CN111810116A - Method and device for measuring apparent resistivity of logging while drilling resistivity and readable storage medium - Google Patents

Method and device for measuring apparent resistivity of logging while drilling resistivity and readable storage medium Download PDF

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CN111810116A
CN111810116A CN202010606208.3A CN202010606208A CN111810116A CN 111810116 A CN111810116 A CN 111810116A CN 202010606208 A CN202010606208 A CN 202010606208A CN 111810116 A CN111810116 A CN 111810116A
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coil
drill collar
current
axial
focusing position
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CN111810116B (en
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陈思嘉
陈刚
尤嘉祺
唐章宏
许月晨
阳质量
郭怡潇
闫麦奎
孙衍
陈亮
马丽
靳敏刚
付浩
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China National Petroleum Corp
China Petroleum Logging Co Ltd
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China Petroleum Logging Co Ltd
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B47/00—Survey of boreholes or wells
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B47/00—Survey of boreholes or wells
    • E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
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    • Y02A90/30—Assessment of water resources

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Abstract

The invention belongs to the technical field of resistivity logging while drilling, and discloses a resistivity logging while drilling apparent resistivity measuring method, equipment and a readable storage medium, wherein the measuring method comprises the following steps: acquiring axial current of the drill collar at a focusing position when the first coil and the second coil are alternately transmitted; scaling the transmit current of the first coil and the second coil; the axial current of the drill collar at the preset focusing position when the first coil is emitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is emitted, and the axial currents are opposite in direction; correspondingly scaling the current measured by the measuring electrode when the first coil is transmitted and the current measured by the measuring electrode when the second coil is transmitted; and obtaining apparent resistivity according to the scaling result and the voltage of the second coil drill collar. The current flows out perpendicular to the surface of the drill collar at the focusing position to form a soft focusing effect, so that the accuracy of detecting the apparent resistivity of the stratum is effectively improved, and the problem that the measurement result of the logging-while-drilling instrument is inaccurate in a high-resistance area is solved.

Description

Method and device for measuring apparent resistivity of logging while drilling resistivity and readable storage medium
Technical Field
The invention belongs to the technical field of resistivity logging while drilling, and relates to a resistivity logging while drilling apparent resistivity measurement method, equipment and a readable storage medium.
Background
In oil exploration and development engineering, resistivity is a very important parameter for distinguishing formation information. In the apparent resistivity measuring method, the resistivity logging while drilling can detect the formation resistivity while drilling, and the true formation resistivity is inverted in real time. Compared with the cable resistivity logging, the resistivity logging while drilling does not need to be performed in advance and then measurement is performed, so that the processes of well cementation and measurement after drilling are omitted, the exploration cost is greatly reduced, the exploration speed is greatly improved, and the application of the resistivity logging while drilling is more and more extensive.
In the actual logging while drilling process, when complex formations such as cracks, collapse and thin layers are often encountered, and the situation that the porosity and permeability of rocks are low is also met, the traditional logging while drilling instrument meets great difficulty and challenge in the aspect of resistivity measurement for the complex high-resistance formations in the highly deviated well/horizontal well detection process, so that the azimuth resistivity measurement for the high-resistance complex formations becomes a key difficult problem. The traditional logging-while-drilling instrument often has the problem of inaccurate measurement results when the traditional logging-while-drilling instrument is in a high-resistance stratum, mainly the stratum resistance is too large, all emitted current flows back to a drill collar from mud and cannot flow through the stratum, and the apparent resistivity of the detected stratum is inaccurate.
Disclosure of Invention
The invention aims to overcome the defect that the apparent resistivity measurement of a high-resistance stratum in the prior art is inaccurate, and provides a method and equipment for measuring the apparent resistivity of a logging while drilling resistivity and a readable storage medium.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
in the first aspect of the invention, a logging while drilling resistivity apparent resistivity measuring method is characterized in that a plurality of azimuth measuring electrodes and a plurality of coils are arranged on a drill collar instrument, the plurality of coils are annularly wound on the drill collar instrument, each coil can transmit and receive current, a focusing position is preset on the drill collar instrument, one side of the preset focusing position at least comprises a first coil, and the other side of the preset focusing position at least comprises a second coil; the plurality of azimuth measuring electrodes are arranged between the first coil and the second coil; the measuring method comprises the following steps:
s1: acquiring axial current of the drill collar at a focusing position when the first coil and the second coil are alternately transmitted;
s2: adjusting the transmitting current of the first coil according to a first scaling factor, and adjusting the transmitting current of the second coil according to a second scaling factor; the axial current of the drill collar at the preset focusing position when the first coil is emitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is emitted, and the axial currents are opposite in direction;
s3: the current measured by the measuring electrode when the first coil emits is zoomed by a first zoom multiple, and the current of the first measuring electrode is obtained; the current measured by the measuring electrode when the second coil transmits is zoomed by a second zoom multiple, so that the current of the second measuring electrode is obtained;
s4: and obtaining apparent resistivity according to the first measuring electrode current, the second measuring electrode current and the second coil drill collar voltage, wherein when the second coil drill collar voltage is transmitted by the second coil, the axial current generated in the drill collar is 1A, and the voltage of the drill collar at the second coil is obtained.
The invention further improves the measurement method of the logging-while-drilling resistivity and the apparent resistivity, which comprises the following steps:
and a gap is reserved between the preset focusing position and the axial upper edge and the axial lower edge of any coil.
When the coil is arranged at the preset focusing position, the axial current of the drill collar at the focusing position is obtained through the following formula:
IRi＝NRiI′Ri
wherein, IRiThe axial current of the drill collar at the position of the coil Ri at the focusing position is represented; n is a radical ofRiRepresents the number of turns of coil Ri at the focus position; i'RiIndicating the current of the coil Ri at the focus position.
When no coil is arranged at the preset focusing position, defining coils with the shortest distance at two sides of the focusing position as a third coil and a fourth coil; the axial current of the drill collar at the focus position is obtained by the following formula:
Figure BDA0002561115750000031
Figure BDA0002561115750000032
wherein, I10The axial current of the drill collar at the focusing position when the axial current of the drill collar is 1A during the emission of the first coil is shown; i is20When the second coil is used for transmitting, when the axial current of the drill collar is 1A, the axial current of the drill collar at the focusing position is shown; d30Represents the center distance of the third coil to the focus position; d40Represents the center distance of the fourth coil to the focus position; i is13The axial current of the drill collar at the third coil is 1A when the first coil emits; i is14The axial current of the drill collar at the fourth coil is shown when the axial current of the drill collar is 1A when the first coil is transmitted; i is23The axial current of the drill collar at the third coil is 1A when the second coil transmits; i is24And when the axial current of the drill collar is 1A when the second coil transmits, the axial current of the drill collar at the fourth coil is shown.
