Calibration device and method for lateral imaging resistivity instrument while drilling

Abstract

The present invention provides a calibration device for a lateral imaging resistivity instrument while drilling, the device comprising: a port, which comprises a transmitting electrode positive port, a transmitting electrode negative port and a receiving electrode port, which are respectively connected to the transmitting electrode positive electrode, the transmitting electrode negative electrode and the receiving electrode arranged on a drill collar in a one-to-one correspondence; a formation environment simulation module, which comprises a first formation unit and a second formation unit, the first end of the first formation unit is connected to the transmitting electrode negative port, and the first end of the second formation unit is connected to the receiving electrode port; an annular drilling fluid simulation module, the first end of which is connected to the transmitting electrode positive port, and the second end is connected to the second end of the first formation unit and the second end of the second formation unit. The present invention can realize the rapid calibration of the lateral imaging resistivity instrument while drilling, the device is compact and portable, and the flexibility is improved.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas exploration and development, and in particular to a device and method for calibrating a while-drilling lateral imaging resistivity instrument. Background Art

[0002] Measurement while drilling / logging technology is an important means to identify complex oil and gas reservoirs such as fractures, thin layers, low porosity and low permeability in the development of highly deviated wells and horizontal wells. Among them, the resistivity measurement while drilling instrument measures the resistivity / conductivity of the formation near the wellbore, and uses the resistivity difference of the formation to identify and divide different oil, gas and water layers. The data can be uploaded to the surface during the drilling process to help drillers optimize and adjust the trajectory and help geologists calculate oil and gas reserves and production.

[0003] Conventional LWD lateral resistivity logging instruments measure a curve of formation parameter properties versus depth to reflect formation information, and the information measured at each point is the macroscopic response at that location. The design of LWD imaging logging instruments takes into account the complexity and heterogeneity of the formation, and uses sensor array scanning or rotational scanning to collect a large amount of formation information along the borehole longitudinally, radially or circumferentially. After transmitting it to the wellbore, image processing technology is used to obtain a two-dimensional image of the well wall or a three-dimensional image within a certain detection depth around the borehole.

[0004] In the prior art, a typical lateral resistivity while drilling tool comprises a transmitting electrode and a receiving electrode.

[0005] The transmitting electrode on the drill collar transmits current into the formation, and then the current returns from the receiving electrode to form a measurement loop. The current change measured on the receiving electrode can reflect the resistivity change of the formation. Both the transmitting electrode and the receiving electrode can be arranged in an array to obtain measurement curves at different depths or images with azimuth recognition capabilities.

[0006] The instrument measures electronic signals. During the research and development or workshop inspection process, it is necessary to establish a correlation between the electronic signals and the formation resistivity, which is called instrument calibration or calibration. One method is to use a large physical model, using real rocks and wellbore fluids, serially changing their electrical properties to obtain the numerical relationship between the two. Due to the large size of the instrument, this method is cumbersome to operate and has high costs, so a quick and simplified calibration method and device is needed.

[0007] Therefore, the present invention provides a device and method for calibrating a lateral imaging resistivity instrument while drilling. Summary of the invention

[0008] In order to solve the above problems, the present invention provides a calibration device for a lateral imaging resistivity instrument while drilling, the device comprising:

[0009] Ports, including a transmitting electrode positive port, a transmitting electrode negative port and a receiving electrode port, which are respectively connected to the transmitting electrode positive electrode, the transmitting electrode negative electrode and the receiving electrode arranged on the drill collar in a one-to-one correspondence;

[0010] A formation environment simulation module, comprising a first formation unit and a second formation unit, wherein a first end of the first formation unit is connected to the negative port of the transmitting electrode, and a first end of the second formation unit is connected to the receiving electrode port;

[0011] An annular drilling fluid simulation module has a first end connected to the positive port of the transmitting electrode, and a second end connected to the second end of the first formation unit and the second end of the second formation unit.

[0012] According to an embodiment of the present invention, the transmitting electrode positive port includes a first positive port and a second positive port, and the transmitting electrode negative port includes a first negative port and a second negative port.

[0013] According to one embodiment of the present invention, the first formation unit includes: a first simulation unit and a second simulation unit, the first end of the first simulation unit is connected to the first negative port, and the first end of the second simulation unit is connected to the second negative port.

