Correlating Marine Palynomorph Variations with Sequence Boundaries of Upper Jurassic Sediments in a Basin of Northern Switzerland

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1 Iraia It. J. Sci. 2(1) 2001 Crrlatig Mari Palymrph Variati with Squc Budari f Uppr Juraic Sdimt i a Bai f Nrthr Switzrlad Ebrahim Ghami-Njad Dpartmt f Glgy, Faculty f Scic, Uivrity f Thra, Thra - Ira. ghami@khayam.ut.ac.ir Abtract Variati i th umbr f diflagllat cyt pci rcvrd frm th Rhda-Swabia dimtary bai i rthr Switzrlad hav b crrlatd with quc ad dimtary cycl tablihd fr thi bai. Th variati i diflagllat cyt abudac crrbrat th quc budari rctd by Gygi t al. (1988) uig thr paramtr uch a lithlgy ad macrfil ctt f th dimt. Hightad f a lvl ar markd by a harp icra i pci divrity (mtim up t 50). I ctrat, lwtad ar idicatd by a harp dcli i th abudac f pci: i a ca ly 3 pci. Kywrd: Diflagllat, Uppr Juraic, Squc budari, Switzrlad. Itrducti I 1992 t diffrt lcaliti acr th Rhda-Swabia dimtary bai i rthr Switzrlad wr ampld (Fig. 1) ad vr 120 ampl frm Uppr Juraic dimt wr cllctd. A cmprhiv prjct wa udrtak t tudy th palymrph ctt ad th palvirmt f thi bai frm 1992 t Th rult wr publihd i a vlumiu mgraph by th authr ad hi cllagu i 1999 (Ghami Njad t. al. 1999). Wh thi mgraph wa i pr, quc tratigraphy f th am dimt wa publihd ad quc, cycl ad budari wr tablihd by Gygi ad hi cllagu (Gygi t al. 1998). Thi rct wrk f Gygi ad cllagu brught th quti t my mid "whthr r t mari palymrph ca cfirm th quc budari rctd fr th dimt". Thak t my cmputr wh had kpt all th data hady ad availabl. I wa i a piti t r-xami ad crrlat

2 ÒÓ E. Ghami-Njad IIJS, 2 (Gl.), 2001 th rult btaid frm th variati i th abudac f mari palymrph with th quc budari rctd by Gygi ad cllagu by uig thr charactr uch a lithlgy ad paltlgy. Thi papr i thrfr th rult f tatitical calculati diflagllat cyt abudac ad a cmpari with th rult publihd by Gygi t al. i N Grmay Schaffhau Frac Bal Rhi Mllik Prrtury Librg St-Ura Syhir Dlmt Lauf Olt Auti Aar Aarau Bad ampld it Tw/villag Balthal Srta Mutir 0 50 km Pry Figur 1 - Lcati map f th tudid ara ad th ampld it. Stratigraphy Sdimtati i rthr Switzrlad bga i a pictital a adjact t th Tthy. Th dpth f thi a wa lat i th rthwtr ad gratt i th uth-atr part (Gygi, 1990) Th rat f dimt upply ha b abut zr jut bfr th d f th Middl Juraic. Cqutly, thi a wa a tarvd bai frm mid Callvia t arlit Oxfrdia tim. Sdimtati rcmmcd lwly at th bgiig f th Oxfrdia ad prducd a thi, widprad markr bd f ir-litic marl f th upprrmt Hrzach Frmati (Gygi 2000). Gygi (1986) ccludd that, frm a paladpth f abut 80 mtr dwward, cphalpd cmprid mr tha 80% f th macrfaua. Th macrfaua f th ir-litic hriz at th ba f th Rggri Mmbr ar Péry i 84% cphalpd (Gygi & Prz, 1986). Th ir lit ad th cphalpd faua dmiatig thi layr thrfr

3 Crrlatig Mari Palymrph Variati ºººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººº ÒÔ idicat a watr dpth f l tha 100 mtr (Gygi 1981, Gygi & Prz 1986). Th abudac f ir id dcra tward th tp f th markr bd ad fad away cmpltly at th ba f th Rggri Mmbr a a rult f a icraig rat f dimtati whr th blu-gray marl-clay f th mmbr bgi. Th budary btw th Middl ad Uppr Juraic i rthr Switzrlad i thrfr placd withi th frrugiu marl-clay blw th Rggri Mmbr (Gygi t al. 1998, Ghami-Njad t al. 1999). Th thi frrugiu layr i vrlai by a ma f blu-gray marlclay f th Rggri Mmbr that i vral t f mtr thick i th Clay Pit at Ampthil ar Librg (Fig. 2). Th macrfaua f th lwr Rggri Mmbr cit mtly f cphalpd, althugh thr rgaim uch a bivalv, gatrpd, brachipd ad criid hav al b rprtd (Gygi 1986, Gygi & Prz 1986). I rthwtr Switzrlad, th Rggri Mmbr i vrlai by th Trrai à Chaill Mmbr, cmpd f 40 t 50 mtr f gray marl with bad f limt ccrti ad, i m ara, bad f marly limt (Gygi t al. 1998). Th gray marl, with bad f limt ccrti, f th Librg Mmbr vrli th Trrai à Chaill Mmbr. Th Librg Mmbr diffr frm th Trrai à Chaill i havig l itrpac btw th dul bad ad i th irrgular hap f th dul (Gygi & Prz 1986). Th carbat platfrm dpit f th St-Ura Frmati, wh thick vari btw 35 ad 95 mtr i diffrt ara, vrli th Librg Mmbr. At th dital margi, th frmati ctai cral bihrm that ar i tur rplacd furthr baiward (atward) by a ucci f wll-bddd limt ad lim mudt f th Pichux Limt. Th Pichux limt, a dimt f th platfrm lp, i traitial btw th platfrm dpit f th St- Ura Frmati with cral ad th baial Birmtrf Mmbr that blg t th ammit faci (Gygi 1986). Th Birmtrf Mmbr i th at i a bitrm f ilicu pg with abudat ammit ad ha a avrag thick f abut 5 mtr (Gygi 1992, Gygi & Prz, 1986).

