Proposed G.S.S.P for the Basal Boundary of the Tithonian Stage

Rivista Italiane di Peleontolosi.t e Strrtisrafiiì vrrluntc I l0 nrr ì1t)-llS April 200.1

INTEGRATED STRATIGRAPHY FROM THE CONTRADA FORNAZZO SECTION, MONTE INICI, \TESTERN SICILY, ITALY: PROPOSED G.S.S.P FOR THE BASAL BOUNDARY OF THE TITHONIAN STAGE

GIULIO PAVIA', ROBERTO LANZA', FRANCESCA LOZAR', LUCA MARTIRE', FEDERICO OLORIZ'& ELENA ZANELLA

Receited Notenber 10, 2002 : Ltccepted Octobcr l ', 2003

\Wcstern Ke1, tcords: Sicilv, Uppcr Jurlssic, Tithonirn, G.S.S.P, le intcrprctazioni biostrltigr;rfiche. Lo sttrclio biostr;itigr;rfico si ò brseto integrlted stratigr;Ìphli anlnìonitcs, cirlcrrcous nennofossils, n.ì;ìgnero- strlle ricchc,tssoci.rzioni rrd rrnrnroniti, in cui il gene.rc H1'borroticeras è

st rrt i slaph\'. nccanrente rrìpprescntrìto con specie-inclice clel linritc Kimnrcriclsi:ìno- Titoni;rno. Sono strìtc riconosciute qu:rttr() bi()zor.re:rd:rrrlnoniti: tr.r Abstact. This paper de,rls u ith .r definition oi rhc lol'er bountl- queste, h biozonl basrle del 'fitoniano i'definita d;rll;r;rssoci;rz-ionc tli rrv strrtotvpc of the Tithonien Stage in the Upper Jurassic ,ucccssiou Hybonotit'ards sr. h),bonotunt e Hdplot-aras staszj,t-ii.l bioc'rcnti .r nln- of Montc ìnici, \ù/estern Sicilv The uppc'r nrember of the Rosso Anr- nofossili crlciìrci hiìnno pernresso di riconosccrc Ic Biozone l \i.ihiz/- rnonitico Fm. is 27 m thick and shorvs a t1-pical nodular-c,rlclreous neri c C. nexit',tnt, il cui limite è locllizzlto un poco sotto I'inizio dcl lithofacies; its lou'er beds have been slnrpled îor biostratigr;rphic ancl Titonilno. ll rccorcl p;rleonr;rttnetico prcscntir un;r polarità norÌì]rìle ncllir p;rleonr:runetic purposes. Though thc succession is effectcd bv hish Biozon;r a S. dara-irti/\l a/bertinunt c unil p()liìrità invcrs,r diffr-rs:r ncllc stratigrxphic condensrrtion, the lesulting hirtuses hive been shorvn to Biozone t H. bachcri c H. hl,bonotuttr. Sono strrti riconosciuti trL'cvcnti be belol' biochronologica,l resolution ;rnd rhus do not hirrder .inv bio- nrinori dì polaritì nornrale, nel pìir rntico dci clu.rli c:rcìe il limite inic- strrtiqrrphic clc'iinition. The biostratigrlphic anrll'sis h,rs been trased riore dcl Titoni,rno. l.c,rnllisi nrulticlisciulinari condottc nellrr sczionc on the rich ;rtnnronite assenrbl,rges in u,hich thc conrmon genus Hr,- di Contrede lìrrnlzz-o si integrano nel tlcfinire il linrite infcriorc rlel- bonoticeras is the inder-key for ch;rr;rcte'rizing the Kinrnreridsian-Ti- l;r Biozon,r a H. hy'bonotunl ;rll,r b.rsc clello str;rto ll0, che viene quincli thonian bound;rrr,. Four anrnronite biozones hrve been idcntiiiccll rhe consideriìto conre possibile G.S.S.Il dcl I'i;rno Titoni;rno. basal Tithonirn one is defined bv thc-,isserlblrrg,e of H1,l2s11s71ccr,r.s sr. hybonotum ;.nd Haplocerrts stdsz,)tcii. Thc recorded calcareous nrrnno- îossil bioevents ;rllow recognition of the V. stradneri a,nd, C. nexicatt,t Introduction Zones, rvhose bound,rrv is located ;i little belos, the identified Titho- nian los'er boundarl-. The paleonrruneric record shos's nornrrrl polaritv In the lirst dec,rdes the Tithoni:rn Vorking Group in the S. dar-,;'ini/V albertinunt Zone ,rnd nrrìnlv reversc pol,rritv in the of the International Subcon.rr.nission on Jurirssic Stratigra- H. becberi tntl H. h)'bonotutn Zones, l,ith three nrinor nornrrl polrr- phy (I.S.J.S.) h,rs been looking for a section which could ity intenals; the lorver boundarv of the Tithonian falls in the olclest ,rf these intervals. The intesreted multidisciplìnar')'srrrrigraphic infornr.r- serve as the Global Stratotype Section :ìnd Point (G.S.S.P: tion sathered fronr the Contr;rdl Fornrzzo section defincs thc lower Rem:rne er al. 1996) of the Titl.ror.rirn Stage (Olóriz Ec bound;rrl' of the H. bl,bonotunt Zone rrt the b;rse of Bed I 10, and sup- Schweisert 2001). Some propos:rls have been alre:rdy dis- plies elenrents of chrono-correlltion sufficierrt reg;rrd to this scction cussed which are b,rsed on the Anrrronite St:rndard Bio- xs i1 possible G.S.S.P of the Tithoniirn Strrsc. zonation established for the SuburediterrrÌnean Provincc

Ri.ttsunto. Questo lai.oro rigu.rrcl.r h possibilc definizione clcllo (Schr.veiuert 2000). Nevertheless, the spreirdins centres stratotipo dcl linrite inferiorc del Piano Tironi;rno nel Giur.rssico Su- of mirny Jurassic rnrrine biotir point to the Mediterrinc- periore di Montc Inici, in Sicilia Occidentlle. Il nrenrbro superiorc dcl an Province, whose position within the Tethvan Realn.r Rosso Anrnronitico è potente 27 nretri c prescnr;l una tìpic;r frcics crl- fostered colonisrrtion of the south Europe:rn shelvcs. It careo-nodul;rrc; gli strlti blsrrli sono strrti crrrnpionati per:rn.rlìsi bio- follows that d:'rtar Mediterrrìnern :Ìrerl hrve hiuh po- stratigr;rfichc c plleouraunetiche. Sebbenc ll successìonc presenti Iorte from condensirzione strrtigrafic;r, le hcune'individuatc rìsultano averc cstcn- tential as :1 basis for chonostr:rtiuraphic correl:rtion, lvhich sione inferiore.rlll risoluzione biocronokrgic;ì e quindi non influenzrno is the nrost importarnt criterion for selc'cting a bound-

I Dip;rrtinrento di Scienze dell:r Terrl, r'ir.t Accrrder.uia dcllc Scicnzc 5, 10123 Torino, It,rlr E-nr.ril: giulio.p.rvi.r(r urrito.it 2 Dep.rrt.rrrrcrr ro dc Esrrrr iqrrrii.r l Paleontología, Facultltl dc Cicncils, Ar'. l;uenrcnueva s/n. llÌ002 Cr;rn;rcl;r. Spr.rir.r. F--m;ril: floriz(rr ugr.e s ll0 G. Pat'id, R. Ldnztl, F. Loz,tr, L.,llartirt', I:. Olóriz Et L. ZaneÌl,t