[0014] According to one embodiment of the present invention, the second formation unit includes a third simulation unit, and a first end of the third simulation unit is connected to the receiving electrode port.

[0015] According to one embodiment of the present invention, the annular drilling fluid simulation module includes: a fourth simulation unit and a fifth simulation unit, the first end of the fourth simulation unit is connected to the first positive port, and the first end of the fifth simulation unit is connected to the second positive port.

[0016] According to an embodiment of the present invention, the second end of the first analog unit, the second end of the second analog unit, the second end of the third analog unit, the second end of the fourth analog unit and the second end of the fifth analog unit are connected to each other.

[0017] According to one embodiment of the present invention, the device further comprises:

[0018] A gear switching device has a first end connected to the port and a second end connected to the formation environment simulation module and the annular drilling fluid simulation module.

[0019] According to an embodiment of the present invention, the gear switching device includes a plurality of gears, and each gear corresponds to two connection ends, which are respectively connected to the negative port of the transmitting electrode and the positive port of the transmitting electrode.

[0020] According to an embodiment of the present invention, the number of the gear switching devices is the same as the number of the transmitting electrodes, and the multiple gear switching devices are controlled in a linkage arrangement.

[0021] According to another aspect of the present invention, a method for calibrating a lateral imaging resistivity instrument while drilling is provided. The instrument calibration process is performed by using the device as described in any one of the above items. The method comprises the following steps:

[0022] linearly or logarithmically changing the resistivity of the calibration instrument and recording corresponding measurement data;

[0023] Fitting the measured data to establish a relationship between the known resistivity of the calibration device and the measured data;

[0024] Based on the relationship, a calibration relationship and an instrument scale factor are obtained.

[0025] The device and method for calibrating a lateral imaging resistivity instrument while drilling provided by the present invention connect the port of the calibration device to the electrode according to the current loop relationship between the transmitting electrode and the receiving electrode and the formation, and simulate the electrical environment of the formation where the downhole instrument is located on the ground, so that the contribution value of the formation and mud resistivity around the instrument can be flexibly changed, and the function verification test of the lateral imaging resistivity instrument while drilling and the calibration of the relationship between the instrument measurement signal and the formation resistivity can be realized in a workshop or a drilling site, so that the rapid calibration of the lateral imaging resistivity instrument while drilling can be realized, and the device is compact and portable, which improves the flexibility.

[0026] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0028] Figure 1 A structural block diagram of a calibration device for a lateral imaging resistivity tool while drilling according to an embodiment of the present invention is shown;

[0029] Figure 2 A structural block diagram of a calibration device for a lateral imaging resistivity tool while drilling according to another embodiment of the present invention is shown;

[0030] Figure 3 A schematic diagram of the resistivity measurement principle of lateral imaging while drilling according to an embodiment of the present invention is shown;

[0031] Figure 4 A schematic diagram showing a connection method of a calibration device according to an embodiment of the present invention is shown;

[0032] Figure 5 A schematic diagram of a resistor network of a calibration device according to an embodiment of the present invention is shown;

[0033] Figure 6 A schematic diagram showing the adjustment principle of the analog unit according to an embodiment of the present invention is shown;

[0034] Figure 7 A flow chart of a method for calibrating a lateral imaging resistivity tool while drilling according to an embodiment of the present invention is shown; and

[0035] Figure 8 A flow chart of a calibration method for a lateral imaging resistivity tool while drilling according to another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0037] Figure 1 The structure block diagram of a calibration device for a lateral imaging resistivity tool while drilling according to an embodiment of the present invention is shown.

[0038] like Figure 1 The calibration device 100 includes a port 101, a formation environment simulation module 102 and an annulus drilling fluid simulation module 103; wherein the port 101 includes a transmitting electrode positive port 1012, a transmitting electrode negative port 1011 and a receiving electrode port 1013; the formation environment simulation module 102 includes a first formation unit 1021 and a second formation unit 1022.

[0039] The port 101 comprises a transmitting electrode positive port 1012 , a transmitting electrode negative port 1011 and a receiving electrode port 1013 , which are respectively connected to the transmitting electrode positive electrode, the transmitting electrode negative electrode and the receiving electrode arranged on the drill collar in a one-to-one correspondence.