4 E. Ghami-Njad IIJS, 2 (Gl.), 2001 ÒÕ F ig u r 2 - T im - tra tig ra p h ic p iti f C a l v ia -O x f rd ia lith tra tig ra p h ic u it f th rth r S w itz rla d d im ta ry b a i (fr m G y g i, w ith m c h a g )

5 Crrlatig Mari Palymrph Variati ºººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººº ÒÖ Squc budari vru variati i Palymrph abudac A carbat platfrm wa tablihd i th rthwtr Switzrlad dimtary bai by Middl Oxfrdia tim. Thi platfrm ctiud t xit thrughut th Lat Juraic. Rct tudi by Gygi ad cllagu (Gygi t. al. 1998) hav idicatd that th Oxfrdia dimt a a whl rprt a 2 d -rdr rgri- tragri cycl, puctuatd by ight 3 rd -rdr cycl. Th tart f tragri i markd by a dcra i th trrigu iflux ad rtrgradati f th carbat faci acr th carbat platfrm. Maximum fldig i charactrizd by a lwdw r v trmiati f th grwth f cral rf th platfrm, cdati f th bd ad m tim by th dpiti f a cdd filifru hriz i th bai (Gygi t al. 1998). Th tp f th Lambrti Bd i th uppr Hrzach Frmati (Callvia-Oxfrdia budary) i itrprtd a a maximum fldig urfac bcau f th rich macrfaua ad cdd atur f th bd (Gygi t al. 1998). Th vrlyig 20 cm calcaru, lightly ilty clayt with cattrd ir id f th upprmt Hrzach Frmati (Gygi, 2000) dirctly blw th Rggri Mmbr ad th lwr part f th vrlyig lightly ilty calcaru clayt f th Rggri Mmbr cmpri th hightad ytm tract (Gygi t al. 1998). Sampl #2 f Ghami Njad t al. (1999) wa tak frm th calcaru clayt with ir id dirctly blw th Rggri Mmbr ad ctai 58 pci f diflagllat cyt (Fig. 3). Th Rggri Mmbr cmpri abut 70 m f mtu prly bddd, ilty clayt with cattrd ammit, blmit, ad brachipd. Thr i a harp clr chag i th middl f th mmbr frm a light bluy-gray blw t a mr uifrm light gray abv, that i cicidt with a icra i ilt ctt ad i itrprtd a quc budary O1 (Gygi t al. 1998). Sampl #7 f Ghami Njad t al. (1999) wa tak frm th layr frmig th uppr budary f th firt cycl, O1. Oly 12 diflagllat cyt pci wr rcrdd frm ampl #7, whra 50 pci wr fud i th prcdig ampl #6. Thi cfirm th rult btaid frm lithlgical ad paltlgical tudi by Gygi t al. (1998).

6 ÓÍ E. Ghami-Njad IIJS, 2 (Gl.), i c p40 f r b30 m u O O O ampl umbr 8 7 O Figur 3 - Numbr f mari palymrph pci vru ampl umbr fr Uppr Juraic trata f th rthr Switzrlad dimtary bai. O1 - O4: Budary f cycl Sampl #1: Calcair Rux Sablux uit Sampl #2: Ir litic uit Sampl #3 - #11: Rggri Mmbr Sampl #12 - #19: Trrai à Chaill Mmbr Sampl #20 - #21: Librg Mmbr Sampl #22: St-Ura Frmati Th Rggri Mmbr i vrlai by th mr calcaru Trrai à Chaill Mmbr. Th harp chag t mr carbat-rich faci at th ba f th Trrai à Chaill Mmbr rprt a hallwig f th a watr ad i itrprtd a rprtig th uppr budary f th cd cycl, O2, at it crrlativ cfrmity (Gygi t. al. 1998). Ufrtuatly data ad palylgical lid frm th ba f th Trrai a Chaill Mmbr wr t availabl fr r-xamiati. Hwvr, ampl #13 f Ghami Njad t al. (1999) tak frm abut

