帅达^1,2,,
魏建新^1,2,
狄帮让^1,2,
黄兴兴^1,2,
刘子淳^1,2,
苏慧敏^1,2
1. 油气资源与探测国家重点实验室, 中国石油大学(北京), 北京 102249
2. CNPC物探重点实验室, 中国石油大学(北京), 北京 102249

基金项目: 国家科技重大专项（2017ZX05005-004）和国家自然科学基金（41474112，41811530095）资助


详细信息

作者简介: 帅达, 男, 1991年生, 中国石油大学(北京)在读博士, 目前主要从事裂缝各向异性、岩石物理学、地震物理模拟方面的研究.E-mail:cup.shuaida@qq.com

中图分类号: P631

收稿日期:2018-05-18
修回日期:2018-11-06
上线日期:2019-07-05

Physical modeling of the influence of crack density on the accuracy of effective medium theory

SHUAI Da^1,2,,
WEI JianXin^1,2,
DI BangRang^1,2,
HUANG XingXing^1,2,
LIU ZiChun^1,2,
SU HuiMin^1,2
1. State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum-Beijing, Beijing 102249, China
2. CNPC Key Laboratory of Geophysical Exploration, China University of Petroleum-Beijing, Beijing 102249, China


MSC: P631

--> Received Date: 18 May 2018
Revised Date: 06 November 2018
Available Online: 05 July 2019


摘要
摘要:为了比较裂缝等效介质理论的预测精度，本文利用物理模拟的方法制作了一组9个裂隙密度模型，其中裂隙密度从0增大到12%，裂隙厚度和直径保持不变，分别为0.12 mm和3 mm.使用0.5 MHz的纵横波换能器，采用脉冲透射法得到纵横波的速度和各向异性.然后，将基质的模量、裂缝填充物模量和裂缝参数代入等效介质理论中，计算出纵横波速度和各向异性随着裂隙密度的变化情况.通过纵横波速度的实测值与等效介质理论的定量对比，发现当裂隙密度小于12%时，Hudson理论和线性滑动理论对纵波速度的预测与实测值非常吻合.当裂隙密度小于8%时，Hudson理论和线性滑动理论对快横波速度的预测与实测值非常吻合.当裂隙密度小于9%时，各向异性自洽理论和NIA（非相互作用近似）理论对慢横波速度的预测与实测值非常吻合.通过纵横波速度各向异性实测值与理论计算值定量对比，发现当裂隙密度小于12%时，Hudson理论和线性滑动理论对纵波速度各向异性的预测与实测值更吻合；当裂隙密度小于6%时，各向异性自洽理论和NIA理论对横波速度各向异性的预测与实测值更吻合.
关键词: 岩石物理/
等效介质理论/
物理模型/
裂隙密度/
纵横波速度/
各向异性

Abstract:In order to investigate the prediction accuracy of the effective medium theory, we construct a series of crack density models, in which crack density ranges from 0 to 12%, crack aperture and diameter fix at 0.12 mm and 3 mm, respectively. We use the 0.5 MHz transducers to measure the elastic velocity and anisotropy of these crack models, then compare the measurement results with those from the effective medium theory. Comparison suggests that when the crack density is less than 12%, the Hudson theory and the Linear Slip theory's predictions about the P-wave velocity fit with experimental results very well. When the crack density is less than 8%, the Hudson theory and the Linear Slip theory's predictions about the fast S-wave velocity fit with experimental results very well. And when the crack density is less than 9%, the anisotropic SCA and the NIA's predictions about the slow S-wave velocity match with experimental results very well. In addition, when the crack density is less than 12%, the Hudson theory and the Linear Slip theory's prediction about ε fit good with experimental results. When the crack density is less than 6%, the anisotropic SCA and the NIA's prediction about γ are more consistent with real measurements.
Key words:Rock physics/
Effective medium theory/
Physical model/
Crack density/
Elastic wave velocity/
Anisotropy



PDF全文下载地址:

http://www.geophy.cn/data/article/export-pdf?id=dqwlxb_15067