摘要
微动探测技术通过提取微动信号中面波频散曲线求取地下介质的横波速度结构,根据横波在不同深度地层中的速度变化,进行介质分层和构造识别。近年来,该技术凭借其绿色环保、抗干扰、勘探深度范围大的优势在资源勘探和工程勘探中崭露头角,而对于微动中频率-波数法的研究由于早前数据采集质量和数据处理能力的限制而受到制约,导致该方法良好的实际应用能力被低估。本文结合微动勘探实例介绍微动高分辨率频率-波数谱法的勘探方法,说明该方法的有效性和先进性。该实例中,使用微动探测技术在一处传统电法无明显异常、无法确定热储位置的区域使用三重圆形台阵布设一条7点测线,准确定位热储,采用高分辨率频率-波数谱法处理数据,微动剖面上视S波低速异常明显,边界清晰,以此为依据定位的热储成功打出热水,证实了该方法的有效性和可靠性;显示了此方法对异常敏感、分辨率高的优势。该方法可针对不同勘探条件灵活设计相应的观测台阵系统,操作简便,非常适合生产单位在城镇等干扰大、不可破坏的环境中开展工程、资源和环境勘探。
The microtremor computes S-wave velocity in underground media by extracting surface wave dispersion curves from the microtremor signal.According to the S-wave velocity change in different depth strata,the medium stratification and structure identification could be carried out.With advantages of environmental protection,anti-interference and great exploration depth,this technology has emerged in resource exploration and engineering exploration in recent years.However,the research on microtremor frequency-wavenumber method is restricted by the limitation of previous data acquisition quality and data processing ability,which leads to the underestimation of its good practical application ability.This study introduces microtremor high-resolution frequency-wavenumber spectrum method with a microtremor exploration case to prove its effectiveness and advancement.In that case,microtremor detection method sets up a line of 7 points on a triple circular array and accurately locates the thermal reservoir in an area where traditional electrical method could not do abnormal detection and locate the thermal reservoir.This method uses high-resolution frequency-wavenumber spectrum method to process data.On the microtremor profile,the S-wave velocity is evidently low and the margin is clear.Based on the result,hot water can be successfully obtained in the predicted location of thermal reservoir,which proves the effectiveness and reliability of this method.It proves sensitivity to anomalies and high resolution of this method.This method allows flexible design of observation array system according to different exploration conditions,and is easy to operate.Therefore,microtremor detection method is very suitable for production units to carry out engineering,resource and environmental exploration in the environment with strong interference and indestructible environment such as cities and towns.
作者
刘杨
盛勇
贾慧涛
Liu Yang;Sheng Yong;Jia Huitao(Institute of Geophysical and Geochemical Survey Technology of Anhui Province, Hefei Anhui 230022, China)
出处
《工程地球物理学报》
2021年第1期35-43,共9页
Chinese Journal of Engineering Geophysics
基金
安徽省国土资源科技项目(编号:2016-K-6)。
关键词
微动探测
高分辨率频率-波数谱法
电法勘探
地热资源勘探
microtremor detection
high-resolution frequency-wavenumber spectrum method
electrical prospecting
geothermal resources exploration
