As one of the basins with extremely abundant oil and gas resources in South China Sea,the Wan'an Basin has attracted great attention from domestic and international geologists and hydrocarbon explorers.Currently,t...As one of the basins with extremely abundant oil and gas resources in South China Sea,the Wan'an Basin has attracted great attention from domestic and international geologists and hydrocarbon explorers.Currently,the sequence stratigraphic framework,distribution of sedimentary systems and sedimentary filling evolution of the Wan'an Basin are still not clear,consequently,it bring some difficulties for hydrocarbon exploration.Based on the palaeobios,well drilling,well logging,and seismic and other data,the sequence stratigraphic framework of the Wan'an Basin is established,and the sequence interfaces of T100,T60,T50,T40 and T30 in this study are identified.On this basis,the sedimentary environment and sedimentary filling evolution of the Wan'an Basin are systematically analyzed.The results show that the basin had experienced three tectonic evolution periods since Cenozoic,i.e.,the OligoceneeEarly Miocene extensional fault-depression period,Middle Miocene strike-slip reformation period and Late Miocene eQuaternary regional depression period.Thereinto,the provenance in the extensional faultdepression period(OligoceneeEarly Miocene)was mainly from the western uplift of the basin,where the deltaeshore-shallow lacustrineebathylimnetic sedimentary system during Early Oligocene and delta elittoral-neritic sedimentary system during Late OligoceneeEarly Miocene were developed respectively.The provenance during the strike-slip reformation period(Middle Miocene)was still mainly from the western uplift of the basin,where the deltaelittoral-neriticecarbonate platform sedimentary system was developed,and the carbonate platform began to develop abundantly.The provenance during the regional depression period(Late MioceneeQuaternary)is mainly supplied by input of the western distal large rivers,the deltaelittoral-shallow seaecarbonate platformebathyal sea sedimentary system was developed in the Late Miocene,and the shelf-margin deltaecontinental slopeebathyal sea sedimentary system was developed during Pliocene-Quaternary.Therefore,the Wan'an Basin has a favorable hydrocarbon resource potential.展开更多
基金supported by the National Science and Technology Major Project of China(No.2016ZX05026-004)the National Natural Science Foundation of China(No.91528303).
文摘As one of the basins with extremely abundant oil and gas resources in South China Sea,the Wan'an Basin has attracted great attention from domestic and international geologists and hydrocarbon explorers.Currently,the sequence stratigraphic framework,distribution of sedimentary systems and sedimentary filling evolution of the Wan'an Basin are still not clear,consequently,it bring some difficulties for hydrocarbon exploration.Based on the palaeobios,well drilling,well logging,and seismic and other data,the sequence stratigraphic framework of the Wan'an Basin is established,and the sequence interfaces of T100,T60,T50,T40 and T30 in this study are identified.On this basis,the sedimentary environment and sedimentary filling evolution of the Wan'an Basin are systematically analyzed.The results show that the basin had experienced three tectonic evolution periods since Cenozoic,i.e.,the OligoceneeEarly Miocene extensional fault-depression period,Middle Miocene strike-slip reformation period and Late Miocene eQuaternary regional depression period.Thereinto,the provenance in the extensional faultdepression period(OligoceneeEarly Miocene)was mainly from the western uplift of the basin,where the deltaeshore-shallow lacustrineebathylimnetic sedimentary system during Early Oligocene and delta elittoral-neritic sedimentary system during Late OligoceneeEarly Miocene were developed respectively.The provenance during the strike-slip reformation period(Middle Miocene)was still mainly from the western uplift of the basin,where the deltaelittoral-neriticecarbonate platform sedimentary system was developed,and the carbonate platform began to develop abundantly.The provenance during the regional depression period(Late MioceneeQuaternary)is mainly supplied by input of the western distal large rivers,the deltaelittoral-shallow seaecarbonate platformebathyal sea sedimentary system was developed in the Late Miocene,and the shelf-margin deltaecontinental slopeebathyal sea sedimentary system was developed during Pliocene-Quaternary.Therefore,the Wan'an Basin has a favorable hydrocarbon resource potential.
