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Acritarchs from the Lower Cambrian Buen Formation in North Greenland GEUS Report File No

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Acritarchs from the Lower Cambrian Buen Formation in North Greenland GEUS Report File No Acritarchs from the Lower Cambrian Buen Formation in North Greenland GEUS Report file no. 22316 Gonzalo Vidal and John S. Peel GRØNLANDS GEOLOGISKE UNDERSØGELSE Bulletin 164 1993 GRØNLANDS GEOLOGISKE UNDERSØGELSE Bulletin 164 o Acritarchs from the Lower Cambrian Buen Formation in North Greenland .. ~ ~ f) Gonzalo Vidal and John S. Peel 1993 Vidal, G. & Peel, J. S. 1993: Acritarchs from the Lower are particular1y important and relevant with classical Cambrian Buen Formation in North Greenland. Bull. Lower Cambrian rock successions in Baltoscandia, vari­ Grønlands geol. Unders. 164, 35 pp. ous areas of the East European Platform, Svalbard, Scotland and North-East Greenland. In all, the reco­ vered acritarch assemblage conclusively confirms the AcritafGhs (organic-walled phytoplankton) are de­ previously proposed late Ear1y Cambrian age for the scribed from the siliciclastic rocks of the Buen Forma­ Buen Formation, most likely corresponding to the He­ tion. A total of 52 form taxa are reported from a small liosphaeridium dissimilare - Skiagia ciliosa (= Vergale number of extremely fossiliferous samples from the 'horizon') and perhaps the Volkovia dentifera - Lie­ deeper shelf portion of the formation. The preservation paina plana (= Rausve 'horizon') acritarch zones in the of acritarchs is excellent and, in the light of their abun­ East European Platform and counterparts in Baltoscan­ dance, the taphonomy and palaeobiology of the Buen dia. Formation are discussed. Three new acritarch form taxa are erected and two more., obviously also new, are left under open nomenclature. Large-size acanthomorphic Authors' addresses: acritarchs represented by extremely rare finds of two G. V., Institute of Earth Sciences - Micropalaeontol­ new taxa (Comasphaeridium? densispinosum n. sp. and ogy, Uppsala University, Norbyvagen 22, S-751 22 Comasphaeridium longispinosum n. sp.) are recorded Uppsala, Sweden. for the first time in Lower Cambrian strata. Large acan­ J. S. P., Geological Survey of Greenland, øster Vold­ thomorphs are otherwise important in Neoproterozoic gade 10, DK-1350 Copenhagen K, Denmark. Present strata and the significance of the present finds is dis­ address: Institute of Earth Sciences - Dept of Historicai cussed. The remaining acritarchs are known from nu­ Geology and Palaeontology, Uppsala University, Nor­ merous wor1d-wide earlier occurrences. Comparisons byvagen 22, S-751 22 Uppsala, Sweden. Grønlands Geologiske Undersøgelse Ujarassiortut Kalaallit Nunaanni Misissuisoqarfiat Geological Survey of Greenland The Geological Survey of Greenland (GGU) is a research institute affiliated to the Mineral Resources Administration for Greenland (MRA) within the Danish Ministry of Energy. As with all other activities involving the non-living resources in Greenland, GGU's investlgations are carried out within the frarnework of the policies decided jointly by the Greenland Home Rule Authority and the Danish State. © GGU, Copenhagen, 1993 ISSN 0105-3507 Contents Dansk sammendrag - Imaqarnersiuineq ., ............ 4 Goniosphaeridium ~p. A. ......................... 23 Introduetion. .................................. 5 Goniosphaeridium varium (Volkova, 1969) Geological framework .............................. 5 Downie, 1982 ................................. 23 Sample register. ................................... 7 Goniosphaeridium volkovae Hagenfeldt, 1989 ....... 25 Material and methods .............................. 9 Granomarginata squamacea Volkova, 1968. ......... 25 Acritarch preservation. ............................. 9 Heliosphaeridium sp. ............................. 25 Taphonomy and palaeobiology 9 Heliosphaeridium coniferum (Downie, 1982) Large acanthomorphic acritarchs. .................... 11 Moczydlowska, 1991 .. ......................... 25 Biostratigraphy .................................... 12 Heliosphaeridium dissimilare (Volkova, 1969) Conc1usions ....................................... 13 Moczydlowska, 1991 ........................... 25 Taxonomy 15 Heliosphaeridium lubomlense (Kirjanov, 1974) Archaeodiscina umbonulata Volkova, 1968. ......... 15 Moczydlowska, 1991 ........................... 25 Asteridium Moczydlowska 1991. ................... 15 Heliosphaeridium notatum (Volkova, 1969) Moczydlowska, 1991 ........................... 25 Asteridium lanatum (Volkova, 1969) Moczydlowska, 1991 .. ......................... 15 Heliosphaeridium obscurum (Volkova, 1969) Asteridium ordensis (Downie, 1982), comb. nov. .... 15 Moczydlowska, 1991 .. ......................... 27 Asteridium tornatum (Volkova, 1968) Leiosphaeridia Eisenack, 1958 emend. Downie & Moczydlowska, 1991 ........................... 