The depth to detachment level is a critical factor affecting the quality of structural modeling in fold and thrust belts. There are several detachment levels developed in the Kuqa depression. Based on the excess-area ...The depth to detachment level is a critical factor affecting the quality of structural modeling in fold and thrust belts. There are several detachment levels developed in the Kuqa depression. Based on the excess-area diagram, this paper concerns mainly the calculation of the depth to detachment in the Kuqa depression. The result demonstrates that the detachment levels are situated in different strata in varying zones, such as the Paleogene Kugeliemu Formation, the Paleozoic and the crystalline basement. The calculated depth to detachment level is very helpful for testing whether a structural interpretation is reasonable and for defining the depth of deeper detachment levels which were not discerned in seismic profiles.展开更多
The evolution of the global Tethys Sea can be classified into three stages, Proto-Tethys, Paleo-Tethys and Neo-Tethys. The Tethyan realm has distinctive features of zonations and segmentations along north-south and ea...The evolution of the global Tethys Sea can be classified into three stages, Proto-Tethys, Paleo-Tethys and Neo-Tethys. The Tethyan realm has distinctive features of zonations and segmentations along north-south and east-west, respectively, and has variable richness in oil and gas. The petroleum geological conditions of Tethys are complicated, partly represented by multi-layer of source and seal rocks, and reservoirs. The hydrocarbon accumulation elements and periods of the Tethyan realm show gradually younger from west to east and north to south. South China is located in the north belt and Yangtze segment of the Tethyan realm, and its polycyclic tectonic movements were governed by the Tethyan and Pacific realms. The blocks in South China rotated clockwise and counter-clockwise during their drift northward from Gondwana. The belts and segmentations of Tethys in South China are also clear, with six tectonic belts including: Chuxiong-Sichuan; middle Guizhou-Hunan-Hubei; lower Yangtze; Xuefeng-Jiangnan; Guangxi-Hunan-Jiangxi; and Cathaysia. Numerous faults, including compressional, compressional-shear, extensional, extensional-shear and shear are well developed in South China. The fault strikes are mainly NE, NW and NS, in which the NE is the dominant direction. Lower, middle and upper hydrocarbon assemblages, respectively corresponding to Proto-, Paleo- and Neo-Tethys, formed in the Tethyan realm of South China with the lower and middle having excellent hydrocarbon accumulation conditions. An integrated analysis of tectonic evolution, superimposed deformation and later hydrocarbon preservation shows that during the Neo-Tethyan stage in South China, continental sediments were deposited and experienced intense tectonic deformation, which had resulted in different hydrocarbon pool-forming features from those of the Neo-Tethyan realm.展开更多
With many types of salt structures developed in the Lower Cretaceous Aptian Formation,the passive continental marginal basins in the middle segment of the south Atlantic are hot areas of deep-water petroleum explorati...With many types of salt structures developed in the Lower Cretaceous Aptian Formation,the passive continental marginal basins in the middle segment of the south Atlantic are hot areas of deep-water petroleum exploration.Based on analysis of differential deformations of salt structures,the influences of the inclination of subsalt slope,subsalt topographic reliefs and basement uplifting on the formation of salt structures were analyzed by physical modeling in this work.The experimental results show that the subsalt slopes in the middle West Africa basins are steeper,so the salt rock is likely to rapidly flow towards the ocean to form larger and fewer salt diapirs.In the Santos and Campos basins,the basement uplifts outside the basins are far from the provenances,which is conducive to the intrusion and accumulation of salt rock on the top of the basement uplifts.In contrast,in the middle West Africa,the basement uplifts are close to the basin margin,the residual salt layers above them are thin,and small triangular salt structures develop on both sides of the uplifts.Moreover,the uplifting of the African plate is also conducive to the full development of salt diapirs in the middle West Africa and results in large-scale thrust faults and folds in the front compressional zone.展开更多
基金the National Natural Science Foundation of China(No.40472107,40172076)the Foundation of Key Laboratory of Education Ministry for Hydrocarbon Accumulation Mechanism(China University of Petroleum)(Grant No.2003-02)+1 种基金the National Major Fundamental Research and Development Project(2005CB422107,G1999043305)the Tarim 0ilfield Company Project(Grant No.41004050009).
