[关键词]
[摘要]
通过对我国地震地热台网273口观测井的水温数据进行梳理,发现汶川地震前有10口井记录到客观的异常现象;而这些井的异常信息的持续时间、幅度、空间分布极其复杂,决定了利用这些异常信息进行汶川地震三要素的准确预测还不太现实,但也发现一些有一定科学价值的认识:空间上井震距1000km范围内集中了大部分异常点;异常幅度集中在千分之几到百分之几度;时间上异常具有短临性质,呈现出井震距越大持续时间越短、井震距越小持续时间越长的规律;自流井记录到的异常概率远高于静水位井,不过干井也可以记录到异常信息。通过数据梳理与分析,提出了水温异常取决于井-含水层结构以及观测井所处的水系单元位置这一认识。
[Key word]
[Abstract]
There are 10 reliable precursor anomalies prior to the Wenchuan earthquake were found in Chinese Earthquake Geothermal Network(CEGN)after checking the groundwater temperature data in 273 observed wells. The duration,amplitude and spatial distribution of these abnormities have obviously individuality,which causes that it is difficult to make an accurately prediction of three elements of the Wenchuan earthquake. However,some interesting scientific discoveries have been found,the 10 wells with abnormities are concentrated in the 1000km around the epicenter,the amplitude of these abnormities in several thousandths to several hundredths of degree,and the duration has short-term nature. In addition,we find the rule of duration that the longer distance between the epicenter to the well,the shorter the duration and vice versus. The probability in recording abnormities of artesian wells is much higher than the hydrostatic wells,but the dry wells also can record the abnormal information. Based on these analyses,we get the conclusion that the anomaly of water temperature depends on the well-aquifer system structure and the observed well location in water-unit.
[中图分类号]
P315
[基金项目]
国家自然科学基金(41772256)、中国地震局地壳应力研究所基本科研业务专项(ZDJ2017-25)共同资助