Abstract: Late Paleozoic to Recent Development of Sedimentary Basins on the Turan and South Kazakh Platforms, Central Asia

J. C. Thomas, P. R. Cobbold, V. S. Shein, S. Le Douaran

For an area including the North Caucasian, South Caspian, North Ustyurt, Chu-Sarysu, Amu Darya, Syr Darya, Fergana and Afghan-Tajik basins, we have digitized and analyzed structure-contour maps, provided by VNIGNI and based on borehole, seismic and gravity data. The key maps show (1) top crystalline basement, (2) top Permo-Trias, (3) top Jurassic, (4) near top Cretaceous, (5) top Paleocene and (6) top mid-Pliocene.

The Permian suture of the Ural-Turkestan ocean has a long history of activity. SW of it, detrital sediments accumulated within continental rifts up to the mid-Jurassic. Late Jurassic carbonates and evaporites formed in a tectonically quiet setting. In the early Cretaceous, weak inversion, due to compressional tectonics in Afghanistan, led to an influx of sands from the SE. In the Paleocene, strong inversion followed collision of India and Arabia with Eurasia. Erosion of newly-formed relief led to rapid rates of sedimentation in the Neogene.

AAPG Search and Discovery Article #90956©1995 AAPG International Convention and Exposition Meeting, Nice, France