Study On The Sealing Condition Of The Xinglongtai Buried Hill In Liaohe Rift

By the three-dimensional seismic data,drilling data and analysis data,the distribution characteristics and continuity of the caprok is researchued,and the sealing ability is evaluated in this paper study.Based on the structural analysis of the shallow active faults and the statistical analysis of drilling induced fractures,and refer to the results of previous studies on the current territorial stress field,the current direction of the stress field in the research area is determined.Based on the data of hydraulic fracturing,the magnitude of the horizontal principal stress of the measured point is calculated.The rock mechanics parameters were measured by rock mechanics experiment.At last,the present stress field distribution is determined by numerical simulation of stress field.On the basis of the above work,the use of fault vertical sealing evaluation technology and cap rock fracture pressure evaluation technology,critical fracture pressure prediction of cap rock and the fault,and ultimately determine the allowable maximum gas injection capacity.Through the research,the three mechanisms(the expansion and fracture mechanism of the caprok,the expansion mechanism along the preexisting fracture,the active mechanism along the preexisting fracture)of caprok damage are proposed.In the three axial stress state,the corresponding quantitative theoretical model for the failure of the cover layer is established.Application of the theory model,can be in state of stress on the quantitative evaluation of the buried hill first layer stability,to calculate the critical additional fluid pressure(e.g.,the critical gas injection pressure),and applies the molar space under triaxial stress state analysis of the stress?Finally,the gas injection side closure analysis was carried out,and the suggestion of gas injection scheme was put forward.