The oltl lìorn.rzzo (ìLl.ìrr\' ()n thc northcrn siclc of Monte Inici; the servicc ro.rd is visiblc.rt.rlrout 700 rr of rrltitude. (strrr) Loc.rtion of thc Kirrnrericlgi.rn to Tithonirrn stucliccl wlrere.ts thc olcì s incling rorrl clinrbs thc ccntcr of the slopc. scct;on, rrlong thc scrvicc ro,rcl oi Contr.rclrr Ijorn;rzzo. Vics'tronr Contrrrcl;t Iìr.rginesi. Thc rstelisli nliìrlis thc outcrop clcscribcd in thc rcrr.

rry stratotype. At present, no proposlls on Meditcrrl- tenr in Septen.rber 2002 (Martirc c\ P;rvir.r 2AA4. ncan successions have bccrr forrl,rliz-ed for the Tithoni:rn In the geodvnlnric scttins, Montc' Inici rcpresents Stage; the Sicilian Uppcr Jurassic is pronrisins for this a structurirl ur.rit u,itl.rin the Mirshrebi,rn Chairr (Catalirno PurPose. et:11.2002, r.tnd rcf. therein). Its Jur:rssic succession is The scction of Contr:rdl Forn^zzo, on the we st- tl,picll oI the Tr,rpancse Donlitin, a carbonatc platfornr crn slope of Morrte Inici, cxposes the Kirlmeridgian/Ti- which subsided in thc middlc [xyl1, Jr-rr;rssic first as a pc- thonian bour.rdarv interr',r1. The beds irre charactcrized l,rgic srvcll, and cventuallv into birsin conditions in the by rich anlnlonite assenrblirses u,hich could supplv ba- Cret:rce ous. sic biostratisraphic inforrìriltion for the identification of In the Monte Inici nrorphotectonic ur.rit the whole that boundary. Actu:rlly, thc uppermost Jurrrssic of Sicilv Juri'rssic successiou crops out, :ìnd is conlposed of tq,o is fanrous through the rnrnronite nlonographs prodllced classic lithostratisrirphic conrplcxcs: (1) thc Inici Fnr., by Gemnrelllro in the ll-ttc rlineteenth centurv (see the hundreds oi metres thick, rcpresents the Upper Trias- rcvision editcd by Pavia & Creste 2002), and the conrri- sic to l,orver Jur,rssic cpicont;nenral carbonalte phtfornr; butions bi, Floridi,r (1931) irnd Christ (1960) rvith details (2) thc Rosso Anrr.nonitico Fnr., sor-r.rc tcns of uletres on Monte Inici fossil asscnlblilses. thick, reflects carbonate sedinrcntrtion in a pelirr:ic plat- In addition to thrt. the section ,rlso bears rrn inrcr- fornr condition thrÌt is biochronologicalll'proved to have est;ng recorcl of c,rlc,rreons nannofossils ;rnd cle,rr p,rlco- bcen ,rctive ironr Toirrcian to Middle Tithoniln, at least nlasnct;c sigrr:rls. rr Such conlbin:ltiolt of stratiuraphic (Di Stcfano 2002). At the top, tl.re red-nodul,rr linrestones ,rppeirrs r,erv tools to be frrl'our,rble to proposing the pilss to the thick l-rrttirrusrr Fnr., nririnlv Eirrlv Cret,rceous section iìs the rcfcrence for the Tithonirrrr basal bound- in rrgc. In the rvcstcrn sectors of Monte Ir.rici tl.re Rosso ary rvithin thc Mcditerrirrrc:rrr Provincc in .ù7cste rn Tcthvs, Ar-nrnonitico Fnr. cirr.r be subclivicle d into thrcc rrer.nbers if not even irs thc G.S.S.P of this Strse . (Fic. 3): rrrrssive-crrlc:rreous i11 tl.rc Iower pilrt (Rosso Anl- t.non itico I nferiorc: RAI), urarlr'-siliccor-rs u,ith r,'rdiol,rr- itc-like beds in the nriddle (Rosso Anrnronitico Medio: The section of Contrada Fornazzo RAM), nodulrrr-c;rlc:1rc'oLrs in the r.rpper prrrt (Rosso Anl-

Thc outcrops of tl.re Fornazz-o scctor (Montirgrrir c1i Illorlitico Superiorc: RAS). Gilnnuzzo in Gemr-r'rell:rro 1878: Costiì l-îrga in Floridi,r The u,l.rolc lÌAS successior-r is exposcd in ir nlturirl 193 l, irnd Christ l96O) lrc locrrted on thc north\\'cstcrn olltcrop rrlong the qLlilrrv scrYicc ro:rd, rvhcre the ur:'rs- slope of Monte Inici, sonre 3 knr south-u'cstrv,rrds of Cirs- sive rccl-nodulirr lirncstones of RAI h,rd bccn exploited tellrurr.nrrre clcl Golfo (Fig. t). The best exposurcs rrrc in up to thc sixtics (\Ve ndt 196.1). ln p:rrticr,rlrrr-, the Kinr- thc old "nr,rrblc" qurrrv of Cor.rtrtrda Fonliì2.7-o ,rnd ,rlorrg nrericlgilr.r to Tithonilrr bcds ,rrc cxposed ;rt thc bend of thc service ro,rd le,rding to the qu:rrr\'(Fiu.2). The Iìor- thc ro:rd (200 nr rrltitr.rdc) corre sponcìing to thc n.rorplro- nrlz-zo oLlrcrops \\.ere visitccl dr,rring onc of the ficÌd trips structurrrl crcst th;rt clcsccnds ironr Piz-zo clcllc Niviere of the 6' ' Internltional Svrrposir,rnr on thc Jur:'rssic Sys- to Contrldrl Fr,rgincsi. Upper Jwrassic succession of Monte Inici, W Sicill, 331

