Sequence Lithofacies Paleogeography of Ordovician in Tarim Basin

Key words: 
• sedimentary facies

Abstract: Based on sedimentary facies observation of many wells cores and outcrops, seismic sequence interpretation and seismic facies analysis, synthesizing the regional geological data such as ophiolitemelange and plate tectonic evolution, it's first worked out the 8 lithofacies paleogeography maps of Ordovician in Tarim basin under the sequence stratigraphy framework (Fig.1, Fig.2, Fig.9 to Fig.12, Fig.16 and Fig.17), and found the 5 isolated carbonate platforms (Northern Tarim Platform, BaChuCentral Tarim Platform, Western LuoBuBo Platform, Southern Tarim Platform, KuLuKeTaGe Platform) of Ordovician in Tarim plate and the basins between them, it's very important to marine oil & gas exploration in Tarim basin. The continental riftogenesis initially developed at the northern margin of Tarim plate in Cryogenian and Early Cambrian, and the tensional stress tectonic environment from Late Neoproterozoic to Middle Ordovician, controlled the formation of several isolated carbonate platforms and the deep water sedimentation areas between them in Tarim plate, otherwise, the collision compressional movement developed between A'ErJin arc, KuDi arc and Tarim plate at the south margin of Tarim in Late Ordovician and abundance terrigenous clasts produced by the collision, brought on gradually disappear of isolated carbonate platforms and the formation of turbidite sedimentary basins distributed in the southern Tarim.