文摘The depth to detachment level is a critical factor affecting the quality of structural modeling in fold and thrust belts. There are several detachment levels developed in the Kuqa depression. Based on the excess-area diagram, this paper concerns mainly the calculation of the depth to detachment in the Kuqa depression. The result demonstrates that the detachment levels are situated in different strata in varying zones, such as the Paleogene Kugeliemu Formation, the Paleozoic and the crystalline basement. The calculated depth to detachment level is very helpful for testing whether a structural interpretation is reasonable and for defining the depth of deeper detachment levels which were not discerned in seismic profiles.
基金funded jointly by the National Natural Science Foundation of China (No.40802030)the National Major Fundamental Research and Development Project (No.2005CB422107)
文摘The evolution of the global Tethys Sea can be classified into three stages, Proto-Tethys, Paleo-Tethys and Neo-Tethys. The Tethyan realm has distinctive features of zonations and segmentations along north-south and east-west, respectively, and has variable richness in oil and gas. The petroleum geological conditions of Tethys are complicated, partly represented by multi-layer of source and seal rocks, and reservoirs. The hydrocarbon accumulation elements and periods of the Tethyan realm show gradually younger from west to east and north to south. South China is located in the north belt and Yangtze segment of the Tethyan realm, and its polycyclic tectonic movements were governed by the Tethyan and Pacific realms. The blocks in South China rotated clockwise and counter-clockwise during their drift northward from Gondwana. The belts and segmentations of Tethys in South China are also clear, with six tectonic belts including: Chuxiong-Sichuan; middle Guizhou-Hunan-Hubei; lower Yangtze; Xuefeng-Jiangnan; Guangxi-Hunan-Jiangxi; and Cathaysia. Numerous faults, including compressional, compressional-shear, extensional, extensional-shear and shear are well developed in South China. The fault strikes are mainly NE, NW and NS, in which the NE is the dominant direction. Lower, middle and upper hydrocarbon assemblages, respectively corresponding to Proto-, Paleo- and Neo-Tethys, formed in the Tethyan realm of South China with the lower and middle having excellent hydrocarbon accumulation conditions. An integrated analysis of tectonic evolution, superimposed deformation and later hydrocarbon preservation shows that during the Neo-Tethyan stage in South China, continental sediments were deposited and experienced intense tectonic deformation, which had resulted in different hydrocarbon pool-forming features from those of the Neo-Tethyan realm.
基金Supported by the China National Science and Technology Major Project(2016ZX05033,2016ZX05026-007)National Natural Science Foundation of China(42072149)。
文摘With many types of salt structures developed in the Lower Cretaceous Aptian Formation,the passive continental marginal basins in the middle segment of the south Atlantic are hot areas of deep-water petroleum exploration.Based on analysis of differential deformations of salt structures,the influences of the inclination of subsalt slope,subsalt topographic reliefs and basement uplifting on the formation of salt structures were analyzed by physical modeling in this work.The experimental results show that the subsalt slopes in the middle West Africa basins are steeper,so the salt rock is likely to rapidly flow towards the ocean to form larger and fewer salt diapirs.In the Santos and Campos basins,the basement uplifts outside the basins are far from the provenances,which is conducive to the intrusion and accumulation of salt rock on the top of the basement uplifts.In contrast,in the middle West Africa,the basement uplifts are close to the basin margin,the residual salt layers above them are thin,and small triangular salt structures develop on both sides of the uplifts.Moreover,the uplifting of the African plate is also conducive to the full development of salt diapirs in the middle West Africa and results in large-scale thrust faults and folds in the front compressional zone.