The specific method of S4 is as follows:
the apparent resistivity R is obtained by the following formulaaL：
Figure BDA0002561115750000033
Wherein, VT2The voltage of the second coil drill collar is shown, when the voltage of the second coil drill collar is transmitted by the second coil, and the axial current generated in the drill collar is 1A, the voltage of the drill collar at the second coil is shown; i isM1When the first coil emits, when the axial current of the drill collar is 1A, the current of the electrode is measured; i isM2When the axial current of the drill collar is 1A when the second coil is transmitted, the current of the electrode is measured; a represents a scaling factor of the transmission current of the first coil; b represents a scaling factor of the transmission current of the second coil;
KLcalculating an instrument constant in a linear soft focusing mode through an infinite uniform stratum model with the resistivity Rt:
Figure BDA0002561115750000041
in the second aspect of the invention, a resistivity logging while drilling visual resistivity measuring method is characterized in that a plurality of azimuth measuring electrodes and a plurality of coils are arranged on a drill collar instrument, the plurality of coils are annularly wound on the drill collar instrument, each coil can transmit and receive current, a focusing position, a first coil, a second coil, a third coil and a fourth coil are preset on the drill collar instrument, one side of the focusing position comprises the first coil and the third coil, and the distance between the first coil and the focusing position is far than that between the first coil and the third coil; the other side is provided with a second coil and a fourth coil, and the second coil is farther away from the focusing position than the fourth coil; the focusing position is a drill collar annular area formed by a third coil and a fourth coil which are adjacent, and the measuring method comprises the following steps:
s1: acquiring axial current of the drill collar at a focusing position when the first coil and the second coil are alternately transmitted;
s2: adjusting the transmitting current of the first coil according to a first scaling factor, and adjusting the transmitting current of the second coil according to a second scaling factor; the axial current of the drill collar at the preset focusing position when the first coil is emitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is emitted, and the axial currents are opposite in direction;
s3: zooming the current flowing out from the focusing position when the first coil is transmitted by a first zooming multiple to obtain a first focusing position current; zooming the current flowing out of the focusing position when the second coil is transmitted by a second zooming multiple to obtain a second focusing position current;
s4: and obtaining apparent resistivity according to the first focusing position current, the second focusing position current and the second coil drill collar voltage, wherein when the second coil drill collar voltage is transmitted by the second coil, the axial current generated in the drill collar is 1A, and the voltage of the drill collar at the second coil is obtained.
The invention further improves the measurement method of the logging-while-drilling resistivity and the apparent resistivity, which comprises the following steps:
the axial current of the drill collar at the focusing position is obtained by the following formula:
Figure BDA0002561115750000042
Figure BDA0002561115750000051
wherein, I10The axial current of the drill collar at the focusing position when the axial current of the drill collar is 1A during the emission of the first coil is shown; i is20When the second coil is used for transmitting, when the axial current of the drill collar is 1A, the axial current of the drill collar at the focusing position is shown; i is13The axial current of the drill collar at the third coil is 1A when the first coil emits; i is14The axial current of the drill collar at the fourth coil is shown when the axial current of the drill collar is 1A when the first coil is transmitted; i is23The axial current of the drill collar at the third coil is 1A when the second coil transmits; i is24And when the axial current of the drill collar is 1A when the second coil transmits, the axial current of the drill collar at the fourth coil is shown.
The specific method of S4 is as follows:
the apparent resistivity R is obtained by the following formulaaC：
Figure BDA0002561115750000052
Wherein, VT2The voltage of the second coil drill collar is shown, when the voltage of the second coil drill collar is transmitted by the second coil, and the axial current generated in the drill collar is 1A, the voltage of the drill collar at the second coil is shown; i is21When the second coil is used for transmitting, the axial current of the drill collar at the first coil is 1A;
KCthe method is characterized in that the method is an instrument constant in an annular soft focusing mode, and is calculated through an infinite uniform stratum model with the resistivity Rt:
Figure BDA0002561115750000053
in a third aspect of the present invention, a computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned resistivity logging while drilling apparent resistivity measurement method when executing the computer program.
In a fourth aspect of the present invention, a computer readable storage medium stores a computer program which, when executed by a processor, implements the steps of the above-described method for resistivity logging while drilling as a borehole resistivity measurement.
Compared with the prior art, the invention has the following beneficial effects:
the invention relates to a method for measuring the logging while drilling resistivity and the apparent resistivity, which comprises the steps of firstly obtaining the axial current of a drill collar at a focusing position when a first coil and a second coil are alternately transmitted, then the transmitting current of the first coil and the transmitting current of the second coil are adjusted according to the scaling factor, so that the axial current of the drill collar at the focusing position is zero, namely, the axial current of the drill collar at the preset focusing position when the first coil is emitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is emitted, and the axial currents are opposite in direction, thus, a soft focusing effect is formed at the focusing position, the current at the focusing position flows out vertical to the surface of the drill collar, thereby increasing the flowing distance of the emitted current in the stratum, the collected current can more accurately represent the characteristics of the stratum, and the measurement accuracy of the apparent resistivity of the detected stratum is further improved, so that key tasks of geosteering and stratum evaluation can be completed in the complex stratum.
Furthermore, different detection depths can be realized based on the adjustment of the focusing position, and various detection conditions are met.
