The lower Tertiary Eh3 is divided into two sections： the upper members of Eh3 and the lower members of Eh3 in the Biyang Depression. The first section is generally regarded as a key target of oil and gas exploration,...The lower Tertiary Eh3 is divided into two sections： the upper members of Eh3 and the lower members of Eh3 in the Biyang Depression. The first section is generally regarded as a key target of oil and gas exploration, but the resource potential of the lower members of Eh3 has been neglected. We have obtained new knowledge about Eh3 from comprehensive geological research. The lower members of Eh3 are high-quality and main source rocks, which have good oil and gas resource potential. This is a new direction for oil and gas exploration. The geochemistry characteristics of source rocks of the lower members of Eh3 in the lower Tertiary of the Biyang Depression were analyzed in detail. A basin modeling method was applied to hydrocarbon generation of the lower and upper members of Eh3 source rocks, the oil and gas resource potential was comparatively analyzed, and then favorable tectonic zones were pointed out. In the lower members of Eh3, a set of semi-deep lake to deep lake high-quality source rocks occurs rich in algae organisms, mainly of type II1, with a high abundance of organic matter. Most of the source rocks are just in the peak stage of hydrocarbon generation, which is a favorable foundation for forming abundant oil and gas resources in the Biyang Depression. The comparative analysis of the hydrocarbon- generation quantities between lower and upper members of the Eh3 source rocks shows that the lower members of Eh3 have good oil and gas resource potential, and the hydrocarbon-generation quantity accounts for 51% of the total in Eh3. Specifically, the oil-generating quantity accounts for 50% of the total and the gas-generating quantity accounts for two thirds of the total. Therefore, source rocks in the lower members of Eh3 of the Biyang Depression have good oil and gas resource potential, which is a key factor for future deep oil and gas exploration.展开更多
The Qiongdongnan Basin and Zhujiang River（Pearl River） Mouth Basin, important petroliferous basins in the northern South China Sea, contain abundant oil and gas resource. In this study, on basis of discussing impact...The Qiongdongnan Basin and Zhujiang River（Pearl River） Mouth Basin, important petroliferous basins in the northern South China Sea, contain abundant oil and gas resource. In this study, on basis of discussing impact of oil-base mud on TOC content and Rock-Eval parameters of cutting shale samples, the authors did comprehensive analysis of source rock quality, thermal evolution and control effect of source rock in gas accumulation of the Qiongdongnan and the Zhujiang River Mouth Basins. The contrast analysis of TOC contents and Rock-Eval parameters before and after extraction for cutting shale samples indicates that except for a weaker impact on Rock-Eval parameter S2, oil-base mud has certain impact on Rock-Eval S1, Tmax and TOC contents. When concerning oil-base mud influence on source rock geochemistry parameters, the shales in the Yacheng/Enping,Lingshui/Zhuhai and Sanya/Zhuhai Formations have mainly Type Ⅱ and Ⅲ organic matter with better gas potential and oil potential. The thermal evolution analysis suggests that the depth interval of the oil window is between 3 000 m and 5 000 m. Source rocks in the deepwater area have generated abundant gas mainly due to the late stage of the oil window and the high-supper mature stage. Gas reservoir formation condition analysis made clear that the source rock is the primary factor and fault is a necessary condition for gas accumulation. Spatial coupling of source, fault and reservoir is essential for gas accumulation and the inside of hydrocarbon-generating sag is future potential gas exploration area.展开更多
The Taoudeni Basin is a typical and steady intracratonic basin in Mauritania, northwest Africa. There are six sets of potential source rocks and five regional unconformable surfaces of the Infracambrian and Paleozoic ...The Taoudeni Basin is a typical and steady intracratonic basin in Mauritania, northwest Africa. There are six sets of potential source rocks and five regional unconformable surfaces of the Infracambrian and Paleozoic developed in the basin. We used seismic stratigraphic correlation to recover the denudation thickness of formations at a particular well location. Studies of the hydrocarbon generation history of the basin illustrate that hydrocarbon migration and accumulation occurred in the end of the Carboniferous, and after that, the whole basin suffered denudation for a long period of time. Because there is no thick Mesozoic overburden in the basin, the Silurian source rocks could not generate hydrocarbon in the Mesozoic era for the second time. Consequently, the prospects for successful hydrocarbon exploration in the basin are not good.展开更多
