公开(公告)号：US5463320A

公开(公告)日：1995-10-31

申请号：US259849

申请日：1994-06-15

申请人： Stephen D. Bonner ,  Richard A. Rosthal ,  Abdullah A. Bagersh ,  Martin G. Luling ,  Jacques A. Jundt

发明人： Stephen D. Bonner ,  Richard A. Rosthal ,  Abdullah A. Bagersh ,  Martin G. Luling ,  Jacques A. Jundt

IPC分类号： G01V3/20 ,  G01V3/18

CPC分类号： G01V3/20

摘要： A logging tool for use in determining the resistivity of an underground formation surrounding a borehole comprises a mandrel with two transmitters spaced apart thereon, each serving to establish a current in the mandrel and in the underground formation. A series of electrodes are spaced along the body between the transmitters and sensors, located at each electrode, measure radial current flow along a path from the mandrel to the underground formation via a respective electrode. Sensors also provide the axial current flowing along the whole mandrel and at positions corresponding to each electrode. A method of determining the formation resistivity includes the steps of measuring the radial currents R.sub.1 R.sub.2 from the mandrel to the formation via each electrode and obtaining the axial currents M.sub.01 M.sub.02 along the mandrel at each electrode due to each transmitter; measuring the total axial current M.sub.12 along the mandrel from the first or second transmitter and deriving the resistivity of the formation from the radial focused current R.sub.c for each electrode according to the relationship R.sub.c =1/M.sub.21 (M.sub.02 R.sub.1 +M.sub.01 R.sub.2).

摘要翻译： 用于确定围绕钻孔的地下地层的电阻率的测井工具包括具有间隔开的两个发射器的心轴，每个用于在心轴和地下地层中建立电流。 位于每个电极处的发射器和传感器之间的一系列电极沿主体间隔开，测量沿着从心轴经由相应电极到地下地层的路径的径向电流。 传感器还提供沿着整个心轴和对应于每个电极的位置流动的轴向电流。 确定地层电阻率的方法包括以下步骤：通过每个电极测量从心轴到地层的径向电流R1R2，并且由于每个发射器获得每个电极处的心轴处的轴向电流M01M02; 根据Rc = 1 / M21（M02R1 + M01R2）的关系，从第一或第二发射器测量沿着心轴的总轴向电流M12，并从每个电极的径向聚焦电流Rc导出地层的电阻率。

公开(公告)号：US5339037A

公开(公告)日：1994-08-16

申请号：US955101

申请日：1992-10-09

申请人： Stephen D. Bonner ,  Richard A. Rosthal ,  Abdullah A. Bagersh

发明人： Stephen D. Bonner ,  Richard A. Rosthal ,  Abdullah A. Bagersh

IPC分类号： G01V3/20 ,  G01V3/18

CPC分类号： G01V3/20

摘要： An apparatus for determining the resistivity of formations surrounding an earth borehole. An elongated electrically conductive body is movable through the borehole. A first transmitter establishes a first current in the body from a first transmitter position on the body, the first current traveling in a path that includes the body and the formations. An electrode is mounted on the body and has a surface that is electrically isolated from the surface of the body. A first electrical signal, resulting from the first current, is measured at the electrode. A second transmitter establishes a second current in the body from a second transmitter position on the body that is spaced from the first transmitter position, the second current traveling in a path that includes the body and the formations. A second electrical signal, resulting from the second current, is measured at the electrode. A current monitor measures the axial current passing a monitor position on the body to obtain a monitor current value. An indication of formation resistivity is derived as a function of the first electrical signal, the second electrical signal, and the monitor current value.

摘要翻译： 用于确定围绕地球钻孔的地层电阻率的装置。 细长的导电体可移动穿过钻孔。 第一发射器从身体上的第一发射器位置在身体中建立第一电流，第一电流在包括身体和地层的路径中行进。 电极安装在主体上并且具有与主体表面电隔离的表面。 在电极处测量由第一电流产生的第一电信号。 第二发射机从身体上与第一发射器位置间隔开的第二发射器位置在身体中建立第二电流，第二电流在包括身体和地层的路径中行进。 在电极处测量由第二电流产生的第二电信号。 电流监视器测量通过身体上的监视器位置的轴向电流以获得监视器电流值。 导出地层电阻率的指示作为第一电信号，第二电信号和监视电流值的函数。