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921.
The geochemical characteristics and origin of crude oils in the Kekeya Oilfield,Xinjiang, China 总被引:2,自引:2,他引:0
GC/MS and GC/MS/MS techniques were employed to describe the characteristics of biomarker assemblages in two sets of hydrocarbon source rocks, Jurassic and Permian, in southwestern Tarim, and the parameters for the classification of the two sets of hydrocarbon source rocks have been established. It is found that diahopane and C30-unknown terpane are abundant in Permian samples, the contents of diahopane in Jurassic samples are relatively low, and terpenoids have been detected in Jurassic samples but not in Permian source rock samples. Kekeya crude oils are abundant in diahopane and C30-unknown terpane. The results of fine oil-rock correlation indicated that Kekeya crude oils were derived mainly from the Permian hydrocarbon source rocks. However, a small amount of diterpenoid was detected in the crude oils, indicating that the Jurassic hydrocarbon source rocks also made a certain contribution to Kekeya crude oils. 相似文献
922.
Peishu Zong Jianping Tang Shuyu Wang Lingyun Xie Jianwei Yu Yunqian Zhu Xiaorui Niu Chao Li 《Theoretical and Applied Climatology》2017,129(3-4):1263-1277
Theoretical and Applied Climatology - The parameterization of physical processes is one of the critical elements to properly simulate the regional climate over eastern China. It is essential to... 相似文献
923.
Li-Yang Xiong Guo-An Tang Ye-Qing Qian 《International journal of geographical information science》2017,31(2):387-404
Residual upland planation surfaces serve as strong evidence of peneplains during long intervals of base-level stability in the peneplanation process. Multi-stage planation surfaces could aid the calculation of uplift rates and the reconstruction of upland plateau evolution. However, most planation surfaces have been damaged by crustal uplift, tectonic deformation, and surface erosion, thus increasing the difficulty in automatically identifying residual planation surfaces. This study proposes a peak-cluster assessment method for the automatic identification of potential upland planation surfaces. It consists of two steps: peak extraction and peak-cluster characterization. Three critical parameters, namely, landform planation index (LPI), peak elevation standard deviation, and peak density, are employed to assess peak clusters. The proposed method is applied and validated in five case areas in the Tibetan Plateau using a Shuttle Radar Topography Mission digital elevation model (SRTM DEM) with 3 arc-second resolution. Results show that the proposed method can effectively extract potential planation surfaces, which are found to be stable with different resolutions of DEM data. A significant planation characteristic can be obtained in the relatively flat areas of the Gangdise–Nyainqentanglha Mountains and Qaidam Basin. Several vestiges of potential former planation areas are also extracted in the hilly-gully areas of the western part of the Himalaya Mountains, the northern part of the Tangula–Hengduan Mountains, and the northeastern part of the Kunlun–Qinling Mountains despite the absence of significant topographical features characterized by low slope angles or low terrain reliefs. Vestiges of planation surfaces are also identified in these hilly-gully upland areas. Hence, the proposed method can be effectively used to extract potential upland planation surfaces not only in flat areas but also in hilly-gully areas. 相似文献
924.
925.
Jiang Yicheng Tang Jiaxiang School of Civil Engineering Huazhong University of Science Technology Wuhan 《中国地质大学学报(英文版)》2001,12(1)
INTRODUCTIONConcept of base isolation has attracted considerable attention in recent years (Sun et al., 1994). The basic isolationsystem consists of an array of bearings between the base of thebuilding and its foundation. It shifts the fundamental frequencyof the structure away from the energetic region of the earthquake spectrum and limits the earthquake energy transmitted tothe superstructure (Tang and Liu, 1993 ). Base isolation isused widely to protect structures from the destructive… 相似文献
926.
本文根据软件工程的原理和方法阐述了县级泥石流信息系统的建立过程,并讨论了其应用,主要包括数据库管理系统的应用,用图形库的应用,系统支持下的泥石流危险度分区,泥石流两类分别判别模式的建立。 相似文献
927.
河东煤田地史—热史模拟与煤变质演化 总被引:13,自引:0,他引:13
河东煤田是华北石炭二叠纪重要煤田之一.本文采用盆地数值模拟方法,建立了煤田地史一热史模型,恢复了煤变质演化历程,总结出煤级分布规律。 相似文献
928.
汤中书 《地震地磁观测与研究》1992,13(2):74-78
本文着重讨论了地震通信电台的合理布网,电台天线和电台架设中的问题。并提出了电台架设中应该注意解决的一些共性问题,其目的是为了对地震通信用电台架设的最佳方法进行一次试验性的初探。 相似文献
929.
930.