The surface of sequence boundary is a negative record. Its recognition largely depends on the physics of the sediments below and above the boundaries, or on the different sedimentary structures are synthetic marks for...The surface of sequence boundary is a negative record. Its recognition largely depends on the physics of the sediments below and above the boundaries, or on the different sedimentary structures are synthetic marks for the sedimentation and tectonic movements in the sedimentary basin. The Qiangtang Basin that is in 5000m above the sea level is located in Northern Tibet. The Lazhulung—Jinshajiang suture zone now bound it to the north and the Bangong—Nujiang suture zone to the south. Three second\|order tectonic units have been distinguished, i.e. North Qiangtang depression, Central rise and South Qiangtang depression from north to south.The Upper Permian Riejuichaka Formation is built up of mudstone and mud\|limestone, which is represented by sediments in seamarsh. The Lower Triassic Kuanglu Formation, which exhibits the structure unconformable contact with the overlying Upper Permian strata, is characterized by terrigenous clastic rocks in the lower area and is carbonate rocks in the upwarding area and the Middle Triassic Kuangnan Formation. The Upper Triassic Xiachaka Formation consisting of terrigenous clastic rocks, carbonates rocks and mixed sediments, is confined to the uplift zones. The lower Jurassic volcanic rocks are deposited in continental rift. The middle and Upper Jurassic Yangshiping Group are conformable contact and assembled by the gypsum\|bearing terrigenous clastic rock formations and carbonate rock formation. The Middle Cretaceous and the Paleocene strata is built up of the terrigenous clastic rock formations.展开更多
The oil shale with marine origin was first reported in 1987 from Shuanghui of the Qiangtang region. Its depositional sequence consists of brown\|black oil shale interbedded massive to thin limestone. Eleven oil shale ...The oil shale with marine origin was first reported in 1987 from Shuanghui of the Qiangtang region. Its depositional sequence consists of brown\|black oil shale interbedded massive to thin limestone. Eleven oil shale beds occur and aggregated thickness is up to 47 38m. It deposit age is confined in middle Jurassic by fossils identification. Nine samples selected from horizons with high\|organic contents have been examined by organic geochemistry approach. The oil\|shale range widely in organic carbon content (Toc), average in 8 34%, maximum values reaching 26.12%. Toc are markedly varied in vertical section. The Upper and lower members are slightly low and increase in the middle. The oil\|shale sediments are characterized by high concentration in chloroform bitumen“A”(608～18707)×10 -6 )and total hydrocarbon ((311～5272)×10 -6 ).The Rock\|Eval T \|max data (434～440℃) and vitrinite reflectance values (0.88%～1.26%) indicate that oil\|shale sequence are mature in all samples. The organic matter is predominantly made up of typeⅡ kerogen.展开更多
文摘The surface of sequence boundary is a negative record. Its recognition largely depends on the physics of the sediments below and above the boundaries, or on the different sedimentary structures are synthetic marks for the sedimentation and tectonic movements in the sedimentary basin. The Qiangtang Basin that is in 5000m above the sea level is located in Northern Tibet. The Lazhulung—Jinshajiang suture zone now bound it to the north and the Bangong—Nujiang suture zone to the south. Three second\|order tectonic units have been distinguished, i.e. North Qiangtang depression, Central rise and South Qiangtang depression from north to south.The Upper Permian Riejuichaka Formation is built up of mudstone and mud\|limestone, which is represented by sediments in seamarsh. The Lower Triassic Kuanglu Formation, which exhibits the structure unconformable contact with the overlying Upper Permian strata, is characterized by terrigenous clastic rocks in the lower area and is carbonate rocks in the upwarding area and the Middle Triassic Kuangnan Formation. The Upper Triassic Xiachaka Formation consisting of terrigenous clastic rocks, carbonates rocks and mixed sediments, is confined to the uplift zones. The lower Jurassic volcanic rocks are deposited in continental rift. The middle and Upper Jurassic Yangshiping Group are conformable contact and assembled by the gypsum\|bearing terrigenous clastic rock formations and carbonate rock formation. The Middle Cretaceous and the Paleocene strata is built up of the terrigenous clastic rock formations.
文摘The oil shale with marine origin was first reported in 1987 from Shuanghui of the Qiangtang region. Its depositional sequence consists of brown\|black oil shale interbedded massive to thin limestone. Eleven oil shale beds occur and aggregated thickness is up to 47 38m. It deposit age is confined in middle Jurassic by fossils identification. Nine samples selected from horizons with high\|organic contents have been examined by organic geochemistry approach. The oil\|shale range widely in organic carbon content (Toc), average in 8 34%, maximum values reaching 26.12%. Toc are markedly varied in vertical section. The Upper and lower members are slightly low and increase in the middle. The oil\|shale sediments are characterized by high concentration in chloroform bitumen“A”(608～18707)×10 -6 )and total hydrocarbon ((311～5272)×10 -6 ).The Rock\|Eval T \|max data (434～440℃) and vitrinite reflectance values (0.88%～1.26%) indicate that oil\|shale sequence are mature in all samples. The organic matter is predominantly made up of typeⅡ kerogen.