Drawings
FIG. 1 is a flow chart of a method for synthesizing while-drilling resistivity logging data according to the present invention;
FIG. 2 is a schematic diagram of the position of a coil and an orientation measuring electrode of a logging-while-drilling instrument according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a winding of a coil according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of coil T2 operating alone in accordance with an embodiment of the present invention;
FIG. 5 is a schematic diagram of coil T3 operating alone in accordance with an embodiment of the present invention;
FIG. 6 is a schematic diagram of a shallow azimuth detection mode implemented by the simultaneous operation of the coil T2 and the coil T3 according to an embodiment of the present invention;
FIG. 7 is a schematic diagram of a detection mode in an orientation implemented by coil T2 and coil T3 operating simultaneously in accordance with an embodiment of the present invention;
FIG. 8 is a schematic diagram of coil T4 operating alone in accordance with an embodiment of the present invention;
FIG. 9 is a schematic diagram of coil T3 operating alone in accordance with an embodiment of the present invention;
FIG. 10 is a schematic diagram of coil T4 and coil T3 operating simultaneously to achieve a deep detection mode in azimuth in accordance with an embodiment of the present invention;
FIG. 11 is a schematic diagram of an embodiment of the present invention in which coil T4 and coil T3 operate simultaneously to implement an azimuth depth detection mode;
FIG. 12 is a schematic diagram of a loop detection mode implemented by the simultaneous operation of the coil T4 and the coil T3 according to an embodiment of the present invention.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1, the method for measuring the apparent resistivity of the logging while drilling resistivity of the invention is firstly described by a linear soft focusing method. The method comprises the following steps that a plurality of azimuth measuring electrodes and a plurality of coils are arranged on a drill collar instrument, the plurality of coils are wound on the drill collar instrument in an annular mode, each coil can transmit and receive current, a focusing position is preset on the drill collar instrument, one side of the preset focusing position at least comprises a first coil, and the other side of the preset focusing position at least comprises a second coil; a plurality of position-measuring electrodes are disposed between the first coil and the second coil.
The method for measuring the apparent resistivity of the resistivity logging while drilling comprises the following steps:
s1: and acquiring the axial current of the drill collar at the focusing position when the first coil and the second coil are alternately transmitted.
S2: adjusting the transmitting current of the first coil according to a first scaling factor, and adjusting the transmitting current of the second coil according to a second scaling factor; the axial current of the drill collar at the preset focusing position when the first coil is transmitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is transmitted, and the axial currents are opposite in direction.
S3: the current measured by the measuring electrode when the first coil emits is zoomed by a first zoom multiple, and the current of the first measuring electrode is obtained; and the current measured by the measuring electrode when the second coil transmits is zoomed by a second zoom multiple, so that the current of the second measuring electrode is obtained.
S4: and obtaining apparent resistivity according to the first measuring electrode current, the second measuring electrode current and the second coil drill collar voltage, wherein when the second coil drill collar voltage is transmitted by the second coil, the axial current generated in the drill collar is 1A, and the voltage of the drill collar at the second coil is obtained.
Based on the positions of the plurality of coils and the plurality of azimuth measuring electrodes which are annularly wound on the drill collar instrument, different coils are controlled to be combined and transmitted in a simulation mode, so that soft focusing effects are formed at different positions to achieve different detection depths, current at the focusing position can flow in the stratum for a longer distance, the apparent resistivity accuracy of the detected stratum is effectively improved, the problem that the measurement result of the logging-while-drilling instrument in a high-resistance area is inaccurate is solved, and the key tasks of geological guidance and stratum evaluation can be completed in the complex stratum.
The following describes in detail the steps of the method for measuring apparent resistivity of the logging while drilling resistivity of the present invention, and four coils are used as an example for illustration, but not limited thereto.
Referring to FIG. 2, the drill collar apparatus has 4 coils, T1/R1, T2/R2, T3/R3 and T4/R4, where T is used to indicate the transmitting state and R is used to indicate the receiving state. Distances from T1/R1, T2/R2, T3/R3 and T4/R4 to the orientation measuring electrode M are increased in sequence, T1/R1, T2/R2 and T4/R4 are above the orientation measuring electrode M, and T3/R3 is below the orientation measuring electrode M. In order to explain the working principle of the transmitting coil of the logging-while-drilling instrument, the T2 coil in a transmitting state is taken as an example to explain the working principle of the instrument, wherein the T2 coil is wound in the same way as that of the T2 coil in the way of referring to FIG. 3.
When the T2 coil transmits, the transformer principle is adopted, when the transmitting coil provides a low-frequency alternating signal, the inner part of the drill collar can generate current, and the expression is I-NT2IT2. Wherein N isT2Number of turns of coil T2, IT2The line current input to the T2 coil therefore only needs to be supplied to the T2 coil at a lower current, which is expressed as a larger current inside the drill collar. By adopting the transformer principle, the voltage of the T2 coil is given, and the expression of the drill collar voltage U at the position of the T2 coil can be calculated according to the expression, and the result is
Figure BDA0002561115750000091
Wherein VT2The line voltage input for the coil of T2. Conversely, when the coil is used as a receiving coil, the axial direction of the drill collar at the position of the receiving coil can be reversely pushed by measuring the line current of the receiving coilCurrent: i is NR2I′R2(ii) a Wherein I represents the axial current of the drill collar at the position of the R2 coil; i'R2Line current measured by the R2 coil is shown, and similarly the voltage of the drill collar at that location is inferred from the line voltage measured by R2:
Figure BDA0002561115750000092
wherein V'R2The line voltage measured for the R2 coil, and U is the voltage of the drill collar at the location of the R2 coil.
Because the azimuth measuring electrodes M are distributed on 4 quadrants, the azimuth measuring electrode M at the azimuth i is adopted in the process of deriving the formula, and M is usediAnd (4) showing.
Referring to FIG. 4, a schematic diagram of an embodiment of the present invention, when the T2 coil works alone, when the T2 coil inputs 1A alternating current, the inside of the drill collar is divided into a high-pressure region and a low-pressure region, wherein the lower part of the T2 coil is the high-pressure region, the upper part of the T2 coil is the low-pressure region, the high-pressure region current flows out from the surface of the drill collar, and the low-pressure region current flows in from the surface of the drill collar. The axial current in the drill collar at the T1 coil is I21Measuring the electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000103
The axial current in the drill collar at the R3 coil is I23。
Referring to FIG. 5, a schematic diagram of an embodiment of the present invention, when the T3 coil works alone, when the T3 coil inputs 1A alternating current, the inside of the drill collar is divided into a high-pressure region and a low-pressure region, wherein the upper part of the T3 coil is the high-pressure region, the lower part of the T3 coil is the low-pressure region, the high-pressure region current flows out from the surface of the drill collar, and the low-pressure region current flows in from the surface of the drill collar. The axial current in the drill collar at the T1 coil is I31Measuring the electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000102
The axial current in the drill collar at the R2 coil is I32From the principle of reciprocity, I can be obtained32＝I23。
Referring to fig. 6, in the apparatus according to the embodiment of the present invention, a schematic diagram of shallow azimuth detection when the T2 coil and the T3 coil operate simultaneously is shown, where the lower portion of the T2 coil and the upper portion of the T3 coil are high voltage regions, and the upper portion of the T2 coil and the lower portion of the T3 coil are low voltage regions. The axial currents at the R1 coil position inside the drill collar are equal in magnitude and opposite in direction by controlling the currents of the T2 coil and the T3 coil, and the radial current is concentrated to flow perpendicularly from the R1 coil position, so that the focusing effect is achieved, which is the detection mode 1 of the embodiment.