Lithostratigraphy at the Kimmeridgian/Tithonian boundary

The succession exposed in the upper part of the iL- I l-: composite section of Contrada Fornazzo consists of several levels which were described in detail by Martire | O LowerBerriasian & Pavia (2002). Here we restrict the attention to the - beds present at the very base of the RAS; their number- ing, from 93 upwards, continues from assigned I Y-=-= numbers a- to the other two members of the Rosso Ammonitico. In particular, Beds 93 to 132 were investigated in detail l-- with a multidisciplinary approach; they can be grouped into three levels which are here described from bottom to top (Figs. a, 5). !- O Upper Tithonian | - È<=< Level 1 (Beds 93-105:3.45 m) l-+ Nodular limestones with cherts in snrall nodules lnd ribbons. Thìs interval is easily weathered becruse of the thirr beddins, well de- I 1_ + veloped nodular structure irnd thick r.nlrly interbeds. Tivo clay beds,2-3 l4 '--..=!t{ cm thìck, are continuous ;rnd shol, the typicll pllsticity of bentonites; - X-ravs diffractorìretry indicîres l snrectire conrposition (Montaenino, [:= TI pers. conrm.), so theìr priur;rry origin ls lsh l;ryers is possible. t::li3- l---rr^tl I Level 2 (Beds 106-'123:5.85 m) I: I Conrp:rred ro the underlying interr';rl, thìs one bears no cherts lz=- I and is more nr:rssir,e and less easily rve;rthered, forming e small clìff - ---- ' recognizlble llso in the dìstance. Beds have different thickness lnd Il- -'- x-) Lower Tithonian - lithofacies. The nrost massive ones consist of incipientlv nodular to -l : .F Upper Kimmeridgian l-rs+ homogenous coarse grainstones rvith :rbundant Sdccocontd debris and subordinìte snrall peloids. Grains ;rre reorg:rnized in e firted, poorly ce- rr$ I nented fabric along dissolution seaÌrs. These Saccoconta-qr.rinstones | :=-=-?B I L_=-\B grrde unevenlv to finer graìned grainstones I'ith sclrce Srtccocomd and -t I ,rbundlnt spheric;.rl nricritic plrticles interpreted ls rlcliol:rrian molds. No true nodules cln be recosnìzed, ;rlthough local rlerging of s,;rvy dissolution seAnls cAn produce;r nodul;rr cffect. These beds may be referred to ;.rs the mlssive bioclastic facies. Other beds, usutrlly thinner, shorv the tvpical knobby;rspect of nodr"rlar linrestones, rvhere nodules l nd ulirtri\ are differently u,eath- Lower Kimmeridgian ered. They cln be referred to rs the intr;rcl;rstic nodular flcies oi Ceccl et al. (2001). T\vo kìnds of nodr,rles n;ry be recognìz-ed. Type 1: nodules shos. grldirtional boundlries and usr.rally r flet- tened ellipsoidal shlpe. They consist of p;rckstones to srainstoncs u,ith predonrinant S.tccocotTtLt;rnd subordin,tte peloids and Globocbaetae.Tl"te nratrix is typically recl, crossed b1'bundles of dissolution scer.ns, lnd is conrposed of S,tccocottt,t p;rckstones with a fitted flbric. These nodules fit the dcfinitìon of earll'diasenetic nodules oi Clari et al. (1984). Type 2: noclules h,rve more irregulirr, often spheroid sh,rpe lnd shlrp boundlrìes u,ith the nlrttrix. The), nr;rinly consist of fine grein-

l{ì Middle Oxfordian

Lithostratir:raphic log of thc Rosso Anrnronitico conrposrte section cropping out in thc Contr.rclrr l;ornlzz-o lrc':r (after M;rrtire ct ll. 2002). The vcrtic;rl b;rr indic;rtes rhe interr,;rl ;{, Middle callovian ? describecl in this rvork. 5r'rrrbols: B = bentonrte lrvcrs; I-ATT : I-;tttir.nusa Fornt;r- tionl RAI : Rosso Anrnrcrr.ritico Inferiorc'; MM : Rosso Ar.trmonitjco Mediol RAS : Rosso Anrnronitico Superiorc'. Amnronite:rnd cllpioncllicl icons refer ro lsscnrbhges stud- ieti for biostratigr;rphic purpose. il2 G. [7rtia, IL. Lattza, F. Lozar, L lltrtirc, F. Olririz Ei E. Zattclla

:ri pr()ccsses such rs e,rrlv ccnlentitti()n rrnd pressure dissolution. Sontc scclinrcnts rrcre intensclr.cellcntetl just belol thc sedinrcnt-\\.rtcr in- terl.rcc .rncl this inhibited rhc cffects oi conrp.rcrit,n (Clrri .\ Marrirc 199(r); rrtrrsivc becls wcrc protlucecl in this * rr'. N'hcre, on the conrrlrr., e,rrl'cc'rc.t.rti.n rr'.rs lcss intc.sc.rntl rifcct.,d.nlr. linrited p.rti.r.rs of bctls (norlules), rr trelt p.rrt ol tlre betl ri,;rs srill unlithified lt buri,rl deptirs r hcrc prcssurc clissoluti<,n processr\ st.rnctl. Ì:ittcd febrics,rnd tlissolution scJnrs \\.cre hencc'gcncr.rted giving rise to cl;rt.-rich, rec.l- clish linrtstoncs nrorc elsilv rvclthcred in outcropr, cnhancing noclul,rr- itr: I'.rrlv ccnrcntrtion is intlucecl [rv verv l.rrge iìlì]()unts rri sc;r rr.rrcr flol'irrs through thc porcs.rncl prccipitrrtirìg crlciurìl cf,rDonirre (e.s. Tr,rckcr N \\i'ight l99O). (lcrrrcnt.rtion h,rs been shorr.n ro be cffcctivc also in pcl,rgic sedi:rerrts.rt ol hLrndred or iì rh()us.urd nrctres, plor.icl- cd rh.rt currcnts arc strong cn0uglt tO "punlp" se.ì \\.iìter into the porcs (c.s. \lullins ct rl. l9tìO; Allouc l99O). Thc highcr thc pernre:rbilitv of thc sctlirrrcnt .rncl thc specd of currcnts, ,rncl thc longer thc proct,rs, thc Ilorc cfiecrile will bc cenrentrrion. The tops of pcn.lsir.ely cenrcnted becis.rrc liltclv to corrcsponcl ro hiiìruses cluring u,hich currcnrs wcrc ìcri\c.rnci rri!age rccl ccr.rrcnrr'rrion oi thc undcrlving scdinrcnts. The reg_ ulrr interberlditrs oi noclul.tr lncl rrr;rssivc bccls, clelrlv shol.n [ri, the l,'rr,r P.1rr r,l rlrt.RAS,,r,ul.l I't,irrr.,rprcrcrl in this Irght.r, th" rcrrlr oi.r cvclicitv in hvtlroclvn.rnric ler.cls lherc rhe lrorluhr beds represent r.n.rc c.rrir.ru.us serlinrentrrtion u.itlr only sclccti'e lithiîicatiorr s,hile nrrssive bcds, suclr.ts l06, lOg.rnd I I l, inrlicetc high enersr.rnd high setlìr.errtrtti.rr.tc clep.siti.nrtl c'cnrs frllori,cri b'non-clepositi.n.tl t Pirrrrlt r r('\uIr inq in P.,n.rsitc c(rìì(,rìt.ìti,rrì.

