4 了了

勿 G M apper, R Feist, R T Becker and M R H ouse 'vW'%efinition of the Frasnian/Fam ennian Stage b oun d ary

盆 The boundaryfor the F rasnianlF am ennian Stage G lobal low er thanform erly used boundary levelsfor the base of Stratotype Section and P oint (G SSP) has been ratif ed 勿 the F a m en n ian . IC S and IU G S and is draw n in a section exp osed near the Upp er C oum iac Q uarry in the southeastern M on- tagne N oire, F rance. The p osition of the boundary w as In tro d u ctio n selected 勿 the Subcom m ission on D evonian Stratigra- phy in 1991 to coincide w ith the low er boundary of the H istorically, several different levels have been used to define the Low er Palm atolepis triangularis Zone in the conodont base of the Fam ennian. In the type area for the nam ing of the stages biostratigraphy. The revised defi nition of the low er in southern B elgium , precise docum entation in recent years has been boundary of the zone, p rop osed herein, excludes the given to a new reference section replacing the now -infilled classic section in the Senzeilles railw ay cutting (B ultynck and others, 1988). extrem ely rare occurrences of Palm atolepis triangularis L argely resulting from w ork in the first quarter of this century in G er- a few centim etres low er, w ithin the upperm ost conodont m any, another boundary w as used that w as based on the entry of the zone. The G SSP also coincides w ith the boundary goniatite C heiloceras in the pelagic realm . In the latter half of this betw een the C rickites holzapfeli Zone and the Phoenix- century the considerable grow th of conodont studies has led to m uch refinem ent of the biostratigraphy. H ow ever, the level taken as the ites frechi Z one in the goniatite scale. The p osition of t he b ase o f th e F am en nian h as varied b etw een a le vel at the b ase o f the G SSP is im m ediately above a m ajor horizon of extinction crep ida Zone dow n to the base of the L ow er triangularis Z one. The w ithin the D evonian and is stratigraphically som ew hat need for an international definition has becom e urgent. The Subcom -

0 1 0 K M ，B e d a r ie u x A -?00/ 因 ．．二，二， ，气 Les D E V O N ！A N ／了 阅 花 二 ／ 夕与'0OUUAI RIRI:Ym ．沙uranqe5 区鼓习 尹 洲 }"Q飞，’ 一／’“’7 妙 牙'to cessenon 。Q户 w l}- 二又弓一扮代v

O C o u m ia c 0 10 0 m L一一 」

N a za ir e d e La d a re z

P R O V ／刀 C E 六 B e d a rieu x A u rig n a c 子 +叼o n tp e llie r To u lo u s e N ，亡a u sse s e t 。。瞿 Vey ra n M ag a la s L卜14 阿 E D I T E R R A N E A N A 卜 、＿， ．、 0 一 10 0 K M ＋C e s s e n o n s 尸 A I N ． 一」 －

Figure] M aps showing theposition oft he M ontague Noire in southeastern Francea nd oft he Upper户umiac ＿ Quar7y near Cessenon, the site oft he GlobalS tratotype Section and Point (GSSP)fort he definition oft he base oft he F am ennian Stage (insetm ap A ). M odifi edfrom B eckera nd oth ers (1989).

E pisodes, Vol. 16, no. 4 4 3 4

m ission on D evonian Stratigraphy (SD S) has given careful consider- adjacent to the southeastern border oft he disused upper m arble quarry ation to w hich level is m ost appropriate for international correlation (U Q ) of Courniac, 175 in W SW of the Les G ranges farm house, about and it decided, at a m eeting in W ashington in 1989, that a GSSP 1.5 km N IE of C essenon village and 2 100 m SW of C ausses et V eyran. should be sought in relation to the base of the L ow er triangularis It can be reached easily by a path up the hill from near the track to L es conodont Zone. Final ballots and ratification by ICS and IU GS (in G ranges farm house from the road D 136 betw een C essenon and St January 1993) led to a level in a section at C ourniac, southern France N azaire-de-L adarez. T he ground is ow ned by the com m une of being designated as the G lobal Stratotype Section and Point (G SSP). Cessenon and is already protected as part of a w ater supply area. C on- A briefr eview of the docum entation leading to this decision is given servation and protection oft he section has been assured by com m unal here. The conodont and goniatite biostratigraphic divisions are and departm ent ofi cials. Free access for scientists is confirm ed. show n in figures 5 and 6. The sequence is one of pelagic calcilutites, m ostly red t in t e d It has been recognise d b y the Subcom m ission that, in general, and w ell bedded, w ith bedding probably controlled by M ilan- D evonian sections in pelagic realm facies are m ore likely to be com - kovitch-B and clim atic oscillations during sedim entation. T he plete than those in the neritic fa,cies. T he pelagic facies form s a better sequence has been described in published accounts (H ouse and oth- basis for the biostratigraphical precision needed for international cor- ers, 1985; M apper, 1989; B ecker and others, 1989 ; Schindler 1990; relation. In particular the conodont and goniatite records are better in B ecker 1993a) and is depicted in figure 2. T he boundary is draw n those facies. That is not to im ply that there are not facies rich in other betw een B eds 31g and 32a as show n in figures 2 and 3. D istinctive is groups, for exam ple spores and brachiopods, w hich are very im por- B ed 3 1 g w hich is correlated w ith the U pper K ellw asser L im estone ot tant for correlation, but it is norm ally easier to correlate into such sec- G erm any and w hich is a hypoxic dark grey calcilutite to calcarenite tions secondarily from prim ary sections in the pelagic facies. In the above w hich is the m ost m arked faunal boundary. B oth B eds 31g last resort the Subcom m ission concentrated on tw o such sections, one and 32a are characterized by pelagic faunas. at Steinbruch Schm idt in the R henish Slate M ountains, G erm any 0 ？ a l︵ e The sequence chosen show s a com plete s u c cession through the (Sandberg and others, 1990 ; Schindler, I 了 ‘ o th e r a t 价 early Frasnian to late Fam ennian. It is unfaulted and has no tectonic 以 e － a V C ourniac in the M ontague N oire (Feist, 1990 汀The latter w。 as finally 仁 a C t 理 problem s. T he beds are approxim ately vertical. Equivalent sections se le c te d b e c a u se o f th e b e tte r d o c u m e n ta tio n s sil g rou ps. can be found elsew here in the area. T he rocks are of low -grade m eta- m orphism and therm al m aturity (C A I 2-3) and com prise an hom oge- neous pelagic calcilutite sequence w ithout m arly or shaly interbeds. R ecom m ended stratotype T here is a com plete zonal succession w ith a rich fossil content, espe- cially of the biostratigraphically significant groups of conodonts, T he recommended boundary GSSP between the Frasnian and am m onoids, trilobites, tentaculites and ostracods. D etailed docu- Fam ennian Stages (D evonian) is above the U pper C ourniac Q uarry, m entation has been provided of this (Feist, 1990). G eochem ical near Cessenon, M ontague N oire, France (figure 1). T he section is sit- w ork across the boundary at C ourniac has also been published uated in the southeastern M ontagne N oire, D 6partm ent 1-16rault, D is- (G oodfellow and others, 1989; G randjean and others, 1989; G rand- trict of Cessenon (topographic sheet 1:25 000, N o. 2544 E , M urviel- jean-L6cuyer and others, 1993; Joachim ski and B uggisch, 1993; 1} s -13 6 zier s；L am bert's coordinates: x ＝130 375, y ＝658 55). It is G irard and others, 1993) and currently other investigations are being

