Upper Palaeozoic Fusulinid Assemblages, Wandel Sea Basin, North Greenland
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Upper Palaeozoic fusulinid assemblages, Wandel Sea Basin, North Greenland Inger Nilsson Eight fusulinid assemblages are recognized in the Mallemuk Mountain Group of North Greenland. They are of late Moscovian (Wedekindellina assemblage), late Kasimovian (Rauserites ex. gr. simplex assemblage), early-middle Gzhelian (Rauserites ex. gro rossicus assemblage), late Gzhelian - ?early Asselian (Schellwienia arctica assem blage), early Asselian (Sphaeroschwagerina aff. S. vulgaris assemblage), middle-late Asselian (Schwagerina ex. gro nathorsti assemblage), latest Asselian - earliest Sak marian (Schwagerina aff. S. moelleri - S. ex. gro exuberata assemblage) and late Sakmarian (Schwagerina plicatissima assemblage) ages. These assemblages show close similarities to faunas described elsewhere in the present Arctic region, i.e. Arctic Russia, Southwest Barents shelf, Svalbard and Arctic Canada. I. N., IKV Petroleum Research, N-7034 Trondheim, Norway. Present address: Saga Petroleum a.s., Torvet 7, Postboks 1/34, N-940I Harstad, Norway. Biostratigraphical information from most Upper Palae drup Basin of Arctic Canada and eastwards to the Timan ozoic deposits of the Wandel Sea Basin in North Green Pechora Basin of Arctic Russia. Sediments of the Malle land is limited (Fig. l). The zonation of Stemmerik & muk Mountain Group are exposed in Peary Land in Håkansson (1989) is based mainly on biostratigraphic central North Greenland and in Holm Land, Amdrup work of Dunbar et al. (1962) and Petryk (1977), with Land and Prinsesse Ingeborg Halvø in eastern North some additional fusulinid datings by J. E. Whittaker (in Greenland (Fig. 2). They comprise more than 1100 m of Stemmerik & Håkansson, 1989). Additional stratigra shelf carbonates and siliciclastics with subordinate eva phicai information has been provided by Nilsson et al. porites (Stemmerik & Håkansson, 1989; Fig. 2). Deposi (1991) based on a few fusulinid bearing samples from tion probably occurred in small, isolated fault-blocks Peary Land, Prinsesse Ingeborg Halvø and Amdrup Land separated from the stable Greenland craton by major fault (Fig. 2). Five fusulinid faunas of late Moscovian, Gzhe zones during the Moscovian and on a more widespread lian, middle-late Asselian, late Asselian - ?early Sak shelf during late Carboniferous - early Perrnian times marian and late Sakmarian ages were reported. (Håkansson & Stemmerik, 1984; Stemmerik & Håkans• No documentation of fusulinid faunas has been pub son, 1991; Stemmerik & Worsley, 1989). lished from this region, apart from one paper dealing with The Mallemuk Mountain Group comprises three for fusulinids from Holm Land and Amdrup Land (Ross & mations: the Kap Jungersen Formation, the Foldedal For Dunbar, 1962). This paper documents the fusulinid fau mation and the Kim Fjelde Formation. Early Moscovian nas presented by Nilsson et al. (1991) and discusses their shelf deposits ofthe Kap Jungersen Formation are present biostratigraphical relevance to the adjacent areas of Spits in the southern Holm Land and southern Amdrup Land bergen, Bjørnøya and Barents Sea (Finnmark