Geological mapping,interpreted cross sections,structural analyses and residual thickness maps were used to characterize the evolution of stress setting,structure and stratigraphic distribution of the Chepaizi Uplift,w...Geological mapping,interpreted cross sections,structural analyses and residual thickness maps were used to characterize the evolution of stress setting,structure and stratigraphic distribution of the Chepaizi Uplift,which is a NW-SE trending structure located in the Western Junggar Basin.The NS-trending faults show an important transpressional phase during the Late Permian,as demonstrated by tectonic stress field and stratigraphic thickness variations.A major compressional thrusting and strike-slip phase during the Late Jurassic created a series of NW-SE faults that originated by the large-scale uplift event in the Northern Tianshan.Faults were reactivated as thrust and dextral strike-slip faults.In addition,the angular unconformity observed between Jurassic and Cretaceous provide evidence of this tectonic event.Lots of normal faults indicate that the area records southward tilting and regional derived extensional stress that took place during the Neogene.Before that,thick Early Cenozoic strata are widely deposited.The balanced cross-section highlights the evolution of stress setting and stratigraphic distribution of the Chepaizi Uplift.展开更多
Well che89,located in the Chepaizi area in the northwest margin of Junggar basin,acquires high production industrial oil flow,which is an important breakthrough in the exploration of the south foreland slope area of J...Well che89,located in the Chepaizi area in the northwest margin of Junggar basin,acquires high production industrial oil flow,which is an important breakthrough in the exploration of the south foreland slope area of Junggar basin. The Chepaizi area is near two hydrocarbon generation depressions of Sikeshu and Shawan,which have sets of hydrocarbon source rock of Carboniferous to Jurassic as well as Upper Tertiary. Geological and geochemical parameters are proper for the accumulation of mixed source crude oil. Carbon isotope,group composition and biomarkers of crude oil in Upper Tertiary of well Che89 show that the features of crude oil in Upper Tertiary Shawan Formation are between that of Permian and Jurassic,some of them are similar to these two,and some are of difference,they should be the mixed source of Permian and Jurassic. Geochemical analysis and geological study show that sand extract of Lower Tertiary Wulunguhe Formation has the same source as the crude oil and sand extract of Upper Tertiary Shawan Formation,but they are not charged in the same period. Oil/gas of Wulunguhe Formation is charged before Upper Tertiary sedimentation,and suffered serious biodegradation and oxidation and rinsing,which provide a proof in another aspect that the crude oil of Upper Tertiary Shawan Formation of well Che89 is not from hydrocarbon source rock of Lower Tertiary.展开更多
基金financially supported by the Natural Sciences Foundation of China(Chen S.,grant number 41502208)Science Foundation of China University of Petroleum(Chen S.,grant number 2462017BJB01)CNPC Innovation Foundation(Chen S.,grant number 2017D-5007-0103)
文摘Geological mapping,interpreted cross sections,structural analyses and residual thickness maps were used to characterize the evolution of stress setting,structure and stratigraphic distribution of the Chepaizi Uplift,which is a NW-SE trending structure located in the Western Junggar Basin.The NS-trending faults show an important transpressional phase during the Late Permian,as demonstrated by tectonic stress field and stratigraphic thickness variations.A major compressional thrusting and strike-slip phase during the Late Jurassic created a series of NW-SE faults that originated by the large-scale uplift event in the Northern Tianshan.Faults were reactivated as thrust and dextral strike-slip faults.In addition,the angular unconformity observed between Jurassic and Cretaceous provide evidence of this tectonic event.Lots of normal faults indicate that the area records southward tilting and regional derived extensional stress that took place during the Neogene.Before that,thick Early Cenozoic strata are widely deposited.The balanced cross-section highlights the evolution of stress setting and stratigraphic distribution of the Chepaizi Uplift.
基金Supported by National Natural Science Foundation of China (Grant Nos. 40602013 and 40572078)Doctor’s Foundation (Grant No. 20060489002)
文摘Well che89,located in the Chepaizi area in the northwest margin of Junggar basin,acquires high production industrial oil flow,which is an important breakthrough in the exploration of the south foreland slope area of Junggar basin. The Chepaizi area is near two hydrocarbon generation depressions of Sikeshu and Shawan,which have sets of hydrocarbon source rock of Carboniferous to Jurassic as well as Upper Tertiary. Geological and geochemical parameters are proper for the accumulation of mixed source crude oil. Carbon isotope,group composition and biomarkers of crude oil in Upper Tertiary of well Che89 show that the features of crude oil in Upper Tertiary Shawan Formation are between that of Permian and Jurassic,some of them are similar to these two,and some are of difference,they should be the mixed source of Permian and Jurassic. Geochemical analysis and geological study show that sand extract of Lower Tertiary Wulunguhe Formation has the same source as the crude oil and sand extract of Upper Tertiary Shawan Formation,but they are not charged in the same period. Oil/gas of Wulunguhe Formation is charged before Upper Tertiary sedimentation,and suffered serious biodegradation and oxidation and rinsing,which provide a proof in another aspect that the crude oil of Upper Tertiary Shawan Formation of well Che89 is not from hydrocarbon source rock of Lower Tertiary.