To achieve the above effect, the axial currents generated by the T2 coil and the T3 coil at the R1 coil are respectively I from fig. 4 and 521And I31To ensure equal axial current at the R1 coil, the input current ratio of the T2 coil to the T3 coil is I31/I21To increase the current signal, the input current of the coil T2 is set to I31/I32FIG. 5 shows that axial current flows through R2 after flowing through R1 in the drill collar, so that I31Is greater than I32When the T2 coil is working, the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000101
Let the input current of the coil T3 be I21/I23FIG. 4 shows that axial current flows through the R3 coil after flowing through the R1 coil inside the drill collar, so I21Is greater than I23When the T3 coil is working, the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000111
When the T2 coil and the T3 coil work simultaneously, the axial current at the R1 coil is equal due to the fact that the current ratio of the T2 coil and the T3 coil is controlled, and the radial current flowing out of the R1 coil flows out of the stratum perpendicular to the surface of the drill collar, so that the azimuth measuring electrode M is arranged on the position of the azimuth measuring electrode MiThe current at (a) is greatly affected by the position of R1. The focus position here is not at the measuring electrode MiInstead, the current is focused at R1, the focused schematic diagram is shown in FIG. 6, the focused current flows out perpendicular to the surface of the drill collar at R1, and the measuring electrode MiThere will still be an axial component, the axis of which is more axial than the conventional non-focusing modeThe directional component is small, so that the measuring electrode MiWith deeper probing depth, named shallow probing mode, measuring the electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000112
The expression for calculating the ith azimuthal apparent resistivity is:
Figure BDA0002561115750000113
in the formula KL1iThe instrument constant of the ith azimuth electrode in the 1 st detection mode is the pass resistivity of RtThe infinite homogeneous stratigraphic model of (2) is calculated:
Figure BDA0002561115750000114
wherein R isaL1iShowing the apparent resistivity of the ith azimuth electrode in the 1 st detection mode; i is23The method is characterized in that a T2 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R3 coil is shown; vT3The voltage of the drill collar at the T3 coil is shown when the T3 coil works and the induced current in the axial direction of the drill collar is 1A under the actual time-sharing transmitting condition;
Figure BDA0002561115750000115
the method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiThe current flowing out of the surface; i is21The method is characterized in that a T2 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R1 coil is shown;
Figure BDA0002561115750000116
the method shows that under the actual time-sharing transmitting condition, the T2 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiThe current flowing out of the surface; i is31The T3 coil works and is sensed in the axial direction of the drill collar under the condition of actual time-sharing transmissionWhen the current is 1A, the axial current of the drill collar at the R1 coil is obtained.
Referring to fig. 5, in the embodiment of the present invention, when coil T2 and coil T3 are operated simultaneously, the principle diagram of linear detection is shown, where the lower part of coil T2 and the upper part of coil T3 are high voltage regions, and the upper part of coil T2 and the lower part of coil T3 are low voltage regions. The current of the coil T2 and the coil T3 is controlled to enable the position measuring electrode M inside the drill collariThe axial currents at the positions are equal in magnitude and opposite in direction, and the radial currents are concentrated on the azimuth measuring electrode MiThe position is vertically discharged, and then the focusing effect is achieved, which is the 2 nd detection mode of this embodiment.
To achieve the above-mentioned effect, coil T2 and coil T3 are used to measure the position of electrode M in FIG. 4 and FIG. 5iAxial currents generated at the positions are respectively I20And I30To ensure the orientation measuring electrode MiAt equal axial current, the ratio of the input currents of the coil T2 and the coil T3 is I30/I20To increase the current signal, the input current of the coil T2 is set to I30/I32From FIG. 5, it can be obtained that the axial current flows through the azimuth measuring electrode M inside the drill collariThen flows through coil R2, so I30Is greater than I32When the coil T2 is in operation, the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000121
Let the input current of coil T3 be I20/I23From FIG. 4, it can be obtained that the axial current flows through the azimuth measuring electrode M inside the drill collariThen flows through R3, so I20Is greater than I23When the coil T3 is in operation, the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000122
When the coil T2 and the coil T3 are simultaneously operated, the current ratio of the coil T2 and the coil T3 is controlled so that the electrode M is measured in the azimuthiAxial currents are equal, and the azimuth measuring electrode M is arranged at the momentiWhere the current is perpendicular to the surface of the drill collar and is focused on the measuring electrode MiThe focused current is at MiIs flowing out perpendicular to the surface of the drill collar, so that the measuring electrode M in this modeiThe detection depth is deeper than that of a shallow detection mode, and the shallow detection mode has no axial component and is named as middle detection; from azimuth measuring electrode MiThe current flowing out is
Figure BDA0002561115750000123
The expression for calculating the ith azimuthal apparent resistivity is:
Figure BDA0002561115750000131
in the formula KL2iThe instrument constant of the ith azimuth electrode in the 2 nd detection mode is the pass resistivity of RtThe infinite homogeneous stratigraphic model of (2) is calculated:
Figure BDA0002561115750000132
wherein R isaL2iShowing the apparent resistivity of the ith azimuth electrode in the 2 nd detection mode; i is23The method is characterized in that under the actual time-sharing transmitting condition, a coil T2 works, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R3 coil is shown; vT3The voltage of the drill collar at the T3 coil is shown when the T3 coil works and the induced current in the axial direction of the drill collar is 1A under the actual time-sharing transmitting condition;
Figure BDA0002561115750000133
the method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiRadial current flowing out of the surface; i is20The method shows that under the actual time-sharing transmitting condition, the T2 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar;
Figure BDA0002561115750000134
the T2 coil works and is sensed in the axial direction of the drill collar under the condition of actual time-sharing transmissionWhen the current is 1A, the orientation measuring electrode MiRadial current flowing out of the surface; i is30The method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar.