N D eta iled Z V F igure 2 V m ap of t he 之加per － N一 N Q uarry at C ourniac, S N near C essenon, 喊 山 showing th e bed 比 乏 匡 哎 num bering and the 比 I I I4-r position of t he G SSP ！1 -1 }邢1 40 defi ning the base of th e F a m en nia n 1341二 口 州 日 ！ b etw een B eds 3 1 313 ． 3.6 , J7 ： and 32. M odifi ed P la n

户om H ouse and oth ers (1985). 12

S C A L E O F M E T R E S

(16)

F 仓ure 3 The d eta iled s u ccession FRASNIAN｝FAMENNIAN 0 .5 1.0 M E T R E of b eds around the G SSP level betw een beds M g and 32a 臼习 above the Upp er C oum iac Q uan y 泞 ‘ 、 酬川 队｛ 卿 ｛ 护 n ea r C essen on . ‘

尹 、 了 期 g o 21 12 － 9 16 15 19 15 16 +6 1'6 C M ． 9－ 6 16 1W7刊? e l e 护 i7e 9,18 33d 14- 14 r1 -3 5f 79-. C t d 1 二 f 30 3d，1e 3 2 3 3 B E D

D ecem b er 19 93 4 3 5

undertaken. M agnetostratigraphic w ork indicates that the area w as is a key sequence for the thirteen-fold M ontagne N oire Frasm an rem agnetized during the Perm ian. zcoatneadti oatn v (aMriaopupse sre c19ti8o9n)s, isnub Nsotarnthtia Alm paertisc ao,f Ww heiscther hna Aveus bteraelnia r,e panlid- Eatu Uropppeearn C Rousrsniiac (M exatpepnedrs afnrodm Fo Fsrtaesrm 1a9n93 Z,o fingeu 5re to 2) t.h Teh toep se oqfu Zenonce C orrelation of the p roposed boundary 13 （＝top of the Frasnian), but only the higher part of the Frasm an sea uen ce is o f co n cern h ere. lev el B ed 24a, the Low er K e ll w asser Lim estone, nas m e iow est occurrence of A ncyrognathus asym m etricus, w hich is the defining T he boundary level proposed represents perhaps the best correlated species for the low er boundary of the U pper gigas Z one in the zona- h orizo n in th e D evo nian . A rev iew of m o re th an 30 intern ation al see- tion of Ziegler (1962, p.23; 197 1). The conodont fauna of B ed 24a is tions has been presented by Sandberg and others (1988) including interpreted as the highest sam pled level of M ontague N oire Z one 12 localities in N orth A m erica and E urope. Further correlation is estab- (M apper, 1989, p. 456, figure 4). H ow ever, due to the facies of the lished in N orth A frica (B ecker and others 1988), C hina (Ji, 1989) L ow er K ellw asser at C ourniac, w hich apparently resulted in the and A ustralia (B ecker and others, 1991). T he boundary corresponds extrem e rarity of P alm atolep is in B ed 24a, a higher zonal identifica- to the extinction of all species of the conodonts A ncyrodella and tion cannot be excluded. N onetheless, the low er boundary of Zone O zarkodina and the loss of all but a few species of P alm atolepis, 13 is necessarily taken at the low est occurrence ofP aIniatolepis bog- P olygnathus, and A ncyrognathus, according to Sandberg and others artensis in B ed 24e (figure 5), as w ell as at the coincident low est (1988, pp. 293-294). There is a w ell-know n extinction am ong gom - o ccu rren ce of P a. h a ssi s.s. T h e lo w est o ccurren ce of P a . rhen an a atites of the G ephuroceratidae and B eloceratidae and the record for sensu M apper and Foster (1993, p. 24, figure 2) is high w ithin Zone both conodonts and goniatites at C ourniac dem onstrates this w ell. 13 in B ed 30b, coincident w ith the low est P a. boogaardi (figure 5). T he last of the brachiopod A tryp idae occurs just below the boundary It is notew orthy that species characteristic of the higher part of level (B ecker and others, 1991). A m ong trilobites the D alm anitidae, the Frasnian at U pper C oum iac, P alm atolepis bogartensis, Pa. w inchelli, Pa. rhenana, P a. boogaardi, A ncyrognathus asym m etri- Othdeo bnatosepl oefur tihdeae ,n Hd-aFrrpaestnidiane Uanpdpe Aru Klaecllowplaesusreirn Laeim aellst doinseap lpeevaerl oaft cus, and A ncyrodella curvata all term inate in either B eds 31f or 31g. B ed 31g. O thers have docum ented the global extinction of coral T he conodont fauna of B ed 31g, the U pper K ellw asser Lim estone, (Sorauf and P edder, 1986; Scrutton, 1988), strom atoporoid (Stearn, a nd has all but tw o of the foregoing species (figure 5) and is dom inated 1987) and acritarch (V anguestaine and others, 1983) groups A in term s of its Palm atolep is com ponent, by P a. bogartensis and Pa. there has been m uch recent local docum entation in m any areas.卜 w inchelli. O n evidence of the low est (and only) occurrence of A ncy- 1 at changeover of benthonic ostracod faunas across the boundary rognathus ubiquitus in B ed 31g, the fauna is apparently correlative C oum iac has been published (Lethiers and F eist, 1991). w ith the upper part of the lingu扣rm is Z one (Z iegler and Sandberg, 1990, p. 21), despite the absence of Pa. lingu扣rm is. In the M on- tagne N oire Frasnian zonation, B ed 3 1g represents the highest part C o n o d o n t rec o rd of Z one 13. A ncyrognathus uInquitus also occurs in faunas of the U pper K ellw asser L im estone at three other nearby M ontagne N oire T he conodont sequence at the Upper Coumiac Quarry extends from localities: C ausses et V eyran N orth and South, and L ow er C oum iac within the m iddle part of the Frasnian across the Frasnian/Fam enn- (Feist, 1990, pp. 19, 24, 30). A ll these faunas are correlative w ith the linguiform is Z one, but lack the nom inal species (B ecker and others, ian boundary and into the low er Fam ennian (as high as the U pper crepida Z one in the current sam pling up to B ed 44). U pper C ounuac 1989,pp.262,265).

