The major storage space types in the carbonate reservoir in the Ordovician in the TZ45 area are secondary dissolution caves.For the prediction of caved carbonate reservoir,post-stack methods are commonly used in the o...The major storage space types in the carbonate reservoir in the Ordovician in the TZ45 area are secondary dissolution caves.For the prediction of caved carbonate reservoir,post-stack methods are commonly used in the oilfield at present since pre-stack inversion is always limited by poor seismic data quality and insufficient logging data.In this paper,based on amplitude preserved seismic data processing and rock-physics analysis,pre-stack inversion is employed to predict the caved carbonate reservoir in TZ45 area by seriously controlling the quality of inversion procedures.These procedures mainly include angle-gather conversion,partial stack,wavelet estimation,low-frequency model building and inversion residual analysis.The amplitude-preserved data processing method can achieve high quality data based on the principle that they are very consistent with the synthetics.Besides,the foundation of pre-stack inversion and reservoir prediction criterion can be established by the connection between reservoir property and seismic reflection through rock-physics analysis.Finally,the inversion result is consistent with drilling wells in most cases.It is concluded that integrated with amplitude-preserved processing and rock-physics,pre-stack inversion can be effectively applied in the caved carbonate reservoir prediction.展开更多
Conventional seismic exploration method based on post-stack data usually fails to identify the distribution of fractured and caved carbonate reservoirs in the Tarim Basin,so the rich pre-stack information should be ap...Conventional seismic exploration method based on post-stack data usually fails to identify the distribution of fractured and caved carbonate reservoirs in the Tarim Basin,so the rich pre-stack information should be applied to the prediction of carbonate reservoirs.Amplitude-preserved seismic data processing is the foundation.In this paper,according to the feature of desert seismic data (including weak reflection,fast attenuation of high frequency components,strong coherent noises,low S/N and resolution),a set of amplitude-preserved processing techniques is applied and a reasonable processing flow is formed to obtain the high quality data.After implementing a set of pre-stack amplitude-preserved processing,we test and define the kernel parameters of amplitude-preserved Kirchhoff PSTM (pre-stack time migration) and subsequent gathers processing,in order to obtain the amplitude-preserved gathers used to the isotropic pre-stack inversion for the identification of caved reservoirs.The AVO characteristics of obtained gathers fit well with the synthetic gathers from logging data,and it proves that the processing above is amplitudepreserved.The azimuthal processing techniques,including azimuth division and binning enlargement,are implemented for amplitude-preserved azimuthal gathers with the uniform fold.They can be used in the anisotropic inversion to detect effective fractures.The processing techniques and flows are applied to the field seismic data,and are proved available for providing the amplitude-preserved gathers for carbonate reservoir prediction in the Tarim Basin.展开更多
The Silurian hydrocarbon exploration in the northwest Tarim Basin had long been fruitless, till Well XSD1 drilled in 2018 in the Shajingzi structural belt, northwest Tarim Basin tapped industrial gas flow from the Sil...The Silurian hydrocarbon exploration in the northwest Tarim Basin had long been fruitless, till Well XSD1 drilled in 2018 in the Shajingzi structural belt, northwest Tarim Basin tapped industrial gas flow from the Silurian for the first time. The reservoir-forming model and resource extent need to be made clear urgently. Based on the comprehensive research of drilling,formation testing, geochemical data, and sedimentary and accumulation history, in combination with field surveys, experiments, structure interpretation and reconstruction of structure evolution, it is found that:(1) The northwest Tarim Basin had widespread tidal deltaic deposits in the Silurian period, which contain good reservoir-cap combinations;(2) the Shajingzi fault and associated faults connected the Cambrian-Ordovician source rocks in the Awati sag, and controlled the formation of Silurian structural traps, hence, the traps turned up along the structural belt in an orderly pattern and came together into contiguous tracts;(3) the Silurian petroleum in Shajingzi structural belt was dominated by gas, and the major accumulation period was the Himalayan period when the traps fixed in shape;(4) the Silurian gas resources in the Shajingzi belt were estimated at around 2.018×10^(11)m^(3), and Silurian gas resources of the northwest Tarim Basin were estimated at 2.03×10^(12)m^(3), implying huge exploration potential, so this area will become a major area for reserve and production increase from clastic strata in the basin;(5) with the Shajingzi fault of large scale and long active time connecting deep source rock layers, multiple formations in Lower Paleozoic of Shajingzi structural belt may have breakthroughs in hydrocarbon exploration.展开更多
Both the XWD1 and XWD2 wells drilled in 2017 in the Wensu salient, northwest Tarim Basin have achieved high-yield industrial oil flow. Based on the comprehensive research on drilling, oil testing, geochemistry and log...Both the XWD1 and XWD2 wells drilled in 2017 in the Wensu salient, northwest Tarim Basin have achieved high-yield industrial oil flow. Based on the comprehensive research on drilling, oil testing, geochemistry and logging data, in combination with the field surveys, 2 D seismic data processing and interpretation as well as sedimentation and accumulation history comparison, we carefully compared the source conditions, migration channels, reservoir-cap distribution and trapping types in the Wensu salient, and subsequently constructed a reservoir-forming pattern. Though the Wensu salient is lack of source rocks, some drainage systems were widely developed and efficiently connected to adjacent fertile depressions. Due to the moderate Miocene paleogeomorphic conditions in the Wensu salient, the delta and shore-shallow lacustrine beach bar sandy bodies were developed within the Jidike formation, and consequently form widely distributed structural-lithologic traps. The hydrocarbon generation, migration and accumulation mainly happened in the Neogene-Quaternary period, which suggests that the reservoir-forming pattern should be characterized as late-period and compound accumulation. It suggests that, although the border belts in the Tarim Basin might be short of source rocks and structural traps, they are potential to accumulate hydrocarbon in a large scale; the description of efficient hydrocarbon migration channels and structural-lithologic traps is crucial for any successful exploration.展开更多
基金supported by National Basic Research Program(2006CB202304)of Chinaco-supported by the National Basic Research Program of China(Grant No.2011CB201103)the National Science and Technology Major Project of China(Grant No.2011ZX05004003)
文摘The major storage space types in the carbonate reservoir in the Ordovician in the TZ45 area are secondary dissolution caves.For the prediction of caved carbonate reservoir,post-stack methods are commonly used in the oilfield at present since pre-stack inversion is always limited by poor seismic data quality and insufficient logging data.In this paper,based on amplitude preserved seismic data processing and rock-physics analysis,pre-stack inversion is employed to predict the caved carbonate reservoir in TZ45 area by seriously controlling the quality of inversion procedures.These procedures mainly include angle-gather conversion,partial stack,wavelet estimation,low-frequency model building and inversion residual analysis.The amplitude-preserved data processing method can achieve high quality data based on the principle that they are very consistent with the synthetics.Besides,the foundation of pre-stack inversion and reservoir prediction criterion can be established by the connection between reservoir property and seismic reflection through rock-physics analysis.Finally,the inversion result is consistent with drilling wells in most cases.It is concluded that integrated with amplitude-preserved processing and rock-physics,pre-stack inversion can be effectively applied in the caved carbonate reservoir prediction.