Ammonite biostratigraphy

Fossil assemblages Ccphalopod renlirins represent rhc sole nlacrofos- (ìlosc-up l;ig..{ - lieu ol. the lretls .rt thc p.rss.t*c Uppcr Kinr_ sils of thc lor.ver pirrt of the RAS. Anrmonites alre the mosr nrcritlgi.rrr ( l0l- 109) to 'ì'irhoni.rrr ( I lC- lll). Nrtur.rl out_ conlnlon fossils, whcreas belemnites occirsion;rlly rc:rch cr,rp enl.rrgccl lor prlrteontologic.tl srntpling. Hrrntnlcr on 5"1'. A dctriled sanrplins has been carr;cd out in levels I rirc hrs.rl irrrt ol llctl I lO ior sc.rle. ;ìnci 2; ir \\'rìs concentrired in the inrerval between Beds 95 ;rnd l2O fronr which nrore than 700 rrnlmonircs were il:lthcred bcd-br.'-bed. Thoush rhe sr:Ìre of presen.ation is ofte rr poor, 58 specics have bcen idcntificd of which the st.ncs r'ith.rbund,rrrt nricritic rrrii.l.rrirn rrr.lcìs.rrrtl sub.rurn.rre .r,rr nlost sisnif;canr (o(oDtLt\ lrclOitls rrrcl (ì/,brxlttL'tat. S0nrc .l thcsc :h.rrp-cclgctl Dt,cltrlcs are listed in Fig. 5. Ar.ltrnonite assenl- shor'.r slighth tlarkcr rirrr rh.rr corrcspontls to rhc nrincr'.rlizccr fiiling bllgcs ,rrc donrinated by Mediterr,rnean raxa; ;lnlon[ì phyl- ol nticroborirrqr: rhcv rre Prc-tlcposirion.rl rrotlulcs lsensu Clrri cr rl. loccrrtids So.ii'erb1,ssyr15 ur. lotTi rorirls nlore than 50,2, of l9fÌ{), i.e. tltcr'.rre irrtr.tchsrr crprosccl on rltc sc.r iloor, colonizctl br. thc rrsscnr blrrues. Conrpl enìentary taxi are aspidocer;rtids, cntlolithic org.'rnisrrrs .rntl c,rrtctl trr'.rLrthigtnic rrrincr.rls (l:c-\ln ,rriJc.1. haploccr:rtids :rnd perisphinctids; the conlrìlon senus Intcrpret.rtion oi 1\'pe-J rr,ttlulcs thrt bc.rr rrt, borings rrntl st.rinirru is H/- bottoticaras less obviot-ts; thel coLrltl b,,irrtr,rcl.rst. prorlucccl bv currcnt crosiorr of merirs a prccise biostrirtierirphic analvsis. senti-lithific.l rctlinrcrtrr, t,r br burrt,rr inq.rrrtl nririrrg ()i rc\tur.ìll\ c()tì- Anrnronites :rre gener:rllv pre served as calc:lreous in- trirstrr g ulltcllìcnlc(l 5r(linlcltts. tern:ìl nroLllds without shell rcnrains. Thev lre reDresented bv phr,rgnrocone s usu:rll\ u ith p.rrti.rl bodv ch.rmbc,r or l.*el J lBctls l-?+-ll:; J.{5 rrr.1 bv frrrsnrcnts of the lirst rvhorl reflcctir.rs biostratinoruic Altrrrr.rtions of rl.rssile .rnti rrotlul.tr linrcsrorres rs clescribt,tl in the untlcrl'ing intrn.rl, bur rith chcrt nt,tlul.'s c,,rcentr.rrcci irr srrrrc brerrk,rgc of the shell be fore burial. The size of fossils is bcds. ,Altcr.r O./O crrr rhick e.r.crctt trf,ct,.ì rìr()rf ()r lcss q()'.r1.()us varirrble; s()nte frilqnlenrs indicarc shell size up ro 2OO t\p()surc ol .tltcrn.trìons ol notiulrr.rn.l fl.rr.,r-rr,,tltrlrr linrcstoncs rr itlr nrnl. Horizonr;ìl posiriolls tre dontinînr, excepr for snr,rll- sprrst'pirrli chcrr rr,,.lules,rccur.'l-hc rr,tlrriri.n r, thc r'hitc rnicritic sizccl fossils rhat could havc been reorienred rvithin thc li:rertorrc, of rhc (lret.rccotrr l-rrrinrusr ì:rrr. t.rkes plrcc .rlrour J9 rrrc- substrittc tres .rb,,rr thc brsc ol rhc l{r\S. bv bioturbation or later bv the conrbined cffect of prcssurc solutior.r rncl conrpircrion. Pl.rstic defornra- ()n the brsis ol thc Jtscriprit,n.rb,,r'e. it.rppc.rrs rir.rt rlre I,,rrcr tion observed ir.r sonre specinlens depends on differe ntial p.trt ol the l.ì.AS 1er Ic.rrr lJctls l06 to l-ìl) consisr oi tr.rin-supp,rrteri conlprìction of the internal infilling of thc phr:runrocone lrnrt'st.rrcs rrltcrt rhc p'tv.rilirrg gr.rirrs .trc .\,ttcrttrt,t,t ir.rgrrrents.'l'his versLls bodv ch,rnrber. As ro the sr:ìtc of preservlrion, (l) nr'r' be irterprctcd rs tlrc lrsult .l .r rr inrr.* irrg cl lcct b' b.rr.rrr cur- 'l'he nlost intcrnal nror.rlds rerts. clill.erent l.rcics lrr.rssi'c [ri.cl.rsric t. ilrser rr.tlul.rr rrr.rrl' ilre covered bv ,rrgillirce ous coitt- litrcstones).Ìr-c c()rì\c(ìucrrrìr't,, bc rel.rtc.l rr.rinlv t,, posr-tlr.1r,,riti,,n- inss derivins fronr pressure-dissolution ;rt the boundary Upper Jurassic strcccssiort of Alotttc Initi, \\! Sic'ih, 333

::.:to 130 E È PÈ È È!i P È ;: t Èr * È ó€ i.ròÈ 9e3I ìi:ÈÈÈ=àÈ==. È 124 I ò ? :'Q 9: a,: = ò3 ÈaÈ:ÈÉ;ià i _ùÈì3ài:F 'lXX:or:ì-\9-uxeÉqòò.-s :rr - x; P;s tr : 127 :SR 9 È È d è Ì r 5ì : r€ EÈ;: F: : q;!. gig HàÈ È:àÈ. iG; à 3 : b óE b, i t i 9È 333 4: ? gi' I I è: F 3;tt S ;îÈ B 125 xÍì- gÈP33s+irl ò ì ì h ó ó 9 ò ò r rò : 4 4 4 ÈÈ ? obÈòòòH;XX 3; ssÈ É ù ù È 8g'"'" r r ; 3 3 3 ; 3 fr ; 3 U P P ò 3 gÈ gÈ!!s!! z 123 sE ::::::ia3È ! oi3 o o osss o ù o o o o o o o o o I HgÈÈÈÈ;EÈÈ ! ! !: 9 9 ! bb ! : ! ! : a : i : : a : : o ÈÈÉÈ ÈÈÈi:; -N 122 5òf tt:*Fe3Èòò òò SsSgs s àÌl ; t ; ; isiiiiÈÈi ÈÈ 121 I 120 I to 9l Qo z I ?t I so 1r8 tl z I tl I 117 îî I q! I - 116 tl o I îî I 115 tl =t- --.1-t- --.1- _-u É I qZ 114 tt LIJ ?l I QO tt PN tl Ès 111 't Èi = €x J 110 € r09

