The Qiongdongnan Basin has the first proprietary high-yield gas field in deep-water areas of China and makes the significant breakthroughs in oil and gas exploration.The central depression belt of deep-water area in t...The Qiongdongnan Basin has the first proprietary high-yield gas field in deep-water areas of China and makes the significant breakthroughs in oil and gas exploration.The central depression belt of deep-water area in the Qiongdongnan Basin is constituted by five sags,i.e.Ledong Sag,Lingshui Sag,Songnan Sag,Baodao Sag and Changchang Sag.It is a Cenozoic extensional basin with the basement of pre-Paleogene as a whole.The structural research in central depression belt of deep-water area in the Qiongdongnan Basin has the important meaning in solving the basic geological problems,and improving the exploration of oil and gas of this basin.The seismic interpretation and structural analysis in this article was operated with the 3D seismic of about 1.5×104 km2 and the 2D seismic of about 1×104 km.Eighteen sampling points were selected to calculate the fault activity rates of the No.2 Fault.The deposition rate was calculated by the ratio of residual formation thickness to deposition time scale.The paleo-geomorphic restoration was obtained by residual thickness method and impression method.The faults in the central depression belt of deep-water area of this basin were mainly developed during Paleogene,and chiefly trend in NE–SW,E–W and NW–SE directions.The architectures of these sags change regularly from east to west:the asymmetric grabens are developed in the Ledong Sag,western Lingshui Sag,eastern Baodao Sag,and western Changchang Sag;half-grabens are developed in the Songnan Sag,eastern Lingshui Sag,and eastern Changchang Sag.The tectonic evolution history in deep-water area of this basin can be divided into three stages,i.e.faulted-depression stage,thermal subsidence stage,and neotectonic stage.The Ledong-Lingshui sags,near the Red River Fault,developed large-scale sedimentary and subsidence by the uplift of Qinghai-Tibet Plateau during neotectonic stage.The Baodao-Changchang sags,near the northwest oceanic sub-basin,developed the large-scale magmatic activities and the transition of stress direction by the expansion of the South China Sea.The east sag belt and west sag belt of the deep-water area in the Qiongdongnan Basin,separated by the ancient Songnan bulge,present prominent differences in deposition filling,diaper genesis,and sag connectivity.The west sag belt has the advantages in high maturity,well-developed fluid diapirs and channel sand bodies,thus it has superior conditions for oil and gas migration and accumulation.The east sag belt is qualified by the abundant resources of oil and gas.The Paleogene of Songnan low bulge,located between the west sag belt and the east sag belt,is the exploration potential.The YL 8 area,located in the southwestern high part of the Songnan low bulge,is a favorable target for the future gas exploration.The Well 8-1-1 was drilled in August 2018 and obtained potential business discovery,and the Well YL8-3-1 was drilled in July 2019 and obtained the business discovery.展开更多
"Bicycle Zodiac Decoration Competition"is a Mexican local brand under the framework of the global brand"Happy Chinese New Year",It was first established in Mexico City in 2017 and has been successf..."Bicycle Zodiac Decoration Competition"is a Mexican local brand under the framework of the global brand"Happy Chinese New Year",It was first established in Mexico City in 2017 and has been successfully held in Mexico City for 6 times.展开更多
Oligocene(fan)delta-associated coal measures and marine source rocks are the main gas-generating source rocks in the Qiongdongnan Basin,and(fan)delta sand bodies are the dominant types of reservoirs.By comprehensively...Oligocene(fan)delta-associated coal measures and marine source rocks are the main gas-generating source rocks in the Qiongdongnan Basin,and(fan)delta sand bodies are the dominant types of reservoirs.By comprehensively utilizing a large amount of 2D and 3D seismic data and new drilling data,the distribution of(fan)deltas and three types of Oligocene fault fan systems were systematically identified;these are thought to have had joint control over the development of hydrocarbon source rocks and reservoirs.The three types of Oligocene fault fan coupling relationships in the Qiongdongnan Basin were found to be fault bend,fault gully,and fault tip.The fault bend type of(fan)delta developed at the bend of the fault and was distributed in the downthrown block of Fault Nos.5 and 2.The fault tip type developed where the fault died out toward the source direction and was distributed near the eastewest faults on the north and south sides of Baodao and Changchang Sags.The fault gully type developed along the fault trend in the downthrown block and was mainly distributed in areas including the northern part of Ya'nan Sag and the Fault No.3 downthrown block.The fault bend(fan)delta is surrounded by a relatively closed bay environment,and the