Platform) blocks (Fig. 2). The base of this formation is, however, (Fig. 1). In addition, it includes re-examination of the diachronous as the formation onlaps an irregular mid fusulinid material described by Ross & Dunbar (1962) Carboniferous relief. Late Moscovian to Gzhelian shelf from Holm Land and Amdrup Land (the Pseudoschwa deposits of the Kap Jungersen and Foldedal Formations gerina zone of Dunbar et al., 1962) and Petryk's (1977) were far more widespread covering Holm Land, southern material from eastern Peary Land. Amdrup Land, most of Peary Land and possibly also Prinsesse Ingeborg Halvø (Stemmerik & Håkansson, Geological framework 1991). During the late Carboniferous the mixed silic iclastic and carbonate deposits were succeeded by rather During the Late Palaeozoic North Greenland, together uniform deposition of shallow water carbonates of the with the Barents Shelf region, formed part of a sedi Kim Fjelde Formation (Fig. 2). A continuous carbonate mentary basin which connected westwards to the Sver- platform was gradually developed along the entire 1ength Rapp. Grønlands geol. Unders. 161, 45-71 (1994) © GGU, Capenhagen, 1994 46 Fig. l. Locality map in 110lth polar projection silOwing Norlh Greenland (Wandel Sea Basin). Svalbard (including Bjørnøya). W and SE Barellls Sea (Finnmark Platform) and Timan-Pechora 8asin af North Russia. af tile \Vandel Sca Basin (Stcmrnerik & Håkansson, zel1oel/o Iibrol'ilC!Ji (Dutkevieh). Bea/eina paradistenta 1989). Shallov,:ing condilions took placc during tile Early (Safonova) and Fuset/inella cf. F backi MolJer (Nilsson d Permian mainl)' in AmJrup Land while the derositiona! al., 1991: Fig. 3). This fauna closeJy resembles the fauna basin apparently became gradually cleeper during Ille ol' the up per !v1oscovian Wedeki/ldel/ina zone af Dunbar same time in Peary L.and <:Ind Prinsesse Ingeborg lIalvø el al. (1962) from Holm Land and Amdrup Land, and (Stclllmerik & Håkansson, J991). tllus suggests an age ulder than previously proposcd for the lower pan ol' the Kim Fjelde Formation in Ihis area Fusulinid assemblages (cL Stemmerik & Håkansson, 1989). Onc sample (GGU 221337) eollccted in northern AIll FusuJinid bearing samples from severaJ scctions ol' dru]) Land contai ns poorly preserved specimcns or the North Greenland have bcen invesligated and eighl loeal genus F/lsl/iil/cl/a (Nilsson et al., 1991; Fig. 3). Tilis assemblages have becn rccognized (Fig. 3). Tlle faunas indic;,llCS aMiddie Carbonircrous. possibie late Moseo have been compared with faunas in stratoLype areas of (Ile vlun uge for lllese sediments which previousty were be Russian Platform and Urals and lO faunas elsewhere in tieved to bc of Enrly Permian age (cf. Stemmerik & Ille Arctic region (Fig. 4). Håkansson. 1989). Wedekinde!!ina asselllblage (Iate Moscovian) RaL/ser/les ex. gro simplex asselllblage (Iate Kasilllovian) Sample GGU 221386 from the Kim Fjelde Fonllatiol1 in soulhern Amdrup Land (Fig. 2) comprises Wedekindel Fusutinids or Late Carboniferous age ('Triticitcs' spp. lilla duJkell;chi R,IUScf-Chcrnousovll & BeJyLle .... , Taj!