发明名称 |
Electromagnetic and magnetostatic shield to perform measurements ahead of the drill bit |
摘要 |
A transmitter on a bottomhole assembly (BHA) is used for generating a transient electromagnetic signal in an earth formation. A pair of receivers on the BHA receive signals that are indicative of formation resistivity and distances to bed boundaries. A time dependent calibration factor or a time-independent calibration factor may be used to combine the two received signals and estimate the distance to bed boundaries that are unaffected by the drill conductive body. Further improvement can be obtained by using copper shielding.
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申请公布号 |
US7994790(B2) |
申请公布日期 |
2011.08.09 |
申请号 |
US20090401440 |
申请日期 |
2009.03.10 |
申请人 |
BAKER HUGHES INCORPORATED |
发明人 |
ITSKOVICH GREGORY B.;CHEMALI ROLAND E.;WANG TSILI |
分类号 |
G01V3/08;G01V3/10 |
主分类号 |
G01V3/08 |
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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