Dipole reflection shear wave measurement system and design method thereof, electronic equipment and medium
By designing a dipole reflective transverse wave measurement system, the problem of difficulty in directly observing and measuring reflected transverse waves under dipole excitation in the wellbore in the laboratory is solved, and effective verification and scale of dipole transverse wave acoustic reflection imaging logs is achieved, which improves the operability and practical value of the technology.
Patent Information
- Application Number
- CN202011033110.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-09-27
- Publication Date
- 2025-04-01
- Estimated Expiration
- 2040-09-27
AI Technical Summary
The prior art is difficult to directly observe and measure the reflected transverse waves under dipole excitation of the wellbore in the laboratory, resulting in huge challenges in the promotion and application of dipole transverse wave acoustic reflection imaging well logging technology and method verification.
A dipole reflective transverse wave measurement system is designed, including a trough-shaped model well, artificial formation module, dipole transducer and logging control and acquisition module. By conducting experimental design of dipole reflective transverse waves, dipole transverse wave acoustic reflection imaging logs are verified and scaled.
It has achieved effective verification and scale for dipole transverse wave acoustic reflection imaging well logging, which has strong operability and flexibility, solved the problem of direct measurement of reflected transverse waves, and promoted the scientific research and practical value of this technology.
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Figure CN114428351B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of geophysical well logging, and more specifically, to a dipole reflection shear wave measurement system and a design method thereof, electronic equipment and a medium. Background Art
[0002] In recent years, geophysical acoustic logging technology has developed from "one hole close view" to "one hole far view", especially dipole shear wave acoustic reflection imaging logging technology has become a hot spot in the field of geophysical logging, and has been widely used in the exploration and development of concealed oil and gas reservoirs. Its radial detection depth has increased from about 1 meter around the well to tens of meters, greatly increasing the detection capability of acoustic logging. Tang et al. observed the shear wave reflection phenomenon from dipole bending waves and proposed a dipole shear wave acoustic reflection imaging logging method. Wei and Tang studied the dipole radiation directivity, reflection coefficient and receiving directivity, and pointed out that SH shear waves have the widest radiation coverage and higher reflection sensitivity. Wei Zhoutuo et al. proposed a method for long-distance detection of dipole shear waves below the cutoff frequency of the sound source, which provides a theoretical basis for longer-distance acoustic reflection detection. In order to observe the acoustic reflection phenomenon in the laboratory, people have carried out a large number of related attempts. Zhou Jihong measured the reflected waves of a scaled-down model well with cracks near the well in the laboratory and observed the reflected longitudinal waves from the vertical cracks near the well; Che Xiaohua and others made a number of scaled-down models with different inclination angles, different materials and different shapes in the laboratory to study the characteristics of reflected longitudinal waves. The above work is all experimental schemes and devices designed for reflected longitudinal waves. For the lower frequency wellbore dipole bending waves, in order to effectively observe and collect reflected shear waves, a larger volume of natural or artificial rock models is required, which makes it extremely difficult to make reflector models and it is difficult to achieve laboratory measurement of reflected shear waves. Wei Zhoutuo and others carried out experimental research on dipole shear wave acoustic reflection imaging logging. By measuring the boundary reflected shear waves of natural rocks, it was verified that the dipole sound source has obvious azimuth directivity for the wellbore reflector. However, the experimental model and scheme still use the measurement process of reflected longitudinal waves. The reflected shear waves are superimposed on the wellbore bending waves with an amplitude thousands of times larger and cannot be directly observed. Up to now, the reflected shear waves under the dipole excitation of the borehole have not been directly measured and observed in the laboratory, which brings great challenges to the continued promotion and application of the dipole shear wave acoustic reflection imaging logging technology and the verification of the method. The main problems faced by its experimental measurement are: ① From the high-frequency monopole sound source excitation of the borehole (about 100-150kHz) to the low-frequency dipole sound source excitation of the borehole (about 10-30kHz), the wavelength increases several times, and the radial distance of the far field increases significantly. A borehole reflector experimental model several times larger is required to meet the separation and direct observation of the bending wave field and the reflected shear wave; ② The setting of the reflector beside the wellbore, natural rocks are mostly measured by natural boundaries (such as reflectors formed by rock-air) or a flat plate of non-rock material is inserted beside the well of the artificial experimental model, which increases the cost of making the borehole reflector model. At the same time, other natural boundaries of the model will interfere with the direct measurement of the reflected shear wave.
[0003] Based on the above analysis, there is no corresponding laboratory equipment at home and abroad to verify and calibrate the dipole shear wave acoustic reflection imaging logging. It is necessary to develop a dipole reflection shear wave measurement system and its design method, electronic equipment and medium to provide a basis for establishing a reflector experimental interpretation model.