[0040] The formation environment simulation module 102 includes a first formation unit 1021 and a second formation unit 1022 . The first end of the first formation unit 1021 is connected to the transmitting electrode negative port 1011 , and the first end of the second formation unit 1022 is connected to the receiving electrode port 1013 .

[0041] The first end of the annular drilling fluid simulation module 103 is connected to the transmitting electrode positive port 1012 , and the second end is connected to the second end of the first formation unit 1021 and the second end of the second formation unit 1022 .

[0042] Furthermore, if Figure 2 As shown, the emitter electrode positive port 1012 includes a first positive port 207 and a second positive port 208 , and the emitter electrode negative port 1011 includes a first negative port 206 and a second negative port 209 .

[0043] Furthermore, if Figure 2 As shown, the first formation unit 1021 includes: a first simulation unit 201 and a second simulation unit 202 , the first end of the first simulation unit 201 is connected to the first negative port 206 , and the first end of the second simulation unit 202 is connected to the second negative port 209 .

[0044] Furthermore, if Figure 2 As shown, the second formation unit 2022 includes a third simulation unit 203 , and a first end of the third simulation unit 203 is connected to the receiving electrode port 1013 .

[0045] Furthermore, if Figure 2 As shown, the annular drilling fluid simulation module 103 includes: a fourth simulation unit 204 and a fifth simulation unit 205 . The first end of the fourth simulation unit 204 is connected to the first positive port 207 , and the first end of the fifth simulation unit 205 is connected to the second positive port 208 .

[0046] Furthermore, if Figure 2 As shown, the second end of the first simulation unit 201, the second end of the second simulation unit 202, the second end of the third simulation unit 203, the second end of the fourth simulation unit 204 and the second end of the fifth simulation unit 205 are connected to each other.

[0047] In one embodiment, the device further comprises:

[0048] The gear switching device has a first end connected to the port 101 , and a second end connected to the formation environment simulation module 102 and the annular drilling fluid simulation module 103 .

[0049] In one embodiment, the gear switching device includes a plurality of gears, and each gear corresponds to two connection terminals, which are respectively connected to the negative port 1011 of the transmitting electrode and the positive port 1012 of the transmitting electrode.

[0050] In one embodiment, the number of gear switching devices is the same as the number of transmitting electrodes, and the multiple gear switching devices are controlled in a linkage arrangement.

[0051] Figure 3 A schematic diagram of the resistivity measurement principle of lateral imaging while drilling according to an embodiment of the present invention is shown. Figure 3 A basic measurement structure is shown in FIG. 1 , which includes two transmitting electrodes and one receiving (measuring) electrode. The receiving electrode may be a lateral electrode or an imaging electrode.

[0052] Two transmitting electrodes are placed on the upper and lower (or left and right) sides of the drill collar, and a positive and negative potential difference is applied to the drill collar and the two ends of the electrode. The signals emitted by the two transmitting electrodes are in opposite phases, so that the potential generated on the drill collar is also opposite, such as Figure 3 The two ends of the drill collar shown, that is, the outer sides of the two emitting electrodes are negative electrodes -, and the inner sides of the two emitting electrodes are positive electrodes +. Therefore, inside the two emitting electrodes, the current flows relatively inwards and flows outwards from the center of the emitting electrodes.

[0053] The receiving (measuring) electrode is located at the center of the transmitting electrode and can be divided into lateral electrodes and imaging electrodes according to their functions. The lateral electrode measures the current signal on the entire drill collar and has no directionality, but the signal-to-noise ratio is higher; the imaging electrode can be understood as a part of the lateral electrode and can have orientation, but due to its small area, the signal-to-noise ratio is lower than that of the lateral electrode at the same current density. Figure 3 The electrode imaged in the figure is circular, but is not limited to this shape in practice.

[0054] The current lateral working mode is adopted to obtain the apparent resistivity of the formation. The electric field model is as follows Figure 3 As shown in the figure, in the transmission mode, the main current is emitted from A0, flows into the formation through the shielding electrodes A1 and A1', and returns to B and B' to form the measurement. After the current flows out of the measuring electrode, it first passes through the annular drilling fluid (usually low resistivity) into the formation, and then passes through the annular drilling fluid back to the instrument to form a loop.