Azimuth measuring electrode MiOnly the current flowing out of the drill collar at the position can be measured, the axial current at the position cannot be measured, and the axial current needs to pass through the azimuth measuring electrode MiThe axial current at the coils on both sides is found by linear interpolation, specifically expressed as:
Figure BDA0002561115750000135
Figure BDA0002561115750000136
wherein I30The method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar; i is20The method shows that under the actual time-sharing transmitting condition, the T2 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar; d10Representing R1 to the orientation measuring electrode MiThe center distance of (d); d30Representing R3 to the orientation measuring electrode MiThe center distance of (d); i is31The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of R1 is shown; i is33The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and the induced current in the axial direction of a drill collar is 1A; i is21The method is characterized in that a T2 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R1 coil is shown; i is23The method is characterized in that a T2 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of an R3 coil is shown.
Referring to FIG. 8, a schematic diagram of an embodiment of the present invention when the coil T4 operates alone, when the coil T4 inputs 1A alternatingWhen current flows, the interior of the drill collar is divided into a high-pressure area and a low-pressure area, wherein the lower part of the T4 coil is the high-pressure area, the upper part of the T4 coil is the low-pressure area, the current in the high-pressure area flows out of the surface of the drill collar, and the current in the low-pressure area flows in from the surface of the drill collar. The axial current in the drill collar at the R1 coil is I41Measuring the electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000142
The axial current in the drill collar at the R3 coil is I43。
Referring to fig. 9, according to the schematic diagram of the T3 coil alone, when the T3 coil inputs 1A alternating current, the inside of the drill collar is divided into a high-pressure region and a low-pressure region, wherein the upper part of the T3 coil is the high-pressure region, the lower part of the T3 coil is the low-pressure region, the high-pressure region current flows out of the surface of the drill collar, and the low-pressure region current flows in from the surface of the drill collar. The axial current in the drill collar at the R1 coil is I31Measuring the electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000141
The axial current in the drill collar at the R4 coil is I34From the principle of reciprocity, I can be obtained34＝I43。
Referring to fig. 10, the embodiment of the present invention is a schematic diagram of the 3 rd detection mode when the T4 coil and the T3 coil are operated simultaneously, wherein the lower portion of the T4 coil and the upper portion of the T3 coil are high voltage regions, and the upper portion of the T4 coil and the lower portion of the T3 coil are low voltage regions. The axial currents at the R1 coil position inside the drill collar are equal in magnitude and opposite in direction by controlling the currents of the T4 coil and the T3 coil, and the radial current is concentrated to flow out perpendicularly from the R1 coil position, so that the focusing effect is achieved, namely the 3 rd detection mode of the embodiment.
To achieve the above effect, the axial currents generated by the T4 coil and the T3 coil at the R1 coil are respectively I from fig. 8 and 941And I31To ensure equal axial current at the R1 coil, the input current ratio of the T4 coil to the T3 coil is I31/I41To increase the current signal, the input current of the coil T4 is set to I31/I34FIG. 9 shows that axial current flows through the R4 coil after flowing through the R1 coil inside the drill collar, so I31Is greater than I34When the T4 coil is working, the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000151
Let the input current of the coil T3 be I41/I43FIG. 8 shows that axial current flows through the R3 coil after flowing through the R1 coil inside the drill collar, so I41Is greater than I43At this time, T3 is operated to measure electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000152
When the T4 coil and the T3 coil work simultaneously, the current ratio of the T4 coil and the T3 coil is controlled, so that the axial current at the R1 coil is equal, and the radial current flowing out of the R1 coil flows out of the stratum perpendicular to the surface of the drill collar, so that the azimuth measuring electrode M worksiThe current at (a) is greatly affected by the position of the R1 coil. The focus position here is not at the measuring electrode MiInstead, the current is focused at R1, the focused schematic diagram is shown in FIG. 10, the focused current flows out perpendicular to the surface of the drill collar at the R1 coil, and the measuring electrode MiThere will be an axial component. However, the current return path in this mode is long, and the current in the first two modes flows back to the upper part of the T2 coil and the lower part of the T3 coil, and the return path is short. The current return path here is long and returns to the upper part of the T4 coil and the lower part of the T3 coil, so even though the current in this mode has an axial component, the return path becomes long and the probe depth increases, so that the electrode M is named as a medium-depth mode and is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000153
The expression for calculating the ith azimuthal apparent resistivity is:
Figure BDA0002561115750000154
in the formula KL3iThe instrument constant of the ith azimuth electrode in the 3 rd detection mode is calculated by an infinite uniform stratum model with the resistivity Rt:
Figure BDA0002561115750000161
wherein R isaL3iShowing the apparent resistivity of the ith azimuth electrode in the 3 rd detection mode; i is43The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of R3 is shown; vT4The voltage of the drill collar at the T4 coil is shown when the T4 coil works and the induced current in the axial direction of the drill collar is 1A under the actual time-sharing transmitting condition;
Figure BDA0002561115750000162
the method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiThe current flowing out of the surface; i is41The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of R1 is shown;
Figure BDA0002561115750000163
the method shows that under the actual time-sharing transmitting condition, the T4 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiThe current flowing out of the surface; i is31The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of an R1 coil is shown.
Referring to fig. 11, the embodiment of the present invention is a schematic diagram of the 4 th detection mode when the T4 coil and the T3 coil are operated simultaneously, in which the lower portion of the T4 coil and the upper portion of the T3 coil are high voltage regions, and the upper portion of the T4 coil and the lower portion of the T3 coil are low voltage regions. The current of the T4 coil and the T3 coil is controlled to enable the position measuring electrode M inside the drill collar to be measurediThe axial currents at the positions are equal in magnitude and opposite in direction, and the radial currents are concentrated on the azimuth measuring electrode MiThe position is vertically discharged, thereby achieving focusingThe effect is the 4 th detection mode of this embodiment.
