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81.
矿山地震研究述评   总被引:9,自引:2,他引:9  
就采矿引起的诱发地震活动,即矿山地震的国际研究动态进行评述.重点介绍矿山地震的命名、早期观测与研究、几个主要矿震国家的情况、矿震的分类、矿震的震源机制、矿震震源参数与定标率等问题.还就利用矿山作为天然地震的预报实验场和作为地震技术的推广市场问题进行探讨.  相似文献   
82.
新疆盐湖卤水水化学特征研究   总被引:4,自引:3,他引:4  
要为深入研究新疆盐湖形成演化规律及成盐环境,根据我所历年盐湖科学考察研究结果,对该区盐湖卤水的分布及其化学组成、盐湖卤水的矿化特征和卤水水理性质及水化学类型分类等进行了研究,并通过与我国其它盐湖区盐湖水化学特征的对比分析,确认本区现代盐湖水化学成因类型具有陆相再溶盐成因特征,从而显示了该区盐湖形成演化的独特水文地球化学特点。  相似文献   
83.
84.
杨章 《内陆地震》1990,4(2):126-133
根据新疆及苏联天山地区的地震目录和古地震研究成果,将整个天山地区的地震韵律划分为地震世、地震亚世、地震期、地震幕、地震阶五级,探讨了各级韵律的特征。估计了我国天山地区未来地震活动趋势。  相似文献   
85.
Tilt and strainmeter data collected in the Friuli seismic area between 1977 and 1985 have been analyzed to study the stress-strain field and/or the elastic parameter variations in the area after the strong 1976 seismic event.We concentrated on three different frequency bands, respectively linked with the tidal waves, the seasonal effect and the secular one. The results from the first two bands point at an increase of the local rigidity modulus.Relevant stresses induced by the seasonal groundwater level variations have been found, thus supporting the hypothesis that they can act as triggering effects. The secular trend reveals significant tectonic stress modifications. It appears that the post-seismic tectonic stresses faded during 1981–1983, and were followed by a new loading phase.On leave from the Institute of Geodesy and Geophysics of the Chinese Academy of Sciences. Ph. D. student at the Institute of Geodesy and Geophysics, Trieste University.  相似文献   
86.
Recent improvements in the seismological networks on the Ibero-Maghrebian region have permitted estimation of hypocentral location and focal mechanisms for earthquakes which occurred at South Spain, Alboran Sea and northern Morocco of deep and intermediate depth, with magnitudes between 3.5 and 4.5. Intermediate depth shocks, range from 60 to 100 km, with greater concentration located between Granada and Málaga. Fault-plane solutions of 5 intermediate shocks have been determined; they present a vertical plane in NE-SW or E-W direction. Seismic moments of about 1015 Nm and dimensions of about 1 km have been determined from digital records of Spanish stations.P-wave forms are complex. This may be explained by the crustal structure near the station, discontinuities in the upper mantle and inhomogeneities near the source. Deep activity at about 650 km has only 3 shocks since 1954 (1954, 1973, 1990). Shocks are located at a very small region. Fault-plane solutions show a consistent direction of the pressure axis dipping 45° in E direction. For the 1990 shock seismic moment is 1016 Nm and dimensions 2.6 km. TheP-waves are of simpler form with a single pulse. The intermediate and deep activities are not connected and no activity has been detected between 100 and 650 km. The intermediate shocks may be explained in terms of a recent subduction from Africa under Iberia in SE direction. The very deep activity must be related to a sunk detached block of lithospheric material still sufficiently cold and rigid to generate earthquakes.  相似文献   
87.
陈国顺 《华南地震》1991,11(2):40-46
本文以滑波理论为依据,总结了山西地震带的两种不同特点的滑坡。即:振荡式滑坡及触发式滑坡。虽然两种滑坡都可分为变形、解体、滑动、毁灭等四个阶段,但其动力不同。振荡式滑波的滑动面倾角小,因而滑力来源于强震振动,而触发式滑坡的滑动面倾角大,因而滑力来自滑体本身静荷载。对两种滑坡的研究对预防及减轻强震带来的次生灾害有重要的意义。  相似文献   
88.
The method of coda waves was applied to two different sets of data for the evaluation of the relative site response.The first set of data consists of low magnitude earthquakes with closely spaced locations, recorded at a small aperture array of velocimeters located in the Abruzzo region, central Italy. The second set of data is composed of events with epicentral distance ranging from 20 to 300 km, recorded at a seismological network with an aperture of about 100 km located in the Puglia region, southern Italy.Results show that the coda wave method furnishes stable estimates of the site effect. An amplification, relative to an arbitrary site, of a factor of about 2 occurs in the 1.7–6 Hz frequency band for two stations of the Abruzzo network, while an amplification factor of about 0.5 occurs in the whole frequency band (1–24 Hz) for one of the stations of the Puglia network. This station is located in an area which is correlated with a low macroseismic intensity anomaly.  相似文献   
89.
Fault-weakening effect of reservoir temperature of hot spring and its influence on seismic activities(林元武)Fault-weakeningeffe...  相似文献   
90.
TheabnormalmantleanddeeptectonicprocessinthesouthernregionofNorthChinaPlainShi-YuGAO(高世玉),Hong-XiangHU(胡鸿翔)andShanDING(丁山)(In...  相似文献   
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