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Early Frasnian (Late Devonian) Radiolarians from the Kamenev Formation, Rudny Altai, Russia
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RODINIA, GONDWANA AND ASIA
Ueno, K. (1999) Gondwana/Tethys divide in East Asia: solution from Late Paleozoic foraminifera1 paleobiogeography. In: Ratanasthien, B. and Rieb, S.L. (Eds.), Proc. Intern. Symp. Shallow Tethys 5. Dept. Geol. Sci., Chiang Mai Univ., Chiang Mai, pp. 45-54. Ueno, K. and Hisada, K. (1999) Closure of the Paleo-Tethys caused by the collision of Indochina and Sibumasu. Chikyu Monthly, v. 21, pp. 832-839 (in Japanese). Ueno, K. and Igo, H. (1997) Late Paleozoic foraminifers from the Chiang Dao area, northern Thailand: geologic age, faunal affinity, and
paleobiogeographic implications. Prace Panst. Inst. Geol., v. 157, pp. 339-358. Wang, X.D., Ueno, K., Mizuno, Y. and Sugiyama, T (2001) Late Paleozoic faunal, climatic, and geographic changes in the Baoshan block as a Gondwana-derived continental fragment in Southwest China. Palaeogeogr. Palaeoclimatol. Palaeoecol., (in press). Wu, H.R., Boulter, C.A., Ke, B.J., Stow, D.A.V. and Wang, Z.C. (1995) The Changning-Menglian suture zone; a segment of the major Cathaysian-Gondwana divide in Southeast Asia. Tectonophys., v. 242, pp. 267-280.
Early Frasnian (Late Devonian) Radiolarians from the Kamenev Formation, Rudny Altai, Russia M. Umedal, K. Iwata2,O.T. Obut?, N.V. Sennikov3, N.G. Izokh3and V.D. Ermikov3
' Department of
Earth Science and Astronomy, University of Tokyo, Komaba, Meguro, 153-8902 Tokyo, Japan Department of Earth and Planetary Sciences, Graduate School of Hokkaido University, Kita-ku Kita 10-Jo Nishi 8 Ckome, 060-081 0 Sapporo, Japan United Institute of Geology, Geophysics and Mineralogy, Academy of Science, Siberian Branch, Novosibirsk, Russia ,,,.
The Devonian was a period of the most extensive reef development with a decline in the Late Devonian. The Late Devonian extinction in reef habitats occurred in 2 steps at the Middle/Late Devonian (G/F) boundary and at the Frasnian/ Famennian (F/F) boundary. A significant extinction event of radiolaria, a major zooplankton group with siliceous skeleton, occurred at the F/F boundary, however, information on radiolarians around the G/F boundary is poor. In order to elucidate the response of radiolaria to the G/F event, the authors reinvestigated the Kamenev Formation in the Rudny Altai Mountains that yielded the most precisely dated early Frasnian radiolarian assemblage. The Kamenev Formation which is distributed in the northwestern border of the Rudny Altai Mountains comprises conglomerates, volcanic rocks, tuffs, limestones and siltstones. The lower part of this formation yields ammonoids (Tamarites, Trianoceras, Pharciceras) ,corals (Thamnopora boloniensis, 'Th. reticulata, Alveoliotes levis, etc.), brachiopods (Productella, Spiatripina) and conodonts (Klapperina disparlis, Polignathus ovatinodosus), indicative of late Givetian (late Middle Devonian). The middle part includes ammonoids (Trianoceras, etc.), corals (Thamnopora, Alveoliotella, etc.), brachiopods and
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trilobites. The upper part yields corals (Thamnopora boloniensis, Crassialveoliolitesobtortus, etc.) ,brachiopods (Adolfia laevigata, Cyrtina tricuerta, etc.), conodonts (Anvyrodella lobata, Apathognathus porcata, Palmatolepis punctata, P. levis), pelecypoda (Posidonia mesacostalis, Buchiola conversa), and ammonoids (Manticoceras bullatum, M. spinosum, M. drevermanni, M. carinatum), indicative of the punctata zone (early Frasnian, 367.5-367 Ma) of standard conodont zone. Abundant well-preserved radiolarians were extracted from the black and dark-gray mudstones and acidic tuffs of the upper part of the Kamenev Formation (lower Frasnian) at the Zolotukha and Gryazhukha River sections. The radiolarian fauna is characterised by the dominance of Entactiniidae (Trilonche and Palaeoscenidium, more than 90% proportion) with rare Albaillellidae (Ceratoikiscum and Circulaforma) . These radiolarians and faunal composition are similar to those of the Givetian. This suggests that no remarkable faunal change of radiolarians occurred at the G/F boundary. No major faunal change of other planktonic biota such as chitinozoans and ostracods is known from the G/F boundary. Although the benthic records suggest a major crisis at the G/F boundary, turnover of marine planktonic biota was not remarkable.
