Study On The Sedimentary Characteristics Of Tong Bomiao Group In Southern Area Of Wuerxun Hollow

Based on the theories of sequence stratigraphy, petroleum geology, sedimentary petrography, structural geology, combined with the data on core, seismic, imaging logging, well logging, etc. Analyse and study of the sequence formation and sedimentary facies of TongBomiao group in southern area of WuErxun hollow. At the same time, in this paper linking previous studies and the initial work above, carried on the forecast about the advantageous area.The results have actual guiding significances on the future hydrocarbon exploration and development as well as the allocation of the well location in the area.In WerErxun depression, T₃ which is the interface between TongBomiao and NanTun group is a larger regional unconformity. TaMulangou group in wunan is missing entirety. T₄ was on the superd by T₅, that is the end of the TongBomiao group is T₅. T₅ is a regional angular unconformities. Based on interpretation of seismic data, single well layer division, we successed on the unification of the drilling stratification and the seismic interface, and established the sequence stratigraphic framework. we divided the TongBomiao formation into four fouth-order sequences from bottom to top, as TSQ₁,TSQ₂,TSQ₃ and TSQ₄. All system tracts are fully developed in each four-order sequence. We studied the deposition system of each sequence basised on the division in the four sequences.A research method synthesizing core observation, the data of the logging and well logging and seismic data was adopted to define fan-delta facies, lacustrine facies, volcanic rock facies. The mainly facies type in this horizon is fan-delta facies, the second is shore shallow lacustrine, and volcanic rock facies is uncommon. The sequence of TSQ₁ developes shore shallow lacustrine, however, TSQ₂, TSQ₃ and TSQ₄ mainly develop fan-delta facies. We made clear the type of sedimentary facies and sedimentary filling evolution, characteristic of the depositional system, etc.Finally, based on the work accomplished by this project and results of previous studies, we pointed out the favorable exploration regions in the research. In the end of this thesis, it is revealed Fan deltas front is superior quality reservoir, and then shore-shallow lacustrine.