Using field geological survey,drilling and seismic data,combined with the study of regional tectonic evolution and structural deformation,as well as lithological and sedimentary analysis,we reconstructed the basin fil...Using field geological survey,drilling and seismic data,combined with the study of regional tectonic evolution and structural deformation,as well as lithological and sedimentary analysis,we reconstructed the basin filling process and paleo-geography of north Tarim Basin in Early Cambrian,aiming to analyze the factors controlling the distribution and spatial architecture of the subsalt reservoir and source units and to define the favorable exploration direction.The Late Sinian tectonic activities in the northern Tarim Basin were characterized by different patterns in different areas,which controlled the sedimentary pattern in the Early Cambrian.The boundary faults of Nanhuaian rift basin in the south slope of Tabei uplift and the north slope of Tazhong uplift became reactivated in the Early Cambrian,forming two NEE and EW striking subsidence centers and depocenters,where the predicted thickness of the Yurtusi Formation could reach 250 meters.In the Xiaoerbulake period,the weak rimmed platform was developed in the hanging wall of syndepositional fault.Whereas the Nanhuaian rift system in the Tadong and Manxi areas were uplifted and destroyed in the Late Sinian,and appeared as gently slope transiting toward the subsidence center in the Early Cambrian.The former had the sedimentary features of hybrid facies platform and the latter had the sedimentary features of ramp platform.The black shale of the Yurtus Formation in the footwall of syndepositional fault and the reef bank of Xiaoerbulake Formation platform margin in the hanging wall in Early Cambrian constitute a predicable source-reservoir combination.The activity intensity of syndepositional fault controlled the thickness of black shale and the scale of the reef bank.It is suggested carrying out high accuracy seismic exploration to determine the location of Early Cambrian syndepositional faults,on this basis,to search the reef bank of Xiaoerbulake Formation along the faults westward,and then drill risk exploration wells at sites where traps are shallow in buried depth.展开更多
The prediction of sandstone distribution is the main target for hydrocarbon exploration and petroleum reservoir engineering,especially in a rift basin with a complex geological setting.During the Middle Eocene,the Don...The prediction of sandstone distribution is the main target for hydrocarbon exploration and petroleum reservoir engineering,especially in a rift basin with a complex geological setting.During the Middle Eocene,the Dongying and Yong’an deltas converged in the Dongying depression of the Bohai Bay Basin,eastern China.So far,studies on the control of the existing syndepositional faults on the deltaic sandbodies of the two confluence deltas have been largely neglected.In this contribution,the sedimentary characteristics and spatial distribution of the two deltas,converging in the Dongying depression,were determined.In addition,the morphodynamic controlling factors of the deposits of the two deltas were identified based on core examination,log analysis,and seismic data analysis.During delta progradation,the sandbodies of the initially separated deltas were affected by the development of syndepositional tensional faults,which eventually also influenced the distribution of the sandstone reservoirs.The results of this study can not only be applied to petroleum reservoir engineering but also provide important new information for the studies on delta sandbody all over the world.展开更多
基金Supported by the National Key Research and Development Program of China(2017YFC0603101)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA14010101)Scientific Research and Technological Development Project of PetroChina(2018A-01).
文摘Using field geological survey,drilling and seismic data,combined with the study of regional tectonic evolution and structural deformation,as well as lithological and sedimentary analysis,we reconstructed the basin filling process and paleo-geography of north Tarim Basin in Early Cambrian,aiming to analyze the factors controlling the distribution and spatial architecture of the subsalt reservoir and source units and to define the favorable exploration direction.The Late Sinian tectonic activities in the northern Tarim Basin were characterized by different patterns in different areas,which controlled the sedimentary pattern in the Early Cambrian.The boundary faults of Nanhuaian rift basin in the south slope of Tabei uplift and the north slope of Tazhong uplift became reactivated in the Early Cambrian,forming two NEE and EW striking subsidence centers and depocenters,where the predicted thickness of the Yurtusi Formation could reach 250 meters.In the Xiaoerbulake period,the weak rimmed platform was developed in the hanging wall of syndepositional fault.Whereas the Nanhuaian rift system in the Tadong and Manxi areas were uplifted and destroyed in the Late Sinian,and appeared as gently slope transiting toward the subsidence center in the Early Cambrian.The former had the sedimentary features of hybrid facies platform and the latter had the sedimentary features of ramp platform.The black shale of the Yurtus Formation in the footwall of syndepositional fault and the reef bank of Xiaoerbulake Formation platform margin in the hanging wall in Early Cambrian constitute a predicable source-reservoir combination.The activity intensity of syndepositional fault controlled the thickness of black shale and the scale of the reef bank.It is suggested carrying out high accuracy seismic exploration to determine the location of Early Cambrian syndepositional faults,on this basis,to search the reef bank of Xiaoerbulake Formation along the faults westward,and then drill risk exploration wells at sites where traps are shallow in buried depth.
基金financially supported by the ChinaASEAN Maritime Cooperation Fund Project (No.12120100500017001)the Key R&D Plan of Shandong Province (No.2017CXGC1608)。
文摘The prediction of sandstone distribution is the main target for hydrocarbon exploration and petroleum reservoir engineering,especially in a rift basin with a complex geological setting.During the Middle Eocene,the Dongying and Yong’an deltas converged in the Dongying depression of the Bohai Bay Basin,eastern China.So far,studies on the control of the existing syndepositional faults on the deltaic sandbodies of the two confluence deltas have been largely neglected.In this contribution,the sedimentary characteristics and spatial distribution of the two deltas,converging in the Dongying depression,were determined.In addition,the morphodynamic controlling factors of the deposits of the two deltas were identified based on core examination,log analysis,and seismic data analysis.During delta progradation,the sandbodies of the initially separated deltas were affected by the development of syndepositional tensional faults,which eventually also influenced the distribution of the sandstone reservoirs.The results of this study can not only be applied to petroleum reservoir engineering but also provide important new information for the studies on delta sandbody all over the world.
