汶川地震断裂带科学钻探3P孔井中注水诱发地震研究

发布时间：2018-04-02 12:11

本文选题：科学钻探　切入点：地震台网　出处：《中国地质大学(北京)》2015年硕士论文

【摘要】：本文论述了科学钻探及其在社会、经济方面的意义。2008年5月12日,在我国四川省发生了震撼世界的汶川特大地震,科技部、国土资源部和中国地震局在汶川特大地震及其余震尚在继续的特殊时期,联合组织快速实施了汶川地震断裂带科学钻探研究项目,该项目计划在龙门山映秀-北川断裂和安县-灌县断裂的上盘布置5口科学钻探。本次注水实验场地选址位于汶川地震断裂带科学钻探项目WFSD-3P孔,该钻孔位于安县-灌县断裂的上盘,这一断裂带属龙门山前山断裂带,实验目的是通过钻孔压水人工诱发地震实验来研究流体对断层行为作用。2012年11月28日至2013年3月9日,我们进行了为期101天的注水诱发地震实验,实验期间,将获得流量、压力、微地震数据、地电数据以及其他气象数据。本次实验借鉴了德国大陆超深钻井注水诱发地震实验的经验,通过控制注入的流量,观察压力的变化,每级注水的流量基本保持不变。实验期间,压力会随着井内注入流量的多少而发生变化。通过布设的地震观测台网,监测到微地震事件的发生。实验通过长期观测以及对数据的分析,获得注水期间每天发生的微地震数、流量以及压力的关系。实验的注水总量达到47520m3,其中,在注水初始4天,注水压力迅速增大,之后连续约1个月时间压力缓慢上升,直到2014年12月28日压力达到最大值。而后,3天时间压力缓慢下降,至2014年1月1日压力突然迅速下降。之后时间压力变化幅度不大,基本趋于稳定,只是在2014年1月16日出现压力低值。2014年2月26日,压力再次发生突然迅速下降。通过分析记录到的824个定位地震事件发现,在上述三次压力下降时间点前后几日内所对应地震事件均有增多趋势。实验结果表明,地震发生破裂位置分布与安县—灌县断裂带断层泥顶底界面有相当密切的联系,分析认为可能是注水实验造成断层再次破裂引起地层漏水所致。结果表明,达到了人工注水诱发地震试验目的。
[Abstract]:This paper discusses scientific drilling and its social and economic significance. On May 12, 2008, the Wenchuan earthquake struck the world in Sichuan Province, and the Ministry of Science and Technology, The Ministry of Land and Resources and the China Seismological Bureau jointly organized and carried out a scientific drilling research project for the Wenchuan earthquake fault zone during the special period when the Wenchuan earthquake and its aftershocks were continuing. The project plans to place five scientific drilling sites on the upper wall of the Yingxiu-Beichuan and Anxian-Guanxian faults in Longmen Mountain. The site of the water injection test site is located in the WFSD-3P hole of the Wenchuan earthquake fracture Zone Scientific drilling Project. The borehole is located on the upper side of the Anxian-Guanxian fault, which belongs to the Qianshan fault zone of Longmen Mountain. The purpose of the experiment is to study the action of fluid on the fault behavior through artificial induced seismic experiments by borehole pressure water, from November 28, 2012 to March 9, 2013. We conducted 101 days of water injection induced seismic experiments, during which flow, pressure, microseismic data were obtained. Geoelectric data and other meteorological data. This experiment draws lessons from the experience of seismic experiments induced by water injection in ultra-deep drilling in the German mainland. By controlling the injected flow rate and observing the change of pressure, the flow rate of each stage of water injection remains basically unchanged. The pressure changes with the amount of water injected into the well. The occurrence of microearthquakes is monitored through a network of seismological observatories. The number of microearthquakes that occur every day during water injection is obtained through long-term observation and analysis of the data. The relationship between flow rate and pressure. The total amount of water injection in the experiment reached 47520m3. In the first four days of water injection, the injection pressure increased rapidly, and then the pressure rose slowly for about one month in a row. Until December 28, 2014, the pressure reached its maximum. After that, the pressure dropped slowly for 3 days, and then dropped suddenly and rapidly on January 1, 2014. After that, the time pressure changed little and tended to be stable. It was only on January 16, 2014, when the pressure was low. On February 26, 2014, the pressure fell again, suddenly and rapidly. The results show that the distribution of earthquake rupture location is closely related to the interface between the top and bottom of the fault gouge in the Anxian-Guanxian fault zone. It is considered that the water injection experiment may be the result of formation leakage caused by fault rupture again. The result shows that the purpose of artificial water injection induced seismic test is achieved.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P315.728

【相似文献】