Research On Sequence Characteristics Of Nantun Group In Northern Area Of Wuerxun Hollow

The essay based on the recent theory and method of Sequence Stratigraphy, Seismic Stratigraphy and Sedimentology, according to observe large numbers of cores, uses seismic, logging and core information to analyze and research the sequence characteristics, formation framework and sedimentary facie in NanTun Group in Northern Area of WuErxun Hollow. Moreover, combined with structural geology feature of Wubei in WuErxun Hollow, we searched on the characteristics of the sequence and prediceted the distributiong area of favorable facie body. This study can offer the dependable evidence for sequence division, and offer the support for the future exploration and development of oil and gas.According to seismic, comprehensive logging, logging and core information, this paper classifies Nantun group into two three-order sequences,seven fouth-order sequences. All system tracts are fully developed in each third-order sequence.The interface of the two third-order sequence is located at the conversion surface of the lithology and electric nature. The interface presents the character of partly truncation below,and it presents the character of onlap above.During the depositional period of Nantun group,this area developing many types of precipitation facies, such as braided fluvial delta facies, Fan-delta facies, lacustrine facies. Evaluating the reservoir comprehensively according to the result of sedimentary facies, the comprehensive analysis of reservoir lithology parameter.This paper predicts favorable perspective plays by comprehensively considering basic conditions for the formation of reservoir, for example, source bed, reservoir, cap rock and the combination of these.