Polychronous formation of the ophiolite association in the Tekturmas zone of Central Kazakhstan inferred from geochronological and biostratigraphic data

Pleiades Publishing Ltd - Tập 472 - Trang 26-30 - 2017
K. E. Degtyarev1, T. Yu. Tolmacheva2, A. A. Tretyakov1, A. B. Kotov3, A. S. Yakubchuk1, E. B. Salnikova3, Kuo-Lun Wang4
1Geological Institute, Russian Academy of Sciences, Moscow, Russia
2Karpinskii All-Russia Geological Research Institute (VSEGEI), St. Petersburg, Russia
3Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences, St. Petersburg, Russia
4Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan

Tóm tắt

Plagiogranites and conodonts from chert intercalations in basalts of the ophiolite association in the Tekturmas zone of Central Kazakhstan were subjected to the U‒Pb geochronological and stratigraphic investigations, respectively. The age of plagiogranite crystallization is estimated to be 489 ± 8 Ma corresponding to the stratigraphic interval spanning from the uppermost Upper Cambrian to the lower Tremadocian. Conodonts from cherts of the Kuzek Formation are distributed along the section interval from the uppermost part of the Darriwilian (Middle Ordovician) to the lower part of the Sandbian (Upper Ordovician), which corresponds to the period of 457‒460 Ma. It is revealed that the formation of the ophiolite section in the Tekturmas zone was a multistage process lasting from the Late Cambrian to the initial Late Ordovician.

Tài liệu tham khảo

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