This study focuses on using spectral decomposition(SD)technique to characterize complicated reservoirs to understand the structural and stratigraphic variations in the interpreted horizons from Bisol field.The purpose...This study focuses on using spectral decomposition(SD)technique to characterize complicated reservoirs to understand the structural and stratigraphic variations in the interpreted horizons from Bisol field.The purpose of this study is to use geophysical and well logging data sets to map the thin-bedded sandstone reservoirs and prospect zones within the multiple reservoirs in Bisol field,Niger Delta.The interpretation of faults and horizons was carried out on the seismic section,which was further used to produce the structural maps.Seismic attributes such as trace and variance were used to enhance the truncated structures from the seismic section,while the produced spectra were used to delineate the stratigraphy and thickness of the thin-bedded reservoirs.Thin sandstone reservoirs were identified from well logs and consequently mapped on the seismic section.Fast Fourier Transform workflow was successfully used to image the stratigraphic features in the study area.Three horizons(S1T,S2T and S3T)were delineated from the seismic section,and four reservoirs were mapped and correlated across the wells.Frequency analyses from the seismic sectional view revealed some thin pay sandstone reservoirs,which were characterized by high amplitude.Three new probable zones(Prospect A,B and C)of hydrocarbon accumulation were identified using the SD technique.展开更多
Spectrum analysis of natural gamma ray spectral logging （SGR） data is a critical part of surface informa- tion processing systems. Due to the low resolution, which is an inherent weakness of SGR, and the low signal-...Spectrum analysis of natural gamma ray spectral logging （SGR） data is a critical part of surface informa- tion processing systems. Due to the low resolution, which is an inherent weakness of SGR, and the low signal-to-noise ratio problem of logging measurements, SGR is usually treated with a low confidence level. The Direct Demodulation （DD） method is an advanced technique to solve modulation equations interactively under physical constraints. It has higher sensitivity and spatial resolution than the traditional methods and can effectively suppress the logging noise. Based on standard count rate spectral data obtained from the China Offshore Oil Logging Company SGR Calibration Facility, this paper presents the application of the DD method to gamma-ray logging. The results are compared with four traditional algorithmic methods, showing that the DD method is a credible choice, with higher sensitivity and higher spatial resolution in gamma-ray log interpretation. The Point-Spread-Function of the Shengli Oil Logging Company＇s natural gamma ray spectroscopy instrument is obtained for the first time. The quantities of various radionuclides in their calibration pits are also obtained. The DD method was applied successfully to gamma-ray logging, offering a new option for SGR logging algorithm selection.展开更多
In this article, numerical modeling of borehole radar for well logging in time domain is developed using pseudo-spectral time domain algorithm in axisymmetric cylindrical coordinate for proximate true formation model....In this article, numerical modeling of borehole radar for well logging in time domain is developed using pseudo-spectral time domain algorithm in axisymmetric cylindrical coordinate for proximate true formation model. The conductivity and relative permittivity logging curves are obtained from the data of borehole radar for well logging. Since the relative permittivity logging curve is not affected by salinity of formation water, borehole radar for well logging has obvious advantages as compared with conventional electrical logging. The borehole radar for well logging is a one-transmitter and two-receiver logging tool. The conductivity and relative permittivity logging curves are obtained successfully by measuring the amplitude radio and the time difference of pulse waveform from two receivers. The calculated conductivity and relative permittivity logging curves are close to the true value of surrounding formation, which tests the usability and reliability of borehole radar for well logging. The numerical modeling of borehole radar for well logging laid the important foundation for researching its logging tool.展开更多
文摘This study focuses on using spectral decomposition(SD)technique to characterize complicated reservoirs to understand the structural and stratigraphic variations in the interpreted horizons from Bisol field.The purpose of this study is to use geophysical and well logging data sets to map the thin-bedded sandstone reservoirs and prospect zones within the multiple reservoirs in Bisol field,Niger Delta.The interpretation of faults and horizons was carried out on the seismic section,which was further used to produce the structural maps.Seismic attributes such as trace and variance were used to enhance the truncated structures from the seismic section,while the produced spectra were used to delineate the stratigraphy and thickness of the thin-bedded reservoirs.Thin sandstone reservoirs were identified from well logs and consequently mapped on the seismic section.Fast Fourier Transform workflow was successfully used to image the stratigraphic features in the study area.Three horizons(S1T,S2T and S3T)were delineated from the seismic section,and four reservoirs were mapped and correlated across the wells.Frequency analyses from the seismic sectional view revealed some thin pay sandstone reservoirs,which were characterized by high amplitude.Three new probable zones(Prospect A,B and C)of hydrocarbon accumulation were identified using the SD technique.
基金Supported by National High Technology Research and Development Program of China(2013AA064702)National Major Special Well logging Company of Shengli Petroleum Administration Bureau of Sinopec Group(2011ZX05006-002)
文摘Spectrum analysis of natural gamma ray spectral logging （SGR） data is a critical part of surface informa- tion processing systems. Due to the low resolution, which is an inherent weakness of SGR, and the low signal-to-noise ratio problem of logging measurements, SGR is usually treated with a low confidence level. The Direct Demodulation （DD） method is an advanced technique to solve modulation equations interactively under physical constraints. It has higher sensitivity and spatial resolution than the traditional methods and can effectively suppress the logging noise. Based on standard count rate spectral data obtained from the China Offshore Oil Logging Company SGR Calibration Facility, this paper presents the application of the DD method to gamma-ray logging. The results are compared with four traditional algorithmic methods, showing that the DD method is a credible choice, with higher sensitivity and higher spatial resolution in gamma-ray log interpretation. The Point-Spread-Function of the Shengli Oil Logging Company＇s natural gamma ray spectroscopy instrument is obtained for the first time. The quantities of various radionuclides in their calibration pits are also obtained. The DD method was applied successfully to gamma-ray logging, offering a new option for SGR logging algorithm selection.
基金supported by the Open Fund of Key Laboratory of Geo-detection (China University of Geosciences,Beijing),Ministry of Education (No. GDL0805)
文摘In this article, numerical modeling of borehole radar for well logging in time domain is developed using pseudo-spectral time domain algorithm in axisymmetric cylindrical coordinate for proximate true formation model. The conductivity and relative permittivity logging curves are obtained from the data of borehole radar for well logging. Since the relative permittivity logging curve is not affected by salinity of formation water, borehole radar for well logging has obvious advantages as compared with conventional electrical logging. The borehole radar for well logging is a one-transmitter and two-receiver logging tool. The conductivity and relative permittivity logging curves are obtained successfully by measuring the amplitude radio and the time difference of pulse waveform from two receivers. The calculated conductivity and relative permittivity logging curves are close to the true value of surrounding formation, which tests the usability and reliability of borehole radar for well logging. The numerical modeling of borehole radar for well logging laid the important foundation for researching its logging tool.