To achieve the above effect, the T4 coil and the T3 coil in the azimuth measuring electrode M are obtained from the images of FIGS. 8 and 9iAxial currents generated at the positions are respectively I40And I30To ensure the orientation measuring electrode MiThe axial current is equal, and the ratio of the input currents of the T4 coil and the T3 coil is I30/I40To increase the current signal, the input current of the coil T4 is set to I30/I34From FIG. 9, it can be obtained that the axial current flows through the azimuth measuring electrode M inside the drill collariThen flows through the R2 coil, so I30Is greater than I34At this time, T4 is operated to measure electrode M from azimuthiThe current flowing out is
Figure BDA0002561115750000171
Let the input current of the coil T3 be I40/I43From FIG. 8, it can be obtained that the axial current flows through the azimuth measuring electrode M inside the drill collariThen flows through the R3 coil, so I40Is greater than I43When the T3 coil is working, the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000172
When the T4 coil and the T3 coil work simultaneously, the current ratio of the T4 coil and the T3 coil is controlled so that the electrode M is measured in the azimuthiAt an equal magnitude of the axial current, where the focus position is at the measuring electrode MiThe diagram after focusing is shown in FIG. 11, where the current after focusing is at MiIs flowing out perpendicular to the surface of the drill collar, so that the measuring electrode M in this modeiHas a longer current return path and no axial component, so that the probing depth is deepest, named deep probing mode, and the electrode M is measured from the azimuthiThe current flowing out is
Figure BDA0002561115750000173
The expression for calculating the ith azimuthal apparent resistivity is:
Figure BDA0002561115750000174
in the formula KL4iThe instrument constant of the ith azimuth electrode in the 4 th detection mode is the pass resistivity of RtThe infinite homogeneous stratigraphic model of (2) is calculated:
Figure BDA0002561115750000175
wherein R isaL4iShowing the apparent resistivity of the ith azimuth electrode in the 4 th detection mode; i is34The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R4 coil is shown; vT4The voltage of the drill collar at the position of T4 is shown when the T4 coil works and the induced current in the axial direction of the drill collar is 1A under the actual time-sharing transmitting condition;
Figure BDA0002561115750000176
the method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiRadial current flowing out of the surface; i is40The method shows that under the actual time-sharing transmitting condition, the T4 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar;
Figure BDA0002561115750000177
the method shows that under the actual time-sharing transmitting condition, the T4 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiRadial current flowing out of the surface; i is30The method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar.
Azimuth measuring electrode MiOnly the current flowing out of the drill collar at the position can be measured, the axial current at the position cannot be measured, and the axial current needs to pass through the azimuth measuring electrode MiThe axial currents at the coils on both sides are found by linear interpolation, specifically expressed as
Figure BDA0002561115750000181
Figure BDA0002561115750000182
Wherein I30The method shows that under the actual time-sharing transmitting condition, the T3 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar; i is40The method shows that under the actual time-sharing transmitting condition, the T4 coil works, and when the induced current in the axial direction of the drill collar is 1A, the azimuth measuring electrode MiAxial current of the drill collar; d10Representing the R1 coil to the orientation measuring electrode MiThe center distance of (d); d30Representing the R3 coil to the orientation measuring electrode MiThe center distance of (d); i is31The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of R1 is shown; i is33The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and the induced current in the axial direction of a drill collar is 1A; i is41The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R1 coil is shown; i is43The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of an R3 coil is shown.
The invention also discloses a logging while drilling resistivity well-logging apparent resistivity measuring method, in order to achieve deeper focusing effect, a method of 'annular' electrode focusing is adopted, wherein a drill collar part between an R1 coil and an R2 coil is equivalent to a large ring, the current magnitude of a T4 coil and a T3 coil during working is controlled, so that the axial current at the equivalent annular electrode is equal, and the specific derivation process of the annular soft focusing principle is as follows:
when the T4 coil works, the current flowing out of the drill collar between the R1 coil and the R2 coil is (I)42-I41) And the axial current of the drill collar at the position between the R1 coil and the R2 coil is I40(ii) a When the T3 coil works, the current flowing out of the drill collar between the R1 coil and the R2 coil is (I)31-I32) And the axial current of the drill collar at the position between the R1 coil and the R2 coil is I30In order to ensure that the axial currents of the drill collar at the middle positions from R1 to R2 are equal, the input current ratio of the T4 coil to the T3 coil is I30/I40To increase the current signal, the input current of the coil T4 is set to I30/I34I can be obtained in the same way30Is greater than I34When the T4 coil is operated, the current flowing from the ring electrode at the position between the R1 coil and the R2 coil is
Figure BDA0002561115750000191
Let the input current of the coil T3 be I40/I43I can be obtained in the same way40Is greater than I43When the T3 coil is operated, the current flowing from the ring electrode between the R1 coil and the R2 coil is equal to
Figure BDA0002561115750000192
When the T4 coil and the T3 coil work simultaneously, the current ratio of the T4 coil and the T3 coil is controlled, so that the axial currents of the drill collar at the middle position between the R1 coil and the R2 coil are equal, and at the moment, the currents flowing out of the ring-shaped electrode at the position between the R1 coil and the R2 coil are all equivalent to flow out perpendicular to the surface of the drill collar, and the mode is called as a ring-shaped soft focusing mode and is a detection mode 5 in the embodiment. At this time, the current flowing from the ring-shaped electrode at the position between the R1 coil and the R2 coil was set to
Figure BDA0002561115750000193
The apparent resistivity is expressed as:
Figure BDA0002561115750000194
since the axial current of the drill collar cannot be measured at the middle position from the R1 coil to the R2 coil, an average method is adopted, and the method is specifically expressed as follows:
Figure BDA0002561115750000195
Figure BDA0002561115750000201
substituting the expression to obtain:
Figure BDA0002561115750000202
in the formula KCFor the instrument constant in the 5 th detection mode, the calculation is carried out through an infinite uniform stratum model with the resistivity Rt:
Figure BDA0002561115750000203
wherein R isaCRepresenting the apparent resistivity calculated in the annular probing mode; i is43The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R3 coil is shown; vT4The voltage of the drill collar at the T4 coil is shown when the T4 coil works and the induced current in the axial direction of the drill collar is 1A under the actual time-sharing transmitting condition; i is31The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R1 coil is shown; i is42The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R2 coil is shown; i is32The method is characterized in that a T3 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the R2 coil is shown; i is41The method is characterized in that a T4 coil works under the actual time-sharing transmitting condition, and when the induced current in the axial direction of the drill collar is 1A, the axial current of the drill collar at the position of an R1 coil is shown.
Compared with the prior art, the embodiment of the invention adopts a novel soft focusing calculation method aiming at the problem that the measurement of the traditional azimuth lateral resistivity imaging instrument is inaccurate in a high-resistance area, simulates two equivalent transmitting coils to work simultaneously by transmitting current at the transmitting electrodes on two sides of a focusing position in a time-sharing manner, and controls the output current ratio of the transmitting coils to realize focusing remote detection; different transmitting coils work and different focusing positions are adopted, wherein linear soft focusing is realized by focusing at the position of the azimuth measuring electrode, and annular soft focusing is realized by focusing at the position of the drill collar equivalent annular electrode, so that different detection modes are obtained. The invention can effectively solve the problem that the measurement result of the logging-while-drilling instrument in the high resistance area is inaccurate by a soft focusing method, so that the key tasks of geological guidance and stratum evaluation can be completed in the complex stratum.
