Abstract:
Abundant storm deposits are developed in the Meso-to Neoproterozoic Gaoyuzhuang and Wumishan Formations in the Yanshan region, northern China, and dominantly made up of sandy-gravelly dolostone and limestone, siliceous tempesitite, micritic dolostone, siliceous banded dolostone and algal stromatolitic dolostone in which five sedimentary structures are observed, including radial structure, sole cast, scour structure, hummocky cross-bedding and wavy bedding. Five representative vertical sedimentary sequences have also been identified for the Wumishan Formation in the Lingyuan region, Liaoning on the basis of lithology and types and scales of the sedimentary structures in integration with regional sedimentary background. These storm deposits were originated from the shallower water intertidal environment in the carbonate platform facies, and thus may be potential hydrocarbon reservoirs because of high structural maturity, developed primary porosity and proximal to the source rocks. The discovery of the storm deposits is believed to be significant to the Meso-to Neoproterozoic palaeogeographic reconstruction and regional stratigraphic correlation in the Yanshan region, northern China.