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821.
822.
YANG Minghui JIN Zhijun LU Xiuxiang SUN Dongsheng TANG Xuan PENG Gengxin LEI Ganglin 《《地质学报》英文版》2009,83(2)
The eastern Qiulitagh fold and thrust belt (EQFTB) is part of the active Kuqa fold and thrust belts of the northern Tarirn Basin. Seismic reflection profiles have been integrated with surface geologic and drill data to examine the deformation and structure style of the EQFTB, particularly the deformational history of the Dina 2 gas field. Seismic interpretations suggest that Dongqiu 8 is overall a duplex structure developed beneath a passive roof thrust, which generated from a tipline in the Miocene Jidike Formation, and the sole thrust was initiated from the same Jidike Formation evaporite zone that extends westward beneath the Kuqatawu anticline. Dongqiu 5 is a pop-up structure at the western part of the EQFTB, also developed beneath the Jidike Formation evaporite. Very gentle basement dip and steep dipping topographic slope in the EQFTB suggest that the Jidike Formation salt provides effective decoupling. The strong deformation in the EQFTB appears to have developed further south, in an area where evaporite may be lacking. Since the Pliocene, the EQFTB has moved farther south over the evaporite and reached the Yaken area. Restoring a balanced cross-section suggests that the minimum shortening across the EQFTB is more than 7800 m. Assuming that this shortening occurred during the 5.3 Ma timespan, the shortening rate is approximately 1.47 ram/year. 相似文献
823.
桥台在桥梁系统中占据重要位置,桥台的稳定性直接影响到桥梁的抗震性能。在国内外大量震害中发现大量由桥台破坏引起的桥梁损坏,而且这些破坏常常伴随着由于液化引起的地面大变形。为研究液化场地中桥台滑坡机理,采用完全耦合的有效应力分析方法,利用修正的PasterZienkiewicz Mark-Ⅲ模型来模拟砂土在地震荷载作用下的液化特性。研究台顶梁重和液化层位置对桥台位移的影响,并分析夯实作用对砂土液化的影响。结果表明:模拟得出结果与振动台试验结果基本一致,而且简单的夯实不能降低砂土液化的风险。 相似文献
824.
介绍了如何搭建一个系统平台来实现测绘实用程序的共享。所有程序都存储在服务器的数据库上,用户通过网络发布程序、下载程序并通过本地客户端使用程序。 相似文献
825.
多波地震勘探中PSV波的识别技术 总被引:1,自引:0,他引:1
当地震波非垂直入射并在地下存在波阻抗差时,就会产生转换波。由于转换波和入射波之间存在差异,所以可以利用其差异对其进行分离识别。主要介绍了几种PSV波的分离识别方法,并用极化滤波法对波场进行分离识别。 相似文献
826.
黄土剖面古土壤和生物化石14C测年对比 总被引:5,自引:0,他引:5
精确、可靠测定古土壤和生物化石年代是重建环境变化过程、探讨人地关系的关键.研究古土壤中不同组分年代的异同对于分析土壤中碳附存状态和碳储存库十分重要.对甘肃省榆中县境内兴隆山典型黄土剖面采集的动物化石、土壤无机质、土壤有机质3个样品进行常规14C和AMS测年,发现同一地层相同点样品不同组分的测年结果相差悬殊,样品无机质比其有机质年龄(3 682±70)a偏老2 624 a.对其14C测年可靠性对比分析发现,常规14C和AMS对骨骼和牙齿化石测年相差仅为13 a,校正为日历年后几乎相等,认为实验室产生的误差很小,而碳的来源、组成及其"死碳"混入的比例是影响测年结果的主要因素.化石年龄与土壤有机质年龄之间的差别,揭示该剖面可能存在持续时间达千年以上的沉积间断.由于同一层位骨化石、土壤有机质、土壤无机质14C测年结果差异,在进行化石年代确定、考古及古文明研究、生态植被恢复、土壤无机碳存储库研究中,年龄的界定应选择相应的测年数据. 相似文献
827.
基于同量阶迭代法,在保留同阶面的前提下,对林建国等(1998a)得到的二阶Boussinesq类方程进行了求解,得到了与其量阶相对应的取立波解,并春与Euler方程的二阶孤立波解进行了比较,结果显示,本文解比传统Boussinesq方程的孤立波解有明显的改善,扩大了孤立的适用范围。 相似文献
828.