Gondwana Research, V 4, No. 4,2001
RODINIA, GONDWANA AND ASIA
Ueno, K. (1999) Gondwana/Tethys divide in East Asia: solution from Late Paleozoic foraminifera1 paleobiogeography. In: Ratanasthien, B. and Rieb, S.L. (Eds.), Proc. Intern. Symp. Shallow Tethys 5. Dept. Geol. Sci., Chiang Mai Univ., Chiang Mai, pp. 45-54. Ueno, K. and Hisada, K. (1999) Closure of the Paleo-Tethys caused by the collision of Indochina and Sibumasu. Chikyu Monthly, v. 21, pp. 832-839 (in Japanese). Ueno, K. and Igo, H. (1997) Late Paleozoic foraminifers from the Chiang Dao area, northern Thailand: geologic age, faunal affinity, and
paleobiogeographic implications. Prace Panst. Inst. Geol., v. 157, pp. 339-358. Wang, X.D., Ueno, K., Mizuno, Y. and Sugiyama, T (2001) Late Paleozoic faunal, climatic, and geographic changes in the Baoshan block as a Gondwana-derived continental fragment in Southwest China. Palaeogeogr. Palaeoclimatol. Palaeoecol., (in press). Wu, H.R., Boulter, C.A., Ke, B.J., Stow, D.A.V. and Wang, Z.C. (1995) The Changning-Menglian suture zone; a segment of the major Cathaysian-Gondwana divide in Southeast Asia. Tectonophys., v. 242, pp. 267-280.
Early Frasnian (Late Devonian) Radiolarians from the Kamenev Formation, Rudny Altai, Russia M. Umedal, K. Iwata2,O.T. Obut?, N.V. Sennikov3, N.G. Izokh3and V.D. Ermikov3
' Department of
Earth Science and Astronomy, University of Tokyo, Komaba, Meguro, 153-8902 Tokyo, Japan Department of Earth and Planetary Sciences, Graduate School of Hokkaido University, Kita-ku Kita 10-Jo Nishi 8 Ckome, 060-081 0 Sapporo, Japan United Institute of Geology, Geophysics and Mineralogy, Academy of Science, Siberian Branch, Novosibirsk, Russia ,,,.
The Devonian was a period of the most extensive reef development with a decline in the Late Devonian. The Late Devonian extinction in reef habitats occurred in 2 steps at the Middle/Late Devonian (G/F) boundary and at the Frasnian/ Famennian (F/F) boundary. A significant extinction event of radiolaria, a major zooplankton group with siliceous skeleton, occurred at the F/F boundary, however, information on radiolarians around the G/F boundary is poor. In order to elucidate the response of radiolaria to the G/F event, the authors reinvestigated the Kamenev Formation in the Rudny Altai Mountains that yielded the most precisely dated early Frasnian radiolarian assemblage. The Kamenev Formation which is distributed in the northwestern border of the Rudny Altai Mountains comprises conglomerates, volcanic rocks, tuffs, limestones and siltstones. The lower part of this formation yields ammonoids (Tamarites, Trianoceras, Pharciceras) ,corals (Thamnopora boloniensis, 'Th. reticulata, Alveoliotes levis, etc.), brachiopods (Productella, Spiatripina) and conodonts (Klapperina disparlis, Polignathus ovatinodosus), indicative of late Givetian (late Middle Devonian). The middle part includes ammonoids (Trianoceras, etc.), corals (Thamnopora, Alveoliotella, etc.), brachiopods and
"-
trilobites. The upper part yields corals (Thamnopora boloniensis, Crassialveoliolitesobtortus, etc.) ,brachiopods (Adolfia laevigata, Cyrtina tricuerta, etc.), conodonts (Anvyrodella lobata, Apathognathus porcata, Palmatolepis punctata, P. levis), pelecypoda (Posidonia mesacostalis, Buchiola conversa), and ammonoids (Manticoceras bullatum, M. spinosum, M. drevermanni, M. carinatum), indicative of the punctata zone (early Frasnian, 367.5-367 Ma) of standard conodont zone. Abundant well-preserved radiolarians were extracted from the black and dark-gray mudstones and acidic tuffs of the upper part of the Kamenev Formation (lower Frasnian) at the Zolotukha and Gryazhukha River sections. The radiolarian fauna is characterised by the dominance of Entactiniidae (Trilonche and Palaeoscenidium, more than 90% proportion) with rare Albaillellidae (Ceratoikiscum and Circulaforma) . These radiolarians and faunal composition are similar to those of the Givetian. This suggests that no remarkable faunal change of radiolarians occurred at the G/F boundary. No major faunal change of other planktonic biota such as chitinozoans and ostracods is known from the G/F boundary. Although the benthic records suggest a major crisis at the G/F boundary, turnover of marine planktonic biota was not remarkable.
Gondwana Research, V 4, No. 4,2001