A motion simulation measuring device and method for a resistivity imaging while drilling instrument

Abstract

A motion simulation measuring device and method of a while-drilling resistivity imaging instrument, the device comprises a while-drilling resistivity logging instrument, a horizontal motion mechanism and a rotary motion mechanism, the horizontal motion mechanism drives the while-drilling resistivity logging instrument to move horizontally in a sample container with a sample; the rotary motion mechanism drives the while-drilling resistivity logging instrument to rotate, a data output end of the while-drilling resistivity logging instrument is connected with a data input end of a ground visual system; the measuring method comprises setting motion parameters of the horizontal motion mechanism and the rotary motion mechanism through a PLC controller, starting the while-drilling resistivity logging instrument to collect data, and uploading collected transmitting electrode current data and motion and position information of the while-drilling resistivity logging instrument to a working computer for processing and display, resistivity scanning imaging of a rock model is realized, and thin layer information and azimuth information measurement of a sample equivalent to a formation are completed; the application has the advantages of reasonable structure, simple operation, good flexibility, efficient operation, high imaging resolution and accurate measurement.

Description

Technical Field

[0001] This invention relates to the field of geological steering and reservoir parameter measurement technology for horizontal wells in oil exploration and development, specifically to a motion simulation measurement device and method for a drilling resistivity imaging instrument. Background Technology

[0002] Resistivity logging has become an important technology and method for evaluating oil and gas formations. It allows for qualitative and even quantitative assessment of the oil-bearing potential of formations, providing strong evidence for oil and gas extraction. Logging while drilling requires controlling the drilling direction. If real-time images of the wellbore can be obtained during drilling to identify geological structures such as fractures and pores, geological steering experts can keep the wellbore within high-quality reservoirs. Foreign logging-while-drilling resistivity imaging instruments are already widely used in the market. Energy giants such as Schlumberger, Halliburton, and Baker Hughes have all launched logging-while-drilling resistivity logging tools. Currently, there is a significant demand for logging-while-drilling resistivity in areas such as the Sichuan Basin, Beibu Gulf Basin, and Ordos Basin in China, but this demand is heavily reliant on foreign instruments. Domestic logging-while-drilling resistivity imaging is still in its early stages. In recent years, domestic experts have actively conducted research on logging-while-drilling (LWD) resistivity. Currently, a widely accepted instrument solution is a non-contact coupled lateral resistivity logging instrument. This instrument consists of a measurement and control system and a detector. The measurement and control system includes a transmitter module and a receiver module. The detector mainly consists of a spiral toggle, a button electrode, and a drill collar. The spiral toggle serves as the load circuit of the transmitter module, i.e., the transmitting electrode, used to generate an alternating electromagnetic field. The button electrode, located in the loop formed by the wellbore, formation, and drill collar, serves as the acquisition electrode, used to receive the electromagnetic field signal coupled from the formation. The acquisition electrode is less than 5mm in size, enabling high fracture detection capability. During LWD, the instrument's movement includes axial and circumferential motion. Utilizing this movement, the measurement and control system performs real-time signal acquisition, enabling resistivity scanning imaging.

[0003] Developing logging-while-drilling resistivity imaging instruments to obtain high-resolution formation images is of great significance for studying formation thin-layer information, azimuth information, and formation heterogeneity. Currently, most laboratory devices for evaluating the measurement effectiveness of logging-while-drilling resistivity imaging instruments are static measurements, which cannot quantitatively determine the imaging effect of the instrument. Summary of the Invention

[0004] To address the shortcomings of the existing technology, the present invention aims to provide a motion simulation measurement device and method for a logging-while-drilling (LWD) resistivity imaging instrument. This device simulates the rotation and drilling motion of the wellbore using a logging-while-drilling resistivity instrument. With one acquisition electrode and one transmitting coil, current signals from different orientations are obtained as the LWD resistivity instrument rotates, enabling circumferential and axial scanning of resistivity, thereby achieving LWD resistivity imaging. During dynamic measurement, the imaging of the logging-while-drilling resistivity instrument is quantitatively measured, resulting in high accuracy and efficient operation.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A motion simulation measurement device for a drilling resistivity imaging instrument includes a base 1, a rock sample container 2 disposed in the middle of the base 1, a first load-bearing crossbeam 3-1 and a second load-bearing crossbeam 3-2 respectively disposed on the upper sides of the base 1, a drilling resistivity logging instrument 6 disposed between the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2, a horizontal motion mechanism between the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2 and the base 1 to drive the drilling resistivity logging instrument 6 to move horizontally; a rotary motion mechanism is also disposed between the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2 to drive the drilling resistivity logging instrument 6 to rotate, and the data output terminal of the drilling resistivity logging instrument 6 is connected to the data input terminal of a surface visualization system.