107 z r06 g

105 O o 104 É 142 uJ

101

100 ftU v óoxz É 9N I.JJ a: n OQ o- oo l

between the concretionary mould and the encasing sedi- Biozonation ment, (2) the texture of the calcareous infilling is thc Ar.rrmonite biostratieraphv rv"r. correlated with same that observed in surrounding nodules without irny the Standirrd Anrr.nonite Bio-Chronozones proposed for adoral discontinuitv (3) internal nroulds do not show anv the Mediterr-arrcan Province by C,rriou & H:rntzperguc mineralized crusts, truncation facets, erosion surfaces or (1997). Fr.rrthcr rcsults and/or reinterpretations by Sirrti biogenic encrustations. Such characteristics indicirte no (1993), Villirscnor et arl. (199.1, 2000), Schweigert et al. removal of rhese fossils from the embeddins sedinrent; (1996), Car:rcucl et al. (1998), Carircucl 8i Olóriz (1999), they can be defined as resedimented elenrents "coer':rl" Olóriz ct Villasenor (1999), Olóriz ct ,rl. (1999), as u,ell to the en.rbc'dding calcareous r.natrix (Ferníndez-López as unpublishcd c'lata from the Bctic Cordillera by Oloriz 1991; Pavia tr Martire 1997). 8l Sernl-Barqr.rero (in prouress), have rrlso been tlke n in- The only ammonites in which removal fronr thc to account. In upper Kin.rmeridsirn rrnd lorvcr Tithoniirn origintrl sedirnent has to be admitted, are the molds present four biozoncs h,rve been recogniz-ed (Fiu. 5). as reworked "pebbles" at the base of Beds 1A2,107,117, Mesosirnoceras ca't,ouri Zonc - This biozone is and upper 119. Nevertheless, in these cases also, trirces proved in Bcds 95 to 101 based orr the joint occllrrencc' of bioerosion, bioencrustation or Fe-Mn oxide coatings ol M esosintocaras risgo'i:iezsis and Psaudot;'aagertia tcatt - are missing; the only evidence of taphonomical reu'ork- tbotnphala fronr lavers just bclow the first occurrcncc ing is the broken internal moulds of single specinrens witl.r (FO) of thc scr.rus Hybottoticcras. Thc index-species ,M. slight displacement of the separirted parts ("uncoupling caaouri is known onlv fronr a singlc specinlen collccted moulds"). These fossils can thus be regarded as the result from a corre lirtcd section studiec'l in the irrea, in a layer of winnowing of early lithified shell infillings, for a pre- corresponding to Bed 96. sumably short tin-re and with no appreciable displacerrent Hybonoticcras becberi Zonc - This ranges fronr Bcd on the sea bottor.r.r after the first burial episode. 102 to Bcd 108. Although rvc rrrc:1wrrc rherc is no qc'n- 334 G. Pai:ia, R. Lanza, F. Lozar, L. Martire, F. Olóriz Ei E. Zanella

chapter. A sort of cyclicity in the lower p,rrt of the RAS n.ray be recognized with two superposed orders of cycles: a Bed I 12 a higher one, developed from bed tot to bed I 16, defined t: tt by the upward increasing thickness of massive beds, and la a lower cyclicity order, simply defined by alternation of t e nodular and massive beds. Texrural features and degree f-a . ::ll r. of cen.rentation allow interoretation of anv of the lower . r. .:t order, eiemertai, .y.l.r, *ith nodular f..i., .t the base

l(x) -100 5(x) 6(x) 7()() and massive facies at the top, as the result of an upward- T ('C) increase in hydrodynamic energy endinc with a hiatus. In (b) the lìght of this cyclostratigraphic oreanisation, it can be concluded that bed 109 represents the upper part of an elemental cycle starting with bed 107 and thus is to be Bed 1 15 referred to H. becberi Zone.

S em ifo rm i c era s darr.u i n i / V i rgat o s i rn o c erLl s d I b ert i - num Zone - Though the index-species are missins, the a record of a specimen of Virgatosìmoceras cf. uniforme, !r a coupled with an.rn-ronite assemblages lacking tn Hybono- al t ! r-irr ticeras ;.nd lareely don.rinated by haploceratids exclud- 0 | 0() l()() l{)0 -l()() 5(x) 6(x) 701) rng Haploceras verruciferum, have been used as evidence for the S. darruini/V alberti;tunt Zone. The biozone has been ranse 115 Bed 120; the Fig. 6 - Thcrnr,rl clenr,rsnctizrtion of the IRM conrponents. Svm- interpreted to from Bed to bols: clot : lo\\r-i squrre : internredi;rte-; dianrond = hifah- boundary with the underlyine H. hybonotwm Zone could coercivitv corìrponent. not be accurately placed.

Magnetostratigraphy eral consensus on this sLlbiect, just :rs in the Betic Cor- dillera (Olóriz & Serna-Barquero, in proeress) here the Sixty-five samples were cored from Beds 100 to H. beckeri Zone can be subdivided into three parts: lower 122 across the Kimmeridgian/Tithonian boundary in the part (Beds 1A2-104) characterized by the combined record Fornazzo section. Magnetic mineralogy w;rs investigated of H. cf. pressulunt and H. cf. verestoicun; middle part by isothermal remanence (IRM) acquisition curve and (Beds 105-106) bounded by the FO of H. becleeribelow thermal demagnetization of IRM components accord- and the FO of H. harpephorum and related forms above; ing to Lowrie (1990). In Beds 115 to 122, saturation is upper part (Beds 107-108) embracing the range of the approached at field value of 0.2 T and reached at 0.4 T. forms related to H. batpephorwm. The upper boundary Most of the IRM is carried by a low-coercivity compo- of the biozone cannot be accurately interpreted due to nent, which is completely erased after heating at 530-560 scarce ammonite record in Bed 109. 'C (Fig. 6). The intensity of the high- and intermediate- Hybonoticeras bybonotum Zone - In the lowermost coercivity con'ìponents is low and they are erased in the Tithonian, from Bed 110 to Bed 114, this biozone is es- same temperature range. Magnetite is thus the only fer- tablished by the range of the index-species, .É1. hybono- romagnetic mineral. From Bed I 14 downrvards, saturation tum,.and related forms such as H. robustum and Hybono- is not yet reached at field value of 1.6 T; the intensity of ticeras sp. "trapeciale"; Haploceras staszycii is a sisnificant the intern.rediate- and high-coercivity components is high oC. taxon and perisphinctids and haploceratids also sive use- and they persist up to 650 In these beds magnetite ful information. The upper part of the biozone (Bed 1 1a) occurs to€iether with variable amounts of hematite. is characterized by the onset of the senus Fontannesiella Both thermal and alternating field denraqnetization as also found in the Betic Cordillera (Olóriz 1978). The techniques were used to isolate nagnetization compo- lower boundary of the biozone, and thus of the Tithonian nents. Ten to twelve steps were done either from 120" Stage, seer.ns to be difficult to locate, due to absence of to 440-520'C or fron.r 4 to 100 mT. A low-temperature, sienificant ammonires in Bed 109. Nevertheless, though soft magnetization component is often present and erased documented by a single specir.nen of the index-species, after the first steps. At higher temperatures or fields, dif- the base of Bed 110 is certainly referable rc rhe H. hy- ferent magnetization components are isolated and three bonotum Zone. Bed 109 instead can be confidently re- groups of specimens can be recognized on the grounds ferred to the top of the H. becberi Zone on the basis of of their characteristics. the stratigrrrphical and sedimentological considerations - Group 1 (Fig. 7a). These specin-rens have two re- previously discussed at the end of the lithostratirraphy verse polarity masnetization components whose direc- Upper Jurassic successiott of Monte Inici, \Y! Sicily 335

