfcTe°toSne [ D • J Halite I m=mudstone Reefal carbonate, bindstone Coal

I j j] Carbonate, shale A AChert , radiolarite

Pelagic carbonate X X Volcanics

Nodular carbonate II II Volcanoclastic deposits o Concrétion (Fe: iron, etc.) \l-~-l j Shale, some carbonate 0 Oolite p Phosphate Shale B Bauxite Pa Paleosol • Oil, gas SIDE-COLUMN

Erosion, unconformity

x\ Low / High angle unconformity TR RE Transgression, regression

R W Rift/Wrench induced u c Regional uplift/collapse

I F Inversion, folding M * + Metamorphic, volcanics, intrusives

GEODIVERSITAS • 1997 • 19(2) 185 I Vai G. B. & Venturini C.

APPENDIX 3: MAP LEGEND

DEPOSITIONAL ENVIRONMENT AND MAIN LITHOLOGY

Mainly continental elastics orange 7 Pelagic rise (c=coarse; f=fine; l=lacustrine, d=desertic, lateritic) olive green

Evaporites pink 8 Deeper marine carbonates (t=and elastics; c=and carbonates) light blue

Deltaic shallow marine, mainly sands 9 Deeper marine elastics pale yellow blue

Shallow marine, mainly shales 10 Deeper marine, mainly sands pale green (turbidites) light brown Shallow marine, carbonates and elastics 11 Basins floored by oceanic green lithosphère dark blue Shallow marine, mainly carbonates gold yellow TECTONIC SETTING AND LITHOSPHERIC TYPE | 13 Inactive fold belt Normal 12 | Foreland lithosphère 12 I Anorogenic craton Normal lithosphère Thin ..fiy.' I Foredeep basin lithosphère Rift :14 I Active fold belt Thick lithosphère 11 J Oceanic lithosphère dark blue VOLCANIC ACTIVITY 15 J Basaltic plateau dark red * Anorogenic 16 Porphyrie plateau light red it Orogenic AUXILIARY SYMBOLS Fault, wrench, normal Basin margin OL

1 Major thrust fault Direction of clastic influx 1 active, 2 inactive 2 . 1 B and A subduction Limit of palaeoenvironment 1 active, 2 inactive

finnn Accretion wedge I I I I I I I I Continental slope

Active sea-floor spreading Major anticlinal axis axis and transform fault As above, with magnetic v "J Isopachofthe (stage) anomaly

GEODIVERSITAS • 1997 • 19(2) 186

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