关键词: 塔里木盆地, 泥盆系, 石炭系, 东河砂岩, 沉积期次, 沉积环境

Abstract:

Donghe sandstone is the diachronous stratigraphical unit from the Late Devonian to the Early Carboniferous and controls the distribution of hydrocarbon reservoirs in Tarim Basin. The evolvement of sedimentary conditions and distribution rules of Donghe sandstone were analyzed by applying the sequence stratigraphic theory, according to the data of outcrops, drilling and seism. The sedimentary pattern was resulted from overlapping of Tazhong Uplift and Tabei Uplift under the condition of transgression. The sedimentation of Donghe sandstone can be divided into five periods. The sediment of sandstone in the first period distributes in Maigaiti Slope and Bachu Uplift. The sediment of sandstone in the second period is mainly in the low heave of Bachu Uplift and Tazhong Uplift. The sediment of sandstone in the third period is mostly in the Tazhong Uplift and Tabei Uplift. The forth sediment of sandstone is in Tabei Uplift, and the fifth one distributes mainly in Tabei Uplift and around the periphery of Tadong Low Uplift. The Donghe sandstone bodies have various lithofacies such as glutenite, gritstone, medium-sandstone and fine-sandstone. The sedimentary environment mainly include shore and river estuary. The sandstone bodies in the different period differ from each other in sedimentary characteristics of reservoir-seal combination and pool-forming conditions. The different patterns of hydrocarbon exploration should be taken in the different sediment period of sandstone bodies and different areas.

Key words: Tarim Basin, Devonian System, Carboniferous System, Donghe sandstone, sedimentary period, sedimentary environment