F igure 4 黔 - - P hotograp h of th e su ccessio n a b ove 煞 the Upp er C oum iac 71,翼 Q uarry. The G SSP 盗 lies b etw een B ed 噢 3 1g and 32a. F or scale com p are w ith 纂墓 the profi le of t he beds given in fi gure 3. 雌夔瓣毅井 价鬓粱省岁彩孚擎七万黔 像一巍砂色＿坛 3 2 a 瓣嚎脚 了I‘ 了峪 了 I C

了 弃a

Episodes, Vol. I反no. 4 尸．．． ．月，，．网 ．．尸一～一 一一一～－， 一． — — — 不 花 一

4 了6

L ID W G R IO T T E F M F igure 5 R ange M ID D LE C O U M IA C FO R M A T IO N chart of c onodont F R A S N 认 N 2 日 12 7 1 2习 R31 sp ecies across the c l d l e 361.3l7b 138 1 . 3 I9b F rasnianlFam ennin , lb 1, Id le 1, lb Ic Id le la Jb Ic ja Jb ic id ．lb Ic Id le I& lb Ic ld la 11, a lb Ic Id le If 19

boundary at Upper Z O N E 12 Z O N E 13 ID 八 C oum iac Q uarry. L ． M ． The G SSP for the base of t he F am en n ia n is a t th e 瓶 ﹄S P in d e t base of B ed 3 2a. 傀 1 如月二e UQ 己 P osition of t h e p 0 u 吧b 七谈 upp erp art of 尘 F rasnian Z on e 12, 犯 比d U 二d 妞ern 口健口舀

F ra sn ian Z o n e 13 I. sy} b它1巧 ． ． ． ． (M apper, 1989), the L ow er, M iddle and R l h Q S 舀t 」七. d 酬刀m s创曰 皿」丁

Upp er triangularis A n ．几笼白S Q ．． 口 Z ones, and the I七． ef. 尸匕．b re u Ls ．．． L ow er and M iddle P a . LV W 沦 迸 f 二P a .. 曲 注匕位 crepida Zones is in dicated. R L c E P . r h - R ecognition of the ．．． Low er, M iddle and M e h l臼U P a rh 己n 口尸习1 功少er crepida 召lm} } Z o n es is cited in th e p 匕 text, but species 气 夕 ra n g es a re n ot I 勺 。 sh ow n a b ove B ed J 6 . 篡B,mrneph,k sp. Pa. 护' delicatuta & katuta ' 盆几飞 Id ehwtlad etfc at la

于 二一 一一 一 贡 m inufa rrdm ta 目日口 二二孟二．．． Ia. ten uipund a ta P. a叫 } a 份 ．Ag sinelarnm}

．．． - - d Pa. = I勺如 ate,娜 t} 是P, ap气, . ef. Pa.。＊ Pb．二内 山ana度h“污 A O. = A ncy- gnaU - P a.c rep 曰a ? (m e } 〔二J inferred rang e A n - =

R A N G E S O F C O N O D O N T T A X A A T T H E U P PE R C O U M IA C Q U A R R Y

Upper Coutruac Bed 3 Ig is also noteworthy．i n haying叩e confi- view perhaps could be supported in w hic h the latter is treated as an dently identified ＿s pecimen ot alniato‘ep‘s trangut仔ns 冬and o些 intraspecific m orphotype, w hich is apparently a com m on form of questionable specim en of the sam e species,呼 Igrm er usteu in月臀L, P a. triangularis in the L ow er triangularis Z one. Form s like the 1990, p. 36) am ong the m any examp es ot Pa. ogarrens‘s．a Da ra. holotype of Sannem ann seem to be relatively rare in this zone at winchelli. Although one cannot com plete坚exc，uge tn e possi甲liy 。‘ least in the M ontagne N oire. C learly the p raetriangularis m orpho- stratigraphical leak from the overlying 坤甲弓nn‘an, extre吧iy rare type crosses the Frasnian/Fam ennian boundary at Schm idt Q uarry, occurrences of Palmatolepis triangularts in tne upperm ost rrasm 哩 as w as w ell docum ented by Sandberg and others (1988, Table 1). are probably not unique to the UpperFourmac吻恻 ·’毛tie report ot [The 27 specim ens listed as Pa. p raetriangulan s in B ed 16 at 27 unfigured specimens i呼ent壑ed as塑. praetnangutans from thr Schm idt Q uarry occur w ith 3380 listed as P a. subrecta (a junior samples within Bed 功 ot te＿Upper Ke wasser Limes‘one a Se‘n- synonym of Pa. w inchelli, see M apper and Foster, 1993, but speci- bruch Schmidt (Sandberg and oters,‘丫匕匕,乡ab‘e止！may repre m ens of P a. bogartensis m ay have been included in this count)]. another Frasm an occurrence o1 尸a. tr angulars. inis interence is T hus, extrem ely rare Pa. triangularis as this species is delim ited based on M apper's study in 1990 oft he holotype and two paratypes of here m ay occur slightly below the level of the low er boundary of the P a. praetriangularis Ziegler and Sandberg (in Sandberg and others, L ow er triangularis Z one at both C oum iac and Schm idt quarries (up 1988, p. 304, pl. 1, figures 1, 3, 4), all from the highest bed of the lin- to 12 and 10 cm below the boundary, respectively). In both gu扣rinis Zone at H am ar Laghdad, southern M orocco. These three instances, this is w ithin the context of the dom inant upper Frasnian types (P a elem ents) have an arched outer-posten or platform , w hich fauna of the U pper Kellwasser Lim estone. Palm atolepts tnangu- gently rises from the lobe to j ust before the tip, then arches dow nw ard. laris does not occur in the beds equivalent to B ed 3 1g at the other This is exactly the sam e as in m any specim ens of Pa. triangularis in M ontague N oire localities cited previously. the Low er and M iddle triangularis Z ones; how ever, in the holotype It follow s, from the foregoing discussi o n , that there should be (Sannem ann, 1955, pl. 24, figure 3) the outer posterior platform rises m odifi cation of the definition of the low er boundary of the L ow er m ore steeply from the lobe to just before the tip, tnen＿a rcnes uown- triangularis Z one (Z iegler, 1962, P. 25; Z iegler and Sandberg, w ard. Consequently, the view is favoured here that Falmato吧 S tr- 1990, p. 22) for which the sole criterion is the first occurrence oft he angularis and Pa. praettiangulails are synonym s. A slightly different nom inal taxon. Instead it is proposed here to use for definition the

