An integrated interpretation of processed 3D seismic data,a suite of well logs,biostratigraphic data and core photographs of AMO Field,deep offshore Niger Delta,is carried out for the sequence stratigraphic analysis o...An integrated interpretation of processed 3D seismic data,a suite of well logs,biostratigraphic data and core photographs of AMO Field,deep offshore Niger Delta,is carried out for the sequence stratigraphic analysis of strata penetrated by wells.Lithologic and key stratigraphic surfaces,that is,the maximum flooding surfaces(MFSs)and sequence boundaries(SBs),are identified based on bioevents and log motifs.Biostratigraphic data help the delineation of MFSs and SBs,as well as dating,determination of depositional environment and paleobathymetry.The sequence stratigraphic study reveals seven MFSs(of 13.0 Ma,11.0 Ma,9.5 Ma,7.4 Ma,5.8 Ma,5.0 Ma and 2.7 Ma)and six SBs(of 12.1 Ma,10.3 Ma,8.5 Ma,6.3 Ma,5.5 Ma and 4.2 Ma).The key stratigraphic surfaces identified involve three depositional sequences characterized by lowstand,transgressive and highstand system tracts respectively.The studied section is deposited in a deepwater environment ranging from Lower to Upper Bathyal and can be dated back to the Middle Miocene-Middle Pliocene in age.Seven faults and two horizons(corresponding to reservoir units)are identified and mapped across the seismic data volume to establish a continuity of the reservoir to areas lacking well control.The established sequence stratigraphic framework displays successions of sediments(system tracts)where the reservoir sand units of the lowstand and highstand system tracts are of hydrocarbon prospective units in the field.展开更多
Two significant biological and geological events happened during the Ordovician,i.e.,the great Ordovician biodiversification event(GOBE;Webby et al.,2004)and the end-Ordovician mass extinction(Sheehan,2001).The two ev...Two significant biological and geological events happened during the Ordovician,i.e.,the great Ordovician biodiversification event(GOBE;Webby et al.,2004)and the end-Ordovician mass extinction(Sheehan,2001).The two events were remarkably well recorded in South China and manifested by the diversity history of major marine fossil groups(e.g.,Chen et al.,2004;Rong and Zhan,2004;Rong et al.,2007).展开更多
Detailed radiolarian biostratigraphy in the Plio-Pleistocene was analyzed by using samples from IODP Site U1340 that was drilled to a core depth of 604 m in the southern Bering Sea.A total of 227 species belonging to ...Detailed radiolarian biostratigraphy in the Plio-Pleistocene was analyzed by using samples from IODP Site U1340 that was drilled to a core depth of 604 m in the southern Bering Sea.A total of 227 species belonging to 102 genera were identified.Based on the distributions of the radiolarian index species at Site U1340,five radiolarian zones since the Pliocene were established in the southern Bering Sea for the first time,and 25 radiolarian bioevents were recognized.Their ages were estimated on the basis of the age-depth plot that was constructed by the synthetical datum of the effective biostratigraphic and magnetostratigraphic events.The radiolarian zones at Site U1340 were systematically compared with those in its adjacent regions since the late Early Pliocene,which further improved and interpreted the biostratigraphic datum as well as their correlations in the middle-high latitude of the North Pacific.In addition,the comparative results of radiolarian zones show that Botryostrobus aquilonaris Zone emended in this paper is equivalent to the upper part of the same zone defined by Hays,1970,and Druppatractus irregularis-Dorydruppa bensoni Zone as well as Spongodiscus sp.Zone,newly proposed in this paper,are well correlated with Cycladophora sakaii Zone and Stylatractus universus Zone in the subarctic North Pacific,respectively.展开更多
文摘An integrated interpretation of processed 3D seismic data,a suite of well logs,biostratigraphic data and core photographs of AMO Field,deep offshore Niger Delta,is carried out for the sequence stratigraphic analysis of strata penetrated by wells.Lithologic and key stratigraphic surfaces,that is,the maximum flooding surfaces(MFSs)and sequence boundaries(SBs),are identified based on bioevents and log motifs.Biostratigraphic data help the delineation of MFSs and SBs,as well as dating,determination of depositional environment and paleobathymetry.The sequence stratigraphic study reveals seven MFSs(of 13.0 Ma,11.0 Ma,9.5 Ma,7.4 Ma,5.8 Ma,5.0 Ma and 2.7 Ma)and six SBs(of 12.1 Ma,10.3 Ma,8.5 Ma,6.3 Ma,5.5 Ma and 4.2 Ma).The key stratigraphic surfaces identified involve three depositional sequences characterized by lowstand,transgressive and highstand system tracts respectively.The studied section is deposited in a deepwater environment ranging from Lower to Upper Bathyal and can be dated back to the Middle Miocene-Middle Pliocene in age.Seven faults and two horizons(corresponding to reservoir units)are identified and mapped across the seismic data volume to establish a continuity of the reservoir to areas lacking well control.The established sequence stratigraphic framework displays successions of sediments(system tracts)where the reservoir sand units of the lowstand and highstand system tracts are of hydrocarbon prospective units in the field.
基金granted by the National Natural Science Foundation of China(Grant Nos.41802017 and U1562213)the National Science and Technology Major Project of China(Grant No.2017ZX05035002-001)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB26000000).
文摘Two significant biological and geological events happened during the Ordovician,i.e.,the great Ordovician biodiversification event(GOBE;Webby et al.,2004)and the end-Ordovician mass extinction(Sheehan,2001).The two events were remarkably well recorded in South China and manifested by the diversity history of major marine fossil groups(e.g.,Chen et al.,2004;Rong and Zhan,2004;Rong et al.,2007).
基金supported by the National Natural Science Foundation of China(Grant Nos.41076026,40906030,41276051&41030859)the National Key Basic Research Program of China(Grant No.2013CB956102)+1 种基金the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.SQ200808)the Key Technology Research on Investigations of Ocean Drilling Sites(Grant No.2008AA093001)
文摘Detailed radiolarian biostratigraphy in the Plio-Pleistocene was analyzed by using samples from IODP Site U1340 that was drilled to a core depth of 604 m in the southern Bering Sea.A total of 227 species belonging to 102 genera were identified.Based on the distributions of the radiolarian index species at Site U1340,five radiolarian zones since the Pliocene were established in the southern Bering Sea for the first time,and 25 radiolarian bioevents were recognized.Their ages were estimated on the basis of the age-depth plot that was constructed by the synthetical datum of the effective biostratigraphic and magnetostratigraphic events.The radiolarian zones at Site U1340 were systematically compared with those in its adjacent regions since the late Early Pliocene,which further improved and interpreted the biostratigraphic datum as well as their correlations in the middle-high latitude of the North Pacific.In addition,the comparative results of radiolarian zones show that Botryostrobus aquilonaris Zone emended in this paper is equivalent to the upper part of the same zone defined by Hays,1970,and Druppatractus irregularis-Dorydruppa bensoni Zone as well as Spongodiscus sp.Zone,newly proposed in this paper,are well correlated with Cycladophora sakaii Zone and Stylatractus universus Zone in the subarctic North Pacific,respectively.