基金financially supported by National Basic Research Program of China(No.2011CB201100)
文摘Conventional seismic exploration method based on post-stack data usually fails to identify the distribution of fractured and caved carbonate reservoirs in the Tarim Basin,so the rich pre-stack information should be applied to the prediction of carbonate reservoirs.Amplitude-preserved seismic data processing is the foundation.In this paper,according to the feature of desert seismic data (including weak reflection,fast attenuation of high frequency components,strong coherent noises,low S/N and resolution),a set of amplitude-preserved processing techniques is applied and a reasonable processing flow is formed to obtain the high quality data.After implementing a set of pre-stack amplitude-preserved processing,we test and define the kernel parameters of amplitude-preserved Kirchhoff PSTM (pre-stack time migration) and subsequent gathers processing,in order to obtain the amplitude-preserved gathers used to the isotropic pre-stack inversion for the identification of caved reservoirs.The AVO characteristics of obtained gathers fit well with the synthetic gathers from logging data,and it proves that the processing above is amplitudepreserved.The azimuthal processing techniques,including azimuth division and binning enlargement,are implemented for amplitude-preserved azimuthal gathers with the uniform fold.They can be used in the anisotropic inversion to detect effective fractures.The processing techniques and flows are applied to the field seismic data,and are proved available for providing the amplitude-preserved gathers for carbonate reservoir prediction in the Tarim Basin.
基金Supported by the China Geological Survey Project (DD20190106,DD20190090)。
文摘The Silurian hydrocarbon exploration in the northwest Tarim Basin had long been fruitless, till Well XSD1 drilled in 2018 in the Shajingzi structural belt, northwest Tarim Basin tapped industrial gas flow from the Silurian for the first time. The reservoir-forming model and resource extent need to be made clear urgently. Based on the comprehensive research of drilling,formation testing, geochemical data, and sedimentary and accumulation history, in combination with field surveys, experiments, structure interpretation and reconstruction of structure evolution, it is found that:(1) The northwest Tarim Basin had widespread tidal deltaic deposits in the Silurian period, which contain good reservoir-cap combinations;(2) the Shajingzi fault and associated faults connected the Cambrian-Ordovician source rocks in the Awati sag, and controlled the formation of Silurian structural traps, hence, the traps turned up along the structural belt in an orderly pattern and came together into contiguous tracts;(3) the Silurian petroleum in Shajingzi structural belt was dominated by gas, and the major accumulation period was the Himalayan period when the traps fixed in shape;(4) the Silurian gas resources in the Shajingzi belt were estimated at around 2.018×10^(11)m^(3), and Silurian gas resources of the northwest Tarim Basin were estimated at 2.03×10^(12)m^(3), implying huge exploration potential, so this area will become a major area for reserve and production increase from clastic strata in the basin;(5) with the Shajingzi fault of large scale and long active time connecting deep source rock layers, multiple formations in Lower Paleozoic of Shajingzi structural belt may have breakthroughs in hydrocarbon exploration.
基金Supported by China Geological Survey Projects(DD20160203,DD20189602,DD20160169)
文摘Both the XWD1 and XWD2 wells drilled in 2017 in the Wensu salient, northwest Tarim Basin have achieved high-yield industrial oil flow. Based on the comprehensive research on drilling, oil testing, geochemistry and logging data, in combination with the field surveys, 2 D seismic data processing and interpretation as well as sedimentation and accumulation history comparison, we carefully compared the source conditions, migration channels, reservoir-cap distribution and trapping types in the Wensu salient, and subsequently constructed a reservoir-forming pattern. Though the Wensu salient is lack of source rocks, some drainage systems were widely developed and efficiently connected to adjacent fertile depressions. Due to the moderate Miocene paleogeomorphic conditions in the Wensu salient, the delta and shore-shallow lacustrine beach bar sandy bodies were developed within the Jidike formation, and consequently form widely distributed structural-lithologic traps. The hydrocarbon generation, migration and accumulation mainly happened in the Neogene-Quaternary period, which suggests that the reservoir-forming pattern should be characterized as late-period and compound accumulation. It suggests that, although the border belts in the Tarim Basin might be short of source rocks and structural traps, they are potential to accumulate hydrocarbon in a large scale; the description of efficient hydrocarbon migration channels and structural-lithologic traps is crucial for any successful exploration.