17 Sarjeant, 1963. ................................ 27 Leiovalia tenera Kirj anov, 1974. ................... 27 ?Celtiberium geminum Fombella, 1977. ............. 17 Lophosphaeridium dubium (Volkova, 1968) Comasphaeridium sp. A Downie, 1982 ". .. .. .. .. .. 17 Moczydlowska, 1991 ........................... 27 Comasphaeridium agglutinatum Moczydlowska, 1988. 19 Lophosphaeridium tentativum Volkova, 1968 ........ 27 Comasphaeridium mackenziana Baudet, Aitken & Vanguestaine, 1989 19 Lophosphaeridium truncatum Volkova, 1969 ........ 27 Lophosphaeridium sp. ............................ 29 Comasphaeridium molliculum Moczydlowska & Vidal, 1988. ................................... 19 Multiplicisphaeridium dendroideum Comasphaeridium? densispinosum Vidal n. sp. .. .... 19 (Jankauskas, 1976). ............................ 29 Pterospermella Eisenack, 1972. .................... 29 Comasphaeridium longispinosum Vidal n. sp. 19 Retisphaeridium dichamerum Staplin, Jansonius & Comasphaeridium strigosum (Jankauskas) Downie, 1982 .,. .............................. 21 Pocock, 1965. ................................. 29 Skiagia Downie, 1982 '" . .. .. .. 29 Comasphaeridium cL strigosum (Jankauskas) Downie, 1982 ................................. 21 Skiagia ciliosa (Volkova, 1969) Downie, 1982 ....... 29 Cymatiosphaerapostii (Jankauskas, 1976) Skiagia compressa (Volkova, 1968) Downie, 1982. ... 29 Jankauskas, 1979 .............................. 21 Skiagia orbiculare (Volkova, 1968) Downie, 1982. ... 31 Cymatiosphaera sp. 21 Skiagia ornata (Volkova, 1968) Downie, 1982 ....... 31 Dictyotidium Eisenack, 1955 emend. Staplin, 1961 ... 21 Skiagia scottica Downie, 1982 ..................... 31 Dictyotidium perforatum Vidal n. sp. ............... 21 Tasmanites bobrowskae Wa:i:ynska, 1967 .. .......... 31 Elektoriskos sp. A............................... 23 Tasmanites tenelIus Volkova, 1968. ................. 31 Fimbriaglomerella Loeblich & Drugg, 1968 23 Tasmanites volkovae Kirjanov, 1974.. .. .. .. .. .. 31 Globosphaeridium cerinum (Volkova) Trachysphaeridium timofeevi Vidal, 1976............ 31 Moczydlowska, 1991 ... :. ...................... 23 Acknowledgements ................................ 33 Goniosphaeridium primarium (Jankauskas) References. ....................................... 33 Downie, 1982 ................................. 23 Dansk sammendrag Dette arbejde beskriver acritarcher (fytoplankton forekomster verden over. Det er især vigtigt at sammen­ med organisk væg) fra Buen Formationen (nedre Kam­ ligne med de klassiske aflejringer fra nedre Kambrium i brium) i Nordgrønland. I alt rapporteres der om 52 Baltoscandia, forskellige områder på den østeuropæiske arter fra få men særdeles fossilrige prØver, der repræ• platform, Svalbard, Skotland og Nordøstgrønland. senterer den dybere del af shelfen i Buen Formationen. Acritarch-sammensætningen bekræfter fuldtud den ti­ På baggrund af det store indhold af velbevarede acri­ dligere foreslåede datering af Buen Formationen til den tarcher diskuteres formationens tafonomi og palæobio• sene del af tidlig Kambrium, højst sansynligt svarende logi. Tre nye arter af acritarcher opstilles, mens to til Heliosphaeridium dissimilare - Skiagia ciliosa (= andre, tydeligvis også nye, placeres under åben nomen­ Vergale 'horizon') og måske Volkovia dentifera - Lie­ klatur. Store acantomorfe acritarcher er for første gang paina plana (= Rausve 'horizon') acritarch-zonerne på registreret i lag fra nedre Kambrium. Disse former er den østeuropæiske platform og tilsvarende zoner i Bal­ ellers kun beskrevet fra neoproterozoiske aflejringer. toscandia. De resterende acritarcher kendes fra talrige tidligere Imaqarnersiuineq Nalunaarusiami uvani imaani naasuaqqat, acritarchit, taamaattut ujaqqani pisoqaanerusuni taamaallat siorna­ Avannaarsuani ujaqqani immikkoortuni Buen Forma­ tigut allaaserineqartarsimagamik. Acritarchit sinneri si­ tionimeersut ukiut immikkoortut Kambriumip aallartin­ larsuarmi ujaqqani allarpassuarni siornatigut allaatigi­ nerani pinngorsimasut eqqartorneqarput. Ujaqqani neqarsimasuni ilisimaneqarput. Ujaqqat architarchiqar­ amerlanngikkaluartutuni naasuaqqanilli ujaranngorsi­ fiusut pingaarnerit 570 milliunit missaanni masunik amerlaqisunik akulinni, architarchit immik­ pisoqaassusillit Baltoscandiami, Europami kangilliup koortut 52-t siumorneqarsimapput, taakkulu Buen For­ nunavissuani, Svalbardimi, Skotlandimi Tunumilu mationip atsinnerusortaani nassaarineqarsimapput. Ar­ Avannaarsuani sanilliussallugit pingaartorujussuuvoq. chitarcherpassuit ujaranngorsimagaluarlutik ilusaat Architarchit assigiinngitsorpassuit ataatsimoortut tunn­ allanngorsimanngitsut tunngavigalugit qangarsuaq sumi gavigalugit ujaqqat imikkoortut Buen Formationip piso­ inuusimanerat eqqartorneqarpoq. Architarchit immik­ qaassusaasa Kambriumip aallartinnerani pinngorsima­ koortut nutaat pingasut suunerat aalajangerneqarsima­ sutut
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