| 井间电磁法综述 |
| |
| 引用本文： | 刘四新,倪建福.井间电磁法综述[J].地球物理学进展,2020(1):153-165. |
| |
| 作者姓名： | 刘四新 倪建福 |
| |
| 作者单位： | 吉林大学地球探测科学与技术学院 |
| |
| 基金项目： | 国家自然科学基金(41874136,41574109,41504085)资助. |
| |
| 摘 要： | 地面电磁法在实际工作中在很大程度上受到了探测深度和分辨率的限制.为了克服这些缺点,出现了井间电磁法.井间电磁法指的是在两个(或多个)钻孔中分别发射或接收电磁波信号,利用电磁波信号进行成像并探测井间物理性质的地球物理方法.由于发射机和接收机可以分别放置在很深钻孔中,其具有大透距、大探测深度的特点,因而广泛应用于工程环境物探、矿产勘查、石油勘探等中.针对不同的应用,产生了各具特点的一些特殊方法,包括井间无线电波成像、跨孔雷达、井间电磁成像.井间无线电波成像仪目前只测量电场强度数据,工作频率低,一般是单频的电磁波,频率范围通常在1 kHz至10 MHz.由于缺少走时数据修正射线路径,井间无线电波成像主要是进行基于直射线追踪的衰减层析成像.井间无线电波成像既可用于工程与环境地球物理也可用于找矿.跨孔雷达是钻孔雷达的一种探测方式,用高频电磁脉冲探测两个井孔间介电常数和电导率的变化.跨孔雷达层析成像也叫地质雷达CT,既可进行走时成像,还可进行衰减成像.一般来说,地质雷达CT的电磁波工作频率较高,中心频率通常在10 MHz和1 GHz之间,因此在分辨率指标上占有优势,跨孔雷达主要用于工程与环境地球物理.井间电磁成像采用更低的频率,测量复电磁信号,适合油气储集层监测,是一种地球物理前沿技术.经过在多个试验区初步试验表明,井间电磁成像是油藏研究的有效手段,可用于分析剩余油分布,寻找油气富集区,进而达到提高钻探高效井成功率和提高采收率的目的.本文详细介绍对比了这三种方法在理论和实践中的一些特点,并对未来的发展进行了展望.
|
| 关 键 词： | 井间电磁法 井间无线电波成像 跨孔雷达 井间电磁成像 |
Review for cross-hole electromagnetic method |
| |
| LIU Si-xin,NI Jian-fu.Review for cross-hole electromagnetic method[J].Progress in Geophysics,2020(1):153-165. |
| |
| Authors: | LIU Si-xin NI Jian-fu |
| |
| Institution: | (College of Geo-exploration Science and Technology,Jilin University,Changchun 130026,China) |
| |
| Abstract: | The ground electromagnetic method is largely limited by the depth of detection and resolution in practical work.In order to overcome these shortcomings,the cross-hole electromagnetic method has emerged.The cross-hole electromagnetic method refers to a geophysical method of transmitting or receiving electromagnetic wave signals in two(or more)boreholes,imaging using electromagnetic wave signals,and detecting physical properties between holes.Since the transmitter and the receiver can be placed in deep boreholes respectively,which have the characteristics of large penetration and large depth of detection,they are widely used in engineering environment geophysical exploration,mineral exploration,petroleum exploration and the like.For different applications,special methods have been created,including cross-hole radio imaging method,cross-hole radar,and cross-hole electromagnetic imaging.The cross-hole radio imaging method currently only measures electric field strength data,and the operating frequency is low,generally a single frequency electromagnetic wave,and the frequency range is usually from 1 kHz to 10 MHz.Due to the lack of travel time data to correct the ray path,the cross-hole radio imaging method is mainly takes attenuation tomography based on direct ray tracing.The cross-hole radio imaging method can be used for both engineering and environmental geophysics as well as for prospecting.Cross-hole radar is a detection method of borehole radar.The highfrequency electromagnetic pulse is used to detect the change of dielectric constant and conductivity between two wells.Cross-hole radar tomography,also known as geological radar CT,can perform both traveltime imaging and attenuation imaging.In general,geological radar CT has a higher operating frequency of electromagnetic waves,and the center frequency is usually between 10 MHz and 1 GHz,so it has an advantage in resolution indicators.Cross-hole radar is mainly used for engineering and environmental geophysics.Crosshole electromagnetic imaging uses a lower frequency,measures complex electromagnetic signals,and is suitable for oil and gas reservoir monitoring.It is a geophysical frontier technology.Preliminary experiments in several test areas show that cross-well electromagnetic imaging is an effective means of reservoir research,which can be used to analyze the distribution of remaining oil and find oil and gas enrichment areas,so as to improve the success rate of drilling high-efficiency wells and improve oil recovery.This paper introduces in detail the characteristics of these three methods in theory and practice,and looks forward to the future development. |
| |
| Keywords: | Cross-hole electromagnetic method Cross-hole radio imaging method Cross-hole radar Cross-hole electromagnetic imaging |
| 本文献已被 CNKI 维普 等数据库收录！ |
|