[0055] Figure 4 A schematic diagram of a connection method of a calibration device according to an embodiment of the present invention is shown.

[0056] Figure 4 The left box in the middle is a schematic diagram of the calibration device port connection. In order to simulate the resistivity of the formation, it will be equipped with 5 ports (only for Figure 3 Model, the specific situation can be adjusted according to the number of transmitting and receiving electrodes), connect the port with the electrode position corresponding to the metal drill collar according to the port identification (electrical conduction), so as to simulate the electrical environment of the underground wellbore, annulus drilling fluid and formation.

[0057] Figure 5 A schematic diagram of a resistor network of a calibration device according to an embodiment of the present invention is shown.

[0058] Figure 5 The diagram shows the network structure of the simulation unit of the calibration device and the connection method with each electrode when in use. The simulation unit includes a first simulation unit, a second simulation unit, a third simulation unit, a fourth simulation unit and a fifth simulation unit. Figure 5In the embodiment, the first analog unit adopts the resistor Rf1, the second analog unit adopts the resistor Rf2, the third analog unit adopts the resistor Rf0, the fourth analog unit adopts the resistor Rm1, and the fifth analog unit adopts the resistor Rm2.

[0059] Among them, Rf0, Rf1 and Rf2 simulate the resistance of the path of the measured current through the formation, Rf0 and Rf1 are connected in series to form one loop, and Rf0 and Rf2 are connected in series to form another loop. Rm1 and Rm2 simulate the resistivity of the path of the measured current through the annular drilling fluid.

[0060] according to Figure 3 It can be seen that the formation and the annular drilling fluid are not simply connected in series or in parallel in the circuit model. Therefore, the formation contribution is divided into three parts in the calibration device. One part Rf0 is connected in parallel with the drilling fluid contribution Rm1 and Rm2, and the other two parts Rf1 and Rf2 are connected in series with the total contribution of the former (Rf0, Rm1 and Rm).

[0061] like Figure 5 As shown, considering the series-parallel relationship among Rf0, Rf1, Rf2, Rm1, and Rm2, when simulating the wellbore electrical environment, the resistivity contribution value of a certain formation needs to comprehensively consider the relationship between several of them. For example, to simulate a formation resistivity of 1Ω.m, Rf0, Rf1, Rf2, Rm1, and Rm2 need to be changed at the same time.

[0062] Therefore, a resistor network adjustment device based on a linkage switch is disclosed, such as Figure 6 As shown in the figure, 5 groups of gears are set. When the switch is in gear 1, it corresponds to a group of Rf0, Rf1, Rf2, Rm1, and Rm2 values; when the switch is in gear 2, it corresponds to another group of Rf0, Rf1, Rf2, Rm1, and Rm2 values. At the same time, Rf0, Rf1, Rf2, Rm1, and Rm2 devices use low-temperature drift resistor devices to eliminate the influence of temperature on resistance.

[0063] Figure 6 A schematic diagram of the analog unit adjustment principle according to an embodiment of the present invention is shown.

[0064] like Figure 6 As shown, the simulated formation circuit network between port B (negative port of the first transmitting electrode) and port A1 (positive port of the first transmitting electrode) is controlled by linkage device 1, contacts 1-6 are connected to port B, contacts 7-12 are connected to port A1, and 6 groups of formation resistance value simulations can be realized. Port A0 (receiving electrode port), port A1' (positive port of the second transmitting electrode) and port B' (negative port of the second transmitting electrode) are also connected to the simulated resistance network ( Figure 6(not shown), synchronous control can be achieved through the linkage device, that is, synchronous control of linkage device 1 and linkage device 2.

[0065] Specifically, the multiple gear switching devices are implemented by linkage device 1, linkage device 2, ... linkage device n. The number of gear switching devices is the same as the number of transmitting electrodes, and the multiple gear switching devices are controlled in a linkage setting manner.

[0066] The gear switching device may include multiple gears. Figure 6 The gear switching device shown in includes 6 gears, and each gear corresponds to a group of simulation units (ie, including the first simulation unit to the fifth simulation unit).

[0067] like Figure 6 The analog units corresponding to the second gear are R1, R2, R3, R4, R4' and R5, that is, the first analog unit uses resistor R1, the second analog unit uses resistor R5, the third analog unit uses resistor R3, the fourth analog unit uses resistor R2, and the fifth analog unit uses resistor R4 and resistor R4' in parallel.

