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791.
分析国家重力基准的现状,对国家重力基准的建立和维护提出建议.  相似文献   
792.
Loss assessment and decision-making are essential for earthquake emergency rescues,and for scientific prediction of seismic damage and determination of rescue objectives.In practice,however,there exist some problems,such as basic data not being precise and rich enough and decision making not having systematic and complete criteria.This paper tries to solve these problems using the method of data indexation by constructing an index system for earthquake emergency loss assessment and decision-making.  相似文献   
793.
依舒断裂带北段及邻近地区地震活动性的初步研究   总被引:1,自引:0,他引:1  
利用1970~2007年发生在研究区域(48°00’150°00’N,128°00’--134°00’E)的地震,用测震学方法研究该区内地震活动性,认为b-t曲线变化与地震活动有很强的对应关系。  相似文献   
794.
This study estimates the far field coseismic deformation of China and its surrounding areas caused by the Mw9.0 Tohoku earthquake of Japan using continuous GPS (cGPS) data and final orbits released by International GNSS Service (IGS). Based on these data, we feature the coseismic offsets of several plates affected by the event. Static far field coseismic offsets greater than 2 mm are detected in a wide area of China, which extends as far as about 3,000 km off the epicenter, consisting of that of the 2010 Maule, Chile earthquake. In northeast China, displacements up to 32.7 mm toward southeast are observed; meanwhile, offsets in North China reach about 5–11 mm toward east. Coseismic jumps of about 2–5 mm are measured in South China toward southeast. The southwest extrusion of the Philippine Sea plate is verified by GPS slip vectors, showing that the Philippine Sea plate is decoupled from the Pacific plate by the earthquake. We also infer that the Amurian plate and the Okhotsk plate couple well according to relatively continuous GPS offsets in these plates. Furthermore, the dense far field cGPS offsets due to the Tohoku event hopefully provide opportunities to model the coseismic slip distribution.  相似文献   
795.
地震应急指挥协同技术平台设计研究   总被引:7,自引:7,他引:0  
地震应急指挥协同服务能力是国家地震社会服务能力建设的核心内容,我国的地震应急指挥协同服务能力在研究和建设方面尚处于起步阶段,在未来一段时间将开展地震应急指挥协同技术平台的建设。因此,地震应急指挥协同技术平台的关键构成、设计和实现方式还有许多方面有待进一步研究和探讨。本文根据国家地震社会服务工程的初步设计,对地震应急指挥协同技术平台几个方面的内容进行了初步探讨,在此基础上讨论了其未来进一步发展应进行的工作。  相似文献   
796.
南极地震学研究进展   总被引:3,自引:1,他引:2       下载免费PDF全文
归纳总结了在南极开展地震学研究中的各种主要方法及其研究成果,较全面地介绍了南极地震学研究的现状与进展.首先对南极地震活动性作了简单的介绍,然后分别介绍了利用面波和体波研究地壳上地幔结构的主要成果,最后从地震各向异性的角度归纳介绍了南极大陆部分区域面波方位各向异性及剪切波分裂研究的主要成果.研究表明,南极大陆地震活动性较低、地震强度较小,仅在横贯南极山脉区域、维多利亚地、阿黛利地、威尔克斯地等有较明显的地震活动; 横贯南极山脉将南极大陆分为东南极和西南极两个不同的地质构造区域,东南极地壳和上地幔地震波速度偏高,西南极则偏低;上地幔各向异性较为明显并普遍存在,且西南极各向异性强度稍高于东南极克拉通.   相似文献   
797.
地震滑坡灾害是一种致灾性极高的地震次生灾害,其中的地震触发因素是导致滑坡发生的重要影响因素.可以表征地震影响因素的参数有多种,但它们代表地震动水平的能力有差异,对灾害评估预测结果有很大影响.因此,本文提出利用层次分析法将多种地震动参数联合应用以弥补不同参数间存在的不足和差异.计算实例表明, 参数联合应用所得评估结果与实际破坏情况最为接近,优于参数单独使用所得评估结果,说明该方法是可行的.文中给出的参数联合应用的方法对于其它地震灾害的评估也有很重要的借鉴意义.   相似文献   
798.
From a conventional viewpoint, seismic‐prospecting background noise is usually regarded as the product of a stationary and Gaussian stochastic process. In this paper, we use statistical methods to investigate the properties of the land‐seismic‐prospecting background noise on stationarity, Gaussianity, power spectral density, and spatial correlation. We use and analyse the passive noise records collected by receiver arrays at different typical geological environments (desert, steppe, and mountainous regions). Differences exist in the statistical properties of the background noise from different geological environments, but we still find some common characteristics. It is shown that the background noise is not strictly stationary and has different stationary properties over different timescales. Most of the noise records appear to be a Gaussian process when examined over a period of about 20 s but are found to be non‐Gaussian when examined over shorter periods of about 1 s. The background noise is a kind of colored noise, and its energy mainly concentrates in the low‐frequency bands. We also find that the spatial correlation of the background noise is weak. The results of this paper provide a scientific understanding about the properties of seismic‐prospecting background noise.  相似文献   
799.
应用黑龙江省数字遥测地震台网2002-2006年目录数据,对绥棱采石场附近爆破进行重新定位,对比GPS实测位置,研究该黑龙江省数字地震台网“十五”数据处理软件系统(MSDP 人机交互系统)提供的5种定位程序,初步认为,对于网内浅源地震定位,单纯型法优于其他方法。  相似文献   
800.
Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. In this study, a high resolution (30 m) global land cover dataset (GlobeLand30) produced by Chinese scientists was, for the first time, used in the Beijing Climate Center Climate System Model (BCC_CSM) to assess the influences of land cover dataset on land surface and climate simulations. A two-step strategy was designed to use the GlobeLand30 data in the model. First, the GlobeLand30 data were merged with other satellite remote sensing and climate datasets to regenerate plant functional type (PFT) data fitted for the BCC_CSM. Second, the up-scaling based on an area-weighted approach was used to aggregate the fine-resolution GlobeLand30 land cover type and area percentage with the coarser model grid resolutions globally. The GlobeLand30-based and the BCC_CSM-based land cover data had generally consistent spatial distribution features, but there were some differences between them. The simulation results of the different land cover type dataset change experiments showed that effects of the new PFT data were larger than those of the new glaciers and water bodies (lakes and wetlands). The maximum value was attained when dataset of all land cover types were changed. The positive bias of precipitation in the mid-high latitude of the northern hemisphere and the negative bias in the Amazon, as well as the negative bias of air temperature in part of the southern hemisphere, were reduced when the GlobeLand30-based data were used in the BCC_CSM atmosphere model. The results suggest that the GlobeLand30 data are suitable for use in the BCC_CSM component models and can improve the performance of the land and atmosphere simulations.  相似文献   
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