Aptian to Campanian Calcareous Nannofossil Biostratigraphy from the Bottaccione Section, Gubbio, Central Italy

1\ovembre lu0_

APTIAN TO CAMPANIAN CALCAREOUS NANNOFOSSIL BIOSTRATIGRAPHY FROM THE BOTTACCIONE SECTION, GUBBIO, CENTRAL ITALY.

FABRIZIO TREMOLADA

Receit,ed December 27, 2Aa1; acceptecl May 3, 2002

Key \X/ords. Calcareous Nannofossils, Cretaceous, Biostratìgra- Alvarez et al. (1977), Lowrie et al. (1982) and Umbria-Marche Basin. Ph)', Napoleone et al. (1983) provided detailed paleomagne- Riassunto. L'analìsi biostratìgrafica condotta sui Nannofossili tic analyses. In addition, chemostratigraphic srudies calcarei delle Formazioni degli Scisti a Fucoidi e della Scaglia ha per- based on oxygen, carbon and strontium s/ere performed messo di migliorare la risoluzione stratigrafica deLla sezìone del Bot- by Renard (1986), Corfield et al. (1991), Jenkyns et al. taccìone (Bacino Umbro-Marchigiano, Italia Centrale) nell'intenallo (1994) and Stoll 8r Schrag (2000). Aptiano superiore-Campaniano. Inoltre, caratteristici bioeventi Monechi & Thierstein (1985) established a addizionali quali I'ultima comparsa dr Assipetra infracretacea larsonii e Rucinolithus terebrodentarius youngii, la prìma comparsa dr Parhab- detailed Eariy Campanian to Late Eocene nannofossil do/íthus achlyostawrion e di esemplari sovradimensionatì dt Bìscutum stratigraphy, recenrly refined by Gardin et al. (ZO0t), constdns potrebbero essere urilizzati per migliorare 1a stratigrafia a calibrated with the magnerosrratigraphy of the Bottac- Nannofossìli calcarei alle basse latitudini nell'intervallo Aotiano suoe- cione section. The nannofossil riore-Albìano. biostratigraphy previous- ly proposed for the Aptian to Santonian interval by Abstract. Late Aptian-Campanìan biostratigraphic investiga- Monechi (1981), Erba (19SS) and Ghisletti Er Erba in tions performed on calcareous nannofossils provided a refined strati- Premoli Silva & Sliter (1994) is here refined based on graphic resolution of the a Fucoidi Scisti and Scaglia Formations in the updated taxonomy and bio-chronostrarigraphy. Bottaccione section (Umbria-Marche Basin, Central ltaly). Additìon- al bioevents such as the Last Occurrence (LO) of both,4 ssipetra ìnfrac- This study documents a high-resolution bio- retacea larsonìi and Rucinolitbus terebrotl,entarius youngii and the First stratigraphy using calcareous nannofossils from the Occurrences (FOs) of Parhabdolithus acblyostaurion andlarge Biscu Upper Aptian to the lowermost Campanian of the Bot- tum constdns were detected and might be used to rEfine rhe Late Apt- taccione Gorge. The nannofossil events are directly cali- ian-Albian biostratigraphy at low latitudes. brated to the foraminiferal biostratigraphy reported by Premoli Silva & Sliter (1994), since both studies have been conducted on the samDles. Introduction same

The sediments exposed in the Bottaccione Gorge Geological setting and lithology have been investigated by several authors owing to the continuous exposure from Upper Jurassic ro lower The Bottaccione, section is located close to the Upper Eocene and the only modest tectonic distur- town of Gubbio along the road-cur from Gubbio to bances. Many studies on lithosrratigraphy, biostratigra- Scheggia in the Umbria-Marche Basin, Central Italy phy and magnetostratigraphy of the Bottaccione succes- (Fig. 1). Flere a fairiy continuous pelagic (lower to sion were performed in the last century. Renz (1936) upper bathyal) sedimentation characrerizes the Jurassic proposed an Aptian-Eocene biostratigraphy. The plank- to Paleogene interval. Very condensed or incomplete tonic foraminiferal biostratigraphy was carried out by sequences suggest the occurrence of ancient structural Luterbacher & Premoli Silva (1962), Premoli Silva highs. (1977) and Premoli Silva & Sliter (1994). Mohler (1,966) Above basement and Triassic evaporires, the Juras- tried to combine the nannofossil and planktonic sic and Cretaceous sedimentary succession is mainly foraminifer biostratigraphl-. Arthur 8r FiscÀer 0977) composed by calcareous to marly calcareous lithotypes and Arthur (1979) surveyed and measured the section. containing nodules and layers of chert.

Dipartimento di Scienze della Terra, via Mangiagalli 34,2a133 Milano, Italy; e-mail: fabrizìo.tremolada@unimì.ìt t11 F. Tremolada

ca and Scaglia Rossa. A total of 354 samples of limestones, marly limestones and marlstones were prepared using standard techniques (Monechi Er Thierstein 1985); no ultrasonic cleaning or centrifuge concentra- tion were applied in order to retain the original biogenic composition of the sample. Smear slides, prepared with Norland Optical Adhesive, were analyzed using standard light microscope techniques under cross polarizers and trasmitted light at 125aX magnification. Due to calcite dissolution and/ or overgrowth, preservation and abundance of calcareous nannofossil species rnày vary significantly. Thus, to characterize preservation a simple code system (Ocean Drilling Pro- gram code) has been adopted and is listed beiow: VG (very good) = no evidence of dissolution andl or overgrowth is present; there is no alteration of primary morphological characteristics, and specimens appea;r diaphanous; specimens are identifiable to the species level. G (good) = little or no evidence of dissolution and/or overgrowth is present; primary morphological characteristics are only slightly altered; specimens are identifiable to the species level. M (moderate) = specimens exhibit some etching andl or overgrowth; primary morphological characteristics are sometimes altered; however, most specimens are Fìg. 1 - Location map of the Bottaccione section (after Premoli Sìlva Er Sliter 1994). identifiable to the species level. P (poor) : most specimens exhibit overgrowth or dissolution; primary morphological characteristics are ln particular. the succession outcropping at Bot- sometimes destroyed; fragmentation has occurred; taccione and studied in this paper is referred to Scisti a species identificarion is often impaired. Fucoidi and Scaglia Formations. Estimates of the totai calcareous nannofossil The Scisti a Fucoìdi Formation of Early Aptian- abundance, compared to that of other biogenic particles Late Albian age consists of alternating marlstones, marly and inorganic components, were recorded as follows: limestones, limestones and organic-rich black shales. C (common) = >51o/o of all particles, The contact between the Scisti a Fucoidi and the overly- F (few) 11''k-50"/. of all particles, ing Scaglia Formation is transitional; the marly intervals = R (rare) : 1o/'-1a"k of all particles' decrease, whereas the limestones become dominant. T (trace) <1o/" of all particles, and The Scaglia Formation (Late Albian-Oligocene) = B (barren) : no nannofossils are present. is composed of limestones and marly limestones with Estimates of the relative abundance of calcareous lenses or bands of chert. It is possible to subdivide this nannofossil species in the studied assemblages, were formation into four members on the basis of lithologi- determined as follows, cal characteristics and color (Crest a et aI. 1 989): Scaglia D (dominant) = >51o/o of the total assemblage, Bianca (Late Albian-Early Turonian) , Scaglia Rossa A (abundant) : 11%-50% of the total assemblage, (Early Turonian-Middle Eocene), Scaglia Variegata C (common) : 2"k-10o/o of the total assemblage, (Middle Eocene-Late Eocene) and Scaglia Cinerea F (few) 0.1"k-1"k of the total assemblage, and (Late Eocene-Oligocene). The most prominent feature = R (rare) : <0.1."k of the total assemblage. of the Scagiia Bianca is the presence of organic-rich black shales and siliceous sediments (Bonarelli Hori- zon, Oceanic Anoxic Event 2) in the uppermost Ceno- manian. Biostratigraphy and discussion

