【作者】 晏锐；

【导师】 陈颙； 黄辅琼；

【作者基本信息】 中国地震局地震预测研究所 ， 固体地球物理学， 2008， 硕士

【摘要】 地下流体广泛存在于地表以下的地球固体介质中。地下流体指地表以下一切可流动的物质,一般指地壳浅层的水、气、油等以及深层的超临界流体与硅酸盐熔体,它们是地壳物质的重要组成部分,在压力、温度、浓度、密度等梯度作用下运动,具有可流动性。它们与地壳的固体介质发生相互作用表现出十分活跃的物理化学性质。同时地下流体在地壳运动及地震过程中具有独特的作用和表现,对构造活动与地震过程具有灵敏的信息响应。地震地下水位观测通常建立在井-含水层系统的基础上进行观测。井水位变化对地壳微小的应力-应变具有明显的放大作用和十分灵敏的反应。1毫米的水位变化一般可反应含水层10-10量级的体应变。所以,井—含水层系统可以看作是窥视地壳应力活动的天然综合仪器,它可以在一定程度上起到应变仪、蠕变仪和长周期地震仪的作用。研究井水位变化与应力-应变之间的关系,对监测地震可能引起的地壳形变,对研究地震孕育过程中地壳的应力-应变变化,以及探索地震预测等都具有重大意义。地震地下水位观测是以捕捉地震活动信息为目的的浅层地壳流体观测手段。但连续水位观测不仅仅观测到与地震活动有关的信息,而且还掺杂着许多非地震方面的信息,比如大气压力的波动引起井水位的反向变化,大气降水、降雪和其它荷载作用以及抽水、注水都会使井水位发生显著变化。研究地震地下水位动态中存在的各种影响因素,对于识别与提取地震前兆信息及对认识含水层特性都是至关重要的。本文以地球物理学和水文地质学为基础,利用中国大陆地震地下流体现有的观测条件,详细分析了地震地下水位观测的物理基础和观测中存在的几种影响因素以及提取有用信息的方法,讨论了井水位和应力-应变之间的关系,探讨利用地震地下水位观测资料获取含水层介质参数的方法以及介质参数的变化与中强地震活动之间的关系。这对了解含水层特性和探索井水位动态在地震孕育与发生过程中的作用,对地震预测研究具有一定的理论和现实意义。更多还原

【Abstract】 Underground fluids exist extensively among solid earth mediums. Underground fluids are all of the matter that can flow under subsurface. Commonly they are water, air, oil and Supercritical Fluid (SCF) and silicate melt in the deep layer. They are the important composition of crustal matter. They can flow under the grads of pressure, temperature and concentration etc. The physical and chemical properties can be actively behaved when they interact with solid earth mediums. At the same time, the underground fluids have special actions and manifestations among the crustal movement and earthquakes process. They can sensitively response to tectonic activity and earthquake process.Earthquake underground water level observations often set up on the bases of well-aquifer system. The water level changes of well-aquifer system have obvious magnification and very sensitive action to slight stress and strain. The water level changes of 1mm can probably response to 10-10 volume strain. So, the observation of water level changes can look as natural synthesis instrument which can look into crustal stress activities. To some degree, they can act as strain gauge, creep gauge and long period seismometer. Studying the relationship between well water level and stress-strain has great significance to observe crustal deformation probably caused by earthquake, to study the crustal stress-strain activities in the process of earthquake and to explore earthquake prediction investigation.Earthquake underground water level observation is a means in order to get earthquake anomaly information. But not only seismic information but also other aseismic information can also be observed in the continuing water level observation. For example, barometric pressure fluctuations can arouse the reverse changes of well water level. Atmosphere precipitation, snow and other loading action and water pumping and water injection can also arouse well water level obvious changes. So studying all kinds of influence factor of earthquake underground water level observation and knowing of their relationship have great importance to understand aquifer characteristics.This paper is based on geophysics and hydroseismology. The existing observation condition of earthquake underground fluid in China mainland was used. to analyze physical basis and all kinds of influence factor of earthquake underground water level and to study the methods of getting useful information. The relationship between water level and stress-strain was discussed. The methods of obtain medium parameters about aquifer system was explored using earthquake underground water level data. The relationship between the changes of aquifer parameters and medium strong earthquakes was discussed. This study provides preparation for know of aquifer characteristics and exploring the action of well water level changes in the process of earthquake occurring and has certain theoretical and practical significance.更多还原