terrigenously dominated marine source rocks in the still water bay environment were developed with a high hydrocarbon generation index and high hydrocarbon generation potential.Fault tip and fault gully types of(fan)delta plain facies have a wide distribution of plain subfacies,which is conducive to the development of coal-measure source rocks that have excellent gas potential.During sedimentation of the fault gully and the fault tip delta,the terrain was relatively flat,with sand bodies strongly reworked by hydrodynamic force;the reservoir quality of the sand bodies in the underwater distributary channel and estuary dam are good,and the sand bodies have wide distribution.The sand bodies of the fault bend type of(fan)delta were deposited rapidly near the source kitchen,and the degree of sorting and rounding was poor,which resulted in the poor physical properties of the plain subfacies.In the southern and northern step-fault zones of Baodao Sag in the eastern part of this basin,the fault bend,fault tip,and fault trench(fan)deltas were inherited and further developed,and the source-reservoir configuration conditions were favorable.Exploration deployment was carried out in the Baodao 21 area in the northern step-fault zone and the Yongle 10 area in the southern step-fault zone,where new discoveries in natural gas exploration have been realized.In the eastern part of this basin,the fault bend,fault tip,and fault gully(fan)deltas in the southern and northern fault step zones of Baodao Sag were successively developed,which were beneficial for favorable sourceereservoir configuration conditions.The natural gas exploration successes in the Baodao-21 area in the northern fault step zone and the Yongle-10 area in the southern fault step zone are beneficial for new discoveries in natural gas exploration in the Qiongdongnan Basin.展开更多
基金The National Natural Science Foundation of China under contract No.91528303the National Science and Technology Major Project under contract Nos 2016ZX05026,2011ZX05025 and 2008ZX05025the National Basic Research Program(973 Program)of China under contract No.2009CB219400
文摘The Qiongdongnan Basin has the first proprietary high-yield gas field in deep-water areas of China and makes the significant breakthroughs in oil and gas exploration.The central depression belt of deep-water area in the Qiongdongnan Basin is constituted by five sags,i.e.Ledong Sag,Lingshui Sag,Songnan Sag,Baodao Sag and Changchang Sag.It is a Cenozoic extensional basin with the basement of pre-Paleogene as a whole.The structural research in central depression belt of deep-water area in the Qiongdongnan Basin has the important meaning in solving the basic geological problems,and improving the exploration of oil and gas of this basin.The seismic interpretation and structural analysis in this article was operated with the 3D seismic of about 1.5×104 km2 and the 2D seismic of about 1×104 km.Eighteen sampling points were selected to calculate the fault activity rates of the No.2 Fault.The deposition rate was calculated by the ratio of residual formation thickness to deposition time scale.The paleo-geomorphic restoration was obtained by residual thickness method and impression method.The faults in the central depression belt of deep-water area of this basin were mainly developed during Paleogene,and chiefly trend in NE–SW,E–W and NW–SE directions.The architectures of these sags change regularly from east to west:the asymmetric grabens are developed in the Ledong Sag,western Lingshui Sag,eastern Baodao Sag,and western Changchang Sag;half-grabens are developed in the Songnan Sag,eastern Lingshui Sag,and eastern Changchang Sag.The tectonic evolution history in deep-water area of this basin can be divided into three stages,i.e.faulted-depression stage,thermal subsidence stage,and neotectonic stage.The Ledong-Lingshui sags,near the Red River Fault,developed large-scale sedimentary and subsidence by the uplift of Qinghai-Tibet Plateau during neotectonic stage.The Baodao-Changchang sags,near the northwest oceanic sub-basin,developed the large-scale magmatic activities and the transition of stress direction by the expansion of the South China Sea.The east sag belt and west sag belt of the deep-water area in the Qiongdongnan Basin,separated by the ancient Songnan bulge,present prominent differences in deposition filling,diaper genesis,and sag connectivity.The west sag belt has the advantages in high maturity,well-developed fluid diapirs and channel sand bodies,thus it has superior conditions for oil and gas migration and accumulation.The east sag belt is qualified by the abundant resources of oil and gas.The Paleogene of Songnan low bulge,located between the west sag belt and the east sag belt,is the exploration potential.The YL 8 area,located in the southwestern high part of the Songnan low bulge,is a favorable target for the future gas exploration.The Well 8-1-1 was drilled in August 2018 and obtained potential business discovery,and the Well YL8-3-1 was drilled in July 2019 and obtained the business discovery.