D e c e m b e r 1 9 9 3 4 3 7

abundant or flood occurrence of P alm atolep is triangularts, to the R ecognition of the U pper triangularis Zone (B eds 34a, 35a, virtual exclusion of other species of the genus, stratigraphically 36), the L ow er crepida Zone (B ed 37, on the unquestioned occur- above the fauna dom inated by the characteristic upper Frasnian rence of the nom inal species), and M iddle crepida Z one (B eds species. These include P alm atolep is w inchelli, Pa. bogartensis, Pa. 41-44) is straightforw ard, but not especially pertinent to the descrip- rhenana, P a. boogaardi, A ncyrognathus asym nietricus, A ncy- tion o f th e G S S P . rodella curvata (late form ), and in som e areas, P a. linguifon nis and P a. i.u n t ianensis. T hus, in the three sam pling intervals w ithin B ed 32a at U pper C oum iac (F eist, 1990, p. 36) and B ed 32b, Pa. trian- G o n ia tite rec o rd gularis is the only Palm atolepis species w ith the exception of tran- sitional specim ens here term ed P a. af . 'delicatula delicalula'. C ourniac is one of the few known places with。continuous goniatite N one of the species in Beds 31 and low er at Upper Counijac (figure successio n from the M id d le F rasnian to th e M id dle F am enn ian . 5) ranges above the G SSP positioned at the low er boundary of B ed A m m onoids occurb oth in the latest Frasnian (B ed 3 Ig) and b asalm ost 32a, except Icriodus altem atus, w hich is w ell know n to cross the Fam ennian (B ed 32a). Preservation, how ever, is in m any cases rela- Frasnian/Fam ennian boundary elsew here [the designation M ehlina tively poor, extraction tedious, and species-level determ ination is spp. represents several species w hose dem arcation is unclear]. The often difi cult. T he faunal record (fi gure 6) has gradually been built up new species of A ncyrognathus in B ed 32b is part of the Fam ennian over the past several years and certainly can be further extended. B ed- lineage including A g. sinelam inus and A g. cryptus and is m orpho- by-bed investigations w ere firstc onducted b y H ouse and others (1985) logically distinct from the m ain Frasnian A ncyrognathu s lineages and updates of faunal lists w ere supplied in consecutive years to SIDS that include A g. asym m etricus and A g. ubiquitus. C haracteristic and later sum m arised (in Feist, 1990). A detailed description of the upper Frasm an species of Polygnathus, such as P o. w ebbi and P o. Fam ennian part is provided in B ecker (1993a). decorosus, do not range above the G S SP and are replaced by P o. The boundary itself is clearly m arked by th e disappearance of brevilam inus and P o. n. sp. above the boundary at C oum iac. the gephuroceratids and beloceratids w ith the im m ediate subsequent T he low erb oundary oft he M iddle triangularis Z one, defi n e d by bloom of the tornoceratid P hoenixites frechi in the haem atite- the low est occurrence of Palm atolepis clarki and Pa. delicatula deli- enriched base of B ed 32a, but the species is know n to occur in late catula (Ziegler, 1962, p. 26; 1971, chart 5), is at the base of U pper Frasnian beds elsew here (B ecker, 1993a). Thefrechi (partial range) C oum iac B ed 32c. T he form er species is perfectly useable for defin- Zone or P hoenixites G enozone (do H -A ) is follow ed in B ed 35c by ing the base of the zone and that part of the original definition is fol- the entry of first Falcitornoceras and questionable cross-sections of low ed here. B ut use of the latter taxon is clouded by a taxonom ic C heiloceras. B oth genera are defining form s of the do 11-B . problem . That is, Pa. delicatula delicatula in the sense of m ost U ndoubted C heiloceras specim ens have not been collected below authors since 1962, and P a. delicatula platys ofZ iegler and Sandberg B ed 39 and earliest falcitornoceratids (especially those found in B ed (1990), are characterized by platform outlines of the Pa elem ent dis- 36) are still som ew hat interm ediate to Phoenixites. tinctly different from that of the lectotype o f│ P a . de lica tu la M IDD LE C O LIM IA C F O R M A T IO N LP P E R C O L IM I A C F O R M A T I O N L O W . G R│ I O T T E F M . │ │ B ra nso n a nd M e hl F R A S N I A N F A M E N N I A N │ │ │ (1934, pl. 18, figure 4; 。｝，｝：｝'l｝。│. lb I小 . 。│2lb5 1} a│｝。｝：Id 2│7│。｝。｝：k I-│。卜I小 ..3│ 0It,│。!b !} ld 1. !1！，│. lb I} Id卜｝，19│a｝。！：1, 1- 1, 。│13b4 1} 。│｝。！：！d｝． 3│6│..3 7lb 3│8│ 3} │ a new photograph in a . lb││ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ non-oblique view is av ailab le from G K o n 巴详嘿 } 一一一一一一一一 R AN G E S O F G ON I AT I 花 TA X A 囚 刀 f │ │ │ 解e n t. C f. 自U c 附 │ L P P E R O U A R R Y A T C O L IM IA C │ │ request). A s the solu- tion of this problem A u la t. c f. a u r ts L o │b o b a c tr lte s 甲 · │ │ c ann o t b e tre ate d 已王lo c e r as te rx iis tr fa tu 们 P h │o e n fxfte s f r e c h l│ │ fully in this paper, the Archoceras ．． 一 T or n o c- s ct t yp u m │ │ │ nam e of specim ens Tornoceras vel L}} u ofnoceras sp. W .－一 ．— 一一 一一 M ac tr it es a n el lu s │ │ │ corresponding to Pa. Aulatornoceras sp. — 一一 一一 一 一 二 盟 一o ce r as │ T . │ │ d elica tu la d elica tula C尝竿 }.2.. 一 一一 一一 一 P ho e nf xl te s cf . su lc a│t uS │ │ (sensu auct.) in U pper M a n t. c o rd a tu m │ W a l c 1to r n o ce r a s f a lc lC u │lu m │

C ourniac B eds 32c, M 朋 t. a d C 飞们5 心 │ L o b o b a c . te r m le ro │r u s │ 33c, and 34a is w rit- 尝550 之OI’me era “争 一 L o bo ba c . g u er ic h l │ │ │ ten in quotation m a rk s . 竺 t1coceras lam d9 p. │ │ │ C e│r a t a b e l o c e r a s s c h u lz i │ │ Lfrquat竺)oceras clausu│m │ │ Archoceras罗ulatum │ │ │ F igure ‘ R ange CrIckites halzapfelf│ │ │ chart of s uccession A r c h . c f. v a rlc o } m │ │ │ ofg oniatites sof ar

recordedfrom B ed － 一一一 一 ├───────────────────────────────────────────────────────────┤一 － ．．．．．．．‘二二二二名二口二二二二二．．－ │ 23 to B ed 3 9 in th e section arou n d th e G S S P a bo ve th e 邃 ，二。rd │ │ │ Upper Coum iac 巨亚理 taxonom│ic imprecission │ │ Q uarty, with the 【二］ infw ed range │ │ │ assignm ent of am m ono记 zones. F or correlation w ith

th e co no do n t 0 一i 】 │I一K │ │ │ I一L 1 1 一 A │ “ - B │ │ zonation, seefi gure (NEOM） A R C H O C │ER人3 ？ │ │ C RIC VJTE S P H O E N I Y J TE S │ F A L C IT O R ./ C │ K ( R A Y M O N D 】 │ │ 反