- and Pseu{/(4il5ldineJ/a spp.) have preyjously been re- 47 pOrLeJ from eastern Pearl' Land (Petryk, 1977; Stcmll1C simplex (Sehcllwien), and the Pseodn.lil."iulincllu spp. be rik & Håknnsson. ]989). Re-cxamination ol" Pctryk's col 10ngs to the PselldoIlIsll1i1lel1a usvae gruup (Fig. 3). leetions from the Foldedal Formation shmvs thilt the PselldofilslIlinella usvae (Duktcvich) is long-ranging, 'Triticites' fauna in the ]ower p<ln of the section are marc occurring in Upper Carboniferous strata as \vell as in primiLive Lhan Lhose from the upper part. The assemblage Lower Pcnnian beJs. Rauserites silllplex (Schelhvien), or 'Triticiles' spp. in the samples 171. 172. 175 and !82 howevcr. has <l more restricted stratigraphi<.: occurrence. (sec Pdryk, [977) are here assigned LO f?ollseriles e;", gI'. It is presenl in up per Kasirnovian 10 ]ower Gzhelian Slrata 82' I z z w, z< ", ~ii :5 [;i >< "<-" MIDNATF'JELD • .?" FORMATION ----?- (Pcary Land only) z z z< ~~ ~ii n .,<. wo Ww Wz Øo • <7 KIM FJELDE ----------?--- FORMA lION GGU 22086 z ~ ~---------------E'!9-------1 ~ GGU 196343 O. GI 72168 '0 " /O GI 72371 ~~ FOLDEDAL ~~ -'-'-d GI 12370 I ? I FORMATION ~~ "'--------1 ~ KIl,P JUNGERSEN !!! FORMATION ~~-------- pnlNseSSE S HOLM LAND N. HOLM LAND S. AMDRUP LAND N AMDRUP LAND INGEBORG HALVØ E. PEARY LAND BLOCK BLOCK 8LOCK BLOCK BLOCK BLOCK Fig. 2. Lithoslratigraphic cor're1alioll af marine Upper Palaeozoic .\ediments in No]"lh Greenlano wirh position of the fusulinid bearing samples. Solid Jines indicatc lilhostraligraphic units: dotted line suggested biostr<ltigraphic correlalion by Stemmerik & Håk;:wsson (lY~9). [ll~el Illap shows distrihutiol1 ol' Upper Palacozoic sediments. From Nilsson er al. (199!). 48 assemblages age 1lO"'" Schw. p1lca1isg.lma---."s~"}"~~a~":~<i;;;n=ano;c~-1 - 1.~ --1/1",.. Schw. aff. moollari - lal8 Asselian _ ",n'" SChw. eX.gr. exuberata ? early Sakmarian '§ '" • ,,~ ------I';. ,~ Schw. eX,gr. nalhorsli m. -I. AsseHan 0117'1"·" ~ "~, Sphaeroschwag8rina n-"~ early Assa/ian att. vulgaris "",," ~twie,nia arcti]·ii.:=+JJ,,"~I~~]''i:.]A",,~I. --- _,o RaUS8,ites sarly· mlddle _'o_.. ex. gr. rossicus Gzhelian -,~ Ol n,.. "'''.m ;o 1~10 _,el Rauserites lals '" eX,gr. simplex Kasimovian -_,o_'" """111 ~'JM oou Wedekindellina lals Moscovian 00tJ:>:l"'" Fig. :1. COlllposite-distribution chart af fusulinid species from Nonh Greenland.. = loose blod. in tne Russian Platform (Rosovskaya. J 958) and lhe lIpper Gzhclian beds (Rauser-Chernollsova et (Il.. 1979). Urals (Davydov in Chuvashov et af., 1986) while only Ql/{lsifllslllina? sp. and RlIgosQ.(us//!iI/({ art". l? diplica Lhis species is common in upper Kasimuvian beds af Rosovskaya occur in thc same leveIs as RauscrilCS ex. gr. Spitsbergen (in the Ral/seriles qllClsial'cticlfs zone ol' Nils I"Ussicl/s (Schellwien) (Fig.3). Duc to Jack af Iypical up~ son & Davydov, 1993). per CJ7.helian fusulinic1s Ihe asselllblage is suggested as In the Peary Lmd seclion lhe Rauserires ex. gI'. .rimp/ex bcing ol' carly-mide/le Gzhelian age. asselllblage is overlain by the Rauseriles ex. gr. rossicl/s Sample GGU 196343 from [he upper part of the Folde assemblage, indicating early-middle Ozhelian age (see dal Formation in eastern Pcary Land contains Ral/saites discussion belo\v). No distinct lower Gzhelian fauna oc rossicl/.s (Schcllwien). Rugosojusl/lina? sp., QuasUilsu