地震学报2017，Vol.39Issue(4)：478-494,17.DOI:10.11939/jass.2017.04.004
岩石电阻率图像及各向异性变化的实验研究
Experimental studies on the changes of rock resistivity image and anisotropy
摘要
Abstract
Apparent resistivity data was acquired during the uniaxial compression on two sets of man-made samples.Then we constructed the relative resistivity change (RRC) images corresponding to three radial measuring lines intersecting with the center of a sample surface using electrical resistivity tomography,and plotted the curves of apparent resistivity anisotropy factor λ* and azimuthal angle of anisotropy axis α versus stress and depth.λ* and α represent the rate and direction of crack generation and development respectively.Our results indicate that all RRC images show the same change trend with the change of stress.With the increase of stress,the resistivity-decreased region (RDR) in the RRC images would shrink gradually,while the resistivity-increased region (RIR) would expand gradually.During the process of unloading,with the decrease of stress,the RIR continues to expand,and RDR continues to shrink.The high-resistivity block embedded in a sample has a great influence on the resistivity-increased amplitude at its location and surroundings,but little effect on the trending change of resistivity image.For the samples with originally electrical anisotropy,λ* decreases with the increase of stress;Cracks appeared and developed mainly in the shallower part of a rock sample,while in the deeper part,the rate of crack generation and development is much lower,which can help to explain and understand the changes in resistivity and its anisotropy caused by earthquakes,volcanic activities and large-scale tectonic movements.This method could be a useful complement to the current seismic resistivity observation methods.关键词
岩石电阻率/视电阻率相对变化/电阻率层析成像/视电阻率各向异性Key words
rock resistivity/relative apparent resistivity change/resistivity tomography/apparent resistivity anisotropy分类
天文与地球科学引用本文复制引用
张斌,朱涛,周建国..岩石电阻率图像及各向异性变化的实验研究[J].地震学报,2017,39(4):478-494,17.基金项目
国家自然科学基金(41574083)和中央级公益性科研院所基本科研业务专项(DQJB13B05)共同资助. （41574083）