[0004] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to those skilled in the art. Summary of the invention
[0005] The present invention proposes a dipole reflection shear wave measurement system and a design method thereof, an electronic device and a medium, which can verify and calibrate the dipole shear wave acoustic reflection imaging logging by experimentally designing the dipole reflection shear wave measurement system, have strong operability and flexibility, and have great scientific research and practical value for the acoustic wave reflection imaging logging method, instrument calibration and application effect.
[0006] In a first aspect, an embodiment of the present disclosure provides a dipole reflection shear wave measurement system, comprising:
[0007] A slot-shaped model well, in which the well slot is filled with fluid;
[0008] An artificial formation module, comprising a plurality of artificial formation modules, which are immersed in the fluid of the well slot side by side, a measuring well through hole is arranged at the lower part of the artificial formation module, and each artificial formation module is provided with a reflection well hole;
[0009] A pair of dipole transducers, the measuring heads of which are both arranged in the through hole of the measuring well, and the other ends of which are connected to the logging control and acquisition module;
[0010] The logging control and acquisition module is used to control the dipole transducer and acquire data.
[0011] Preferably, the dipole transducer comprises a dipole receiving transducer and a dipole transmitting transducer.
[0012] Preferably, the logging control and acquisition module includes:
[0013] A single-axis positioning guide rail is erected at the upper end of the slot-shaped model well, connects the dipole receiving transducer and the dipole transmitting transducer, and is used to adjust the positions of the dipole receiving transducer and the dipole transmitting transducer.
[0014] Preferably, the logging control and acquisition module includes:
[0015] A power source is connected to the dipole transmitting transducer and provides a transmitting signal to the dipole transmitting transducer.
[0016] Preferably, the logging control and acquisition module includes:
[0017] The data acquisition module is connected to the dipole receiving transducer and is used to receive the signal of the dipole receiving transducer.
[0018] In a second aspect, the embodiments of the present disclosure further provide a design method for a dipole reflection shear wave measurement system, including:
[0019] Determine the geometric similarity scale factor of the dipole reflection shear wave measurement system and determine the borehole diameter;
[0020] Determine the minimum distance between the measurement well through hole and the reflection well through hole;
[0021] Determine the minimum distance between the measuring well and the bottom of the slot model well.
[0022] Preferably, determining the minimum distance between the measurement well through hole and the reflection well through hole comprises:
[0023] The fixed formation elastic attribute combination is P-wave velocity, S-wave velocity and formation volume density;
[0024] According to the borehole diameter and the main frequency of the dipole sound source excitation, the waveform of the borehole reflected shear wave, the amplitude of the reflected wave, and the arrival time of the reflected wave are calculated at different distances between the reflection well through hole and the measurement well through hole, and the minimum distance between the measurement well through hole and the reflection well through hole is determined.
[0025] Preferably, determining the minimum distance between the measuring well and the bottom of the slot model well comprises:
[0026] Starting from the boundary of the slot model well, along the plane centerline perpendicular to the logging direction, the positions of the measuring well through-holes and the reflection well through-holes are evenly moved at a fixed interval, and the arrival time of the reflected wave in the measuring well and the arrival time of the reflected shear wave from the slot model well are calculated respectively, thereby determining the minimum distance between the measuring well and the bottom of the slot model well.
[0027] In a third aspect, an embodiment of the present disclosure further provides an electronic device, the electronic device comprising:
[0028] A memory storing executable instructions;
[0029] A processor runs the executable instructions in the memory to implement the design method of the dipole reflection shear wave measurement system.
[0030] In a fourth aspect, an embodiment of the present disclosure further provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the design method of the dipole reflection shear wave measurement system is implemented.
[0031] The methods and apparatus of the present invention have other features and advantages that will be apparent from, or will be described in detail in, the accompanying drawings and subsequent detailed descriptions incorporated herein, which together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.
[0033] Figure 1a and Figure 1b Schematic diagrams of a calculation model when a formation interface and a coplanar open hole wellbore exist beside the well as reflectors according to an embodiment of the present invention are respectively shown.
[0034] Figure 2a and Figure 2b They are shown according to Figure 1a and Figure 1b Schematic diagram of the finite element meshing of the computational model.
[0035] Figure 3a and Figure 3b They are shown according to Figure 1a and Figure 1b Schematic diagram of the liquid-filled well array waveform.
[0036] Figure 4 A schematic diagram of a dipole reflection shear wave measurement system according to an embodiment of the present invention is shown.
[0037] Figure 5 A flow chart showing the steps of a method for designing a dipole reflection shear wave measurement system according to an embodiment of the present invention.
