In order to study the reservoir characteristics and diagenetic evolution sequence of Late Tri-assic in Zhidan-Ganquan area,the microscopic pore structure of the reservoir was examined by combi-ning indirect measurement techniques such as ordinary mercury injection and constant rate mercury in-jection with direct observation techniques such as nuclear magnetic resonance and micron CT,with the core and logging analysis in view.The results show that the Late Triassic reservoir in Zhidan-Ganquan area is dominated by the secondary pores,and the intergranular dissolved pores,intragranular dissolved pores,interstitial dissolved pores and microfractures are developed.Among them,the intragranular dis-solved pores are common,the feldspar dissolved pores are mostly accompanied by intragranular the dis-solved pores,the interstitial dissolved pores are formed by a small amount of laumontite dissolution,and the microfracture dissolved pores are less developed.The minimum values of the reservoir displacement pressure and median pressure in Zhidan-Ganquan area are determined by ordinary mercury injection,and the mercury saturation value and mercury removal efficiency are quantitatively calculated.The throat distribution characteristics of reservoirs with different permeability could be summarized foom,re-sulting in the fact that the throat is the main factor determining the seepage rate.The relaxation time of nuclear magnetic resonance T2 spectrum is positively correlated with the porosity of the reservoir.The pore network model of the reservoir is constructed by micron CT technology,and the pore connectivity of the reservoir is proved to be poor.The research results provide a theoretical basis for the study of res-ervoir characteristics and diagenetic evolution sequence of Yanchang Formation in Zhidan-Ganquan area.
关键词
晚三叠世/孔隙结构特征/成岩演化序列/志丹-甘泉地区
Key words
Late Triassic/pore structure/diagenetic sequence/Zhidan-Ganquan area
维普
万方数据