The wavelet transform (WT) method has been employed to decompose an original geophysical signal into a series of components containing different information about reservoir features such as pore fluids, lithology, a...The wavelet transform (WT) method has been employed to decompose an original geophysical signal into a series of components containing different information about reservoir features such as pore fluids, lithology, and pore structure. We have developed a new method based on WT energy spectra analysis, by which the signal component reflecting the reservoir fluid property is extracted. We have successfully processed real log data from an oil field in central China using this method. The results of the reservoir fluid identification agree with the results of well tests.展开更多
For reservoirs with abnormally high pressure and high geostress,formation resistivity can be greatly affected.This increase of resistivity resulting from high stress causes errors in the identification of reservoir fl...For reservoirs with abnormally high pressure and high geostress,formation resistivity can be greatly affected.This increase of resistivity resulting from high stress causes errors in the identification of reservoir fluids.In order to investigate the effect of stress on resistivity,resistivity measurement was conducted simultaneously with triaxial testing to obtain rock resistivity under high temperature and high pressure.The changes of resistivity and resistivity increasing coefficient with horizontal differential stress and minimum horizontal stress were revealed from experiments.Besides,field data were analyzed to show the main influencing factors of formation resistivity under reservoir conditions.In addition,a new resistivity correction model for high geostress formation was derived in this work.The interpretation results are in good agreement with well testing data in the Keshen area of the Tarim oilfield,China.展开更多
基金This research is sponsored by Nation Natural Science Foundation of China (No.50404001 and No.50374048).
文摘The wavelet transform (WT) method has been employed to decompose an original geophysical signal into a series of components containing different information about reservoir features such as pore fluids, lithology, and pore structure. We have developed a new method based on WT energy spectra analysis, by which the signal component reflecting the reservoir fluid property is extracted. We have successfully processed real log data from an oil field in central China using this method. The results of the reservoir fluid identification agree with the results of well tests.
文摘For reservoirs with abnormally high pressure and high geostress,formation resistivity can be greatly affected.This increase of resistivity resulting from high stress causes errors in the identification of reservoir fluids.In order to investigate the effect of stress on resistivity,resistivity measurement was conducted simultaneously with triaxial testing to obtain rock resistivity under high temperature and high pressure.The changes of resistivity and resistivity increasing coefficient with horizontal differential stress and minimum horizontal stress were revealed from experiments.Besides,field data were analyzed to show the main influencing factors of formation resistivity under reservoir conditions.In addition,a new resistivity correction model for high geostress formation was derived in this work.The interpretation results are in good agreement with well testing data in the Keshen area of the Tarim oilfield,China.