The resistivity logging while drilling apparent resistivity measurement methods of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. If the method for measuring the resistivity while drilling and the logging apparent resistivity is realized in the form of a software functional unit and is sold or used as an independent product, the method can be stored in a computer readable storage medium.
Based on such understanding, in the exemplary embodiment, a computer readable storage medium is also provided, all or part of the processes in the method of the above embodiments of the present invention can be realized by a computer program to instruct related hardware, the computer program can be stored in the computer readable storage medium, and when the computer program is executed by a processor, the steps of the above method embodiments can be realized. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. Computer-readable storage media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. It should be noted that the computer readable medium may contain content that is subject to appropriate increase or decrease as required by legislation and patent practice in jurisdictions, for example, in some jurisdictions, computer readable media does not include electrical carrier signals and telecommunications signals as is required by legislation and patent practice. The computer storage medium may be any available medium or data storage device that can be accessed by a computer, including but not limited to magnetic memory (e.g., floppy disk, hard disk, magnetic tape, magneto-optical disk (MO), etc.), optical memory (e.g., CD, DVD, BD, HVD, etc.), and semiconductor memory (e.g., ROM, EPROM, EEPROM, nonvolatile memory (NANDFLASH), Solid State Disk (SSD)), etc.
In an exemplary embodiment, a computer device is also provided, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of the various embodiment methods when executing the computer program. The processor may be a Central Processing Unit (CPU), other general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, etc.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.

Claims (10)

1. A resistivity logging while drilling apparent resistivity measuring method is characterized in that a plurality of azimuth measuring electrodes and a plurality of coils are arranged on a drill collar instrument, the plurality of coils are annularly wound on the drill collar instrument, each coil can transmit and receive current, a focusing position is preset on the drill collar instrument, one side of the preset focusing position at least comprises a first coil, and the other side of the preset focusing position at least comprises a second coil; the plurality of azimuth measuring electrodes are arranged between the first coil and the second coil; the measuring method comprises the following steps:
s1: acquiring axial current of the drill collar at a focusing position when the first coil and the second coil are alternately transmitted;
s2: adjusting the transmitting current of the first coil according to a first scaling factor, and adjusting the transmitting current of the second coil according to a second scaling factor; the axial current of the drill collar at the preset focusing position when the first coil is emitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is emitted, and the axial currents are opposite in direction;
s3: the current measured by the measuring electrode when the first coil emits is zoomed by a first zoom multiple, and the current of the first measuring electrode is obtained; the current measured by the measuring electrode when the second coil transmits is zoomed by a second zoom multiple, so that the current of the second measuring electrode is obtained;
s4: and obtaining apparent resistivity according to the first measuring electrode current, the second measuring electrode current and the second coil drill collar voltage, wherein when the second coil drill collar voltage is transmitted by the second coil, the axial current generated in the drill collar is 1A, and the voltage of the drill collar at the second coil is obtained.
2. The method of measuring while-drilling resistivity log apparent resistivity as recited in claim 1 wherein a gap is left between the predetermined focus position and the upper and lower axial edges of any coil.
3. The resistivity while drilling logging apparent resistivity measurement method as recited in claim 1, wherein when the coil is set at the preset focus position, the axial current of the drill collar at the focus position is obtained by the following formula:
IRi＝NRiI′Ri
wherein, IRiThe axial current of the drill collar at the position of the coil Ri at the focusing position is represented; n is a radical ofRiRepresents the number of turns of coil Ri at the focus position; i'RiIndicating the current of the coil Ri at the focus position.
4. The resistivity while drilling logging apparent resistivity measurement method as recited in claim 1, wherein when no coil is arranged at the preset focusing position, coils closest to both sides of the focusing position are defined as a third coil and a fourth coil; the axial current of the drill collar at the focus position is obtained by the following formula:
Figure FDA0002561115740000021
Figure FDA0002561115740000022
wherein, I10The axial current of the drill collar at the focusing position when the axial current of the drill collar is 1A during the emission of the first coil is shown; i is20When the second coil is used for transmitting, when the axial current of the drill collar is 1A, the axial current of the drill collar at the focusing position is shown; d30Represents the center distance of the third coil to the focus position; d40Represents the center distance of the fourth coil to the focus position; i is13The axial current of the drill collar at the third coil is 1A when the first coil emits; i is14The axial current of the drill collar at the fourth coil is shown when the axial current of the drill collar is 1A when the first coil is transmitted; i is23The axial current of the drill collar at the third coil is 1A when the second coil transmits; i is24And when the axial current of the drill collar is 1A when the second coil transmits, the axial current of the drill collar at the fourth coil is shown.
5. The resistivity while drilling logging apparent resistivity measurement method as claimed in claim 3 or 4, wherein the specific method of S4 is as follows:
the apparent resistivity R is obtained by the following formulaaL：
Figure FDA0002561115740000023
Wherein, VT2The voltage of the second coil drill collar is shown, and when the voltage of the second coil drill collar is transmitted by the second coil, the axial current generated in the drill collar is1A, the voltage of the drill collar at the second coil; i isM1When the first coil emits, when the axial current of the drill collar is 1A, the current of the electrode is measured; i isM2When the axial current of the drill collar is 1A when the second coil is transmitted, the current of the electrode is measured; a represents a scaling factor of the transmission current of the first coil; b represents a scaling factor of the transmission current of the second coil;
KLcalculating an instrument constant in a linear soft focusing mode through an infinite uniform stratum model with the resistivity Rt:
Figure FDA0002561115740000031
6. a resistivity logging while drilling apparent resistivity measuring method is characterized in that a plurality of azimuth measuring electrodes and a plurality of coils are arranged on a drill collar instrument, the plurality of coils are annularly wound on the drill collar instrument, each coil can transmit and receive current, a focusing position, a first coil, a second coil, a third coil and a fourth coil are preset on the drill collar instrument, one side of the focusing position comprises the first coil and the third coil, and the distance between the first coil and the focusing position is far than that between the first coil and the third coil; the other side is provided with a second coil and a fourth coil, and the second coil is farther away from the focusing position than the fourth coil; the focusing position is a drill collar annular area formed by a third coil and a fourth coil which are adjacent, and the measuring method comprises the following steps:
s1: acquiring axial current of the drill collar at a focusing position when the first coil and the second coil are alternately transmitted;
s2: adjusting the transmitting current of the first coil according to a first scaling factor, and adjusting the transmitting current of the second coil according to a second scaling factor; the axial current of the drill collar at the preset focusing position when the first coil is emitted is equal to the axial current of the drill collar at the preset focusing position when the second coil is emitted, and the axial currents are opposite in direction;
s3: zooming the current flowing out from the focusing position when the first coil is transmitted by a first zooming multiple to obtain a first focusing position current; zooming the current flowing out of the focusing position when the second coil is transmitted by a second zooming multiple to obtain a second focusing position current;
s4: and obtaining apparent resistivity according to the first focusing position current, the second focusing position current and the second coil drill collar voltage, wherein when the second coil drill collar voltage is transmitted by the second coil, the axial current generated in the drill collar is 1A, and the voltage of the drill collar at the second coil is obtained.