E n isod es. V oL 16 n o. 4 4 3 8

T h e C ourniac goniatite sequence generally m atches faunal suc- assem blages alternate w ith each other. T he first is characterized by cessio n s d escrib ed from classical sectio ns o f th e R hen ish S late great abundance of B eloceras tenuistriatum (e.g. in B eds 26d and M ountains and Thuringia. C orrelation w ith the new international 31a) and rarity of gephuroceratids and tornoceratids. O ther beds zonation based on the appearance and spread of genera (H ouse and have rich M anticoceras or C rickites faunas accom panied by m ore K irchgasser, 1993; B ecker and others, 1993; B ecker, 1993b) is abundant tornoceratids, and Buchiola. D ue to the lack of lithologi- straightforw ard, although there are regional features m irroring cal differences betw een beds containing the tw o faunal types it is local facies developm ents. For exam ple, international m arker gen- inferred that changing assem blages m irror fluctuations in the era such as Th m anticoceras, C arinoceras, N eonianticoceras and trophic structure. E specially the U pper K ellw asser L im estone Playfordites are still lacking in the M ontagne N oire area. L ate equivalents w ith their rich C rickites and pelecypod faunas associ- M iddle Frasnian beds at C oum iac, below the equivalent of the ated w ith unusually large ostracods but w ithout B eloceras m ay Low er K ellw asser Lim estone (B ed 24a), contain B eloceras, vari- have been deposited under eutrophic ecological conditions. T his ous m anticoceratids and som ew hat am biguous C ostam anticoceras suggests that beloceratids thrived during oligotrophic periods. (H ouse and others, 1985; pl. 2, figure 11- 12). T he latter is a m arker The chosen stratotype has one of the best know n goni at i te for the P layfordites and N eom anticoceras G enozones (do I-I and I- records around the Frasm an/Fam enm an boundary and is the best J), or for the cordatum Z one (do 113/y) of the classical goniatite know n anyw here for index species occurring in beds exactly at the zonation. Index species for D ivisions I-K so far have only been boundary. H ow ever, it is far from being an ideal am m onoid locality found above the L ow er K ellw asser level in B ed 25b (A rchoceras due to aspects ofp reservation and difficult recovery of large faunas. sp .) and B ed 26b (M anticoceras ado价 nse). The first evidence for T his m isfortune can partly be balanced by the w ide range of other the latest Frasnian C rickites G enozone (do I-L ) com es from B ed goniatite-bearing and easily cof elatable localities nearby in the 26c. A t C ounn ac and neighbouring sections ot the M ont P eyroux M ontagne N oire, w hich supply additional inform ation on strati- N appe a succession of C rickites species can possibly be estab- graphical ranges and occurrences in slightly different facies settings These w ill be docum ented elsew here (B ecker and H ouse, 1994 in lished. A ll early, oft en som ew hat doubtful m em bers of the lineage press). have w horl form s sim ilar to M anticoceras cordatum and m ay be related to the C anadian C rick. cord iform e (M iller). C rick. holzapfeli, the index species of the classical holzapfelt Z one, enters T rilob ites in great profusion in the low er part of B ed M e and continues to B ed 31 g and to the end of the Frasnian. T he apparent patchiness of the U pper Frasnian goniatite record is only to a lim ited extent a A mong bottom-living biotas, trilobites are most frequent and consequence of sam pling bias. C learly tw o different goniatite diversified in the L ate Frasnian strata at C ourniac. O f eight fam ilies

MIDDIZ COUMIAC FORMATION ｝ UPPER COUMIAC FORMATION │ │ F R A S N IA N F A M E N N IA │N │ │ a lb Ic Id le a│ lb Ic Id｝’│a lb Ic a│ lb Ic Id│27│a lb Ic Id｝‘│a lb Ic Id│alb a│户卜Idle｝‘1 9│ a ｝”｝“I d｝ ’ ｝‘｝‘│a lb Ic｝d｝’If │ a│ lb｝c a│lb｝“｝d｝‘│

日．． re co rd │ ││ │

= In ferred││ ran ge │ │

F igure 7 R ange chart show ing the trilobite recordfrom B ed 2 3 to B ed 39 around the G SSP in the section at the Upper Q uan y at C ounziac. M odified from data of R F eist (in F eist, 1990).

[)P r p m h p r 1 9 9 3 4 3 9

know n giobally to he present at the U pper K ellw asser extinction Frasm an. arnom , the benthonic form s. the Frasnian[Faniennian c\cnt (Feist. ］990: 199 1）．Six Occur in the stratotype section boundary is characterized b} a m ajor extinction since 05 per cent of (Pioctidae, A Ulacopleuridae. O dontoplCUridae. H arpetidac, D al- all recorded taxa 山sappear there (L ethiers and Feist. 199 1）．T hus. m anitidae and Phacopidae) and of a total of 13 species know n the C ourniac stratotype bears evidence （）【an extraordinary breadth ,dobaliy, nine are represented at C OLIflu ac (see fi-ure 7). A ll but offaunal representation enabling correlation into re-in-les w ith better three fam ilies and 川 species disappear w ithin Z one 13. or at the spore and acritarch records. T he S D S view s this docum entation as base of the U pper K ellw asser L im estone eqUIValent (B ed 3 ｝9）．T he the best ofany ofthe levels it has recom m ended lot- b0Lm dary strato- latter does not yield any trilobites, nor do the Succeeding beds ofthe types in the D evoin an. L ow er triangtdari.s Zone (B ed 32a-b ), a fact w hich has been observed in all know n Frasm an/ Farnerim an boundary sections w orld w ide. R ecovery does not take place earlier than from the M iddle triangulari,} C hem ostratigraphy Z one onw ards w hen solely phacopids ofthe genus A劝A ratiops occur (B eds 32c-e). T hus the del’ined basal Fam enm an at the base of the A syet geochernical method, do not provide an unairibi2t-IOUS guide Low er triam }iilaris Zone. cannot be precisely recogrused LIS111" to correlation internationally. although there is great potential espe- trilobites. By contrast. the base of the topm ost Frasnian Kellwassei cially w ith strontium isotope chernostratigraphy applied w ithin the Liirc,,tone level can be located w ith considerable precision by the frarnew ork of conodont biostratigraphy (e.g. R uppel and others. m ajor extinction affectin., trilobites at that level (Feist and 1993). G eoclicinical m ethods do. how ever, provide an im portant S ch ind ler, 199 4 ). clue to environm ental interpretation. T he stratotype section at Fine-scale in tr a z onal subdivision and biostratigraphical cori-c- C 011111jac has been investigated for 6 "CI"C values by Joachim ski lation ofthe latest Frasnian at C oLun iac is provided by evolutionary and Buggisch（1993) where：、positive Shift of (3-1 T w as noted at the species of、 the proetid Palpeb，一（dia w hich are characterized by a trend boundarv. Rarc-carth elem ents iR LI--) have been investigated by in reduction of the palpebral lobe and in the straightening of the G randjean-L& Llyer and others （1993) using individual D evonian facial suiures. T he ancestral form , Pal. latepalpebralis beinIg already conodonts, but no anornaly at the boundary w as noted although the present below the Low er K elbvasscr ［finestone cqL]i\alent (B ed R E F patterns did not conform w ith those of m odern sea w ater．