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81.
介绍了TDP—0844型地震前兆数据综合采集器采用的设计方案及工作原理,及各个功能模块的设计准则,并列出了采集器实现的功能。文章还给出了采集器的部分应用图例,证明该采集器能够满足地震前兆观测需要。 相似文献
82.
2-D crustal velocity structure and vp/vs are obtained by processing and interpretation of S-wave data from Maqen-Jingbian deep seismic sounding(DSS)profile.The result shows that there exist obvious differences in 2-D S-wave velocity structure and vp/vs ratio structure along the profile.The S-wave velocities are low and vp/vs ration is high for the westem section of the profile and Haiyuan region,while they are normal for the middle and eastern sections.The changes in lithologic characters of two major anomalous zones are discussed according to lateral variation of S-wave velocity structure and vp/vs ratio structure.It is concluded that the development and occurrence of the Haiyuan strong earthquake is not only related to tectonic activities,but also to lithologic characters of the region. 相似文献
83.
A laboratory study was conducted to examine oil biodegradation in the presence of a fouling organism community. It is shown that the majority of fouling species exhibit relatively weak tolerance to oil. Oil degradation in seawater is shown to proceed quicker and more completely in the presence of the fouling organism community than it does without such organisms. The population of specific bacterial groups is shown first to grow and next decrease as a result of accumulation in water of toxic products of their vital activity. Oil biodegradation is found to cause substantial changes in the water hydrochemical characteristics in experimental vessels. 相似文献
84.
The Jiaocbang arcuate structure is one of the numerous arcuate structural belts in Sichuan. The present paper gives a further argument about the characteristics of that arcuate structure and the new activity of the Songpinggou fault and affirms that the Songpinggou fault is an active fault in the Holocene epoch. The Diexi M7.5 earthquake took place in 1933 on the west wing of that arcuate structure, near the apex of the arc. Many authors have given quite different opinions about the genetic structure of that earthquake. The authors have made on-the-spot investigations time and again over recent years. Besides this, the authors have also further studied the shape of intensity contour lines, the distribution characteristics of ground surface seismic hazards, the left-lateral dislocation of buildings along the Songpinggou fault, the NWtrending ground fissures that developed on the ground surface after earthquake, and so on. On this basis, it is still considered that the seismogenic fault of the 1933 Diexi M7.5 earthquake was the Songpinggou fault on the west wing of the Jiaochang arcuate structure. 相似文献
85.
陕西省地下水水质监测发展探析 总被引:1,自引:0,他引:1
本文针对陕西省地下水水质监测控制范围局限于农灌区,监测项目单一的现状,通过分析研究,提出水质监测的发展思路,剖析实现新思路的相关条件。 相似文献
86.
Comprehensive lithogenetic analysis of the Nyurol paleobasin revealed a large shoal area surrounded by basins. The shoal area is composed of organogenic buildups covered by sediments of isolated and inner lagoons. The organogenic buildups are divided into two types: Stromatopora bioherms and mud-mounds. Regularities of the distribution of organogenic buildups are considered. 相似文献
87.
A. P. Geptner Yu. I. Pikovskii L. T. Protasevich T. A. Alekseeva M. E. Ramenskaya 《Lithology and Mineral Resources》2003,38(6):509-521
Relationships of mineralized microbiota with the content of polycyclic aromatic hydrocarbons in hydrothermal systems are considered. It has been established that the mineralized microbiota can serve as an indicator of hydrothermal hydrocarbon flows in present-day and ancient deposits. 相似文献
88.
89.
丽江大研镇震灾分布和地脉动测量结果之间的相关性 总被引:4,自引:2,他引:4
丽江7.0级地震后,大研镇被毁建筑物的地理分布呈显4条条带,伤亡人员的地理分布和上述条带重合。91个短周期地脉动测点的观测资料表明,分布在上述条带内的大多数测点,其卓越周期大于0.3S;条带外的测点,其卓越周期一般在0.1S左右。作认为卓越周期和烈度异常之间良好的相关性,是因为地脉动卓越周期和地方震的频谱之间存在良好的相关性。 相似文献
90.
南极中山站数字式电离层测高仪的初步观测结果 总被引:5,自引:0,他引:5
本文介绍数字式电离层测高仪DPS-4的原理和特点,在中山站的安装和调试,从扫频电离图所得到的初步结果表明,中山站冬季电离层F层存在明显的磁中午现象,而电离层Es层与极光粒子沉降有很大关系;漂移测量的结果表明,电离层漂移主要是水平方向的运动,并且具有大体一致的日变化模式,显示出在极区存在逆阳对流。 相似文献