Analysis of velocity in Jinfusi overthrust nappe of Yin'er sag of Jiuquan basin and study on buried structural feature
Pan Liang-yun1,2, Zhang Hong-wei2, Sun Xue-dong2, Zhao Jian-ru2, Liu Wen-li2, Duan Xin-hong2, Yan Qun2
1. College of Geosciences, China University of Geosciences, Wuhan City, Hubei Province, 430074,China;
2. GRI, BGP, Zhuozhou City, Hebei Province, 072751, China
Abstract:Overburden high-velocity granite nappe in Jinfusi thrust nappe zone and underlying Neogene high-velocity layer in frontal margin of nappe developed in eastern part of piedmont thrust belt of southern margin of Jiuquan basin, which is velocity-overturned character, leading the buried structural feature of autochthone in footwall, which is composed of Cenozoic and Lower Cretaceous, to appear larger difference in time and depth domains. Using 3-D seismic data and drilling as well as logging data in northern part of Jinfusi overthrust nappe zone, the paper analyzed the changing law of 3-D regional velocity and spatial distribution of underlying Neogene high-velocity layer in northern margin of Jinfusi overthrust nappe zone; according to the feature of structure and velocity in Jinfusi overthrust nappe zone, we implemented continuation of 3-D regional velocity changing tendency southward and created velocity field of Jinfusi overthrust nappe zone by blocks-partitioned layer-controlling method; the study of Jinfusi buried structural feature is carried out by velocity-varying mapping on the basis of average velocity field created by layer-controlling method and structural model interval velocity infilling method and suggestion of next exploration in the region is further put forward.
潘良云, 张宏伟, 孙学栋, 赵建儒, 刘文利, 段新红, 闫群. 酒泉盆地营尔凹陷金佛寺逆冲推覆带速度分析及掩伏构造形态研究[J]. 石油地球物理勘探, 2008, 43(4): 467-472.
Pan Liang-yun, Zhang Hong-wei, Sun Xue-dong, Zhao Jian-ru, Liu Wen-li, Duan Xin-hong, Yan Qun. Analysis of velocity in Jinfusi overthrust nappe of Yin'er sag of Jiuquan basin and study on buried structural feature. OGP, 2008, 43(4): 467-472.