文摘"Bicycle Zodiac Decoration Competition"is a Mexican local brand under the framework of the global brand"Happy Chinese New Year",It was first established in Mexico City in 2017 and has been successfully held in Mexico City for 6 times.
基金funded by the National Natural Science Foundation of China under contract number 91528303the National Science and Technology Major Project under contract numbers 2016ZX05026,2011ZX05025,and 2008ZX05025+1 种基金the National Basic Research Program(973 Program)of China under contract number 2009CB219400the Science and Technology Project of China National Offshore Oil Corporation under contract number KJGG2022-0101.
文摘Oligocene(fan)delta-associated coal measures and marine source rocks are the main gas-generating source rocks in the Qiongdongnan Basin,and(fan)delta sand bodies are the dominant types of reservoirs.By comprehensively utilizing a large amount of 2D and 3D seismic data and new drilling data,the distribution of(fan)deltas and three types of Oligocene fault fan systems were systematically identified;these are thought to have had joint control over the development of hydrocarbon source rocks and reservoirs.The three types of Oligocene fault fan coupling relationships in the Qiongdongnan Basin were found to be fault bend,fault gully,and fault tip.The fault bend type of(fan)delta developed at the bend of the fault and was distributed in the downthrown block of Fault Nos.5 and 2.The fault tip type developed where the fault died out toward the source direction and was distributed near the eastewest faults on the north and south sides of Baodao and Changchang Sags.The fault gully type developed along the fault trend in the downthrown block and was mainly distributed in areas including the northern part of Ya'nan Sag and the Fault No.3 downthrown block.The fault bend(fan)delta is surrounded by a relatively closed bay environment,and the terrigenously dominated marine source rocks in the still water bay environment were developed with a high hydrocarbon generation index and high hydrocarbon generation potential.Fault tip and fault gully types of(fan)delta plain facies have a wide distribution of plain subfacies,which is conducive to the development of coal-measure source rocks that have excellent gas potential.During sedimentation of the fault gully and the fault tip delta,the terrain was relatively flat,with sand bodies strongly reworked by hydrodynamic force;the reservoir quality of the sand bodies in the underwater distributary channel and estuary dam are good,and the sand bodies have wide distribution.The sand bodies of the fault bend type of(fan)delta were deposited rapidly near the source kitchen,and the degree of sorting and rounding was poor,which resulted in the poor physical properties of the plain subfacies.In the southern and northern step-fault zones of Baodao Sag in the eastern part of this basin,the fault bend,fault tip,and fault trench(fan)deltas were inherited and further developed,and the source-reservoir configuration conditions were favorable.Exploration deployment was carried out in the Baodao 21 area in the northern step-fault zone and the Yongle 10 area in the southern step-fault zone,where new discoveries in natural gas exploration have been realized.In the eastern part of this basin,the fault bend,fault tip,and fault gully(fan)deltas in the southern and northern fault step zones of Baodao Sag were successively developed,which were beneficial for favorable sourceereservoir configuration conditions.The natural gas exploration successes in the Baodao-21 area in the northern fault step zone and the Yongle-10 area in the southern fault step zone are beneficial for new discoveries in natural gas exploration in the Qiongdongnan Basin.