The nannofossil biozonation adopted in this study (Figs 2,3) is that of Roth (1,978) and is regarded as stan- Material and Methods dard as summarized in Perch-Nielsen (1985)' The NC Biostratigraphic investigations were performed on biozonation provided by Roth (1978) and the improve- samples collected from the Scisti a Fucoidi, Scaglia Bian- ments proposed by Bralower et al. (1995) are largely C al car e o u s nann ofo s s il b i o s tratigrapby 443

9> U)z lil- LTTHOLOGY NANNOFOSSTL (r I >í=a o F G.arca z 190 C. obscurus Laeviheterohelix L. cayeuxii a D.asymetrica 180 M. concava I R. anthophorus V.eggeri M. decussata z z 170 U) G.lapparenti O a M. furcatus 160 o C.fornicata z z fr (J 150 /*____ D.concavata z _ -E. oclopetalus (t= - Q. giganteum 140 - - -'- (r K. magnificus O T /\ H.flandrini a O IJU îf .ra _ p. asper \ z H.helvetica uJ /-t\ / -/- ,L.moratus \ 120 íJ=== 1] E' ocropetatus, a :_J lu. glganteum, H.helvetica lE.eximius rotaliporids 110 _----- W.archaeocrét. îY R-=- Micula so. = - -) G.bentonenitis -.---.] - ** Q. gartneri 100 f v.èniàstius (ú o |-..---- ./ E z È a..a C. kennedyi / D.imbricata =q z J -- -- 90 \. \. \. G. obliqúum Het. z - p. m - columnata ppenninica E IY 't'' 'M. decoratus o D.algeriana BO o '-. z = o C. dispar z z stù TIJ C'= R.cushmani É. 70 a C) z(-) P.gibba Rgre () C. kennedyi R.reicheli T.R. * a tu 60 O R.brotzeni inellids P.buxt F B.breggiensis 50 Lll R. inegularis (E P. stephani (J ó R,ticinensis 40 ó E,lufrreelffgl_!! () E. monechiae T. roberti z 30 3sÈH s l Q. eneabrachium = c c.y tL z : sl.s E J P. achlyostaurion glib 20 ,- * Laroe B. constans B.breggiensis Fl- tr riòiÀeJrJ C. dispar 10 a lA. inlr. hrsonii H.rischi primula T.primula C) C. ehrenberoii | R. ter. vounoii preligp. a P. columnàta - _! 0 A. infracretacea T.bejaoua. APT

iT?.rTrÉl thick bedded thick & medium thin bedded marl and marl marl ,,black limestone and shale,, I Oceanic Anoxic Event 2 bedded-:=:-I limestone limestone marly limestone clayey marl

Fig. 2 - Lithostratigraphic log, foraminiferal (after Premoli Silva & Sliter 7994) and nannofossil evenrs recognized at Bottaccione. F. Tremolada

t- È 6 o N ó Bralower Erba et al, Present ÉE o et al. 1995 1995 study Fxg) .= E lE: ìfE o o .t2, E # EE f;E U' UU t H. navt 19 \lC -- M. fuîcatus A. parcus parcus l3F 18 9 Lgnilii / CAM G. elevata cc 18 ,,C. verbeekii A ryrbifPrI,î-^,,. ,r, ^ 18 a J A.p.constriclus | / zL, UtUrAtUJ 83.5 parca . A parcus parcus -J B. #-:lÉAaIEl,,n cc1 NC ---E.llonlis 17 ^ SAN D. asymetria 11 J L. cayeuii '&9Y!us v. orrrrii !-fo!Ayi"#i L cayeuxii --l--L. Seqrenanus NC --l--.1. oriil/li r R. anhophorus 16 16 ,\R. ahl'tophorus M.decussata - M. decussata -rM.decussata coN D. concavata NC 15 80 13 tc L L.septenaius J M.furcatus L M.furcatus t M.furcatus NL; E. octoretalus Dorinitiva M.sioali 14 gigànteum - 12 14 E.exinius - Q. , xlfwiiticus lE.octoqetalus TUR tK.magnifiws J L.maleformis ---l H. helvetica cc NC 13 L. moratus lL!'Aganteum P. a soe r- -jj- - 1i-eWlUs- tl P. aser :-!r?::_Miculasp.- - 90.5 b ,Q.gartneri . W.archaeocretacea 12 -'-M.úíagius 4'. C. kennedyi, P. asper, 1-----U.O?nnef, cc 4-4. albianus *-v. A albianus R' cushmani chrastius +'r-:-W#1'Jy,t D.argeriana 10 NC CEN 11 JM. decoratus, L. acutus n .^:^r^ti fr:Aleetr 11 ---r--ì\\--ì---:F:3,ó1ff%l3l M. de@ntus L, acutus -'C.dwar R. brotzeni cc C. kennedyi h - kennedyi tC. l

R. tbinensis --t E. turrieiffelii ----t E. turrieiffelii ----L E.turrisdtîelii F. subflblnensls ^oó"ò J E. nonechiae b ----t small Eiffellithus , Q. eneabraúiun a praeticinensis NC $ ' P. achlyogaurion ALB ; L E. cf. eximius primula cc ' ' Larye B. cgnstans T. A. albianus, n A. albianus --t r T.phaceloas r A.ab)ianus -H. rixhi T. orionatus NC 11 -S---' C. $gnum 8 8 h ' 'C. dispar H. planiqira ----.: C. ehrenbergii + C.ehrcnbenii | , H. albiensis A. htt. hîsonii L P. columna6 lR. tet. yott1qil F P. columnata .--t P, nlumnata APT cc NC l-:'A infraqetacea T. A. infracretacea beiaouaenss 7 7 7 l-

Comparison amongst the bioevents detected at Bottaccìone and previous biozonations. Planktonic foraminifers from Premoli Silva & Sliter (1999). The gray pattern indicates the time interval ìnvestigated.