zeo tîî---'t, a

! tuo \.t'r. .t aao / r\. ,) aao a

Scalc: l0 ' A/rn

Fig.Z-Zijderr'elddi.rqr.rnlsf

tions sliuhtly differ in declination. The first is defined The oldest interval is recorded in Beds 108 to lower 110, between 160'and 320o to 360'C, the second at higher at the boundary between the two zones, the second in temperatures. Bed I 1 1 and the youngest corresponds to a single speci- - Group 2 (Fie. Zb). These specimens have a nor- men in the lower part of Bed 115. From the upper part mal polarity, soft magnetization component, fully erased of Bed 115 upwards, the S. daruini/V albertinum Zone at peak field of 16 r.o 20 mT. At higher values, a reverse is characterized by normal polarity. The polarity succes- polarity component is isolated, stable up to 100 mT. sion at the Kimmeridgian/Tithonian boundary at Fornaz- - Group 3 (Fig. 7c). These specimens ha"'e interme- zo agrees with those from the Subbetic Zone of the Betic diate and high temperature components. The first is de- Cordiflera of southern Spain (Ogg et aL. 1984). The main fined in the ranse fron.r 160'to 280-320"C and character- new result is a greater detail at the boundary between the izedby reverse polarity. The second has normal polarity, H. becberi and H. hybonotum Zones, which is shown to appears above 320"C and is stable up to 480-r40'C. occur within a normal polarity interval. These results show that the magnetization history at the Fornazzo section is complex and it is not straight- forward to assess which component corresponds to the primary magnetization acquired when the rock formed. Moreover, the contributions of magnetite and hematite cannot be clearly separated, because the coercivity or blockine temperature spectra of the two components of the natural remnant magnetization often partially over- lap. We regard the characteristic component (ChRM) isolated at hiuh temperature or peak field values as the primary n'ìal]netiz.ation, both because it is the most stable and its direction is consistent with those found at other Ammonitico Rosso sites at Mount Inici and in the Tra- panese Domain (Channel et al. 1990, and ref. therein). The ChRM directions are shown in Fig. 8: the mean directions of the normal and reverse polarity group are respectively D : 25.4,I : 21.5 (n : 29, a.,.: 4.3") and D :211.7,I = -14.3 (n = 19, cr,,,= 4.9o). Other 9 specinrens yielded a definite polarity even if no reliable direction could be calculated. Comparison between paleomaenetic and palaeon- tological results (Fig. 9) shows that in the H. beckeri a,nd bybonotum Zones magnetic is re- H. the polarity mainly Fig. 8 - Equal-arel projection of tilt-corrected m:rgnetiziìtion direc- verse and alternates with three normal polarity intervals. tions. Full/opcn synrbols : positive/negative inclination. 336 G. Pat,ia, R. Lanza, F. Lozar, L. Martire, F. Olóriz &. E. ZanelLa

Fig.9 -Multidisciplinary stratigraphic schenre rvith correl;rted position oi the lorver boundary of the Tithoni;rn Stage. In the paleomrunetic column: left, stratigraphicel position of indì- vidual specimens; right, black/ white : norrrral/reverse polarity; crossed: not sampled.

Calcareous nannofossil record contrast, the structural features of C. mexicana minor and P. beckmannii are probably less affected by diagen- Calcareous nannofossil assen.rblages from 28 sam- esis and their diagnostic features are easily detected even spanning Kimmeridgian/Tithonian boundary ples the in poorly preserved material. have been studied (Beds 93-119). The assemblages are nrainly dominated by Watznaueria barnesae, W maniai- tae, W britartnica, Cyclagelospbaerd margerelii, Cy. raied- Integrated stratigraphy discussion mannii, Cy. deflandrei, Diazontatolithus lehmanii. Despite overall poor presen'ation of the n.raterial studied, and gen- Correlation with the marine anomaly M-sequence erally poor biostratirraphic resolution for this time inter- is not direct at Fornazzo, since the studied section cor- val (de Kaenel er al. 1996 Bown & Cooper 1998), three responds to a relatively short time span. The correlation calcareous nannofossil events have been recorded: the FO of palaeontoloeical findings with masnetic polarities does of Conusphaera rnexicana mittor in Bed 108 and the FOs agree with the literature data. The FOs of C. mexicana mi- of Parhabdolìtbus embergeri and oî Polycostella bekman- nor and P. beckmannii occur in normal polarity intervals nii rnBed 112. Two CN Zones (Vagalapilla stradneri and (Bralower et al. 1989) and the Virgatosimoceras albertinum Conuspbaera mexicatta Zones, Bralower et al. t989) and and Hybonoticeras becheri Zones respectively correspond two subzones (Hexapodorhabdus cuoillieri and P bech- to normal and reverse poiarity intervals, as obser-ved in the mannii subzones) are thus identified. It is noteworthy Carcabuey secrion (Ogg et al. 19s4). \ù7e therefore advance that for the first time these events are directly correlat- the hypothesis that the lower part of the Fornazzo sec- ed to the ammonite biozonation, the FO oi C. mexicana tion (H. becberi Zone) falls in the M23r Chron and the minor occurring in the Upper Kimmeridgian H. becberi upper part (5. darwini/V albertinum Zone) in theM22n Zone and the FO ol Parhabdolithus embergeri and P beck- Chron. The Kimmeridgian/Tithonian boundary identified mannìi occurrins in the Lower Tithonian S. darwini/V. as the boundary between the H. becberi andH. hybonotum albertinum Zone.The FO of C. mexicana minor (record- zones, accordingly falls in the M23n Chron. ed in Bed 108) and the FO of P beclemannii (recorded in Bed 1 1Z) are both correlative with a normal polarity interval, in asreenlent with the findings of Bralower et al. Proposal for the Tithonian basal boundary (1989) in the Atlantic Ocean and in the Subbetic Zone of the Betic Cordillera of southern Spain. The stratigraphic The present paper is a partial summary of the position of the FO of P embergeri is youneer than previ- work done on the whole section of ContradaFornazzo ously recorded (Bralower et al. 1989), since this species at Monte Inici by Bovero (2001). After his master thesis, usually appears before the FO o{ C. mexìcana minor.The a further large amount of ammonites v/as collected, and studied sanrples show,r high diagenetic overprint, domi- research on the calcareous nannofossils and the paleo- nated by dissolution andl or overgrowth; this could ac- magnetic record was completed. Nevertheless, field re- count for the obliteration of the main diagnostic features search is in progress both on the Fornazzo outcrops (e.g. of this species (blocky rim and spines) and suggests that for biostratigraphic allocation of Bed 109) and on other this datum should be regarded as a preservation one. In secrions around Monte Inici, like Balata di Baida (Christ Upper Jurassic successiott of Monte Inici, \X/. Sici\, 337

