发明名称 |
Estimating formation stress using borehole monopole and cross-dipole acoustic measurements: theory and method |
摘要 |
A system and method to determine an in-situ stress field based on borehole acoustic monopole and cross-dipole measurements. A radially polarized monopole shear-wave is generated in a borehole. It is then determined whether the shear-wave has split into two shear-waves. If it has, the difference in velocities between the two split shear-waves is used to determine the stress induced anisotropy around and near the borehole. The difference in velocities of cross-dipole shear-waves and the direction of the fast shear-wave are measured and used to determine the magnitude of the maximum shear stress and the maximum stress orientation of the geologic formation. Furthermore, a method of determining the stress-velocity coupling coefficients from laboratory measurements as well as through field measurement calibration is disclosed. The effect of borehole pressure on the field measurement calibration method of determining the stress-velocity coupling coefficients is taken into account. Additionally disclosed is a method for defining a stress indicator that is related to stress-caused rock deformation. This stress indicator can be used to determine if rock failure is impending and is useful in sand control and borehole stability applications.
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申请公布号 |
US6098021(A) |
申请公布日期 |
2000.08.01 |
申请号 |
US19990232564 |
申请日期 |
1999.01.15 |
申请人 |
BAKER HUGHES INCORPORATED |
发明人 |
TANG, XIAOMING;CHENG, NINGYA;CHENG, ARTHUR C. H. |
分类号 |
G01V1/50;(IPC1-7):G01V1/28 |
主分类号 |
G01V1/50 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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