T he 24a), has been recovered as hi,,h as in the m iddle of Zone ］3 (B ed pursuit Of it-idillm anom alies has not been Successful at C ounnac 29d). It gIave rise to Pal. palpebralis w hich is abundant 川B eds 3 1。 (G irard and others, 1993), nor at Steinbruch Schm idt (M cG hee and to 3 1 e and is also k no w n froin latest F rasin an sectio ns in the R hen - others, 1984). T hose claim ed at the boundjry in the C anning B asin ish Schicfcr1(,cbfi-gc and H arz (Feist and Schindler, 1994) and m ay have proved to he from a m uch In Lher stratigraphic level (B ecker Occur in the C annim , Basin of W estern A ustralia (K M cN am ara. oral and others, 199 1: N icoll and Playford. 1993) although there is a com m unication) T he last represcritative of the lineage is Pal. bre(－ w eak iridium anonialv apparently at the correct level at X iangtian （ioe v\ hich ciners the stratolype section in Bed 3 1 c and f, thus m ark- (W allg a n d others, 199 1）and other elem ent anom alies, but the cause ing precisely the last oxygenated lcvel-bottoin environm ent prior to is unce rtain . T h ere h as b een no link o f ru icro tek tites w ith the bo u nd - the hypoxic overturn of the U pper K ellw asser Lim estone. T his ary stratotype and records elsew here are higher in the Fam ennian species is at least of m oderate value for long distance correlation as (high w ithin the Low er triangidaris Z one at Senzcillcs in Belgium : it has been recovered in the R henish Schiefergebirge (at Stem bruch C laeys and others, 1992. figure I；L ow er crej)ido Zone in South Schm idt) ai记 in the H arz (A ckc V alley) in an equivalent position C hina: W ang, 1992). and associated there w ith Pali)i atolepis linguUi)rinis (Schindler. 1990). C onsequently Pal. brecciae appears to be lim ited to the low er part of the linguiM i-m is Z one. T his supports the results obtained by R elationship to the U pper K ellw asser E vent graphic correlation, w hich indicated the presence of lingit咖rM IA The m ain sedim entary m arker ofthe G SSP is the top of the distinc- Z one equivalents at C ourniac in B eds 3 If and g (M apper in B ecker tivc level know n in G erm any as the U pper K ellw asser Lim estone and others, 1989, p. 262). (W alliser and others（1989 ). T his dark hypoxic lim estone appears to C oncom itantly w ith th e Palp ebralia line, another evolutionary reD rc se nt a il acm e in th e sm -cad o f a d istinctive 九cie s w h ic h in trend is seen in Succeeding populations of CrYphops acuticeps and m any sections ,Iot)ally is precisely constraineo ny conocioni m os- this trend is of biostratigraphical significance. This group, w hich is tratigraphy. In parallel w ith the w ork of the SD S in recent years has rather com m on in B eds 3 1 a to 3 1 f, exhibits a spectacular reduction been the recognition of an im portant extinction event near the in the inean num ber of its eye lenses w hich drop from ten lenses in Frasnian/Farnennian boundary. Som e of一 these extinctions w ere Bed 3 1 a to only three lenses in B ed 3 1 f before its final extinction listed in the previous sections. T he recom m endation of the Sub- (Feist, 199 1）．This CVOILItion m ay represent ：、further potential foi com m ission for a G SS P falls at a level im m ediately above the acm e tine-scale hiostr atig raphical subdivisions and correlation during a of extinctions. that is at the base of the Low er trionguloris Zone. period of'w orld-w ide biotic crisis. T he m ost precise docum entation for this (Becker and others, 1989) has been follow ed by data assem bled for the Subcom m ission and illustrated here (figures 5- 7). Follow ingI especially the w ork of O ther fossil groups Sandberg and others （1988) this level has been w idely traced inter- nationally. P alynomorphs have been obtained from the Upper Kellwasser level There h a s been m uch debate on the Cause of the sedim entary (B ed 3 1-) but are too badly preserved for precise identification: fur- perturbation represented by the U pper K ellw asser Lim estone. The ther w ork is required here. T he stratigraphically im portant entorno〕- m atter cannot be said to be resolved. Indeed, som e m em bers of the zo accan s are a rathe r m ino r fau na l e lem en t} d etailed w o rk is cu r- Subcom m ission earlier took the view that a m ore appropriate bound- rently being carried out by F L ethiers. Solitary rugose corals, gas- ary m ight be chosen aw ay from the sudden faunal and sedim entary tropods, orthoconic and breviconic nautiloids, crinoids and rare fish changc just below the base ofthe L ow er triangularis Zone but in the scales represent further accessory fossil groups Still to be investi- end, the ease ofinternational con elation based on the faunal changes "ated in detail. B rachiopoda and bivalve records of C Babin and P R led to this boundary being recoi nm et ided. R acheboeut have been presented (in Feist. 1990 ). R ich hornoctenid Four m ain groups of hypotheses hav e b e en invoked to explain faunas have been determ ined by M T ruvols-M assorn (in Feist. the faunal and sedim entary changes around the base of the Low er tri- 1990)} the H oinocienus ultim us Z one is first recognized in Bed 26c angularis Z one. Firstly, causes related to a bolide im pact or inapacts a nd th erefo re see m s to co rrelate w ith the C rick ites G e no zo ne. 0 stra- (Sandber- and others 1989, M cLaren and G oodfellow 1990). Sec- cod data of' F Lethiers have been listed (in Feist, 1990), and m ore ondly, a spread of' anoxic conditions on continental shelves a}soci- than 30 different species are recognised in the topm ost beds of the ated w ith possible tectonic events and ocean overturn (W ilde and

