Response characteristics and application of nuclear magnetic resonance T1-T2 spectrum in shale oil reser-voirs:a case study of Qingshankou Formation in Gulong Sag,Songliao Basin
To clarify the two-dimensional nuclear magnetic resonance(NM R)characteristics of shale oil reservoirs in Gulong Sag,T1-T2 spectra of shales at different states were systematically detected and an-alyzed.The T1-T2 pattern was proposed,and the signal amplitudes of pore water and oil were also cali-brated to calculate the pore fluids at different states in shale pore networks.The main controlling factors of different pore fluid contents in the in-situ state were further explored.The results show that the T1-T2 pattern of the shale oil reservoir in Gulong Sag includes 7 regions,which can effectively distinguish the distribution of various pore fluids.The shale pore fluid mainly consists of capillary-bound water,with an average of 20.95 mg/g in an as-received state.The total oil content is relatively high and has a good correlation with the oil content obtained by conventional pyrolysis,with an average value of 9.67 mg/g.Shale oil is mainly composed of bound oil,followed by adsorbed oil,with less movable oil.Among them,movable oil is the most easily dispersed,followed by bound oil,with less loss of adsorbed oil and capillary-bound water.In-situ shale oil content is mainly controlled by organic carbon,clay min-erals,and maturity.The higher the content of organic carbon and clay minerals,the greater the maturi-ty and the higher the oil content.While the adsorbed oil is decreasing with increasing maturity.
shale oilpore fluidsnuclear magnetic resonanceT1-T2 spectrumQingshankou Forma-tionGulong SagSongliao Basin
国家科技期刊平台
NSTL
万方数据
