Oligo-Mioence Depositional Facies of the Wuyu Basin, Southern Tibetan Plateau

The Wuyu Basin, southern Tibetan Plateau is one of presental basin of India-Eurasia collision, a continuous sedimentary record throughout Oligocene to Miocene was discovered in the Wuyu Basin and considered as the most integrated Oligo-Miocene record within the Tibetan plateau, observed so far. The sedimentary include the Paleo-Eocene Linzizong Group (include the Dianzhong Formation, Nianbo Fm. and Pala Fm.) and the Oligo-Miocene Rigongla Fm., the Miocene Mangxiang Fm., the Miocene Laiqin Fm., the Pliocene Wuyu Fm., the Plio-Pleistocene Dazi Fm., with a total thickness of 4180m.The Linzizong Gr. composed chiefly of intermediate-acid lava, its middle part intercalated with brownish grey clastic sediment. The Oligo-Miocene Rigongla Fm., is the sediment of intermountain basin, consists mainly of reddish brown sandstone and conglomerate, intercalated with lava. The Miocene Mangxiang Fm. is the sediment from fluvial facies to lacustrine facies, swamp, chiefly grey, dark grey sandstone, siltstone, and mudstone, with coal and oil shale. The Miocene Laiqin Fm. is brown lava and pyroclastic flow sediment. The Pliocene Wuyu Fm. is grey, brown grey sandstone, siltstone, and mudstone, with coal and oil shale, which is fluvial-lacustrine-swamp facies. The Plio-Pleistocene Dazi Fm. is conglomerate, intercalated with grey mudstone. The Mangxiang Fm., suggesting the significant shifting of sediment provenance, the stable trending of tectonic movement, and the wet and torridity aridity of paleoclimate condition. The Oligo-Miocene paleoclimate and tectonic evolution of the Wuyu Basin has displayed its significance for understanding the early uplift of the Tibetan Plateau.