[0068] By analogy, the analog units corresponding to the third gear are R6, R7, R8, R9, R9' and R10, that is, the first analog unit uses resistor R6, the second analog unit uses resistor R10, the third analog unit uses resistor R8, the fourth analog unit uses resistor R7, and the fifth analog unit uses resistor R9 and resistor R9' in parallel.

[0069] By analogy, the analog units corresponding to the fourth gear are R11, R12, R13, R14, R14' and R15, that is, the first analog unit uses resistor R11, the second analog unit uses resistor R15, the third analog unit uses resistor R13, the fourth analog unit uses resistor R12, and the fifth analog unit uses resistor R14 and resistor R14' in parallel.

[0070] It should be clarified that the setting method of the simulation unit of gears five to six is ​​the same as that of gears two, three and four, and the present invention will not be repeated here.

[0071] For example, when the linkage device 1 is in gear position 1, that is, contact 1 is connected to port B, and contact 7 is connected to port A1. At this time, there is no formation simulation resistance (i.e., infinite) between port B and port A1, port A0 is also connected to no formation simulation resistance (infinite), and the formation simulation resistance between port B' and port A' is also infinite. At this time, the simulation is the no-load measurement state when the instrument measurement circuit is open.

[0072] For example, when the linkage device 1 is in gear position 2, that is, contact 2 is connected to port B, and contact 8 is connected to port A1. At this time, the formation simulation resistance between port B and port A1 is R1 and R2 in series, the formation simulation resistance connected to port A0 is R3, and the formation simulation resistance between port B' and port A1' is R4 and R4' in parallel and then connected in series with R5.

[0073] For example, when the linkage device 1 is in gear position 3, that is, contact 3 is connected to port B, and contact 9 is connected to port A1. At this time, the formation simulation resistance between port B and port A1 is R6 and R7 in series, the formation simulation resistance connected to port A0 is R8, and the formation simulation resistance between port B' and port A1' is R9 and R9' in parallel and then connected in series with R10.

[0074] For example, when the linkage device 1 is in gear position 4, that is, at this time, contact 4 is connected to port B, and contact 10 is connected to port A1. At this time, the formation simulation resistance between port B and port A1 is R11 and R12 in series, the formation simulation resistance connected to port A0 is R13, and the formation simulation resistance between port B' and port A1' is R14 and R14' in parallel and then connected in series with R15.

[0075] It should be clear that the connection method from gear position 5 to gear position 6 is the same as that of gear position 2, gear position 3 and gear position 4, and the present invention will not be described in detail here.

[0076] By analogy, through the linkage device (including linkage device 1 and linkage device 2) and the resistance simulation network (i.e., multiple groups of simulation units), at least 6 groups of formation resistance value simulations can be realized, thereby being closer to the resistivity environmental simulation test and calibration under different formation conditions.

[0077] Figure 7 The flow chart of the calibration method of the lateral imaging resistivity instrument while drilling according to one embodiment of the present invention is shown. The instrument calibration process is performed by the calibration device as described in any one of the above items, specifically, comprising the following steps:

[0078] like Figure 7 , in step S701, the resistivity of the calibration instrument is linearly or logarithmically changed, and the corresponding measurement data is recorded.

[0079] like Figure 7 In step S702, the measured data is fitted to establish a relationship between the known resistivity of the calibration device and the measured data.

[0080] like Figure 7 In step S703, the calibration relationship and instrument scale factor are obtained based on the relationship.

[0081] Figure 8A flow chart of a calibration method for a lateral imaging resistivity tool while drilling according to another embodiment of the present invention is shown.

[0082] (1) Set the instrument (simulating the transmitting electrode and receiving electrode set on the drill collar, such as Figure 4 The right part shown in the figure) is placed on an insulated ground or bracket to prevent the measurement loop from being introduced into the ground or metal bracket, thereby causing errors;

[0083] (2) Press the calibration device port to Figure 4 Connect the electrodes to the corresponding electrode positions of the instrument to establish a current conduction loop;

[0084] (3) Power on the instrument, start the instrument, and guide the instrument to stabilize and reach the measurement state;

[0085] (4) Adjust the resistivity position of the calibration device port and record the corresponding signal measured by the instrument. This step can change the resistivity position linearly or logarithmically. The resistivity value can change from small to large or from large to small.