7. The resistivity while drilling logging apparent resistivity measurement method as recited in claim 6, wherein the axial current of the drill collar at the focus position is obtained by:
Figure FDA0002561115740000041
Figure FDA0002561115740000042
wherein, I10The axial current of the drill collar at the focusing position when the axial current of the drill collar is 1A during the emission of the first coil is shown; i is20When the second coil is used for transmitting, when the axial current of the drill collar is 1A, the axial current of the drill collar at the focusing position is shown; i is13The axial current of the drill collar at the third coil is 1A when the first coil emits; i is14The axial current of the drill collar at the fourth coil is shown when the axial current of the drill collar is 1A when the first coil is transmitted; i is23The axial current of the drill collar at the third coil is 1A when the second coil transmits; i is24And when the axial current of the drill collar is 1A when the second coil transmits, the axial current of the drill collar at the fourth coil is shown.
8. The method for measuring while-drilling resistivity and logging apparent resistivity as recited in claim 7, wherein the specific method of S4 is as follows:
the apparent resistivity R is obtained by the following formulaaC：
Figure FDA0002561115740000043
Wherein, VT2The voltage of the second coil drill collar is shown, when the voltage of the second coil drill collar is transmitted by the second coil, and the axial current generated in the drill collar is 1A, the voltage of the drill collar at the second coil is shown; i is21When the second coil is used for transmitting, the axial current of the drill collar at the first coil is 1A;
KCthe method is characterized in that the method is an instrument constant in an annular soft focusing mode, and is calculated through an infinite uniform stratum model with the resistivity Rt:
Figure FDA0002561115740000044
9. a computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor when executing the computer program performs the steps of the method of resistivity logging while drilling as described in any one of claims 1 to 8.
10. A computer readable storage medium storing a computer program, wherein the computer program when executed by a processor implements the steps of the method for resistivity logging while drilling as a resistivity measurement method as recited in any one of claims 1 to 8.
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Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1869400A (en) * 2005-05-27 2006-11-29 中国石化集团胜利石油管理局钻井工艺研究院 Double-induction resistivity measuring instrument during drilling
CN201258737Y (en) * 2007-03-28 2009-06-17 普拉德研究及开发股份有限公司 Logging instrument
CN101460868A (en) * 2006-04-07 2009-06-17 贝克休斯公司 Method and apparatus for determining formation resistivity ahead of the bit and azimuthal at the bit
CN101482010A (en) * 2009-02-23 2009-07-15 中国石化集团胜利石油管理局钻井工艺研究院 While-drilling multi-frequency direction induction resistivity survey instrument
CN103821506A (en) * 2014-03-04 2014-05-28 中国石油大学(华东) Three-dimensional array imaging measurement method for resistivity of well surrounding medium
CN104929622A (en) * 2015-06-29 2015-09-23 中国海洋石油总公司 Multi-component while-drilling location electromagnetic wave resistivity imaging instrument
CN105332697A (en) * 2015-12-02 2016-02-17 西安石油大学 Array coplanar coil system for measuring vertical conductivity of stratum
CN105484740A (en) * 2015-12-04 2016-04-13 中国石油天然气集团公司 Multi-frequency detection device for detecting stratum complex resistivity
CN107762497A (en) * 2017-09-20 2018-03-06 中国石油天然气集团公司 One kind is with brill electrode current type al-lateral resistivity logger and method
CN108798656A (en) * 2018-05-30 2018-11-13 中国海洋石油集团有限公司 A kind of method and device for realizing resistivity measurement based on connector for logging while drilling
CN109138995A (en) * 2018-08-13 2019-01-04 中国石油集团工程技术研究院有限公司 When a kind of drilling tool rotates with boring apparent resistivity measuring system and method
CN109488291A (en) * 2018-11-09 2019-03-19 中国海洋石油集团有限公司 A kind of resistivity logging while drilling logging method and measuring device

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1869400A (en) * 2005-05-27 2006-11-29 中国石化集团胜利石油管理局钻井工艺研究院 Double-induction resistivity measuring instrument during drilling
CN101460868A (en) * 2006-04-07 2009-06-17 贝克休斯公司 Method and apparatus for determining formation resistivity ahead of the bit and azimuthal at the bit
CN201258737Y (en) * 2007-03-28 2009-06-17 普拉德研究及开发股份有限公司 Logging instrument
CN101482010A (en) * 2009-02-23 2009-07-15 中国石化集团胜利石油管理局钻井工艺研究院 While-drilling multi-frequency direction induction resistivity survey instrument
CN103821506A (en) * 2014-03-04 2014-05-28 中国石油大学(华东) Three-dimensional array imaging measurement method for resistivity of well surrounding medium
CN104929622A (en) * 2015-06-29 2015-09-23 中国海洋石油总公司 Multi-component while-drilling location electromagnetic wave resistivity imaging instrument
CN105332697A (en) * 2015-12-02 2016-02-17 西安石油大学 Array coplanar coil system for measuring vertical conductivity of stratum
CN105484740A (en) * 2015-12-04 2016-04-13 中国石油天然气集团公司 Multi-frequency detection device for detecting stratum complex resistivity
CN107762497A (en) * 2017-09-20 2018-03-06 中国石油天然气集团公司 One kind is with brill electrode current type al-lateral resistivity logger and method
CN108798656A (en) * 2018-05-30 2018-11-13 中国海洋石油集团有限公司 A kind of method and device for realizing resistivity measurement based on connector for logging while drilling
CN109138995A (en) * 2018-08-13 2019-01-04 中国石油集团工程技术研究院有限公司 When a kind of drilling tool rotates with boring apparent resistivity measuring system and method
CN109488291A (en) * 2018-11-09 2019-03-19 中国海洋石油集团有限公司 A kind of resistivity logging while drilling logging method and measuring device

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