based on DSDP/ODP results and allow a good correla- low degree of nannofossil preservation. tion between nannofossil and planktonic foraminifer In general. the Scaglia displays a nannofossil biostratigraphic data. preservation ranging from poor to moderate and the The Sissingh (1,977) scheme was constructed on overall nannofossil abundance is low. By contrast' cal- results from land sections (mostly in Europe). but his careous nannofossils in the Scisti a Fucoidi are just planktonic foraminiferal data are often unavailable or slightly altered, thus allowing the identification at different from those obserwed bv Premoli Silva 8r Sliter species level and their abundance ranges from few to (1994\ at Bottaccione. common. The UC biozonation, recently published by Bur- The bottom of the investigated succession is nett (1998), does not allow a good calibration with assignable to the Late Aptian NCZ nannofossil zone planktonic foraminiferal biozonations and most nanno- based on the occurren ce of Eprolithws floralis in the low- fossil events are recognizable only at higher latitudes or ermost sample investigated (sample Apt 4 - 0.60 m). The in better preserved material. NC7/NC8 zonal boundary is placed at the FO of Pre- Most nannofossil assemblages found are domina- discospbaera columnata (sample Apt 19 - 5.86 m) . This ted by Watznaueria barnesae. a species very resistant ro zonal boundary is preceded by the LO of Assipetra diagenetic modifications (Roth & Krumbach 1986). infracretacea (sample Apt 1.7 - 5. 48 m), whereas A infr. Indeed, large amounts of W barneasae usually indicate a larsonii disappears at 7.33 m (sample Apt 22) associated C alcare o u s nannofo s s i I b i o stratigrap hy 445

with the LO of Rucinolithus terebrodentarius youngii. A. 64) were recognized. The FO o[ lrrge-sized specimens infr. larsonii and R. ter. yowngii represent the large-sized of B. constans is a peculiar event of the Tethyan Albian morphotypes of ,4. infrauetacea and R, terebrodentarius, documented as B. magnulol sensu Erba et a\. (1999) at respectively and their stratigraphic range is restricted to the Cismon drillcore (Northeastern Italy, Venetian the Aptian stage (Tremolada Er Erba2002). alps), Erba (1988) at the Piobbico drillcore (Umbria- The FO of Cribrospbaerella ehrenbergii lies at 8.60 Marche Basin, Central Italy) and Bellanca et al. (in m (sample Apt 28) indicating an earliest Albian age. Ca/- press) at the Calabianca section (Nortwestern Sicily, cwlites dispar was first observed in the sample Apt 42 bis Southern Italy). (1,4.75 m) and displays a continuous occurrence Several authors (e.g. Bralower et al. 1995; Bown et although characterized by low abundance. This species al. 1998) reporr the FO of P acblyostaurion in the Late was established by Al-Rifaiy et al. (199A) and there are Aptian, but at the Bottaccione section, the Cismon still limited data concerning its distribution. The LO of d.ill.or. (Erba et aL 1999),the Piobbico drillcore (Erba C. dispar was detected in the Bottaccione section xt 1988) and the Calabianca section (Bellanca et al. in 97.a9 m (sample B 458), of Late Cenomanian age, sug- press) this event is dated as Middle Albian. This dis- gesting a slightiy later disappearence than reported by crepancy is probably due to different criteria in the ta- Al-Rifaiy et a1. (1990). xonomic identification or a biogeographic control ham- Axopodorbabdus albianus is extremely rare in the pering a widespread and simultaneous first occurrence samples investigated and its first occurrence is located at of P achlyostaurion. 15.74 m (sample Apr 47). The FO ol A. albianus marks The LO of Rucinolithws irregularis lies at 54.65 m the NCS/NC9 zonal boundary, within the Tìcinella (sample B 58) in the Late Albian within the Rotalipora primwla foraminiferal Zone (Premoli Silva Er Sliter 1994, appenninica foraminiferal Zone (Premoli Silva Er Sliter 1999). The top of the NC9 nannofossii zone is defined 1994) and the FO of Corollithion leennedyi at 68.71 m by the first occurre nce o{ Effillitbus turriseffilii at 37.80 (sample B 193), within the Rotalipora reicheli Zone (Pre- m (sample Apt 89) preceding the FO of Rotalipora tici- moli Silva Er Sliter 1994) indicating an Early Cenoma- nensis ar 43.10 (Premoli Silva & Sliter 199a).The FO of nian age. E. turriseiffelll is anticipated by the occurrence of Effil- The FO of the foraminifer Rotalipora brotzeni litbus monechiae (Bown et al. tllS) at 35.55 m (sample was recognized at 61.2A m (Premoli Silva & Sliter 1994). Apt 8a). This taxon may represent the Effillithus c{. E. C. kennedyi displays a quite continuos presence eximius documented by Bralower et al. ( 1995) or the through the Cenomanian up to 110.28 m (sample B small Effillithus reported in Erba et a1. ltees;. 561), just prior to the deposition of the Bonarelli Hori- Within Zone NC9 other events such as the FOs of zon. In several sections such as Novara di Sicilia, North- large Biscutum constans at 1.6.68 m (sample Apt 48) and eastern Sicily (Tremolada unp. data) and Eastbourne, Parbabdolitbws achlyostaurion at 23.61 m (sample Apt United Kingdom (Pau1 et al. 1999) the LO of C.

PLATE 1

All specimens at x2OO0 magnification. Frg. 1 - Etlfellithus eximius, crossed nicols, sample B 580. Fig. 2 - EiffeÌlihus eximius, crossed nicols, sample 1.61161. Figs 3,4 - Calculithes dispar, crossed nìcols, sanple 860, same specimen. Fìgs 5,6 - Micula sp., crossed nicols, sample 16116.1, same specimen. Figs 7,8 - Corollithion kennedyi, crossed nicols, sample B 558, same specimen. Fìg.9 - Mìcula cÍ. decussata, crossed nicols, sample 1.6lll2.Frg. l0 - Mícula decussata, crossed nicols, sample 161114. Frg.7I - Rwcinolithus irregwlark, crossed nicols, sample B 19. Fig. 12 - Quadrum eneabrachiwm, crossed nicols, sample Apt 73. Fig. 13 - Rucínolithus Dayi, crossed nicols, sample 16/104R. Fig. i4 - Biscutum constdns, crossed nìcols, sample B273.Fig. 15 - Large B. constans, crossed nicols, sample B 101. Fig. 16 - Large B. constans, trasmitted light, sample B 123.Frg. 17 - Aspidolithus pdrcus pdrcils, crossed nicols, sample 161100R. Fìg. 18 - Calculithes obscurus, crossed nicols, sample 161102. Fig. 19 - Kamptnerius magnificus, crossed nicols, sample 16/175. Fig. 20 - Kamptnerius magnificus, crossed nicols, sample 161175.

PLATE 2

All specimensat x2O00magnification.Figsl,2 -Microstauruschiastius,crossednicols,sampleB554,samespecimen.Fig.3 -Microrhabdulwsdec- oratus, crossed nìcols, sample B 535. Fig. 4 - Prediscosphaera columnata, crossed nicols, sample Apt 20. Fig. 5 - Martbasterites furcdtus, trasmÍ- r"lli-Lt ".-.l"lAl14,ì F;g.6-Marthasteritesfurcatus,trasmittedlight,samplel6/1a5.F'ig.7-Marthasteritesfurcatus,trasmittedlight,sample 161145. Fig. 8 - E/feLlithus tuniseiffeliì, crossed nicols, sample 161102R. Fig. 9 - Parhabdolìtus achll,ostaurion, crossed nicols, sample B 53. Fig. 10