[0007] The horizontal motion mechanism includes rollers 4 at the bottom of the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2. The rollers 4 are movably connected to the moving track 5 at the top of the base 1. The rollers 4 at the bottom of the first load-bearing crossbeam 3-1 serve as driving wheels 4-1, with a roller shaft fixed in the center of the wheel. The power output end of the displacement motor 7 is connected to the power input end of the roller shaft. The rollers 4 at the bottom of the second load-bearing crossbeam 3-2 serve as driven wheels 4-2.

[0008] The rotary motion mechanism includes a rotary motor 8 mounted on the second load-bearing crossbeam 3-2. The power output shaft of the rotary motor 8 is fixedly connected to the center of the large gear 9. The teeth of the large gear 9 are meshed with the teeth of the small gear 11 via a chain 10.

[0009] The logging-while-drilling resistivity tool 6 is equipped with an accelerometer, fluxgate magnetometer, and gyroscope to collect motion and position information. One end of the logging-while-drilling resistivity tool 6 is rotatably connected to the middle of the first load-bearing crossbeam 3-1, and the other end of the logging-while-drilling resistivity tool 6 passes through the rock sample and is connected to one end of the instrument sleeve 12. The other end of the instrument sleeve 12 is fixedly connected to the center of the pinion 11, and the pinion 11 is rotatably connected to the middle of the second load-bearing crossbeam 3-2.

[0010] The ground visualization system includes an instrument power supply module, a data transceiver unit, and a working computer. The drilling resistivity imaging instrument 6, displacement motor 7, and rotary motor 8 are connected to the power supply module via power cables and cable adapters. The data transceiver unit includes a communication cable and a PLC controller. The PLC controller is bidirectionally connected to the motor controllers of displacement motor 7 and rotary motor 8 via the communication cable. The PLC controller is also bidirectionally connected to the working computer for issuing work instructions and uploading data. The data output terminal of the drilling resistivity imaging instrument 6 is connected to the data receiving terminal of the working computer, which analyzes, processes, and displays the real-time uploaded data.

[0011] The power supply cable and communication cable are connected to the conductive slip ring 13 at the top of the instrument sleeve 12. The conductive slip ring 13 leads the power supply cable and communication cable to the power supply module, and the cable does not get tangled when rotated.

[0012] A motion simulation measurement method for a drilling resistivity imaging instrument, comprising the following steps:

[0013] Step 1: Set the parameters of displacement motor 7 and rotary motor 8 through the PLC controller to simulate the axial drilling speed and rotation speed of the drill collar;

[0014] Step 2: Start the logging-while-drilling resistivity logging tool 6 to begin data acquisition, then start the displacement motor 7 and rotary motor 8 to operate; the logging-while-drilling resistivity imaging instrument 6 acquires the current data on the surface of the acquisition electrode of the logging-while-drilling resistivity imaging instrument 6.

[0015] Step 3: The logging-while-drilling resistivity logger 6 uploads the collected electrode current data and the movement and position information of the logging-while-drilling resistivity logger 6 to the working computer via RS485 bus.

[0016] Step 4: The working computer processes and displays the data uploaded in Step 3 using image data acquisition software, performs resistivity scanning imaging on the rock model, and completes the measurement of sample information equivalent to thin-layer information and orientation information of the strata.

[0017] The specific method for step 1 is as follows:

[0018] The parameters of displacement motor 7 and rotary motor 8 are set to simulate the axial drilling speed and rotation speed of the drill collar. The parameters set by the PLC controller include the horizontal displacement speed, rotation speed, horizontal displacement direction, rotation direction, horizontal displacement duration, and rotation duration of the resistivity imaging instrument 6 while drilling.

[0019] The specific method for step 2 is as follows:

[0020] The power supply module supplies power to the drilling resistivity imaging instrument 6. The PLC controller sends a start acquisition command to start the drilling resistivity imaging instrument 6 to start acquiring data, and then starts the motor to run. The drilling resistivity imaging instrument 6 acquires the current data on the surface of the acquisition electrode of the drilling resistivity imaging instrument 6.