Geographical location: Europe, Southern ltaly, \X/estern Sicily, some 3 km south-u,est of Casrellamrnare del Golfo, Trapani Province. Topoeraphic nrap: Sheet 256, Alcamo (l:50.000), UTM coordinates uc l 0710955. Accessibility: The outcrop, at 700 m ;rltitude, on rhe north-u'estern slope of Monte Inici, is easily accessible by the service road lerdine to the old "marble" quarry of Contrada horna,zzo. Position of the boundary stratotype: Meter 30.5 from the base of the Rosso Ar.nmonitico Fm. nreasured in the succession of Contrada For- nazz-o. The boundarv is fixed at the base of Bed 1 10 (Fig. l0), some 5 meters abovc thc beginning of the upper R. A., in alternating calcareous and nr;rrlv nodular facies located at the bend correspondinu to the nrorphostructurtrl crest that goes dorvn Iront Piz,zo delle Niviere to Contr;rda Frauìnesi. Ammonite biostratigraphy: The boundary is defined by the first occurrence of specinr ens of Hybonoticeras gr. hybonotum, u.hich classically Fis. l0 - Nodular limestones of the b:rsal upper Rosso Anrmonitico marks the base of the'Tithonian; significant allied taxa ere Éll,bonoticeras Fm.; scction below the Fornazzo road. The Kinrme'ridgiln- robustunt tnd H aploceras stasz1tg11.

Tithoniln boundarv is located at the b;ìse of Bed I 1 0. Hrnr- Multidisciplinary correlation: The first occurrence of the assemblage mer for sc,rle to the right of l.rbel of Bcd 110. with Hl,bonoticeras gr. lrybonotum is ersill, correlatable through the Teth- van Realnr. Further correlation tools derìr'e from calc:rreous nannofossil biostratigraphy and magnetostratigrephy, according to which the proposed G.S.S.P lies respectively a little above the lower boundary of the Conusphaera mexicana Zone, and within the M23n Chron. 1960) so that the lower boundary of the Tithonian Stage Geoconservation: The outcrop FZ4 is locared in the Monte Inici pro- of Western Sicily could be described more accurately in tected arca, t,here no developnrent is allowed. The site is very lttractive the near future. for the spectacular vie*. on the bay of C;rstellammare del Golfo. However, the data obtained appear to be sufficient to justify proposing the Contrad^ Fornazzo section as the possible boundary stratotype (G.S.S.P) of the Titho- nian Stage (Fig. 9). It meets the requirements repeatedly en-rphasized by the International Subcommission on the Acbto,irledgnenrs. The author would like ro thank N. Morton, G. Stratieraphy according to the euidelines summa- Jurassic Schs,eigert and A. Zeiss for the critical revisions of the nranuscript. A. rized by Remane et al. (1996). Bovero and F. Cecc;r ere thanked for collaboration during field rvorks. The research hrs been co-funded by the Italian University Ministry and Summary of proposal for the Tithonian Stage G.S.S.P by the Torino Urriversity (grants to G. Pavia 1999 md 2001, nurnbers Name of the boundary: base of Tithonian. 99043 I 81 55-1 and 2001048153-1 respectively). Financial support also Rank of the boundary: (chronostratigraphv) Stage; (geochronol- from the Spanish BTE 2001-3029 McyT within the frame of the EMMI og1') Age. GROUP (RNM178Junta de Andalusìa).

REFERENCES

Allouc J. (1990) - Quaternary crusts of the Mediterr:rnean Sea: Caracuel J.E & Olóriz F. (1999) - Recent data on the Kirn- a tentxtive explanation for their gcnesis. Marine Geolog,, rneridgian-Tithonian boundary/ in the Sierra Norte of 9 4: 205 -238, Anrsterdam. Mallorca (Spain), with notes on the genus H),bonoticeras Bovero A. (2001) - Analisi paleontoloeica e stratisrafica del Breistroffer. Geobios, 32: 575-591, Lyon. Rosso Anrnronitico (Giurassico medio-superiore) nell;r Caracuel J. E., Olóriz F. & Sarti C. (1998) - Updated bios- sezione bornazzo di Monte Inici. Sicilia occidentrle. Mrs- tratigraphv of the Kimrneridgian and Lower Tithonian ter Thesis, Univ. Torino, unpublished, Torino. xt Lavxrone (Trento Plateau, Italy). Correl:rtion for epi- Bown PR. & Cooper M.K.E. (1998) - Jurassic. In Bown PR. oceanic western Tethys. Geologica et PaLaeontologica,32 : (ed.), Calcareous Nannofossil Biostratigraphl'. Chaprnan 235-25 |, Marburg. & Hall: 34-85, Carnbridge. Cariou E. & Hantzpergue P, eds. (1997) - Biostratigraphie du Bralon.er T.J., Monechi S. E: Thierstein H.R. (1989) - Calcar- Jurassique ouest-européen ct rnéditerranéen: zonations par- eous nannofossil zon:rtion of the Jurassic-Cretaceous allèles et distribution des invertébrés et microfossiles. Bzl/. boundarv interval and correlation with the geomagnetic Centre Recb. Elf Explor. Prod. Mém., 17: 440 pp., Pau. polarity tirne scale. l'larine Micropaleont., 14: 153-235, Catalano R., Lo Cicero G. tr Sulli A. (2002) - Geology of Sic- Amsterdan-r. ily: an introduction. In: Santantonio M. (ed.) - General 338 G. Patia, R. Ltutza, I:. Loz,tr, L. trlartira, F. Olóriz E:. E. Zartelld