APPLICATION OF DEM GENERATION TECHNOLOGY FROM HIGH RESOLUTION SATELLITE IMAGE IN QUANTITATIVE ACTIVE TECTONICS STUDY: A CASE STUDY OF FAULT SCARPS IN THE SOUTHERN MARGIN OF KUMISHI BASIN 下载免费PDF全文
WANG Si-yu AI Ming WU Chuan-yong LEI Qi-yun ZHANG Hui-ping REN Guang-xue LI Chuan-you REN Zhi-kun 《地震地质》2018,40(5):999-1017
Traditional method to generate Digital Elevation Model (DEM)through topographic map and topographic measurement has weak points such as low efficiency, long operating time and small range. The emergence of DEM-generation technology from high resolution satellite image provides a new method for rapid acquisition of large terrain and geomorphic data, which greatly improves the efficiency of data acquisition. This method costs lower compared with LiDAR (Light Detection and Ranging), has large coverage compared with SfM (Structure from Motion). However, there is still lack of report on whether the accuracy of DEM generated from stereo-imagery satisfies the quantitative research of active tectonics. This research is based on LPS (Leica Photogrammetry Suit)software platform, using Worldview-2 panchromatic stereo-imagery as data source, selecting Kumishi Basin in eastern Tianshan Mountains with little vegetation as study area. We generated 0.5m resolution DEM of 5-km swath along the newly discovered rupture zone at the south of Kumishi Basin, measured the height of fault scarps on different levels of alluvial fans based on the DEM, then compared with the scarp height measured by differential GPS survey in the field to analyze the accuracy of the extracted DEM. The results show that the elevation difference between the topographic profiles derived from the extracted DEM and surveyed by differential GPS ranges from -2.82 to 4.87m. The shape of the fault scarp can be finely depicted and the deviation is 0.30m after elevation correction. The accuracy of measuring the height of fault scarps can reach 0.22m, which meets the need of high-precision quantitative research of active tectonics. It provides great convenience for rapidly obtaining fine geometry, profiles morphology, vertical dislocations of fault and important reference for sites selection for trench excavation, slip rate, and samples. This method has broad prospects in the study of active tectonics. 相似文献
829.
在中国大陆科学钻探工程“科钻一井”的钻井施工中,形成了独具中国特色的新型科学钻探技术体系。详细论述了该新型科学钻探技术体系的具体内容及其在“科钻一井”施工中取得的主要技术指标;简要介绍了目前国内正在或即将实施的科学钻探工程项目情况;结合即将出台的《国务院关于加强地质工作的决定》和2005年已启动的危机矿山接替资源的找矿勘查工作计划,展示了探矿工程广阔的前景。 相似文献
830.
Fluid Inclusions of Calcite and Sources of Ore-forming Fluids in the Huize Zn-Pb-(Ag-Ge) District, Yunnan, China 总被引:1,自引:2,他引:1
HAN Runsheng LIU Congqiang HUANG Zhilong MA Deyun LI Yuan HU Bin MA Gengsheng LEI LiOpen Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou Kunming University of Science Technology Kunming Yunnan Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou 《《地质学报》英文版》2004,78(2):583-591
The Huize Zn-Pb- (Ag-Ge) district is a typical representative of the well-known medium-to large-sized carbonate-hosted Zn-Pb- (Ag-Ge) deposits, occurring in the Sichuan-Yunnan-Guizhou Pb-Zn Ore-forming Zone. Generally, fluid inclusions within calcite, one of the major gangue minerals, are dominated by two kinds of small (1-10 um) inclusions including pure-liquid and liquid. The inclusions exist in concentrated groups along the crystal planes of the calcite. The ore-forming fluids containing Pb and Zn, which belong to the Na+-K+-Ca2+-Cl--F--SO42- type, are characterized by temperatures of 164-221℃, medium salinity in 5-10.8 wt% NaCl, and medium pressure at 410×105 to 661×105 Pa. The contents of Na+-K+ and C1--F-, and ratios of Na+/K+-Cl-/F- in fluid inclusions present good linearity. The ratios of Na+/K+ (4.66-6.71) and Cl-/F- (18.21-31.04) in the fluid inclusions of calcite are relatively high, while those of Na+/K+ (0.29-5.69) and Cl-/F- (5.00-26.0) in the inclusions of sphalerite and pyrite are rela 相似文献