[0021] The collected electrode current data of the logging-while-drilling resistivity tool 6 is collected every T time interval, where T is the sampling period, and satisfies the following relationship:

[0022]

[0023] Where v is the rotational speed of the logging-while-drilling resistivity log (LWR) tool, and N min The minimum number of sampling points is related to the radius r and electrode diameter d of the logging-while-drilling resistivity tool, as shown in the following formula:

[0024]

[0025] The specific method for step 4 is as follows:

[0026] In the image data acquisition software on the work computer, the resistivity of the formation is calculated based on the current data acquired in step 2, using the following formula:

[0027]

[0028] In the formula, R is the formation resistivity in Ω·m; V is the emission voltage on the transmitting electrode; I is the acquisition current of the acquisition electrode; K is the instrument constant; the current signals measured by the logging-while-drilling resistivity tool 6 at different azimuths from 0° to 360° are organized into a two-dimensional matrix, the two-dimensional matrix is ​​converted into pixels and displayed to present the inner wall resistivity scanning imaging results of the rock sample; the horizontal axis represents different azimuths, and the vertical axis represents the image display results of the measurement results.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] 1. This invention simulates the working state of the downhole resistivity logging tool 6 through a horizontal motion mechanism and a rotary motion mechanism. The speed and direction of displacement are set by a PLC controller to simulate the drilling state of the downhole resistivity logging tool 6, and the speed and direction of rotation are set to simulate the rotation state of the downhole resistivity logging tool 6. The two motion modes can be performed simultaneously or separately. The device has a reasonable structure, good flexibility, and is convenient for measurement.

[0031] 2. The logging-while-drilling resistivity tool 6 can acquire current signals from different orientations as it rotates, with only one acquisition electrode, to achieve circumferential and axial scanning of resistivity, thereby realizing imaging of the resistivity while drilling. During dynamic measurement, the imaging of the logging-while-drilling resistivity tool 6 is quantitatively judged, with high accuracy and high operating efficiency.

[0032] 3. The displacement motor and rotary motor are controlled by the data transceiver unit through the ground visualization system, and the data measured by the logging-while-drilling resistivity tool 6 are analyzed, processed and displayed in real time, and work instructions are issued; current value data is collected every T time period to ensure imaging effect and improve measurement accuracy.

[0033] In summary, this invention simulates the working state of a downhole resistivity logging tool through horizontal and rotary motion mechanisms. These two motion modes can be performed simultaneously or independently. The device has a reasonable structure, good flexibility, and convenient measurement. With a single acquisition electrode, it acquires current signals from different orientations as the logging tool rotates, achieving imaging of the scanning resistivity. A ground visualization system controls the displacement and rotary motors via a data transceiver unit, and analyzes, processes, and displays the data measured by the logging tool in real time. The system is highly efficient and has high measurement accuracy. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of a downhole measurement device simulated by a drilling resistivity imaging instrument provided in an embodiment of the present invention.

[0035] Figure 2 This is a schematic diagram of the transmission mechanism of the rotary motion component according to an embodiment of the present invention.

[0036] Figure 3 This is a schematic diagram of the instrument connection device for the rotary motion component according to an embodiment of the present invention.

[0037] Figure 4 This is a block diagram of an instrument measurement and control system according to an embodiment of the present invention.

[0038] Figure 5 This is an artificial rock sample model according to an embodiment of the present invention.

[0039] Figure 6 This is a flowchart of a measurement method according to an embodiment of the present invention. Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings.

[0041] See Figures 1 to 3A motion simulation measurement device for a drilling resistivity imaging instrument includes a base 1, a rock sample container 2 disposed in the middle of the base 1, a first load-bearing crossbeam 3-1 and a second load-bearing crossbeam 3-2 respectively disposed on the upper two sides of the base 1, a drilling resistivity logging instrument 6 disposed between the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2, a horizontal motion mechanism between the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2 and the base 1 to drive the drilling resistivity logging instrument 6 to move horizontally; a rotary motion mechanism is also disposed between the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2 to drive the drilling resistivity logging instrument 6 to rotate, and the data output terminal of the drilling resistivity logging instrument 6 is connected to the data input terminal of the ground visualization system.