[0086] (5) Fit the data to establish the relationship between the known resistivity of the calibration device and the measured signal. Generally, it is a linear function or a quadratic polynomial function;

[0087] (6) The fitted polynomial coefficients are the calibration relationship and instrument scale coefficients. When the instrument measures unknown formations, the measurement signal is introduced according to this relationship to obtain the formation resistivity value.

[0088] In summary, the calibration device and method for the downhole lateral imaging resistivity instrument provided by the present invention connects the port of the calibration device to the electrode according to the current loop relationship between the transmitting electrode and the receiving electrode and the formation, and simulates the electrical environment of the formation where the downhole instrument is located on the ground. The contribution value of the formation and mud resistivity around the instrument can be flexibly changed, and the function verification test of the downhole lateral imaging resistivity instrument and the calibration of the relationship between the instrument measurement signal and the formation resistivity can be realized in the workshop or the drilling site. Rapid calibration of the downhole lateral imaging resistivity instrument can be realized, and the device is compact and portable, which improves flexibility.

[0089] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0090] The "one embodiment" or "embodiment" mentioned in the specification means that the specific features, structures or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment" or "embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment.

[0091] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A calibration device for a lateral imaging resistivity instrument while drilling, characterized in that: The device comprises: Ports, including a transmitting electrode positive port, a transmitting electrode negative port and a receiving electrode port, which are respectively connected to the transmitting electrode positive electrode, the transmitting electrode negative electrode and the receiving electrode arranged on the drill collar in a one-to-one correspondence; A formation environment simulation module, comprising a first formation unit and a second formation unit, wherein a first end of the first formation unit is connected to the negative port of the transmitting electrode, and a first end of the second formation unit is connected to the receiving electrode port; an annular drilling fluid simulation module, a first end of which is connected to the positive port of the transmitting electrode, and a second end of which is connected to the second end of the first formation unit and the second end of the second formation unit; The transmitting electrode positive port includes a first positive port and a second positive port, and the transmitting electrode negative port includes a first negative port and a second negative port; The first formation unit includes: a first simulation unit and a second simulation unit, the first end of the first simulation unit is connected to the first negative port, and the first end of the second simulation unit is connected to the second negative port; the second formation unit includes a third simulation unit, and the first end of the third simulation unit is connected to the receiving electrode port.

2. The lateral imaging resistivity while drilling instrument calibration device according to claim 1, characterized in that: The annular drilling fluid simulation module includes: a fourth simulation unit and a fifth simulation unit, wherein a first end of the fourth simulation unit is connected to the first positive port, and a first end of the fifth simulation unit is connected to the second positive port.

3. The calibrating device for a lateral imaging resistivity instrument while drilling according to claim 2, characterized in that: The second end of the first analog unit, the second end of the second analog unit, the second end of the third analog unit, the second end of the fourth analog unit, and the second end of the fifth analog unit are connected to each other.

4. The calibrating device for a lateral imaging resistivity instrument while drilling according to claim 1, characterized in that: The device also comprises: A gear switching device has a first end connected to the port and a second end connected to the formation environment simulation module and the annular drilling fluid simulation module.

5. The calibrating device for a lateral imaging resistivity instrument while drilling according to claim 4, characterized in that: The gear switching device includes a plurality of gears, and each gear corresponds to two connection ends, which are respectively connected to the negative port of the transmitting electrode and the positive port of the transmitting electrode.

6. The calibrating device for a lateral imaging resistivity while drilling instrument according to claim 4, characterized in that: The number of the gear switching devices is the same as the number of the transmitting electrodes, and the multiple gear switching devices are controlled in a linkage arrangement.

7. A method for calibrating a lateral imaging resistivity instrument while drilling, characterized in that: The instrument calibration process is performed by the device according to any one of claims 1 to 6, and the method comprises the following steps: linearly or logarithmically varying the resistivity of the device and recording corresponding measurement data; Fitting the measured data to establish a relationship between the known resistivity of the calibration device and the measured data; Based on the relationship, a calibration relationship and an instrument scale factor are obtained.

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