- Parhabrlolitus achlyostaurion, crossed nicols, sample B 58. Fig. 1 1 - Parbabdolitws achlyostauríon, crossed nicols, sample B 19 Ftg. 12 - Parhab d.olitws acblyostaurion, crossed nicols, sample B 24. Fig. 13 - Quadrum gartneri, crossed nicols. sample B 5 70. Fig. 1.4 - Reinhardtites cl. anthopho- rzzs, crossed nicols, sample 161101. Fig. 1,5 - CribrospbaerelLa ehrenbergll, crossed nìcols, sample B 421. Fig. 1.(t - Assipetra infracretacea larsonii, crossed nicols, sample Apt 22.Fig. 17 - Gartnerago obliquum, crossed nicols, sample B 546. Fig. 1.8 - Etffellitbus trabeculatus, crossed nicols, sample B ,{21. Fig. 19 - Rucinolithus terebrodentarius loungìi, crossed nicols, sample Apt 11. Fig. 20 - Rucinolithus terebrodentarìus youngìi, crossed nicols, sample Apt 12. F. Tienolada Pl. 1

E. eximius C. dispar

Micula sp. C. kennedvi

M. cî. decussata M. decussata R. irregularis Q. eneabrachium

B. constans large B. conslans

A. parcus parcus C. obscurus K. magnificus Pl.2 C a I c are o u s n an n ofo s s i Ì b i o s n'atigrap hy

M. chnsÍius M. decoratus P. co/umnaÍa

M. furcatus E. turiselffe/ii

P- achlyostaurion

F. cf. anthophorus C. ehrenbergii A, infr. larsonii

G. obliquum E. trabeculatus R. ter. youngii 418 F. hemolada

kennedyi was re cognized within the Bonarelli Horizon Dicarinella concd'L)ata (sample 1'6/149 - 119 m). M. fur- equivalents. This apparent discrepancy is possibly due to catus is always rare at Bottaccione. the iack of calcium carbonate in the uppermost Ceno- The NC15/NC76 zonal boundary is placed at the manian black shales at Bottaccione, but Luciani Ec FO of Broinsonia lacunosa, but this taxon was never Cobianchi (1,999) detected the LO of C. kennedyi just detected at Bottaccione. In fact, B.lacwnosa is a delicate above the Bonarelli Horizon at Antruiles, Northeastern coccolith susceptible to diagenetic modifications and its Italy. occurrence is conditioned by the degree of preservation The interval immediately preceding the Bonarelli of the investigated material. The FO of Micula decussata Horizon is marked by several nannofossil events such as at 173 m (sample 161125) was used to replace the FO of the FO ol Microrhabdulus decoratus at 107.92 m (sample B. lacunosa and to indicate the base of the Zone NC16 B 533), the LO of P. columnata at 108.77 m (sample B (Bralower et al. 1995). 542) and the FO of Gartnerago obliquwm at 109.35 m Reinbardtites anthopborus was first obser-ved at 175 (sample B 546), which defines the base of the nannofos- m (sample \611.23). This event preceds the FOs of Mic' sil zone NC12. It was not possible to subdivide the wla concaoa at 1.79 m (sample 16/119), Lwcianorbabdus zones NC 10 and NC 1 1, since the zonal marker cayeuxii at 184 m (sample 16/ 1,14) and Calculitbes obscw- Lithraphidites dcutus shows a too spotty distribution. rws at \97 m (sample 1.6/1A7). M. concaoa, L. cayeuxii The extinction of the foraminiferal genus Rotali- and C. obscwrws are usually rare and they display a spot- poralies at 111 m (Premoli Silva & Sliter 1994) slightly ty occurrence in the Bottaccione section, whereas R. below the Bonarelli Horizon; this event represents the anthopborus shows a rather continuos distribution. L. base of the Wbiteinella archaeocretacea Zone. The top of cayeuxii is a cosmopolitan taxon and recorded in low this zone is placed at the FO of Hekoetoglobotruncana abundances everl'where, but it seems to prefer shallow helaetica (sample 1.61177 - 117 m). water environments (Thierstein 1976). In this work I The LO of Microstaurus chiastiws was observed at used the FO of L. cayeuxii to define the base ol Zone 112.03 m (sample B 56,+), whereas the FO of Quadrum NClZ following the modification proposed by Bralow- gartneri (: Tetralithws pyramidus of Sissingh 1977 and er et al. (1995). Roth 1978) lies at 112.59 (sample B 568) and defines the The FOs of foraminif ers Dicarinella asymmetrica base of the zone NC13. These events are recorded and VentiLabrella eggeri were detected in the same-'sample worldwide across the Cenomanian/Turonian boundary. at 181 m (Premoli Silva & Sliter 1994). The FO of Micula sp., recognized at 1 12.73 m (sample B Vithin Zone NClT several bioevents were recog- 569), preceds the LO of Parbabdolitus asper at 11'1.68 m nized: the LOs of Q. eneabrachium (196 m - sample (sample B 579). Micwla sp. may be correlatable to Micu- 1.6/102) ) and L. moratus (216 m - sample 161108R) and Ia stawrophora as documented by Roth (1'978) from the the FOs of Rucinolithus hayiì (205 m - sample 149G4) lowermost Turonian. and Arkhangeskiella cytnbiformis (217 m - sample Kamptnerius magnificus was first observed at 1'1'9 161 1o6R). m (sample 16/L75), although extremely rare, and is used The FO ol Aspidolithus pdrcus pd.rcws lies af 22a m to identify the top ol Zone NC13. \Tithin Zone NC13 (sample 161104R) and defines the NC17/NC18 zonal several bioevents were recognized: the FOs o{ Eiffel- boundary and the Santonian/Campanian stage bound- lithus eximius, Qwad.rum giganteum and Eprolithus ary. The FO of A. parcus parcus is a well established octopetalws at 1.12.91 m (sample B 570), the FO of event recognizable at both low- and high-latitudes Lithastrinws moratus at 1,13.07 m (sample B 57 I) and the lBralower et aI. 1995\ and correlatable to the end of the FO of Lwcianorhabdus spp. at 118 m (sample 16/1.76). normal superchron C34N. Q. gigantewm is usually rare in the Bottaccione The LO o{ D. asymmetrica ts recorded at 221.5 m section, whereas E. eximius, L. moratus and E. in the Early Campanian (Premoli Silva & Sliter 1994). octopetalws display a continuous stratigraphic distribution, even though the poor preservation can sometimes hamper the identification of E. octopetalus and L. mora- Chronostratigraphy tus. The LOs of Q. giganteum (1,38 m - sample 16/160) The integrated stratigraphy proposed in Fig. 2 and E, octopetalws (1.41. m - sample t6/1.57 ) were recog- summarizes the foraminiferal and nannofloral biozona- nized within Zone NC14. The stratigraphic range of Q. tions at Bottaccione. Nannofossil and foraminifer gigantewm and E. octopetd.lus is slightly different from events detected in the samples investigated may be used that reported by Varol (1992) who recorded these events to approximate the stage boundaries at low latitudes in the Early Turonian. when detailed ammonite investigations are not available. The FO oÍ Martbasterites furcatus defines the base The geomagnetic polarity time scales cannot be inte- of Zone NC15 and this event was observed at 150 m grated with microfossii events over the time interval (sample 16/148) postdating the FO of the foraminifer investigated since the Long Normal Superchron spans C a lcar e o u s nannofo s s il b i o strati grap hy