7 Crrlatig Mari Palymrph Variati ºººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººº ÓÎ 13 mtr abv th brdr btw th Rggri ad Trrai à Chaill Mmbr idicat a harp dcli i umbr f pci with ly 3 rcrdd pci. Th umbr f pci i pcially imprtat wh cmpard with that f th prcdig ampl (#12) tak frm fur mt blw i which 35 pci hav b rcrdd. Thi thrfr may idicat xitc f a budary that ha t b dtctd by Gygi ad hi cllagu (1998). I th prt papr thi budary ha b markd a O2 (Fig. 3). Hwvr, if futur tudi cfirm xitc f thi budary th th frmrly dtrmid cycl budari hav t b chagd accrdigly. Th uppr part f th carbat-rich Trrai à Chaill Mmbr ctai vral thick, wll-dfid limt bd itrbddd with marl-clay. Th firt thick tabular limt i itrprtd a th uppr budary f th third cycl, O3. Thi budary crrpd with th layr frm which ampl #19 wa tak. Oly i pci f diflagllat cyt ar rcrdd frm thi ampl ad cmpard with th prcdig ampl (#18) with 53 pci, cfirm th layr a f big th budary. Sampl #20 ad #21 wr tak frm th Librg Mmbr vrlyig th Trrai à Chail Mmbr. Oly a mth icra i umbr f diflagllat cyt rcrdd frm th ampl i viibl Fig. 3. Th Librg Mmbr i vrlai by th St-Ura Frmati with a baal clitic ad litic grait. Th ba f th St-Ura Frmati i itrprtd a th quc budary O4 (Gygi t al. 1998). Th lwr part f thi frmati i itrprtd a hlf-margi ytm tract. Sampl #22 wa tak frm th ba f th St-Ura Frmati. Oly v pci hav b rcrdd frm thi ampl whil, ampl #21 iclud 17 pci. Thi al cfirm th ba f th St-Ura Frmati a big th quc budary O4. Cclui Icra ad dcra i th umbr f diflagllat cyt pci rcrdd frm th Uppr Juraic dimt f th Rhda-Swabia bai i rthr Switzrlad ca b crrlatd with quc budari tablihd fr th dimt. Variati i th umbr

8 ÓÏ E. Ghami-Njad IIJS, 2 (Gl.), 2001 f pci cfirm th rctd budari by uig thr charactr uch a lithlgy ad paltlgy. Th uppr budary f th cd cycl f Gygi ad hi cllagu culd t b cfirmd bcau data ad palylgical lid f th ampl frm th layr frmig thi brdr wr t availabl fr r-xamiati. Hwvr, a harp dcra i umbr f diflagllat cyt pci wa rcrdd withi 13 mtr frm th ba f th Rggri Mmbr ad thi may al b markd a a budary that wa t dtctd by Gygi ad hi cllagu (1998). ACKNOWLEDGMENTS Th authr ackwldg ctructiv uggti giv by th Iraia Itratial Jural f Scic rviwr. A arly draft f th maucript wa al rad by Dr. R. Gygi f th atural hitry muum f Bal, Switzrlad wh criticim ad cmmt highly imprvd it ctt. REFERENCES Ghami Njad, E., Sarjat, W.A.S., ad Gygi, R., (1999) Palylgy ad palvirmt f th Upprmt Bathia ad Oxfrdia (Juraic) f th rthr Switzrlad dimtary bai. Schwizrich Palätlgich Abhadlug, 119, 130p. Gygi, R.A., (1981) Olitic ir frmati: mari r mari? Eclga glgica Hlvtia, 74(1), Gygi, R.A., (1986) Eutatic a-lvl chag f th Oxfrdia ad thir ffct dcumtd i dimt ad fil amblag f a pictital a. Eclga Glgica Hlvtia, 79(2), Gygi, R.A., (1990) Th Oxfrdia ammit ucci ar Librg BE ad Pry BE, rthr Switzrlad. Eclga glgica Hlvtia, 83(1), Gygi, R.A., (1992) Structur, pattr f ditributi ad palbathymtry f Lat Juraic micrbialit (trmatlit ad cid) i rthr Switzrlad. Eclga glgica Hlvtia, 85(3), Gygi, R.A., (2000) Itgratd tratigraphy f th Oxfrdia ad Kimmridgia (Lat Juraic) i rthr Switzrlad ad adjact

9 Crrlatig Mari Palymrph Variati ºººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººººº ÓÐ uthr Grmay. Mmir f th Swi Acadmy f Scic, 104, 152 p. Gygi, R.A., & Marchad, D. (1993) A Early Oxfrdia ammit bd i th Trrai à Chaill Mmbr f rthr Switzrlad ad it quc tratigraphical itrprtati. Eclga glgica Hlvtia, 86(3), Gygi, R.A., & Prz, F. (1986) Miraltratigraphy, lith - ad bitratigraphy cmbid i crrlati f th Oxfrdia frmati f Swi Jura rag. Eclga glgica Hlvtia, 79(2), Gygi, R.A., C, A.L. & Vail, P.R. (1998) Squc tratigraphy f th Oxfrdia ad Kimmridgia tag (Lat Juraic) i rthr Switzrlad. Mzic ad Czic Squc Stratigraphy f Eurpa Bai, SEPM Spcial Publicati 60,