EpisM es, 、初／．I6，，，（，．4 4 4 0

B erry, 1984} B u1ggisch, 199 1）w ith a transgression follow ed by Feist, R , ed ，1990, The Frasnian/Fam ennian boundary and adjaccnt strata ol quick regZ,ression at the Lipper boundary (Sandberg and others, 1988). the eastern M ontague N oire, France: RjG S Subcom m ission on Thirdly. these second events but associated w ith a peak of cold cli- Devonian Stratigraphy, G uide Book, 69 即． inatic conditions, resulting in a rise of' the pycnochne (C opper, 1-cist, R , 199 1，T he late Dcvonian trilobite Crisis: Historical B iology, v. 5, 1986). Fourthly. the sanie, but w ith the U pper K ellw asser Lim estone pp . 19 7--2 14 representing a peak of hot clim atic conditions, resulting also in a rise Feist, R , and Schindler, E-, 1994, Trilobites dt-11-ifli!, the Frasnian KcIlw asser crisis in European Late D evonian cephalopod linicsiones: C ourier of the pycnoclinc and probable disruption ofthe trophic tiering, par- Forschungsinstitut Senckenhcrg, v. 169, 195-223. ticularly that of the plankton (Becker and H ouse. 1994); this latter G irard. C , Rocchia, R , Feist, R , Froget,［一，and Robin, F.. 1993, No cvidence theory w as first invoked for D evonian anoxic events by Becket of im pact at the Frasnian/Fam ennian bOUndarv in the siratotvpc area. （1992). R elated hypotheses involving clim atic w arm ing have been Southern France- Interdisciplinary C onference on G lobal BO、L1ndai\1 suggested by T hom pson and N ew ton （1989) and O rm iston and Fvcins, K ielce, 27-29 Scptc[iibcr 1993. A bstract. K lapper （1992). It is -enerally recognised that the collapse of stro- G oodfe llow , W 「），G eldsetzei, IF IF J, M cL aren, D J, O rchard , M J, and m atoporoid reel'systern s ricar the end of the Frasnian led to extinc- Kk甲per, G , 1989, ']'he Frasnian/Fam ennian extinction- current 1-C.SUI tS tions （）｛’associated faunas. H ouse （1985) has draw n attention to the and possible causes. in M cM illan, N J, Em bry, A F and G lass. 1) J, c(I s. , m any sim ilar events at other levels in the D evonian su,I,gcstiilg that Devonian ‘）｝the W orld: Canadian Societ} （）！Petroleum (w ologists, an interpretation enablinIc, a co m m on hypothesis is to be preferred. M cnioir 14, }. 3, pp. 9--2 1. W hatever the cause(s ) o f this sedim entary perturbation m ay be, G randican, 1'. A lbarede, F. and Feist, R , 1989, R E E N arialio ns acioss the the SD S took the 、iew that the hypoxic perturbations bclo\N the base 1了r是1、111之111／1了之汇lllclllll之川 b o l-I nclarv. Ferra 八hstract、一\. I } pp. 184 of the I-o\x,cr trim igularis Z one resulted in a considcrjbie faunal G randjean-1.6cuyei, P, Feist, R, and A lhai& lc, F, 1993, Rate cat(h clem ents in old biogenic apalitcs: G eochem ica ct (’o ,m oclicinica 八ct } l . v. }7 . 1)p . chant,eover and an horizon w hich m ay be correlated internationally 2 5 0 7 --2 5 14 . w ith perhaps m ore precision than any other in the D evonian. It is in H o u se, M R } 19 8 5 , C o rre latio n o f m id -P ala co z o ic a rn m o n o id c \ o lu i io n a rv the li,,ht ofthis view that C ourniac w as recom m ended for the G SSP events w ith global sedim entarvI perturbations: Nature, Londor,、3 1 ', to deline the base of the Fainennian Sta-c. pp. 17 -22. H OLISC, M R, and K irchgasser, W 下，1993, D evoni；川9‘川latite biOSII-aligraph} and tim ing 〔）｛、tacics m ovem ents in the Fras n i an of R ef e re n c e s eastern N orth A merica, in H ailwood, E".A . and K idd, R 13, eds，H i 0 i RC}011.11[1011 Stratigraphy, Geological Societ} Special Publication, no. 7 0 , f3ccker, R T, 1992, Zur Kernitnis、〔川fie川hCrV-StlIlC Lind A nnulata- I.ondon,pp.267-292 Schiefet im N ordsauerland tO hci-(Ic\on, Rheinisches Schictcrgeb i rg c , House, M R, K firchgasser, Price, J D, all(] W ade, G ,］985. G oniatites hom G K 4611 Hohcnlinnhm ,,): Berliner Gcow issenschal-fliche A hl-randlUng e r Frasniall (U ppe，一Devonian) arid adjacent strata of the M ontagne N oire: F}, \. 30 一pp. 3-4 1 Flercynica.、．］、pp I一］9. Becker, R T} 1993a. Straligraphische G licderrjI12 und A m m onoideen- E Q } 1989, O il tire Fraq ijan/1-anicrinian triass cx tinction e\crit in S outh FA ILICII inn Neh(lenti-1111 (O lv idew n 11) w n FIVIOINI Lind Nord-A l-rik a : ( Intra:（0111 ICI- FOtSCllUl),SlTN itLu Scnclkcnhcq-}. ］7, pp. 2-75-10 1 COLIlicr ForschUngSinStitir Scrickcriberg, v. 155, 405 pp, ,loachim ski, M Nt and B uggisch, W , 1993, A noxic events ill the late Becker, R T, 1993b，八coxia, CILISUItIC changcs, and U pper D c\onian 【（） Frasn}ar--- C auses of the FI飞1，11］an／1了是1lllclllll之tll t au nal crisis: G C010 2 ) ． 、 lowerm ost C arbonitel-OLIS9l obal am m orroid diversity, m H ouse, M R , 21，pp.675-678 cd., The am m orroidea: crivii-oruncin, ccology, and evolutionary change : Klapper,（；，1989, The M ontagne N oire Frasnian (U pper D c}oniajfl Svstelliatic、八ssociation special v. 47, C larendon Press, O xlm d, pp. conodont }LICCCSSIOII, ill M cM i Ilan, N J, Fm hry. A F and G lass, D J } 】15- 16 1 . cds., D evonian ol'thc W orld: C anadian Society of Pelrolcurn G eolog i st s , Becker, R T , Feist, R , Flais. G , H OI.IsC} M R, and K lappcr, G , 1989, M enroir 14, }. 3, pp. 449-468. Frasnian/F am erin ian extincti(川 C}ents in the D eNo rliall al ( (川川 ia c , Klapper, G . and Fo}ter Jr, C T , 1993, Shape analysis of Frasnian specics of southcrn France: Cornple,尽endLIS CIC I'Aca& rnie des Sciences, Pari s , the Late DcNonian conodont vcnus Palm atolepis: Paleontological Scr. 11, \ 下）（ pp. 259--266 Society. M emoir 32 （Journal of Paleontology, v. 67, no. 4. }Llpp.）一 3 -} pp. Becker, R T . and H OLI'Se, M R,IL）94， K e llw asser events and goniatitc Lcthici s,「；，and Feist, R, 1991，La crise des ostracodc} henthiCILIC,} 川 }ticccssions in the M oramune Noire w ith corrunew s on possihlc passage Fja}nicn-F arricnu ian CIC C O LIAlliac (NIontaLlic N o ire, Fian ce C A lSittions: Courier ForschungsinSti(Lit Scrickcriherg, v. 169, pp . 4 5 -77 met idionale): COlnptCS RCFICILIS (IC I’A cadem ic des Sciences, Pal is, S c i. Becke‘一，R T . HOLISC, M R, and A shoUti,／＼R, 1988, Potential s(ratotype 11, v. 3 12, pp. 1057-1063- section lor the Frasnian/1-mirennian hounda", at El Atrous, Talitall. M cG hee Jr, G R , G ilm ore, J S } O rth ,〔一J, and O lsen, F', 1984, N o M o ro c co : D O C LIFYIC ITI SU b m in ed to th e In te rn a tio n a l S U bc o m m iss io n o n gcochernical evidence for all asteroidal im pact at late Fle%onia n r n a}s D evonian Straligraphy, Rennes, 1988- 6 pp. extinction horizon: N aluic, London.、308, pp. 629-63！． Becker, R T. H OLISC, M R, Kiichgas}cr, W 1', and Playford, P F- 1991， M cl-arcn, D J, and G oodl'ellow , W D . 1990, Geological arid hiological Sedimentary and I'aUnal Changes a(ross the Frasnian/Famennian consequences 01 giant im pacts: A nnual Review Farth air(] Plarlelm-y hOUndary in file C anning RaJn ol'W cstcrii A ustralia: 11 istoi ical Sciences. v.］8}pp.123- 17］． Biology, \. 5一pp. 183- 190 N icoll, R S, and PlaNtord, 1) F, 1993, Upper Devonian in山Hill all()Illalics} Becker, R 1, H ouse, M R一and K irchLass以 w 一丁，I99飞，D evonia丁I9olliante co no d o n t zo n aiio n a nd th e F rasn ian /F a m e n n ia n 110 1-Ind arv in tire biostratiD -aphy and tim ing ol'I'acics Illm enlents in the Frjsnian of the Calm ing Hasin- W estern A ustialia: Palaeogeograpliv Canning B am n, W estern Ausualia, in flailw ood, F A , and K idd, R B, PalacoclinlaI0102y, PalaCOCCO]02},、．104, pp. 105-1 1 3 eds., H igh rCSOlUtiOll Stiali2raphy: GeOIO}iCdl SOCICt}l Special Ornliston, A R, and Klappcr, G . 199-2, Paleoclim arc. controk oil Upper Publication, no, 70, pp, 293- ;?-l Devonian IOUrce rock sequences and slacked extinctions： 51h North Branson, E B. and M ehl, M Gi． 1934, C onodonis from the G iassy C reek A merican Paleontological Convention, Abstracts and Program , S h a le 0 1'M ISSO U ri U n iv e rs itv o f M i.}so u ii S tU d IC S, V . 8 , 17 1- 2 59 Paleontological Society Special Publication no. 6, p. 22T jim print 1933 1. Ruppel, S C , Jam es, F W 一and Barrick, J F, 1993, Fligh rc}olfl iO[l strontiLlin BLI,Lisch, W , 1991，T he global Fra}nian/Farricnnian 'Kcllw a}}er Event' isoiopc chem ostratigraphy of'the Paleozoic Using conodonts: G eological G cologische RLindschaU, V. 80/1，pp. 49-72. Society （）｝、A m erica, Abstracts w i山Piogram s, v. 25(6). pp. A 473-474 BUItVIlCk, 1'. Dreescri, R, G roc}sens, F, Struve, W , W eddige, K , W erner, R , Sandberg, C A , Schindler. E ．W alliser, 0 H, and Ziegler, W , 1990, and Zieifler, W , N 88 八rdennes (Belgium ) and Filcl H ill} (Federal Proposal for the Frasnian/Pamennian }It StCiIIIII-Lich SCIIIIIidt (Err .sc a rca, Republic of G erm any): Conner Foi-SCIlLUILSillStitlit Scrickciibcqu, v. 1 0 2- Keller w ald, R hein. Schictergchirge, G erm any) mid m atci ial for the pp. 9- 15 5 corresponding field trip on Septem ber 18, 1990. Docum ent C lac}s, P, Ca.}icl一‘J-G , and M aigolis, S, V , 1992, M ikrotectitcs and m ass (UnpUblishe山subm itted to [tic Subcom m ission on Dcvom a n c\Iinctiolls: C\idcilcc fol；‘Late Devolliall astcloid im pact: Science, V . Stratilgraphy O CS, IUG S), Frankfurt/M , 18 pl). 2}7, pp. 1 102一！川4 Sandberg, C A , Zicl,ler, W , D icc}cn, R, and Butler, J 1- 1988, Late Framuan C opper, P, 1986 Frasnian/Fam ennian m ass extinction all(] cold-Nincr mass extinction: Conodont event straii}lrapfr\, gdolial changes and pos}ibl e ocearis: G eolm -,y, v. 14, pp. 835- 839. caLISCS: COUrier Fot.,,chL inL Sirlsti tilt Senckenherg, v. 102, pp. 263-307

