地震地质 ›› 2023, Vol. 45 ›› Issue (3): 638-651.DOI: 10.3969/j.issn.0253-4967.2023.03.003

• 研究论文 • 上一篇    下一篇

利用微水试验方法研究井-含水层水力参数及其与地震的对应关系

吕芳1,4)(), 穆慧敏1,4), 李艳1,4), 郭文峰1,4), 姚林鹏2,4), 宫静芝3,4)   

  1. 1) 山西省地震局, 太原 030021
    2) 山西省地震局, 运城地震监测中心站, 运城 044400
    3) 山西省地震局, 太原地震监测中心站, 太原 030025
    4) 太原大陆裂谷动力学国家野外科学观测研究站, 太原 030025
  • 收稿日期:2022-11-29 修回日期:2023-01-30 出版日期:2023-06-20 发布日期:2023-07-18
  • 作者简介:

    吕芳, 女, 1982年生, 2008年于太原理工大学获地球探测与信息技术专业硕士学位, 高级工程师, 主要研究方向为地震地下流体, E-mail:

  • 基金资助:
    中国地震局地震科技星火计划项目(XH20012Y); 山西省基础研究计划项目(20210302124049); 2022年度震情跟踪定向工作任务(2022010305); 中国地震局地质研究所国家野外科学观测研究站研究课题(NORSTY2021-02)

USING SLUG TEST METHOD TO STUDY HYDROGEOLOGICAL PARAMETERS OF WELL-AQUIFER AND THE CORRESPONDING RELATIONSHIP WITH EARTHQUAKE

LÜ Fang1,4)(), MU Hui-min1,4), LI Yan1,4), GUO Wen-feng1,4), YAO Lin-peng2,4), GONG Jing-zhi3,4)   

  1. 1) Shanxi Earthquake Agency, Taiyuan 030021, China
    2) Yuncheng Central Seismic Station of Shanxi Earthquake Agency, Yuncheng 044400, China
    3) Taiyuan Central Seismic Station of Shanxi Earthquake Agency, Taiyuan 030025, China
    4) National Scientific Field Observatory of Continental Rift Dynamics in Taiyuan, Taiyuan 030025, China
  • Received:2022-11-29 Revised:2023-01-30 Online:2023-06-20 Published:2023-07-18

摘要:

准确及时地获取井-含水层系统的水力参数, 是当前地震地下水异常识别、 异常核实分析面临的关键技术问题。文中基于山西地区8口地下流体观测井, 利用微水试验方法估算了各井孔的观测含水层导水系数, 对比分析了各井-含水层导水系数及其对井水位同震响应的影响, 得到以下认识: 1)导水系数大的井孔, 同震响应多为震荡型; 2)利用微水试验方法可动态获取井-含水层水力参数, 捕捉含水层介质状态的细微变化, 更准确地解释井水位动态变化; 3)水位秒采样观测仪器的普及使用, 使得利用微水试验方法测定地下流体含水层介质参数时更为方便实用。

关键词: 流体观测井, 微水试验, 井-含水层系统, 导水系数, 同震响应

Abstract:

Hydraulic parameters of aquifers are important parameters for studying the rule of groundwater movement, and also key parameters for regional groundwater resource evaluation, groundwater flow numerical simulation and groundwater quantitative calculation. Aquifer hydraulic parameters also play an important role in the study of groundwater dynamic characteristics and their relationship with earthquakes. Among all kinds of hydrological responses caused by earthquakes, the change in well water level is the most common. Stress accumulation in the process of earthquake preparation, static stress caused by fault dislocation after the earthquake, and dynamic stress caused by seismic wave propagation will lead to the change of crust-media structure at local or regional scales, which will inevitably lead to the change of media characteristics(such as permeability)of the aquifer in the rock mass. As a result, the well water level will change. Therefore, the study of aquifer hydraulic parameters is of great significance to understand the role of groundwater in the process of earthquake preparation and occurrence to understand the hydrological response mechanism related to earthquakes.
China has the largest seismic underground fluid observation network in the world, but most of the observation wells are transformed from geological and petroleum wells, lack complete basic data, and most of the hydraulic parameters of the aquifer are unknown. For underground water level real-time monitoring wells or seismic precursor information observation wells, hydraulic parameters can be obtained by traditional pumping test methods when the well is completed, but it is difficult to implement in order to ensure the continuity of observation data after the well is put into use. The hydraulic parameters of the-well-aquifer system often change with the change in the regional groundwater environment. In order to more accurately interpret the dynamic changes of the observed well water level, we need to obtain the hydraulic parameters of the-well-aquifer system under the current state. As a single well hydraulic test, the slug test has the characteristics of convenient operation, short test time, and low disturbance to aquifer, which can easily and relatively quickly obtain the hydraulic parameters of well-aquifer. With the advent of the digital water level measuring instrument of second sampling rate and its widespread use in the observation of underground fluid, the slug test method is more widely used in the determination of hydraulic parameters of the underground fluid aquifer.
In this paper, the water-level time response data of 8 wells in Shanxi area were obtained by using the Slug test method, and the water conductance coefficient of the observed aquifer was estimated by selecting the corresponding data analysis model according to the attenuation type of water level. The coefficient of transmissivity of each well-aquifer is compared and analyzed by statistics of the co-seismic response of each well and discusses the reliability of the Slug test estimation results and the applicability of the method. The following conclusions are obtained: 1)The co-seismic response of wells with large transmissivity is usually of vibration type. 2)The hydrogeological parameters of the well-aquifer can be obtained dynamically by the Slug test, and the subtle changes of aquifer medium state can be captured to interpret the dynamic changes of well water level more accurately. 3)With the popularization of water level high-frequency sampling observation instruments, the Slug test has been well used in the parameter determination of high permeability medium in underground fluids.
The results show that the slug test method can quickly and accurately obtain the hydraulic parameters of the well-aquifer, capture the change of aquifer medium state in time, interpret the dynamic change of well water level more accurately, and conduct quantitative analysis of the abnormal change of water level.

Key words: fluid observation wells, Slug test, well-aquifer system, coefficient of transmissivity, co-seismic response