from the Early Aptian ro the Campanian (e.g. Alvarez et boundary since it slightly preceds the FO of W devo- aL.1977). nense af lowlatitudes, whereas Burnett (1998) reported The Aptian/Aibian stage boundary is not easily the first occurrence of Q. gartneri from the Lower T[ro- recognizable and there are still uncertainties on rhe nian (Mammites nodosoides ammonite Zone) at high lat- ammonite datum to be used (e.g. Bréhéret et al. 1986; itudes. Hart et aI. 1996). Kennedy et al. (2000) proposed to use The Turonian/Coniacian boundary can be approx- the FO of the ammonite Leymeriella tardefurcata to imated using the FO of M. furcatus (Sissingh 1977; indicate this boundary. Bown (in Kennedy et al. ZOOO) Perch-Nielsen 1983, 1985; Bralower et al. 1995; Vatkins suggested the FO of the small, circular specimens of P et aI. 1996), whereas it is not possible to define the columnata or the LO of Broinsonia viriosa to approxi- Coniacian/Santonian boundary since there are not bio- mate the ammonite-defined Aptian/Albian boundary. events directly correlatable to this boundary. The entry Bown (in Kennedy et al. 2OOO) studied the morphologi- of the foraminiferal group of the ventilabrellids may be cal characteristics of P columnata differentiating rhree used to best approximate the Coniacian/Santonian evolutionary stages: elliptical shape (Prediscospbaera boundary as reported by Salaj (1980, 1984) in Tunisian spinosa of many authors), near-circular shape and circu- sections, but this event was detected at the same level as lar shape. the FO oÎ Dicarinella asymmetrica ar Bottaccione, thus However, B. piriosa was not found at Bottaccione indicating an Early Santonian age (Premoli & Sliter, and it was not possible to differentiate between near-cir- ree4). cular and circular morphotype s oÍ P coLumnata. In facr, The Santonian/Campanian boundary is equated to the specimens of P columnata recorded in the samples the magnetic chron 34N/33R boundary (e.g. Lom- analyzed are affected by overgrowth or etching hamper- merzheim 8r Hambach 1992;Bralower et a1. 1995; Grad- irg the study of sizelshape variations. The stein et aI. 1995) and correlates with the FO of ,4, parcus Aptian/Albian stage boundary is usually placed in the p1rcus. lower part of the Hedbergella planispira foraminiferal Zone (Premoli Silva & Sliter 1994, 1999; Bralower et al. 1995), between the FOs of P columnata and C. ehren- Conclusions bergii. Several A. infr. larsonii and R. ter. yowngii have their last important nannofossil events wcre rccog- occurrence within the lower part of the foraminiferal nized in the Bottaccione section, even rhough the nan- Zone Hedbergella planispira and they may be used to nofloral preservation is poor. A few zonal markers (e.g. L. acutus, B. virìosa and B. lacunostt) missing or show approximate the boundary, since these subspecies were ^re a occurrence only recently established (Tremolada 8r Erba 2002) and spotty in the samples analyzed. perhaps they need a further documentation of their The nannofossil and foraminifer events found at Bottaccione stratigraphic range, ecologic significance and biogeo- are correlated in Fig. 2; this scheme may represent a -.. ^L; ^ good integrated stratigraphy for Italian sec- The FO of the planktonic foraminifer Rotalipora tions and the Tethys area in general. Additional nannofossil events herein as globotrwncanoides (: R. brotzeni) best approximates rhe p.oporèd such the FOs of large B. constans, P achlyostaurion and Albian/Cenomanian boundary (Bralower et aI. 1995; the LOs of R. terebrodentarius and Gale et aL.1996; tóger & Kennedy 1996; Premoli Silva youngii A. infracretacea larsonii may be used also in other regions in order & Sliter 1999).The FO of R. globotruncanoides lies at 61 ro enhance the resolution m between the LO oî R. irregu/aris at 54.65 m and the of the currently available biozonations. FO of C. kennedyi at 68.74 m in the Bottaccione secrion. The Cenomanian/Turonian boundary is defined '\Xlatinoceras by the FO of the ammonite devonense (Wright & Kennedy 1991; Bengtsonlgg6). Several studies performed on planktonic foraminifers (Eicher & Diner 1985; Premoli Silva Er Sliter 1994, 1999; Bralower et aL. 1,995; Bengtson 1996) pointed out that the Ceno- manian/Turonian boundary lies between the LO of the gents Rotalipora and the FO of Hebetoglobotruncana belaetica. The FO of the nannofossil Q. gartneri ts Acknoledgemen s. I am grateful to Elisabetta Erba and Isabella recorded everywhere in the interval between the extinc- Prernoli Silva for stimulating discussions regarding microfossils and tion of the rotaliporids and the FO of H. heLvetica (e.g. biostratigraphy. I would lìke to thank Prof. K. Von Salis, Prof. S. Mo- nechi and Prof. M. Gaetani for reviening the manuscript and for their Perch-Nieisen 1983; \fatkins 1986; lfatkins et al. 1.996t helpful comments. This work was supported by grants MURST n' Bengtson et aI. 1996).Indeed, the FO of Q. gartneri may 99A1152971 001 and MIUR-SAUS n. 2001048975 001 to I. Premoli be used to approximate the Cenomanian/Turonian Sih.a. F. Tremolada

REFERENCES

Al Rifay I., Varol O., Lemone D. (1990) - Middle to late Albian Terra Not,a,3: 414-422, Oxford. biostratigraohv of the Cuchillo Formation from Sierra Cresta S., Monechi S., Parisi G. (1989) - Stratigrafia del Meso- de Sapellò, Mexico. Newsletters on Stratigraphy, 21 1,87- zoico e del Cenozoico nell'area Umbro-Marchigiana luu, úerlrn-)tuttgxrl. (Mesozoic-Cenozoic stratigraphy in the Umbria- Alr.arez \M, Arthur M.A., Fischer A.G., Lowrie'ff, Napoleone Marche area). Memorie Descrittice della Carta Geologica G., Premoli Silva I., Roggentheim \ilM. (1977) - Upper d'Italia, 39: 1-185, Roma. Cretaceous-Paleocene magnetic stratigraphy at Gubbio, Eicher D.L., Diner R. (1985) - Foraminifera as indicators of Italy. Type section for the Late Cretaceous-Paleocene water mass in the Cretaceous Greenhorn sea, \festern geomagnetic reversal time scale. Geol. Soc. Am. Bull., Interior. In Pratt L.M., Kauffman, E.G., Zelt F. (eds) 88:383-389, Boulder. Fine-grained deposits and biofacies of the Cretaceous Arthur M.A (1979) - Sedimentologic and geochemical studies \íestern Interior: evidence of cyclic sedimentary of Cretaceous and Paleogene pelagic sedimentary processes. Soctety of Economic Paleontologists and Min- rocks: the Gubbio sequence, Pt. 1, PhD Dissertation, eralogists, Midyear Field Trip Guidebook, 4: 60-71,Tu\sa. Univ of Princeton, 1-102. Erba E. (19S8) - Aptian-Albian calcareous nannofossil bios- Arthur M.A, Fischer A,.G. (1977) - Upper Cretaceous-Pale- tratigraohv'- _' b'.'r_'/ of.'_ the'_'- Scisti a Fucoidi cored at Piobbico ocene magnetic stratigraphy at Gubbio, Italy. Lithos- (Central Italv). Àlz. It. Paleont. Strat., 97: 455-483' tratigraphy and sedimentology. Geol. Soc. Am. Bull., Milano. \MV, 88:367-371, Boulder. Erba E., Premoli Silva I., \Vilson PA., Pringle M.S., Sliter Bellanca A., Erba E., Neri R., Premoli Silva I., Sprovieri M., Watkins D.K., Arnaud Vanneau A., Bralower T.J., Budd Tremolada F., Verga D. (in press) -Biostratigraphic and A.F., Camoin G.F., Masse J., Mutterlose J. & Sager \l\[ geochemical events in organic-rich pelagic sedin-rents (1995) - Synthesis of stratigraphies from shallow-water through the Early Aptian "Livello Selli", Northwestern sequences at Sites 871 through 8/9 in the western Pacif-

