Formation and evolution of the Nanshanping anticline in the central Yangtze plate

Abstract：The Nanshanping anticline, located in the center of the Yangtze plate, is a destroyed ancient oil accumulation. The upper Sinian in the core of the anticline contains large amount of bitumen. Based on an analysis of the sequence of strata, the authors propose that the Sinian to Middle Triassic was a period of paleo-uplift development, which may be further divided into the Sinian embryonic paleo-uplift stage, Early Paleozoic paleo-uplift conservation stage and Late Paleozoic to Middle Triassic paleo-uplift development stage. Analysis of modification suggests that the period from the Late Triassic to Cenezoic was a period of the development of faults and folds, which may be subdivided into the stage of Late Triassic-Middle Jurassic broad anticline development, stage of fault propagation and anticline development in the II phase of the Yanshanian movement and stage of late Yanshanian and Himalayan anticline modification. The Nanshanping ancient oil accumulation takes dolomitite of the upper Sinian Dengying Formation as the reservoir and black carbonaceous mudstone and stone coals of the overlying Lower Cambrian Niutitang Formation as source rocks. Oil and gas were accumulated in the paleo-uplift from Silurian to Middle Triassic. The Late Triassic and Middle Jurassic witnessed the redistribution and formation of the Nanshanping ancient oil accumulation. Later the ancient oil accumulation was destroyed.