SEDIMENTARY FEATURE AND OPTIMIZATION OF EXPLORATION PROSPECTS OF SHAN 2 NUMBER IN THE MIDDLE-EAST OF ORDOS BASIN
鄂尔多斯盆地中东部地区山2段储层沉积特征及勘探目标评选

Through analyzing shan 2 number sandbody in the middle-east of Ordos basin, it is thought that the east-west zoning of shan 2 number sandbody is controlled by original differentiation and hydrodynamic force strength. The quartz sandstone formed by the strong hydrodynamic force has the characteristics of one-high and three-low that is high quartz, low martix, low-soft lithic-fragment and few feldspar in the wastern sand belt, Yulin. But the litharenite formed by the weak hydrodynamic force is different from the quartz sandstone in the eastern sand belt,Shenmu. It has the three-high property of high martix, high-soft lithic-fragment and high feldspar. At the same time the evolution from late Paleozoic is looked upon as main line. It is studied by the applied of the sequence stratigraphy that the distribution of depositional system and feature of basin filling in the isochron stratigraphic framework. It is thought that shan 2 period is a suit of river-delta-lake depositional system. Its sedimentary evolution is represented as the long expanding process of lake and northward recession of alluvial system. Three suits of superposition sandbody that are the retrogressive deposit northward are formed by three periods of lake process in this age. The delta front facies tract is the favorable exploration prospect area in all suits of sandbody.