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991.
Earthquakes result from continuous geodynamic processes. A topic of significant interest for the scientific community is to elaborate on the phenomena governing the faulting and fracturing of crustal rocks. Therefore, in this study, uniaxial compressive shear failure experiments were conducted on Fangshan marble rock samples with a prefabricated slot to simulate thrust faulting. The center of each marble plate (105 mm × 80 mm × 5 mm) was engraved with a 30-mm long double-sided nonpenetrating slot (depth: 2 mm, width: 0.5 mm). The deformation and destruction processes of the rock surface were recorded using a high-speed camera. The digital image correlation method was used to calculate the displacement and strain distribution and variation at different loading stages. The accumulative and incremental displacement fields u and v , strain field ex and ey, and shear strain exy were analyzed. When the loading level reached its ultimate value, the strain field was concentrated around the prefabricated slot. The concentration reached a maximum at the ends of the prefabricated slot. The magnitude of shear strain reached 0.1. This experiment contributes to our understanding of the dynamic process of active faulting. 相似文献
992.
现有地震灾害评估系统多以设定地震的方式进行震害评估,无法满足地震灾害风险评估中按照不同烈度对整个行政区域进行地震灾害评估的业务需求,本文以现有计算模型为框架、以ArcEngine 为GIS开发平台、采用C/S结构进行基于居民地的不同烈度下地震灾害评估系统设计。系统以居民地为评估单元,根据选择的评估区域,按照Ⅵ度、Ⅶ度、Ⅷ度、Ⅸ度、大于等于Ⅹ度5个级别分别进行地震灾害建筑物损坏情况和人员伤亡评估,结果可为各级政府及相关部门进行区域地震风险评估、地震灾害预评估提供技术支持。 相似文献
993.
An accessible strong-motion dataset (PGA,PGV, and site vS30) of 2022 MS6.8 Luding,China Earthquake 下载免费PDF全文
Jian Zhou Nan Xi Chuanchuan Kang Li Li Kun Chen Xin Tian Chao Wang Jifeng Tian 《地震科学(英文版)》2023,36(4):309-315
A MS6.8 earthquake occurred on 5th September 2022 in Luding county, Sichuan, China, at 12: 52 Beijing Time(4:52 UTC). We complied a dataset of PGA, PGV, and site vS30 of 73 accelerometers and 791 Micro-Electro-Mechanical System(MEMS)sensors within 300 km of the epicenter. The inferred vS30 of 820 recording sites were validated. The study results show that:(1)The maximum horizontal PGA and PGV reaches 634.1 Gal and 71.1 cm/s respectively.(2) Over 80% of records ar... 相似文献
994.
995.
Recognition of natural deformation during the excavation of ancient remains and tombs is important for tracing or enriching historic and prehistoric deformation records. Recently, the earthquake agencies,in cooperation with the cultural relics and archaeological institutions, conducted a special excavation investigation to the Gaixia remains archaeological scene in Guzhen,Anhui Province. Faults and fissures were discovered there, which,as demonstrated by the preliminary study,are the traces of two stratum d... 相似文献
996.
The temporal variability of 210Po and 210Pb was examined in the overlying water of the Zhubi Coral Reef flat to detect nutrient-like behavior of 210Po. Different mechanisms influencing their geochemical behaviors were observed. Excess 210Po relative to 210Pb revealed an additional input of 210Po other than in situ production from 210Pb. The 210Po input comes from the reef flat sediment through diffusion. The diffusion contributes 62% of the total 210Po. This diffusion of 210Po directly highlights its nutrient-like behavior. No input, but the slight removal, of 210Pb was observed. Fractionation factors indicate that particulate matter prefers to adsorb 210Po rather than 210Pb. In combination with particulate composition, 210Po diffusion was closely related to organic matter. These results reveal that 210Po might be a potential tracer for quantifying nutrient recycling in the Coral Reef system. 相似文献
997.
Optimizing layout of pumping well in irrigation district for groundwater sustainable use in northwest China 总被引:1,自引:0,他引:1 下载免费PDF全文
Optimizing layout of pumping well plays a vital role in curbing the groundwater level decline. A novel optimization model is presented in this study. First, the optimal well number is obtained by taking into account factors of local economy and environment based on nonlinear programming model. Then, the well spatial layout assessment model is attained based on information entropy weight and technique for order preference by similarity to ideal solution (TOPSIS). After that, the relative closeness to positive ideal solution of alternative (ci) on the rationality of well spatial layout in cultivated land is calculated, and a set of alternatives are ranked according to the descending order of ci. Finally, the well optimization layout is obtained by combining the optimal well number with well spatial layout assessment result based on the GIS data of pumping wells. As a case study, this method was applied in Yongchang Irrigation District of Shiyang River Basin, the arid region of northwest China. Results show that under the conditions of sustainable use of water resources, the irrigation district needed 724 wells for irrigation, with a decrease of 31.0% when compared with the existing number of wells. The wells with low flow rate and operating efficiency distributed in high density where groundwater is over‐exploitation were recommended to be closed. This well optimization layout method is expected to play a significant role in helping make plans for exploiting groundwater at more sustainable level, curbing the groundwater level decline trend, and improving the local ecological environment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
998.
Flat and steep subduction are end-member modes of oceanic subduction zones with flat subduction occurring at about 10% of the modern convergent margins and mainly around the Pacific. Continental (margin) subduction normally follows oceanic subduction with the remarkable event of formation and exhumation of high- to ultrahigh-pressure (HP–UHP) metamorphic rocks in the continental subduction/collision zones. We used 2D thermo-mechanical numerical models to study the contrasting subduction/collision styles as well as the formation and exhumation of HP–UHP rocks in both flat and steep subduction modes. In the reference flat subduction model, the two plates are highly coupled and only HP metamorphic rocks are formed and exhumed. In contrast, the two plates are less coupled and UHP rocks are formed and exhumed in the reference steep subduction model. In addition, faster convergence of the reference flat subduction model produces extrusion of UHP rocks. Slower convergence of the reference flat subduction model results in two-sided subduction/collision. The higher/lower convergence velocities of the reference steep subduction model can both produce exhumation of UHP rocks. A comparison of our numerical results with the Himalayan collisional belt suggests two possible scenarios: (1) A spatially differential subduction/collision model, which indicates that steep subduction dominates in the western Himalaya, while flat subduction dominates in the extensional central Himalaya; and (2) A temporally differential subduction/collision model, which favors earlier continental plate (flat) subduction with high convergence velocity in the western Himalaya, and later (flat) subduction with relatively low convergence velocity in the central Himalaya. 相似文献
999.
利用安徽省地磁台站2007-2009年数字化观测资料,应用地磁转换函数方法,对华东地区ML4.0以上地震进行对应关系研究,发现不同台站、不同周期的转换函数参量与安徽及邻近地区地震存在一定的对应关系,为今后数据研究提供参考. 相似文献
1000.
陕西地震监测台网震后恢复重建项目实施过程中,通过优化台网布局和增加台网密度,新建GNSS连续观测系统,提高了地震监测能力;采用的通讯网络新架构以及OSPF路由协议,不仅提升了监测网络通讯系统的可靠性,而且取得降低通讯费用的显著成效. 相似文献