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931.
932.
933.
杜东菊 《地球科学与环境学报》1989,(3)
近年来,应用断层泥扫描电子显微(SEM)构造来研究断裂的活动性,已引起了国内、外地震地质和工程地质的重视。本文通过对秦皇岛市区几条断裂带断层泥和断层泥中石英颗粒表面SEM构造特征的研究,对断裂带的相对活动时限及活动特征进行了探讨。研究成果与野外宏观调查、现场仪器测试、遥感101系统图象处理结果基本吻合,在微观领域为市区断裂活动性研究提供了依据。这说明该方法在工程地质领域具有重要的实际应用价值。 相似文献
934.
935.
Centrifuge modeling of PGD response of buried pipe 总被引:1,自引:1,他引:0
MichaelO'Rourke VikramGadicherla TarekAbdoun 《地震工程与工程振动(英文版)》2005,4(1):69-73
A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI‘s 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results. 相似文献
936.
Average slip rate,earthquake rupturing segmentation and recurrence behavior on the Litang fault zone,western Sichuan Province,China 总被引:3,自引:0,他引:3
XU Xiwei WEN Xueze YU Guihua ZHENG Rongzhang LUO Haiyuan & ZHENG Bin . Institute of Geology China Earthquake Administration Beijing China . Earthquake Administration of Sichuan Province Chengdu China 《中国科学D辑(英文版)》2005,48(8):1183-1196
The Litang fault zone (LFZ) is an important active fault within the northwestern Sichuan sub-block. To-gether with the Garzê-Yushu, Xianshuihe, and An-ninghe fault zones on its northern, eastern and south-eastern sides, the LFZ constitutes the lateral extrusion tectonic system in the southeastern part of the Qing-hai-Tibetan Plateau[1,2] (Fig. 1). According to instru-mental records, historical recordings and field investi- gation, an earthquake (Ms7.3) occurred on its middle to south se… 相似文献
937.
938.
Co-seismic ground deformation and source parameters of Mani M7.9 earthquake inferred from spaceborne D-InSAR observation data 总被引:4,自引:0,他引:4
SHAN Xinjian MA Jin WANG Changlin LIU Jiahang SONG Xiaoyu & ZHANG Guifang .Institute of Geology Laboratory of Tectonophysics China Seismological Bureau Beijing China .Institute of Remote Sensing Application Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2004,47(6):481-488
In recent ten years, Differential Interferometric Synthetic Aperture Radar (D-InSAR) has become a major technique of space-based geodesy together with GPS, VLBI and SLR. Interferometric Synthetic Aper-ture Radar (InSAR) has many advantages, such as all-weather, all-time, strong stability and dynamic survey property, and no requirements for ground sta-tions. In particular, the surveying results by InSAR can cover a large range of the ground deformation field in succession and has gr… 相似文献
939.
岷山隆起西以岷江断裂为界,东为虎牙断裂。该地区构造活动强烈,地震活动频繁,是重要活动区。岷山隆起是岷江断裂和虎牙断裂由西向东的推覆逆掩运动差异运动导致的。GPS及地质研究表明岷江断裂、虎牙断裂现今仍在活动。岷江断裂为左右旋走滑断裂,运动速度大于2mm/a;虎牙断裂整体速度2.55mm/a,断裂性质为右旋走滑断裂,而震源机制解为左旋走滑断裂。这一结果,可能与GPS观测时段、位置及断裂面结构、几何特征有关。 相似文献
940.
New geomorphic evidence for anticlinal growth driven by blind-thrust faulting along the northern Marche coastal belt (central Italy) 总被引:2,自引:0,他引:2
The Northern Marche coastal belt is characterised by a series of NW-SE trending, NE verging folds forming the easternmost edge of the Apennines thrust front. Several geomorphic features suggest that the folds are still growing and hence that the thrust front is active. The occurrence of several historical and instrumental earthquakes (e.g. 1672, 1690, 1786, 1875, 1916, 1930, 1972, all having Me 5.2) suggests that the thrust faults are also seismogenic.We performed a geomorphological analysis to identify and characterise the faults driving the active folds. Our approach assumes that anomalous drainage patterns and deformed Middle-Late Pleistocene alluvial and coastal terraces are indicators of the vertical component of tectonic strain. We identified, mapped and correlated with sea-level fluctuations a sequence of alluvial and coastal terraces. Longitudinal profiles of six rivers (Conca, Foglia, Metauro, Cesano, Misa, and Esino) show that terraces (1) consistently converge downstream, suggesting that they result from regional uplift that dies out near the coast, and (2) some are slightly warped where they cross anticline axes. We interpreted as coastal terraces several land-surface remnants arranged parallel to the present coastline. Lower remnants clearly top off gently landward-tilted coastal deposits. Reconstructed coastal terraces also seem to be tectonically warped.Our results help characterise the geometry and segmentation of a system that generated the largest earthquakes of the region and suggest the loci of potential seismic gaps. We conclude that the earthquake potential of the densely populated northern Marche coastal belt may be substantially higher than currently estimated. 相似文献