[0042] The horizontal motion mechanism includes rollers 4 at the bottom of the first load-bearing crossbeam 3-1 and the second load-bearing crossbeam 3-2. The rollers 4 are movably connected to the moving track 5 at the top of the base 1. The rollers 4 at the bottom of the first load-bearing crossbeam 3-1 serve as driving wheels 4-1, with a roller shaft fixed in the center of the wheel. The power output end of the displacement motor 7 is connected to the power input end of the roller shaft. The rollers 4 at the bottom of the second load-bearing crossbeam 3-2 serve as driven wheels 4-2.

[0043] The rotary motion mechanism includes a rotary motor 8 mounted on the second load-bearing crossbeam 3-2. The power output shaft of the rotary motor 8 is fixedly connected to the center of the large gear 9. The teeth of the large gear 9 are meshed with the teeth of the small gear 11 via a chain 10.

[0044] One end of the logging-while-drilling resistivity instrument 6 is rotatably connected to the middle of the first load-bearing crossbeam 3-1, and the other end of the logging-while-drilling resistivity instrument 6 passes through the rock sample and is connected to one end of the instrument sleeve 12. The other end of the instrument sleeve 12 is fixedly connected to the center of the pinion 11, and the pinion 11 is rotatably connected to the middle of the second load-bearing crossbeam 3-2.

[0045] See Figure 4 The accelerometer, fluxgate, and gyroscope integrated into the logging-while-drilling resistivity tool 6 collect motion and position information of the logging-while-drilling resistivity tool 6.

[0046] The ground visualization system includes an instrument power supply module, a data transceiver unit, and a working computer. The drilling resistivity imaging instrument 6, displacement motor 7, and rotary motor 8 are connected to the power supply module via power cables and cable adapters. The data transceiver unit includes a communication cable and a PLC controller. The PLC controller is bidirectionally connected to the motor controllers of displacement motor 7 and rotary motor 8 via the communication cable. The PLC controller is also bidirectionally connected to the working computer for issuing work instructions and uploading data. The data output terminal of the drilling resistivity imaging instrument 6 is connected to the data receiving terminal of the working computer, which analyzes, processes, and displays the real-time uploaded data.

[0047] The power supply cable and communication cable are connected to the conductive slip ring 13 at the top of the instrument sleeve 12. The conductive slip ring 13 leads the power supply cable and communication cable to the power supply module, and finally the uniform rotation of the logging instrument is achieved by the motor drive, and the cable does not get tangled with the rotation.

[0048] The rock sample container is a non-metallic container, and the container contains an aqueous solution simulating the mineralization of mud.

[0049] See Figure 6 A motion simulation measurement method for a drilling resistivity imaging instrument, comprising the following steps:

[0050] Step 1: Set the parameters of displacement motor 7 and rotary motor 8 through the PLC controller to simulate the axial drilling speed and rotation speed of the drill collar;

[0051] The parameters of displacement motor 7 and rotary motor 8 are set to simulate the axial drilling speed and rotation speed of the drill collar. The parameters set by the PLC controller include the horizontal displacement speed, rotation speed, horizontal displacement direction, rotation direction, horizontal displacement duration, and rotation duration of the resistivity imaging instrument 6 while drilling.

[0052] This includes the horizontal displacement velocity of the Drilling Resistivity Imaging Instrument 6, the rotational speed of the Drilling Resistivity Imaging Instrument 6, the direction of horizontal displacement, the turning direction of the Drilling Resistivity Imaging Instrument 6, the duration of horizontal displacement, and the rotational duration of the Drilling Resistivity Imaging Instrument 6.

[0053] Step 2: Start the logging-while-drilling resistivity tool 6 to begin data acquisition, and start the displacement motor 7 and rotary motor 8 to operate; specifically:

[0054] The power supply module supplies power to the drilling resistivity imaging instrument 6, starts the drilling resistivity logging instrument 6 to start collecting data, and then starts the displacement motor 7 and the rotary motor 8 to run; the drilling resistivity imaging instrument 6 collects the current data on the surface of the acquisition electrode of the drilling resistivity imaging instrument 6.

[0055] The electrode current data collected by the logging-while-drilling resistivity logging tool 6 in step 2 is collected every T time interval, where T is the sampling period, and satisfies the following relationship:

[0056]

[0057] Where v is the rotational speed of the logging-while-drilling resistivity log (LWR) tool, and N min The minimum number of sampling points is related to the radius r and electrode diameter d of the logging-while-drilling resistivity tool, as shown in the following formula:

[0058]

[0059] Step 3: The logging-while-drilling resistivity logger 6 uploads the collected electrode current data and the movement and position information of the logging-while-drilling resistivity logger 6 to the working computer via RS485 bus.

