Research On Sedimentary Microfacies And Lithologic Reservoir Of Qing3 In Qianxibei Area

Taking high-resolution sequence stratigraphy theories as guidance, this study comprehensively used full and accurate well core, well logging, mud logging, oil testing and the 3-D seismic data, etc. Through the analysis of different grades base level cycle and identification of interface, high-resolution sequence stratigraphic framework in the 3rd member of Qingshankou formation in the Qianxibei area of the southern Songliao Basin is established. Research shows that, the very complicated distribution of oil and water in this area is not controlled by formation, sand, or even a small group, but by the single sand, and the single sand is the key to restrict and understand the formation of qn3. Qn3 delta front sandbody of Qianxibei area is banded single sand body group to the North East. At the end of the Ming Dynasty the local structure reversed to form updip pinchout and pinchout to the sides with large lithologictrap group and reservoir of favorable conditions. Finding of far sand bar in the most main 25 layer and prediction of large band far sand bar of up to 20 km and width 1000 to 2000 m are significant for the exploration and development. At the same time point out that the south of the study area of the low level of exploration is the potential area.Target layer should be lower layers of qn3(XI, XII sand group) instead of the upper part of qn3(VII, VIII, IX, II) formation in the east of main exploration area.