文摘The lower Tertiary Eh3 is divided into two sections： the upper members of Eh3 and the lower members of Eh3 in the Biyang Depression. The first section is generally regarded as a key target of oil and gas exploration, but the resource potential of the lower members of Eh3 has been neglected. We have obtained new knowledge about Eh3 from comprehensive geological research. The lower members of Eh3 are high-quality and main source rocks, which have good oil and gas resource potential. This is a new direction for oil and gas exploration. The geochemistry characteristics of source rocks of the lower members of Eh3 in the lower Tertiary of the Biyang Depression were analyzed in detail. A basin modeling method was applied to hydrocarbon generation of the lower and upper members of Eh3 source rocks, the oil and gas resource potential was comparatively analyzed, and then favorable tectonic zones were pointed out. In the lower members of Eh3, a set of semi-deep lake to deep lake high-quality source rocks occurs rich in algae organisms, mainly of type II1, with a high abundance of organic matter. Most of the source rocks are just in the peak stage of hydrocarbon generation, which is a favorable foundation for forming abundant oil and gas resources in the Biyang Depression. The comparative analysis of the hydrocarbon- generation quantities between lower and upper members of the Eh3 source rocks shows that the lower members of Eh3 have good oil and gas resource potential, and the hydrocarbon-generation quantity accounts for 51% of the total in Eh3. Specifically, the oil-generating quantity accounts for 50% of the total and the gas-generating quantity accounts for two thirds of the total. Therefore, source rocks in the lower members of Eh3 of the Biyang Depression have good oil and gas resource potential, which is a key factor for future deep oil and gas exploration.
基金The National Key Science and Technology Special Project(13th Five Year Plan)of the Key Technology of Gas and Oil Exploration in Offshore Deep Water Area(Phase 3)under contract No.2016Zx05026
文摘The Qiongdongnan Basin and Zhujiang River（Pearl River） Mouth Basin, important petroliferous basins in the northern South China Sea, contain abundant oil and gas resource. In this study, on basis of discussing impact of oil-base mud on TOC content and Rock-Eval parameters of cutting shale samples, the authors did comprehensive analysis of source rock quality, thermal evolution and control effect of source rock in gas accumulation of the Qiongdongnan and the Zhujiang River Mouth Basins. The contrast analysis of TOC contents and Rock-Eval parameters before and after extraction for cutting shale samples indicates that except for a weaker impact on Rock-Eval parameter S2, oil-base mud has certain impact on Rock-Eval S1, Tmax and TOC contents. When concerning oil-base mud influence on source rock geochemistry parameters, the shales in the Yacheng/Enping,Lingshui/Zhuhai and Sanya/Zhuhai Formations have mainly Type Ⅱ and Ⅲ organic matter with better gas potential and oil potential. The thermal evolution analysis suggests that the depth interval of the oil window is between 3 000 m and 5 000 m. Source rocks in the deepwater area have generated abundant gas mainly due to the late stage of the oil window and the high-supper mature stage. Gas reservoir formation condition analysis made clear that the source rock is the primary factor and fault is a necessary condition for gas accumulation. Spatial coupling of source, fault and reservoir is essential for gas accumulation and the inside of hydrocarbon-generating sag is future potential gas exploration area.
文摘The Taoudeni Basin is a typical and steady intracratonic basin in Mauritania, northwest Africa. There are six sets of potential source rocks and five regional unconformable surfaces of the Infracambrian and Paleozoic developed in the basin. We used seismic stratigraphic correlation to recover the denudation thickness of formations at a particular well location. Studies of the hydrocarbon generation history of the basin illustrate that hydrocarbon migration and accumulation occurred in the end of the Carboniferous, and after that, the whole basin suffered denudation for a long period of time. Because there is no thick Mesozoic overburden in the basin, the Silurian source rocks could not generate hydrocarbon in the Mesozoic era for the second time. Consequently, the prospects for successful hydrocarbon exploration in the basin are not good.
