Invention Grant
- Patent Title: Method for making downhole electromagnetic logging while drilling measurements
- Patent Title (中): 钻井测量时进行井下电磁测井的方法
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Application No.: US14285581Application Date: 2014-05-22
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Publication No.: US09581721B2Publication Date: 2017-02-28
- Inventor: Mark Frey
- Applicant: Schlumberger Technology Corporation
- Applicant Address: US TX Sugar Land
- Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
- Current Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
- Current Assignee Address: US TX Sugar Land
- Main IPC: G01V3/26
- IPC: G01V3/26 ; G01V3/38 ; G01V3/30

Abstract:
A method for obtaining fully gain compensated propagation measurements includes rotating an electromagnetic logging while drilling tool in a subterranean wellbore. The tool includes first and second transmitters and first and second receivers axially spaced apart from one another in which each of the transmitters and each of the receivers include an axial antenna and collocated first and second transverse antennas. The first and second transverse antennas in the first receiver are rotationally offset by a predefined angle from the first and second transverse antennas in the first transmitter. A plurality of electromagnetic voltage measurements are acquired at the first and second receivers while rotating and processed to compute harmonic coefficients. The harmonic coefficients are mathematically rotated through at least the predefined angle to obtain rotated coefficients. Ratios of selected ones of the rotated coefficients are processed to compute fully gain compensated measurement quantities.
Public/Granted literature
- US20150276967A1 Compensated Tri-Axial Propagation Measurements Public/Granted day:2015-10-01
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