欧洋^1,2,,
高文利^1,2,
李洋^1,2,
王宇航^1,2
1. 自然资源部地球物理电磁法探测技术重点实验室, 河北廊坊 065000
2. 中国地质科学院地球物理地球化学勘查研究所, 河北廊坊 065000

基金项目: 国家高技术研究发展"863"计划（2014AA06A608）和中国地质科学院基本科研业务费项目（AS2016J06，AS2017J09，JYYWF20180102）联合资助


详细信息

作者简介: 欧洋, 男, 1987年生, 工程师, 硕士, 主要从事地球物理数据解释方面的工作.E-mail:ouyang@igge.cn

中图分类号: P631

收稿日期:2018-07-05
修回日期:2019-07-23
上线日期:2019-10-05

Cross-well electromagnetic imaging method with radiation parameter estimation

OU Yang^1,2,,
GAO WenLi^1,2,
LI Yang^1,2,
WANG YuHang^1,2
1. Key Laboratory of Geophysical Electromagnetic Probing Technologies of Ministry of Natural Resources, Hebei Langfang 065000, China
2. Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Science, Hebei Langfang 065000, China


MSC: P631

--> Received Date: 05 July 2018
Revised Date: 23 July 2019
Available Online: 05 October 2019


摘要
摘要:为了避免使用不合理初始辐射场强和方向性因子带来的误差，研究了估计辐射参数的井间电磁波层析成像技术.通过时域有限差分法模拟表明，天线长度与波长的比值、钻孔充填情况、钻孔周围介质的物性均会影响偶极天线的初始辐射场强或方向性因子；为此结合已知的分层资料，将它们设为未知参数，并设定初始辐射场强与发射点位置相关，方向性因子随射线角度而变化；采用正则化反演方法，由钻孔资料建立了模型方差目标函数，使得反演结果与钻遇的地质特征保持一致.通过理论模型试验和实例应用分析表明，相对于传统射线层析成像方法，估计辐射参数的正则化层析成像技术有助于提高反演的准确性.
关键词: 井间电磁波/
层析成像/
时域有限差分法/
初始辐射场强/
方向性因子

Abstract:We present a ray-based amplitude tomography with radiation parameters estimation for cross-well radio-frequency electromagnetic data, which permits to avoid distortions from utilizing incorrect source strength and radiation pattern. Numerical simulations using the finite difference time domain method indicate that the source strength and radiation pattern are seriously affected by the ratio of antenna length to wavelength, the filling of borehole and properties of the surrounding materials. To solve these problems, combining with the existing stratified data, the source strength and radiation pattern are treated as unknown parameters with the assumption that the source strength varies with the position of the transmitter and radiation pattern changes with the ray angle. The regularization inversion method is adopted, and constraints are applied to the model according to the geological features of the boreholes revealed to make inversion results in accordance with geological characteristics from drilling. Tests on theoretical models and field data show that this regularized tomography technique with radiation parameters estimation can help improve the accuracy of inversion compared with traditional ray-based tomography.
Key words:Cross-hole electromagnetic wave/
Tomography/
Finite difference time domain method/
Source strength/
Radiation pattern



PDF全文下载地址:

http://www.geophy.cn/data/article/export-pdf?id=dqwlxb_15193