煤复电阻率各向异性及其频率响应特征研究

摘要

为了实现煤岩物质组成和结构的高效电法勘探,基于岩石频率域激电效应,采用复电阻率法测试对四种不同变质程度的原生结构煤在不同方向上的复电阻率模值频率响应特征进行了研究.研究结果表明:随着频率不断增加,不同变质程度煤复电阻率模值在走向、倾向、垂向上均依次呈递减趋势;低频阶段复电阻率模值呈现明显各向异性;高频阶段复电阻率模在水平向和垂向呈各向异性,走向和倾向呈各向同性,造成这样的原因与煤中可极化电介质极化的时间长短有关.%In order to realize the high-efficient electrical exploring for the material composition and structure of coal and rock,based on IP effects in frequency domain of rock,by using the method of complex resistivity,frequency response characteristics of complex resistivity for four coal samples with different metamorphic degree were studied in different directions.The experimental results show that complex resistivity of all coal show monotone decrease in vertical direction,trend direction and inclination direction with the increase of frequency.The complex resistivity values are obviously different in low frequency.The coal seam complex resistivity values between trend and inclination performs isotropy and performs anisotropy between horizontal and vertical directions in high frequency.The reason for all this is related to the polarization time for polarizable dielectric in coal.