Field Guide Book, 6,r Irrternation:rl Svnrp<-rsiunr on rhc Olóriz F. (1978) - Kirìrncridsicnsc-Tithonico inferior cn cl sec- Sysrcnr: 5-20, Jurassic Gcda, Torinc-r. tor cenrral clc ll Zon:r Subbéticr. palcorrtologí:r. Bioes- Ccccr F'., Sl'arv 8., B:rrtolini A., Rcuranc J. & Cordev lr. (2OO l) rrxrisrafía. PhD thesis, Urrir'. Gran:rda. lg4 (i926): Z5S - The Midcllc Jurrssic - Los'cr Cretaceous succcssion of pp., Gr;rnacll. Monte Inici (Trapanese donr;rin, Westcrn Sicih.): scdi- Olóriz F., Molina-Moralcs,J.M. & Serna-Barquero, A. (1999) - nrcnrolosv, biostr:rtier:rphv and isotopc strrrtiuraphr.. Bl//. Rcvisión esrr:rtiqrificî dcl inten,alo Kinrnreridsiense nrc- Soc. géol. Francc, 172: 617 -659, Ptris. clio - Tìthonico brsal cn el perfil G.del sector dc Vcnta Channe I Oldol'J.S., J.E.T., Crrrrl:rno R. & D'Arse nio B. ( I 990) (Sierrr Gor.dr, provincir Je Gr.rnad,r). palaconr:rgncticallv Qr.rcsad:r Geoga- - detcrnrined rot:rtions in the s.cst_ ceta, 26: 7l-74, Madrid. ern Sicilirn (r4 fold and thrtrsr belt. kctottics,9: l-660. Olóriz F'. & Schive iscrt G. (2OO l) - Tithonian \Washington. Working Group. In: Morton N. c\ Borvn P (cds.): Intent. Subcottttrt. Christ H.A. (1960) - Beitr;iec zur Stratirrrphic .rnd p:rliorrtol- -f urassic Strat., Neii:slutet,28: lO-ll. London. o{:ie des M:rlnr von Westsizilien. Schi;,ciz. pal,fuutt. AbL.. Olóriz F'. & Vilhscnor A.B. (1999) - Ne s, rricroconchirtc H1,- 77: l-ll pp.. B.rscl. bonoticcras fronr Mexico. Geobios, 32: 561-573, Lvon. Clrrri PA.,Mrrini P, Parstorini M. & Pavi:rG. (l9tì1) - Il Rosso Pavirr G. & Crestr S., coord. (2002) - Revision of Jurassic rnr- Anrnronitico Infcriore (Baiocilno-C;rllovi;rno) nci Mon_ nronircs of the Genrnrcllrro collcctions. euad. A4usco ti Lessini scttcntriorrali. palarntt. Rir;. Ital. Srrirr.,9O: l5_ G.G. Genntcllaro, 6: +Otì pp., Prlcrn.ro. 86. Mil:rno. Prrvi:r G. & M;rrtirc 1,. (1997) - Tl.rc inrport;rncc of trphononric Clari PA. & Martire L. (1g96) - Inte rplav of se dinrcntationi rìrr- str.rdics on biochronoloev: ex,ulplcs fronr the Europc;rn chlr-rical rncl chcnricrl conlp:ìction in notlr,rl;rr lir-ncstoncs of Middlc Jur:rssic. Cuad. Gaol. Iberica,23: 153-181, Ma- the Rosso Arlnronitico Vcronese (Middle-Upper Jur;rssic, drid. NE Irrlr')../ormt. Sed. patrol., 66:.{.tZ-.15g, Tulsa. Rcnr;rnc J., Brsset M.G., Cou'ie J.W, Gohrb.rndt K.H., L:rne Di Stc'fano P (2002) - An outlirre of theJur:rssic sîrxrierrphv rncl H.R., Michclsen O..t Nris'cn \( (1996) - Reviscd euide- p:rlcoecoer:rphv of \Westcrn Sicily In: S:rrrt;rntonio M. (cd.) lincs for cstrblishnrcrrt of globll chror-rostratisr:rphic - Gcncral Field Guidc. Book, (r'u Internltion:rl Svrrposiunr stlrrdards by the Interr-r:rtional Contntission on Str:rris- on theJurxssic Svsrcnr:2l-27. Geda, Torirro. raphv (ICS). Episodcs. t9,3:77-81, Bcijne. Fern:índez-Lópcz- S. (199 l) - Tlphonorric conccprs for ,t the_ S;rrti C. (1993) - Il Kinrnrcrideirno dellc prcalpi vcneto-tren- orerical biochronology. ILe.i:. Espan. krluntt., 6: 37_19, tine: faun,r c biostratierafitt. Museo Ciu. Sr. Natur., LIcn. Oviedo. 5: l5-l pp., Vcronrr. Floriclia G.B. ( 193 l) - Osse rvazioni seoloeichc sul Monte Inici. SchrvcirÌcrt G. (2000) - Nerv biostratigraphic drt,r from thc Boll. Soc. Ccol. Ital.,5O: 3Z-.19, Ronr:r. Kinrmcridsi:rn/Tithoni;rn boundary becls of SV Gcrnr:r- Genrrrrcllaro G.G. (1U78) - Sopra i ccfalopodi cle llir zon:r infcri- nr'. GeoRcsc:rrch Forunr, Trans. Tech. publ. Ss,itzcrland, orc dcgli srrilti con/ryirtocer,rs actnthicult c.li Sicili.r.,4ri 6: 195-202. Uetikon-Zurich. Accad. Giocttitr Sc. Natur., l2: 153-250, Crtini:ì. Sch*'eisert G., Krishnr J., P:rndcv B. & pathrk D.B. (1996) - Kaencl dc E., Berscn J.A. & r'on Salis K. (19g6) - Jurassic c:rl- A ncn. :rppro:rch to thc correlation of thc Upper Kinr- crreous n:rnnofossil biostrati gr:rphv of Wcstcrn L,uropc. mcridsirn llcckeri Zone rcross the Tcthvan Sea. N. /ó. Con-rpilation of rcccr.rt studics and c,rlibr,rtion of bio_ Gutl. Pal,iottt. Abb., 202: 3+5-373, Sruttr.r;rrt. cvcnts. Brrl/. Soc. géol. I paris. Fr,utce, 996: I 5-28, Tuckcr M.E. S{ Wrisht V.P (1990) - Carbonatc sedir.nentolosv. Los'ric \({ (1990) - Identification of fcrronr,.rgnetic nrincr,rls in Bhckwcll, 182 pp., Oxforcl. a rock br- cocrcivit.r' rnd r.rnblockinrÌ propcrries. Ccoph1,s. Villascior A.B., Olóriz- F. c\ Gonz:ílez-Arrcola C. I2OOO) - Ilcs. Lctt., l7: 159-162, Wirshinston. Rcccnt rdr,,rnces in Uppcr Jurrssic (Kinrnrcridgirn-Ti- Mrrtirc t-.8i Pavi:r G. (2OO:) - Post-Si.nrposiurrr lìicld Trip Ill: thonian) :Ìnlnronire biostr:rtieraphv fronr norrh-ccnrrrl the Trrìp:lnese Dont:rin. In: S:rnrlntonio N4. (ed.) - Gcn- Mexico based on nen' collcctcd ar-r.rrr.ronite ,lssenrblaqcs. crrl Iricld Guidc Book, 6, , lntern;rtionrl Svurposrunr on GeoResc:rrclr Forum, Trrns. Tcch. publ. Ss,itzcrl:rnd, 6: thc j- Julrrssic Svsre rn: Il 166. Ccd,r. T.rrinir. 219 -26 I, Uctikon-Ziirich. Mullins H.T., Ncunrrrrn A.C., Wilbcr R.J. c\ Bo:rrdrr:rn M.R. Villascnor A.B., Olóriz F-., L;rra. L, Gonzílcz-Arrcola C. Ec Dc (1980) Noclular - crrbonatc sedimcnt on B:rhanri:rn L:r Morrr A. (1994) - Honror:rxv and the KirrnrcridrÌirn/ slopes: possiblc precursors to nodul,rr linrestoncs. ,/. Tirhoniln boundarv in n.,rth-icntr.rl Mcxico. +', Intcr- Scd. Patr.,50: ll7-131, Tirls:r. nirrion;rl Congrcss on Jurassic Geologv and Stratigraphr,, OSS J.G., Stcincr M. B., Olóriz Ii. & TrvcrrJ. M. (1981) - Abstracts: 4(r, Mcndoz-a. rass ic nrirsncosrrxr;srrph\,, Ju l. Kimnrcriclsirn-Tithon i_ Wendt J. (1964) - Stratieraphisch-prlziontolouischc Untcrsuc- rn of Sie rrl Gord:r and C:rrcabuer', sourhe rn Spljn. Earth hunsen inr Dogge r\Wcstsiziliens. Boll. Soc. paleottt. Ital., Planet. Sci. Lett., 7 l; 147-162, Anrsrerclam. 2 (1963): 57-145, Nlodcn;r.