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111.
以多源异构地震灾情数据为研究对象,针对震后灾情获取缓慢且碎片化、公众涉灾信息数据异构、多维、数据格式差异大、部分数据维度缺失导致的数据无法得到综合利用、决策支持不到位等问题,基于相关灾害信息标准化管理,提出多源异构地震数据的一体化编码和接口技术规范。根据此规范,设计实现了灾情数据的一体化编码管理以及基于开放式接口规范的灾情数据接入,从而实现了灾情数据入库、管理、实时发布的全周期一体化管理。同时,给出了多源异构应急信息大数据资源的统一表达模型,为震后应急管理提供了技术保障,提升了灾情数据管理效率。 相似文献
112.
113.
迁安紫苏花岗岩的~(40)Ar/~(39)Ar年龄谱 总被引:1,自引:1,他引:1
对采自河北省迁安县水厂地区的紫苏花岗岩中的黑云母和紫苏辉石进行了~(40)Ar/~(39)Ar年龄测定,分别给出了18.7亿年和19.6亿年的~(40)Ar保存年龄。这两种矿物的年龄谱的视年龄的梯度变化表明,紫苏花岗岩形成后是缓慢冷却的。3.9亿年左右的一次热事件,造成了放射成因~(40)Ar的丢失。根据热历史和封闭温度的研究,从27亿年(侵入到该区紫花岗岩中的花岗闪长岩的锆石U-Pb年龄)到19.6亿年,紫苏花岗岩岩体的抬升速率为6.5m/Ma,但从19.6亿年到18.7亿年,其抬升速率高达111m/Ma,具有明显的构造抬升作用。 相似文献
114.
摘要本文论述了河台金矿区断层岩的类型及其地质和地球化学特征,探讨了糜棱岩带与金矿化的关系,指出剪切应变强度和石英动态重结晶发育程度与金矿化强度密切相关. 相似文献
115.
The properties of rock resitivity were studied under pressure, particularly with “stress reversal”, a procedure in which the
pressure applied was increased and decreased.
It was observed that, 1) With pressure increasing, the main feature of resistivity change was increase-steady-decrease for
high-saturation rock samples (saturation 70–100%). But the main feature for low-saturation samples was different. 2) In 10
out of 11 cases of “stress reversal” for high-saturation samples the resistivity droped (about 2%). Such drop could explain
the anomalies in geoelectricity terms, which are commonly observed before earthquakes in China. 3) It was also observed shortly
before rock failure that, a) the resistivity drops more dramatically (about 20%) during “stress reversal” period, which is
much more than ordinary drops. b) these drops occurred not only during stress decrease but also during stress increase. c)
Resistivity exhibits anisotropy: the resistivity along different directions may differ by 10%. These three features may indicate
that the rock is nearing failure, while ordinary resistivity drops are only connected with “stress reversal” and may not mean
the imminence of rock failure. 4) Resistivity increase was observed during the “stress reversal” period for low-saturation
rock samples.
The results mentioned above were explained with the effect of water flowing in and out of the cracks of rock. The temporary
factors which yield a reduction of the maximum main stress, may enhence the possibility of earthquake occurrence. 相似文献
116.
In this paper, 183 chemical analyses of clinopyroxenes are collected from mantle-derived inclusions inCenozoic basalts of eastern China. Through synthetic studies of the relevant data, their mineral chemistry andgeological significance are discussed. Based on the composition fo clinopyroxenes the authors conclude that theCenozoic upper mantle in eastern China is of the continental, primitive, metasomatic and high-temperaturetypes and is related to rift structural environment and variation in composition of basalts. The geobarometry ofclinopyroxenes indicates that Cenozoic basalts of eastern China are derived from the asthenosphere and thatthe average depth of faults progressively increases from south to north and from east to west. 相似文献
117.
国家气象中心数值预报业务的进展 总被引:1,自引:0,他引:1
在最近的15年中,国家气象中心的数值预报业务高速度发展,预报模式从北半球模式发展为全球谱模式,并配套建立了资料同化系统和用于降水预报的有限区预报模式,暴雨和台风预报模式正在研制中。目前数值预报时效已延至7天,T6393丙上时的预报水平已优于的数值预报产品的应用技术在不断改进,最高(低)气温下两天MOS预报精度已接近预报员制作的综合预报结果。 相似文献
118.
The System Analysis and Reliability Evaluation of Rock Slopes 总被引:1,自引:0,他引:1
Luo Guoyu Yan ChanghongDepartment of Earth Sciences Nanjing University Nanjing Jiangsu Fei Zhenbi 《《地质学报》英文版》1994,68(4)
The principal of preferred plane analysis is a new research view and model of rock slope engineering geology. It advocates that the rock slope stability, boundary conditions and failure model are controlled by preferred planes. Therefore, the problem of slope stability evaluation can be converted into the search for preferred planes and determination of preferred separating bodies. The organic combination of the deterministic model and the indeterministic model can be realized by applying the systems engineering principle and the research model and method of reliability analysis in the quantitative evaluation and prediction of rock slope stability. Finally, the paper presents the case studies of slopes of the Yangtze Gorge Project and the Ma'anshan openpit mine. 相似文献
119.
120.
During late February to mid-March, 1991, when mature N. japonica swarmed in the sea surface off Jimo County, Qingdao, seawater containing numerous early embryos was pumped into a nearby 2.7 ha. muddy-sand shrimp pond, where the embryos continued to develop. 800000 Penaeus chinensis seedlings were introduced into the pond on May 30, 1991. Monthly benthic samplings were carried out to determine the population dynamics and production of N. japonica in this atypical environ -ment.The density of N. japonica varied from 0 to 20400 ind./m2. The predation of P. chinensis was considered to be responsible for the mass mortality of N. japonica in June through July, when the worms were 2.2-3.3cm in length and lived in the top 2-4cm sediment. From August to September of 1991, the hottest period in the site, there was no substantial mortality of N. japonica as reported in earlier literature. This was explained by the deeper burrowing of the' worms that protected them from predation by shrimps.Monthly biomass ranged f 相似文献