O e c e m b e r /9 9 3 4 4 1

Sannem ann, D , 1955, Beitrag zur U ntergliederung des O berdevons nach W alliser, 0 H , G roos-Uffenorde, H , Schindler, E, and Ziegler, W , O n the Conodonten: N eues Jahrbuch ftir G eologie und Palbontologie, U pper K ellw asser H orizon (B oundary Frasnian/ Fam ennian): Courier A bhandlungen, v. 100(3), pp. 324-331. Forschungsinstitut Senckenberg, v. I 10, pp. 247-255. Schindler, E, 1990, D ie K ellw asser-Krise (hohe Frasne-Stufe, O berdevon): W ang, K , 1992, G lassy m icrospherules (m icrotektites) from an U pper G bttiDger A rbeiten zur G eologic und Paldontologie, v. 46, 115 pp. D evonian lim estone: Science, v. 256, pp. 1547-1550. Scrutton, C T, 1988, Patterns of extinction and survival in Palaeozoic W ang, K , O rth, C J, A ttrep Jr, M , C hatterton, B D E, H ongfei, H , and corals: System atics A ssociation Special V olum e no. 34, pp. 65-88 . G eldsetzer, H H J, 1991, G eochem ical evidence for a catastrophic b io t ic Sorauf, J E, and Pedder, A E H , 1986, Late D evonian rugose corals and the event at the Frasnian/Fam ennian boundary in south China: G eology, v Frasnian/Fam ennian crisis: C anadian Journal of Earth Science. v. 23, p. 19,pp.776-779. 12 6 5 - 12 87 . W ilde, P, and Berry, W B N , 1984, D estabilization of the oceanic density Steam , C W , 1987, Effect of the Frasnian/Fam ennian extinction event on structure and its significance to m arine 'extinction' events: strom atoporoids: G eology, v. 15, pp. 677-679. Palaeogeography, Palaeoclim atology, Palaeoecology, v. 48 , p p . Thom pson, J B, and N ew ton, C R , 1989, Late D evonian m ass extinction: 14 3 - 16 2 . episodic clim atic cooling or w arm ing? in M cM illan, N J, Em bry, A F Ziegler, W , 1962, Taxionom ie und Phylogem e Oberdevonischer and G lass, D J, eds., Devonian of the W orld: Canadian Society of Conodonten und ibre stratigraphische B edeutung: A bliandlun g e n des Petroleum G eologists, M em oir 14, v. 3, pp. 29-34. H essischen Landesam tes f6r Bodenforschung, v. 38, 166 pp. V anguestaine, M , D eClairfayt, T , R ouhart, A , and Sm eesters, A , 1983, Ziegler, W , 1971 , Conodont Stratigraphy oft he European D evonian: Zonation par acritarchs du Frasnien Sup6rieur- Fanm ennian Inf6rie u r G eological Society ofA m erica M em oir 127, pp. 227-284. dans les basSiDs de D inant, N am ur, H erve et C am pine (136vonien Ziegler, W , and Sandberg, C A , 1990, The late Devonian conodont zonation: Supderieur de Belgique): A nnales Soci6t6 g6ologique de Belqique , v . Courier Forschungsinstitut Senckenberg, v. 12 1, 106,pp.121- 171. 115 pp．口

D r G ilbert M apper (top right) is Professor of G eology at the U ni- D r R aim und F eist (bottom right) is D irector of R esearch w ith the versily of I owa, Iow a C ity, Iow a 52242, U SA . H is research concen- French N ational Scientif c R esearch C entre (C N RS) at the U niver- trates on Silurian and D evonian conodont taxonom y and biostratig- sity of M ontp ellier (U STL, 34095 M ontpellier, F rance). H is raphy, w ith sp ecial em phasis on the F rasnian. H e is currently research concentrates on north-G ondwanan trilobite geograp勿， involved w ith m ethods of m orp hom etric analysis of c onodonts and system atics and biostratigraphy. H e is currently analysing the their use in graphic correlation. H e is a Titular M em ber of t he Sub- im pact of g lobal events on late D evonian outer shelf trilobite bio- com m ission on D evonian Stratigrap 勺 and was its Vice-Chairm an jacies, evolution and diversity. H e is V ice-C hairm an of the Sub- from 1976 to 1984. com m ission on D evonian Stratigraphy.

D r R Thom as B ecker (bottom left) w orks at the Palaeontological Institute of the F ree U niversity B erlin (M alteserstraj3e 74-100, B uilding D , 12249 B erlin). H e received his doctorate in 1991, from the R uhr-U niversity of B ochum , G erm any. From 1988 to 1990 he w orked at the U niversity of Southam pton on D evonian extinction events. H is research concentrates on M iddle P alaeozoic am m onoids, high-resolution stratigraphy, sea-levelfl uctuations and the links betw een global environm ental change and evolution in the D evonian. H e is a C orresponding M em ber of t he Subcom m ission on D evonian Stratigrap柳．

P rofessor M ichael R H ouse (top left ) is P rofessor of G eology at the U niversity of S outhamp ton (Southam p ton S0 9 5N H , U K ) and for- m erly of the University of H ull, H e is a former President of the P alaeontological A ssociation, the System atics A ssociation and P alaeontographical Society. H is researches have m ainly concen- trated on m id-P alaeozoic international correlation and regional and event synthesis, m ainly using aninionouls. H e is currently Chairm an of t he Subcom m ission on D evonian Stratigraphy.

r'_F i s odes A rem inder of our address changes, P'_F isodes please tell your colleagu es and friends.

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