[0060] Step 4: The working computer processes and displays the data uploaded in Step 3 using image data acquisition software, performs resistivity scanning imaging on the rock model, and completes the measurement of sample information equivalent to thin-layer information and orientation information of the strata.

[0061] In the image data acquisition software on the work computer, the resistivity of the formation is calculated based on the current data acquired in step 2, using the following formula:

[0062]

[0063] In the formula, R is the formation resistivity in Ω·m; V is the emission voltage on the transmitting electrode; I is the acquisition current of the acquisition electrode; K is the instrument constant; the current signals measured by the logging-while-drilling resistivity tool 6 at different azimuths from 0° to 360° are organized into a two-dimensional matrix, the two-dimensional matrix is ​​converted into pixels and displayed to present the inner wall resistivity scanning imaging results of the rock sample; the horizontal axis represents different azimuths, and the vertical axis represents the image display results of the measurement results.

[0064] Figure 5 This is an artificial rock sample model. In this embodiment, an artificial crack is designed, that is, the cube-shaped rock sample is divided into two by a cutting method. At the same time, a through hole with a diameter equivalent to that of the detector is designed. In addition, the rock sample is placed in a plastic container, and an aqueous solution with a certain degree of mineralization is added to the container, with the solution level at least close to the through hole.

Claims

1. A motion simulation measurement device for a drilling resistivity imaging instrument, comprising a base (1), wherein a rock sample container (2) is disposed in the middle of the base (1), characterized in that: The base (1) is provided with a first load-bearing crossbeam (3-1) and a second load-bearing crossbeam (3-2) on both sides above it. A logging-while-drilling resistivity instrument (6) is provided between the first load-bearing crossbeam (3-1) and the second load-bearing crossbeam (3-2). A horizontal motion mechanism is provided between the first load-bearing crossbeam (3-1) and the second load-bearing crossbeam (3-2) and the base (1) to drive the logging-while-drilling resistivity instrument (6) to move horizontally. A rotary motion mechanism is also provided between the first load-bearing crossbeam (3-1) and the second load-bearing crossbeam (3-2) to drive the logging-while-drilling resistivity instrument (6) to rotate. The data output terminal of the logging-while-drilling resistivity instrument (6) is connected to the data input terminal of the ground visualization system. The horizontal motion mechanism includes a first load-bearing crossbeam (3-1) and a roller (4) at the bottom of the second load-bearing crossbeam (3-2). The roller (4) is movably connected to the moving track (5) at the top of the base (1). The roller (4) at the bottom of the first load-bearing crossbeam (3-1) serves as the driving wheel (4-1). A roller shaft is fixed in the center of the wheel. The power output end of the displacement motor (7) is connected to the power input end of the roller shaft. The roller (4) at the bottom of the second load-bearing crossbeam (3-2) serves as the driven wheel (4-2). The rotary motion mechanism includes a rotary motor (8) mounted on the second load-bearing crossbeam (3-2). The power output shaft of the rotary motor (8) is fixedly connected to the wheel center of the large gear (9). The teeth of the large gear (9) are meshed with the teeth of the small gear (11) through a chain (10). The accelerometer, fluxgate, and gyroscope of the logging-while-drilling resistivity instrument (6) are used to collect motion and position information of the logging-while-drilling resistivity instrument (6); one end of the logging-while-drilling resistivity instrument (6) is rotatably connected to the middle of the first load-bearing crossbeam (3-1), and the other end of the logging-while-drilling resistivity instrument (6) passes through the rock sample and is connected to one end of the instrument sleeve (12). The other end of the instrument sleeve (12) is fixedly connected to the center of the pinion (11), and the pinion (11) is rotatably connected to the middle of the second load-bearing crossbeam (3-2). The ground visualization system includes an instrument power supply module, a data transceiver unit, and a working computer; the drilling resistivity imaging instrument (6), displacement motor (7), and rotary motor (8) to be measured are connected to the power supply module via power supply cables and cable adapters; the power supply cables and communication cables are connected to the conductive slip ring (13) at the top of the instrument sleeve (12), and the conductive slip ring (13) leads the power supply cables and communication cables to the power supply module, and the cables do not get tangled as they rotate; The logging-while-drilling resistivity logging tool (6) is configured to collect current data on the surface of its collecting electrode, and the data is collected once every T time interval, where T is the sampling period, and the following relationship is satisfied: in, The rotational speed of the logging-while-drilling resistivity logging tool (6) is... To minimize the number of sampling points, the minimum number of sampling points is related to the radius of the logging-while-drilling resistivity tool (6). and electrode diameter The relevant formula is as follows: 。 2. The motion simulation measurement device for a drilling resistivity imaging instrument according to claim 1, characterized in that: The data transceiver unit includes a communication cable and a PLC controller. The PLC controller is bidirectionally connected to the motor controller of the displacement motor (7) and the motor controller of the rotary motor (8) via the communication cable. The PLC controller is also bidirectionally connected to the working computer for issuing work instructions and uploading data. The data output terminal of the drilling resistivity imaging instrument (6) is connected to the data receiving terminal of the working computer. The working computer analyzes, processes and displays the data uploaded in real time.