Sicrly. Pala e o ge o gr. Pala e o clim. Palae c o 1., Ams terdam. ic Ocean (Leg 1aa). ODP Scienufic Resuhs Leg 144, Bengtson P (1996) - The Turonian stage and substage bound- 144: 873-885, College Station TX. xies. Bulletin Institut Royal des Sciences Naturelles de Erba E., Channell J.E.T., Claps M., Jones C., Larson R.L., B elgique, 6: 69-81, Bruxelles. Opdyke 8., Premoli Silva I., Riva A., Salvini G., Torri- Bown PR., Rutledge D.C., Crux J.A., Gallagher L.T. (1998) - celli S. (1999) - Integrated stratigraphy of the Cismon Lower Cretaceous. In P R. Bown (ed.), Calcareous Apticore (Southern A1ps, Italy): A "reference section" Nannofossil Biostratigraphy, 86-131, Kluwer Academic for the Barremian-Aptian interval at low latitudes. /. Publishers, London. Foraminferal Res., 29 : 37 1 -392, Lawrence. Bralower T.J. (1988) - Calacreous nannofossil biostratigraphy Gale A.S., Kennedy'WJ., Burnett J.A., Caron M., Kidd B.E. and assemblages of the Cenomanian-Turonian bound- (1996) - The Late Albian to Earll' Cenomanian at Mont ary interval: implications for rhe origin ol oceanic anox- Risou, near Rosans (Dròme, SE France): an integrated

ia. Pale o c e an o gdp hy, 3 : 27 5 -3 1 6, Washin gton D. C. study (ammonites, inoceramids, planktonic Bralower T.J., Leckie R.M., Sliter \MV, Thierstein H.R. (19e5) foraminifera, nannofossils, oxygen and carbon iso- - An integrated Cretaceous microfossil biostratigraphy. topes). Cretaceous Researcb, 17: 515-6A6, London. \MA. In Berggren, Kent D.V, Aubry M.P, Hardenbol J. Gardin S., Del Panta F., Monechi S., Pozzi M. (2001) - A (eds.), Geochronology, tirne scales and global strati- tethyan reference section for the Campanian and Maas- graphic correlation. SEPM Special Publication, 54: 65- trichtian stages: the Bottaccione section (Central Italy). 79, Tulsa. Review of the data and new calcareous nannofossil Bralower T.J., Bergen J.A. (1998) - Cenomanian-Santonian cal- results. In G.S. Odin (ed.), The boundary between the careous nannofossil biostrrtigraphy of a transect of Crmpanian and the Maastrichtian stages: characterisa- cores drilled across the \(estern Interior Seawav. In tion and correlation from Tercis-les-bains to Europe Paleontologt and ""*.'b^*r'_/Stratigraohv "'_-and Paleoenvironments- of the Cretaceous and other continents. Deoelopments in \(estern Interior Seaway. SEPM Concepts in Sedimen- Stratigraphy, 19: 820-833, Elsevier, Amsterdam. tology and Paleontoìogy. 1r; i9-77, Tulse. Gradstein F.M., Agterberg F.P, OSg J.G., Hardenbol J., Van Bréhéret J.G., Caron M., Delamette M. (i986) - Niveaux rich- Veen P, Thierry J., Huang Z. (1995) - A Triassic, Juras- \W4., es en X{atierè organique dans l'Albien Vocontienne; sic and Cretaceous Time Scale. In Berggren Kent Quelques Caractères du Paleoènvironnement; Essaì D.V, Aubry M.P, HardenbolJ. (eds.), Geochronology, d'interpretation génétique. Documents Bureau Reserches time scales and global stratigraphic correlation. SEPM Géologiclues et Minières, 1 1O: 1'11-191, Lyon. Special Publication, 54: 95-128, Tulsa. Burnett J.A. (1998) - Upper Cretaceous. In PR.Bown (ed.), Hart M., Amedro F., Owen H.G. (1996) - The Albian stage Calcareous Nannofossil Biostratigraphn 13L199, and substage boundaries. Bulletin Institwt Royal des Sci- Kluwer Academic Publishers, London. ences Naturelles de Belgique, 6: 45-57, BruxelÌes. Corfield R.M., Cartlidge J.E., Premoli Silva I., Housle,v R'4. Jenkyns H.C., Gale A.S., Corfield R.M. (1991) - Carbon- and (\991) - Oxygen and carbon isotope stratigraphv of the oxygen-isotope stratigraphy of the English Chalk and Paleogene and Cretaceous limestones in the Bottac- Italian Scaglia and its palaeoclimatic significance. Geol. cione and Contessa Highwal' sections, Umbrir. Italy. Mag., 131: 1-31, Cambridge. C a lcar e o u s n an n ofo s s il b t o strati graphy 451

Kennedy VJ., Gale A.S., Bown PR., Caron M., Davey' R.J., togrtlphia Italica, 82: 1-85, Pisa. Grocke D., \fray D.S. (2000) - Integrated srrarigraph)r Premoli Silva L, Sliter \MV (.1999) - Cretaceous Paleoceanog- across the Aptian-Albian boundary in the Marnes raphl': Evidence from planktonic foraminiferal evolu- Bleues, at the Col de Pre-Guittard, Arnaycn (Dròme), tion. In Barrera E., Johnson C.C. (eds.), The evolution and at tartonne (Alpes-de-Haute-Provence), France: a of Cretaceous Ocean/Climatic System. Geological candidate Global Boundrrl- Stratotvpe Section and Society of America Special Paper, 332: 301-328, Boul- Boundary Point for the base or the Albian Stage. Crera- der. CeOUS /ti >Y l-,/lU, LOndOn. Renard M. (1986) - Pelagic carbonate chemostratigr.rphy (Sr, ^eSeArCn, Lommerzheim A.J., HambachU. (1992) - Cephalopod- and Mg, ''O, "C). Mar. Micropaleont.,IA: 117-164, Amster- magnerosrrrrigraphy of the Campanian of the Muen- dam. sterland Basin, N\W German,v. Cretaceous Symposium Renz O. (1936) - Stratigraphische und mikropalaeontologische A bstra crs, 47-50, H:rmburg. lJntersuchung der Scaglia (Obere Kreide-Tertiar) im Lowrie \(, Alvarez \(, Napoleone G., Perch-Nielsen K., Pre- zentralen Apennin. EcÌ. Geol. He/2t.,42:596-617, Basel. moÌi Silva L, Toumarkine M. (1982) - Paleogene mag- Roth PH. (1978) - Creraceous Nannoplankton Biostratigra- netic stratigrrphy in Umbrian pelagic carbonare rocks: ph,v and Oceanography of the Norrhwestern Atlantic the Contessa se*ions. Geol. Soc. Am. Bull,93 114-132, Ocean. In Benson \ME., Sheridan R.E. et aL. Initial Boulder. Report DSDP Leg 44, 44:731.-759, Y/ashington D.C. Luciani V & Cobianchi M. (1999) - The BonarelÌi Ler.el and Roth PH., Krumbach K.R. (19S6) - Middle Cretaceous cal- other black shales in the Cenomanian-Turonian of the careous nannofossil biogeography and preservarion in northeastern Dolomites (Italy) : calcareous nannofossil the Atlantic and Indian oceans: implications for paleo- and foraminiferal dara. Cretaceous Research, 2A: l35- ceanography. Mar. Micropaleont., 1A: n5-266, Amster- 167, London. dam. Luterbacher H.P, Premoli Silva L (1962) - Note preliminaire Salaj J. (1980) - Microbiostratigraphie du Crétacé et du sur une revision du profil de Gubbio, Italie. Rizt. It. Pale- Paléogène de 1a Tunisie septentrionale et orientale ont Strat.,68: 253-288, Milano. (H1'postratotypes tunisien s). Geol. Ustao Dionyza

