Study On Geological Conditions Of Natural Gas Accumulation In Yingcheng Formation Of Xingcheng Block,Xushen Gas Field

Xujiaweizi fault depression is the main exploration area of deep gas in Songbei,e specially in Yingcheng Formation,which is located on the source rocks of Shahe forma tion in the middle part of faulted depression.It is the concentrated distribution area of natural gas reservoirs.With the continuous improvement of exploration degree,the explor ation situation of natural gas is becoming more and more serious.The physical distribu tion of deep volcanic rocks and conglomerate reservoirs is complex,and conventional r eservoir prediction technology can not meet the requirements of exploration and develo pment,there is an urgent need for a thorough and thorough study of the differences in the conditions of gas reservoirs and their main controlling factors,which will be of gr eat value to the efficient and rational development of natural gas reservoirs in the late period.This paper takes the Yingcheng Formation of Xingcheng block in Xujiaweizi area as the object of study,on the basis of existing geological,seismic,logging,logging,geoc hemical,sampling and gas test data,itis guided by petroleum geology,geophysics,sedimen tary geology,structural geology and sequence stratigraphy,the inversion processing techni que of multi parameter reservoir constrained by nonlinear space variant wavelet and w ide band wells is taken as the research method,the gas accumulation conditions,gas res ervoir types and distribution patterns,and the main controlling factors of natural gas re servoirs are studied.Comprehensive research results and conclusions are as follows:The thermal evolution history of the Shahe formation in the study area shows tha t most of the Ro in the deep fault depression is more than 2%,which is in the high mature stage,and the organic matter has been transformed into hydrocarbons in large q uantities.The deep source rock samples of the type of organic matter mostly in type II I,the maturity of organic matter in Shahe sub group and Yingcheng Group have reach ed a mature stage,hydrocarbon source rocks have experienced a lot of hydrocarbon ge neration and expulsion period,there are potential source rocks hydrocarbon potential is mainly gas.The gas reservoir types in the study area are structural lithologic gas reservoirs.B ecause of the heterogeneity of reservoirs and poor connectivity in the gas reservoirs,th e four stage conglomerate reservoirs and the weathered crust reservoirs of the first sta ge volcanic rocks are the main gas reservoirs.There is no bottom water in the four member conglomerate gas reservoir,and the marginal water is not obvious.The vertic al distribution of volcanic gas and water layers in the first member of the formation i s gas bearing water,with obvious edge water.The gas distribution and control of multiple factors,the source rock controls the gas distribution and exhaust volume and intensity,angry hydrocarbon source rocks is cl osely related to the hydrocarbon source rock thickness and the faulted reservoir for lar ge gas potential,natural gas reservoir to provide the reservoir space,reservoir types and different the thickness of different gas reservoir in different degree,accumulation layer off cover configuration control of natural gas,natural gas enrichment in the vast majo rity of Gordon two mudstone caprock under Yingcheng three or four reservoir,which i s mainly caused by the lateral distribution of continuous cover.