3. A motion simulation measurement method for a drilling resistivity imaging instrument, based on the device described in claim 1 or 2, characterized in that: The specific steps include: Step 1: Set the parameters of the displacement motor (7) and the rotary motor (8) through the PLC controller to simulate the axial drilling speed and rotation speed of the drill collar; Step 2: Start the logging-while-drilling resistivity logging tool (6) to start collecting data, then start the displacement motor (7) and the rotary motor (8) to run; the logging-while-drilling resistivity imaging instrument (6) collects the current data on the surface of the acquisition electrode of the logging-while-drilling resistivity imaging instrument (6); Step 3: The logging-while-drilling resistivity logger (6) uploads the collected electrode current data and the movement and position information of the logging-while-drilling resistivity logger (6) to the working computer via RS485 bus. Step 4: The working computer processes and displays the data uploaded in Step 3 using image data acquisition software, performs resistivity scanning imaging on the rock model, and completes the measurement of sample information equivalent to thin-layer information and orientation information of the strata.

4. The motion simulation measurement method for a drilling resistivity imaging instrument according to claim 3, characterized in that: The specific method for step 1 is as follows: The parameters of the displacement motor (7) and the rotary motor (8) are set to simulate the axial drilling speed and rotation speed of the drill collar. The parameters set by the PLC controller include the horizontal displacement speed of the resistivity imaging instrument (6), the rotation speed of the resistivity imaging instrument (6), the horizontal displacement direction, the rotation direction of the resistivity imaging instrument (6), the horizontal displacement duration, and the rotation duration of the resistivity imaging instrument (6).

5. The motion simulation measurement method for a drilling resistivity imaging instrument according to claim 3, characterized in that: The specific method for step 2 is as follows: The power supply module supplies power to the drilling resistivity imaging instrument (6). The PLC controller sends a start acquisition command to start the drilling resistivity imaging instrument (6) to start acquiring data, and then starts the motor to run. The drilling resistivity imaging instrument (6) acquires the current data on the surface of the acquisition electrode of the drilling resistivity imaging instrument (6). The collected electrode current data of the logging-while-drilling resistivity tool (6) is obtained by using a method that... Data is collected once per time period. The sampling period is defined as follows, and the following relationship is satisfied: in, The rotational speed of the logging-while-drilling resistivity logging tool (6) is... To minimize the number of sampling points, the minimum number of sampling points is related to the radius of the logging-while-drilling resistivity tool (6). and electrode diameter The relevant formula is as follows: 。 6. The motion simulation measurement method for a drilling resistivity imaging instrument according to claim 5, characterized in that: The specific method for step 4 is as follows: In the image data acquisition software on the work computer, the resistivity of the formation is calculated based on the current data acquired in step 2, using the following formula: In the formula, R is the formation resistivity, with units of... V is the emission voltage on the emission electrode; I is the acquisition current of the acquisition electrode; K is the instrument constant; The current signals measured by the logging-while-drilling resistivity instrument (6) at different azimuths from 0° to 360° are organized into a two-dimensional matrix, the two-dimensional matrix is ​​converted into pixels, and displayed to present the inner wall resistivity scanning imaging results of the rock sample. The horizontal axis represents different orientations, and the vertical axis represents the image display results of the measurement results.

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