Mohler H.P (1966) - Stratigraphische lJntersuchungen in den Stura, 1, -23 8, Bratislava. Giswiler Klippen (Prealpes Medianes) und ihrer hel- Salaj J. (19S4) - Bóundaries of Upper Cretaceous hypostrato- vetisch-ultrahelvetischen Unterlage. Beitr. Geologisclce types at the profile Djebel Fguria Sal.ah,Trnisia. Bull. Karte Schweiz, 129:15-84, Bern. Geol. Soc. Denmark, 33: 1.99-2A1, Copenhagen. Monechi S. (1981) - Aptian-Cenomanian calcareous nanno- Sissingh W. (1977) - Biostratigraphy of Cretaceous calcareous plankton from some secrions in the Umbria-Marche nannoplankton. Geol. frIijnb., 56: 37 -65, Amsterdam. Apennine. Ria. It. Paleont. Srat.,87: 193-226, Milano. Stoll H.M., Schrag D.P (2000) - High Resolution Stable Iso- Monechi S., Thierstein H.R. (1985) - Late Cretaceous-Eocene tope records from the Upper Cretaceous of Italy and nannofossil and magnetostratigraphic correlations near Spain: Glacial Episodes in a Greenhouse Planet? Geol. Gubbio, Ialy. Mar. Micropaleont., g: 419-44A, Amster- Soc. Am. Bull., 112:308-319, Boulder. dam. Thierstein H.R. (1976) - Mesozoic calcareous nannoplankton Napoleone G., Premoli Silr.a I, Heller F., Cheli P, Corezzi S., biostratigraphv of marine sediments. Mar. Micropale- Fischer A.G. (19S3) - Eocene magnetic stratigraphy at ont., 1.: 325-362, Amsterdam. Gubbio, Italy, and its implicrtions for Paleogene Tremolada F., Erba E. eAA4 - Morphometric analysis of Apt- geochronology. Geol. Soc. Am. Bull.,94:181-191, Boul- ian Assipetra infracreracea and Rucinolithus terebro- der. dentarius nannoliths: Implications for taxonomv. bios- Paul C.R.C., Lamolda M.A., Mitchell S.F., Vaziri M.R., Goros- tratigraPh)r and paleoceanography Mar. Micropaleont., tidi A., Marshall J.D. (1999) - The Cenomanian-Turon- 44: 77-92, Amsterdam. ian boundary at Eastbourne (Sussex, UK): A proposed Tròger K.A., Kennedy \flJ. (1996) - The Cenomanirn stage. European reference secrion. Pa/eogeogr. Paleoclim. Bulletin Institut Royal des Sciences Naturelles de Bel- PaÌaecol., 150: 8J- I 2 l, Amsrerdarn. grque, 6: 5/-69, Bruxelìes. Perch-Nielsen K. (1983) - Recognition of Cretaceous sta!ìe Varol O.(1992) - Taxonomic revision of the Polycy- boundaries by means of nannofossils. In Birkelund T., clolithaceae and its contribution ro Cretaceous bios- Bromley R., Christensen WK., Hàkansson E., Surlyk f. trarigraphy. Ne.,Dsletters on Stratigraphy, 27: 93-127, (eds.) Symposium on Cretaceous Stage Boundaries, B e rlin-Stutt gart. Abstracts, 1 52-156, Copenhagen. \X/right C.\XI, Kennedy \fJ. (t931) - The Ammonoidea of the Perch-Nielsen K. (1985) - Mesozoic calcareous nannofossils. Plenus Marls and the Middle Chalk. Palaeontographical In Bolli H.M., Saunders J.B., Perch-Nielsen K. (eds.) - Society Publication, 560: 1-148, London. \Watkins Plankton Stratigraphv, 329-126, Carnbridge University D.K. (1986) - Calcareous nannofossil paleoceanogra- press, Cambridge. phy of the Cretaceous Greenhorn Sea. Geol. Soc. Am. Premoli SilvaI. (1977) - Upper Cretaceous-Paleocene magne- B ull., 97 : 1239 -1219, Boulder. \il/atkins tic stratigraphy at Gubbio, Ital,v. IL Biostratigraphy D.K., \íise S.\M, Pospichal J.J., Crux I. 0996) - Geol. Soc. Am. Bull.,88:371-374, Boulder. Upper Cretaceous calcareous nannofossil biostratigra- Premoli Silva I., Sliter lilV (1994) - Creraceous planktonic ph)'and paleoceanography of the Southern Ocean. In foraminiferal biostratigraphy and evolutionary trends Moguilevsk;' A., \X/hatley R. (eds.) Microfossils and from the Bottaccione secrion, Gubbio, Italy. Palaeon* Oceanic Environmenrs, 355-381, Aberystwyth. F. hemoLada

:: e4 É, 8""",=a#E E,r,^.?e? é *-É" ; ,EEaE,E*

E E ; É EÉ=ltzEf'#É;: ];azitZÉ+È;' ÉÉlliÉeÉse .É=zÉE,€EÈ 3tiÈE :i, ;ù r Éi À;ioa>ouji>dÈ 4e>>> Là>Àzi <ùd<< údaoa ; RRR RR RR AARR'NiciddÀadFdoiNùro!ciNiú> RRR R RR RR RR AAR RR R RRR RR RR RAARF RRR R R R RR R

R RR RRRR R'* ÀCF RRR R RR R LO R. irresularis RR R R ÀCRR RRR R RR RR R R RAAR RRR RR RR R RRR RRR RR R AARR RR R R RR R RRRR R ACRR R R RR R R RR ACRR RRR R RR R RR R RR RR AARR R RR RR RR R AARR R R R RR F R R R RR ACRR R R FR RR R R R R R R AA RR R R R R R R RRR RR AC F RR R R R R RR RR R RR R ÀC C R RR RRR R R R R R RRAC F R R R RR RR RR R R RRR R AA F R R R RRR R R RR R R RR RR RR RRR R RR RR R RR R R R RRR R R RR R R R RR RRRR RR RR RR R R R FRRR R RR R RR R R RR R R AA F FRR R R RR RR R R RACF R RR RR R R RRR R R ACR RFRR R R RR R RR R R AAFR R RR RR R RR RR F R ACF RR R RR RR R R RR AAFR R R RRR R RR RR R RRAARR R RR R R RR RRR F R ACR RR R R R R R R AAFR R FRRR R

R RR R ACRR R RRR R R R RR R RR RRAAFR R RR R R R RR R R RR R AARR RFRR R R R RR R

R RR R ACR RR R RRR RR R R RAAFR R FR R R R R RR R R R R RR R R AAFR RR R RRR RR R R R ACR FR R RR R RR RR AAFR R R RR RRRR R R AAF RR RR RR R RRAAR R F R R R R R R R AAFR R RR RR RR R R ÀAR R F RR

RR R ACFR RR RR RR RR R AAFR FRR

FR R ÀC R R FRRR RR R RRR AA R RR R RRR R AC R RR RR RR R RRRAC R RRFRR RR R R RR R AA R RRR RRR RRR R R AA RR RR RR R R R RAC R R RR RR RR R RR RR R R RRRR R R AC RR RRR R R R FRR F RR RR R R R RR R AC RR R RR R R R

RR R AAR RRR C RR R R AARR R RR R C RR RR R R R AAFR R RR R R RRR R AA F RRRR RRR C R

R R RR CRR RR R R C RRR R AFR R RRR R R RR C RRR R AFR R RR R F RR R RR ARR R RRR R RR R R R RR R ,R CFR RR R R R RRR R RR AR R RR R R R R RR R RR ARR RRR RR R R c RR RR AFR R C R RRRR RR AF RR R C RR RRR AF R c R RRR CR c R RRR ARR R R RRR R C RR

R ÀARF RRR R R

RRR R AARR R RRRR R ,R:R R RRR RRACR RRR RR C R R RRRR RRACRR R RRR RRRR

RRR R AAR LO A. infracr€hc€a ts RR R R R AAR C RR R RRR R RRACR R RRR R RRAAR RR RRR R ACR C RR RR R CRR RRRR F R RR R R RR RRRR R F RR RR R F R RRR R RRR RRRR RR RRRR CR R R RRR RR CR

Appendir 1. Distribution chart of calcareous nannofossils detected at Bottaccione from the Upper Aptìan to the Upper Albian C alcar e o w s n ann ofo s s il b i o stratigrap hy 453

:É*.+ 3 ;4 z F 2 :- E_ E =".8t î 9 " a ò5 d j: H ; E :ii íi : ! ÉÌ i i Ei* i 5! eii i i *: i ! : : : : :È: ssi :i:i É Ei::::;iiii:3:3i= RRRR AARR RR AARR R RRR RR RR R ACRF RR R RR R RR RR ACRR RR R RR R ACRR R RRR R RRR AFRR RR RR RR R ACRR RR R R RRR RR ACRR RRR R R RR R R AFRR RRR R R R RR RR ACRR R RRR R RRR AARR RRR R IR AARR RR R R R R R R RR R AARR RR R R R R RR R R RRRR RR AARR RR R R R RRRR R AARR R RR R R R R RRRR AA R R RR RRRR RR RR RR R R ACRR RR RR R RR RR ACRR RR R RR RR R T RR R ACRR RR R RR R R RRRR R R ARRF RR R R RR RRR R RRRRRR R A TRF RR R R RR RR RRRR R ACRF RR R R R R RRRR R RR ACRF RR R RR RR R R RR R RR ACRR RRR R B RR R RR R R ACRR RR R R RRR RRRR R R ACRR RR R R RR R RRRRR RRR AARR RR R RR RR RR R RR ACRR RR R RR R AFRR R RR R RRR RR RN RR RRR ACRF RRR R R R RR R RR R ACRR RR R R R RR RR ACRR RR ACRF RR z RR RR R R R ACRR RR R z RRRR R R ACRR RRR RR R R R : RRR R AARR RR R RR z R RR RR AARR RRR R R RRRR R R ARRF RRR R R RR R RR R AFRC RR R RR RRR RRR R ACRR RRR R RR RR R R RR AARR RR R RR RR RRRR R AARR RR R RR RR RR R R R ACFR R RR R RRRR R RR RR R ACRR RR R R RRR R RR ACRF RR R R RR RR R R AFRR RR RR RR R R R ARRC RR R R R RRRR R ARRF RR R RR RR R RR RRRR RR ARRF RR R RR RRRR RRR A RF RRR R R RR RR R AAFF RR R RRR R RR RR R R R AARF RR R RR RRR R R AARC RRR RR R RRR R AARC RR R R R

RR R R ACRR R R RR RR R RR R ACRR RRR R R R R R R RRRR R R ACRR RR R R R R R R R RR RR AARF RR R R R RRRRR R AARF R R R R R R R ACRF R R K R R R RR AFRC RRR R R RR R R R R R R AFRR R R RR RR RR R R AFRC R R R R RR ACRC RR RR R R RR R R R ACRC R RR R RR R RRR R R RRACRF R R R R RR R R R ACFC R R R RR RR RRR R AARC RR RR R R R R RR R R R RR R ACRF R R R RRR R RRR RAARF RR R R R R R R R R R ACRC RRR R R R R R R R R R R ACRC R R R RR RR R RRR RR R ACRF R R R RRRR R R R ACRC R R R R R R R R R R R RR R R RR ACRC R R R R R R R R ACFR R R R R R R R R R R R R ACRC R R RR R R R RRRR.RF R R ACRC R R R R R R RR RR R R R ACRC R R R RN R R R ACRC R R R RRRR R R R AAFR RRR R R R RR R R R R RRR AART RR R R R R R R R R R ACRC RR R R R R RR R RRR ACRR RR R R R R RR R R RR R AAFC RR R R R R R RR R R RAARC RRR RR RR R RR R R R R R RAARC RR R R R R

Appendir 2. Range chart of calcareous nannofossils detected at Bottaccione from the Upper Albìan to the Upper Cenomanian 454 F. Tremolada

s?acg CENOMANlAN

SiXPLE

Mtît&

urx*xrafr UFFF !l u F*u a ,, , 7U r*u*ru*au*rFa* É*vuu* 9frarua 7 F *F FV"F* C. ffig.Rlii t. tufrcìff.1iì -7a& ,u1.aFfrtÉ? rlFF - *A t !F a *F I ,tu F

t>>>>> >?, >>>>>r>rr> îla a 1Ò î ^ i î î r:aFF--Artrrrr xÉ** E*É F

FF?F** ?T*'V'E UÉ X* F FÉF

L I

*t u * &

C. dispnr

i g- iigndt

Ndnn6tr!s clrrsirii

>FF

* * FVU Mi.úli st.

K. mrgnilìcù! Eplùbùs:p.

Q. gì€nrÉ!ft Cóslliù'on sp.

F E; lÉ tcE tEr 3 ! L

Appendix 3. Range chart of calcareous nannofossils detected at Bottaccione from the Upper Cenomanian to the Upper Turonian' C alcar e o u s nann ofo s s il b i o strati grap hy 455

SÎACE

SAMPLE

METER

Eel

Appendix'1. Range chart of calcareous nannofossils detected at Bottaccione from the Upper Turonian to Campanian.