[0038] Figure 6a and Figure 6b A stereoscopic view and a cross-sectional view of an artificial formation module according to an embodiment of the present invention are respectively shown.
[0039] Figure 7a and Figure 7b They are shown according to Figure 6a and Figure 6b Schematic diagram of the wellbore acoustic field of the artificial formation module and the dipole reflection shear wave waveform of the model wellbore.
[0040] Description of reference numerals:
[0041] 1. Slot-shaped model well; 2. Water medium; 3. Artificial formation module; 4. Measuring well through hole; 5. Reflection well hole; 6. Dipole receiving transducer; 7. Dipole transmitting transducer; 8. Single-axis positioning guide rail; 9. Power source; 10. Data acquisition module; 11. Computer. DETAILED DESCRIPTION
[0042] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.
[0043] The present invention provides a dipole reflection shear wave measurement system, comprising:
[0044] A slot-shaped model well, in which the well slot is filled with fluid;
[0045] The artificial formation module comprises a plurality of artificial formation modules, which are immersed in the fluid of the well slot side by side, a measuring well through hole is arranged at the bottom of the artificial formation module, and each artificial formation module is provided with a reflection well hole;
[0046] A pair of dipole transducers, the measuring heads of which are both arranged in the through hole of the measuring well, and the other end of which is connected to the logging control and acquisition module;
[0047] The logging control and acquisition module is used to control the dipole transducer and collect data.
[0048] In one example, the dipole transducer includes a dipole receiving transducer and a dipole transmitting transducer.
[0049] In one example, the logging control and acquisition module includes:
[0050] The single-axis positioning guide rail is erected at the upper end of the slot-shaped model well, connects the dipole receiving transducer and the dipole transmitting transducer, and is used for adjusting the positions of the dipole receiving transducer and the dipole transmitting transducer.
[0051] In one example, the logging control and acquisition module includes:
[0052] The power source is connected to the dipole transmitting transducer and provides a transmitting signal to the dipole transmitting transducer.
[0053] In one example, the logging control and acquisition module includes:
[0054] The data acquisition module is connected to the dipole receiving transducer and is used to receive the signal of the dipole receiving transducer.
[0055] Specifically, the dipole reflection shear wave measurement system according to the present invention comprises:
[0056] The trough-shaped model well is welded from PVC material, and the artificial formation module and water medium are placed inside the well trough.
[0057] The artificial formation module includes multiple artificial formation modules, which are made of speed and density controllable materials such as cement or resin. Different artificial formation modules can be freely combined and immersed in the water medium of the well slot side by side. A measuring well through hole is arranged at the bottom of the artificial formation module. Each artificial formation module is provided with a reflection well hole, and the number of reflection well holes can be set as needed. A cylinder made of any material is fixed at the designed position before the artificial formation module is cast, and then the module is cast. Finally, a measuring well through hole is drilled uniformly, and the positions of the measuring well through holes of different modules are the same.
[0058] A pair of dipole transducers, including a dipole receiving transducer and a dipole transmitting transducer, have their measuring heads set in the through hole of the measuring well, and the other end is connected to the logging control and acquisition module; by changing the source distance to record the full wave array waveform, the source distance is fixed and the transducer is moved at the same time, and the full wave logging profile that changes with the logging depth can be recorded. Through the wave field separation in the time domain, the formation time difference and the required reflected shear wave waveform can be calculated respectively.
[0059] The logging control and acquisition module is used to control the dipole transducer and collect data, and specifically includes: a single-axis positioning guide rail, which is set up at the upper end of the slot-shaped model well, connects the dipole receiving transducer and the dipole transmitting transducer, provides a minimum 0.2mm step positioning control, drives the dipole receiving transducer and the dipole transmitting transducer to move in the through hole of the measuring well through the connecting arm, and is used to adjust the position of the dipole receiving transducer and the dipole transmitting transducer; the power source uses a pulse excitation method to excite the dipole transmitting transducer to work, connects the dipole transmitting transducer, and provides a transmitting signal to the dipole transmitting transducer; the data acquisition module uses a virtual oscilloscope, which is connected to the dipole receiving transducer and is used to receive the signal of the dipole receiving transducer; the above control and waveform processing are all performed on a computer through software.
[0060] The present invention also provides a design method for a dipole reflection shear wave measurement system, comprising:
[0061] Determine the geometric similarity scale factor of the dipole reflection shear wave measurement system and determine the borehole diameter;
[0062] Determine the minimum distance between the measurement well through hole and the reflection well through hole;
[0063] Determine the minimum distance between the measuring well and the bottom of the slot model well.
[0064] In one example, determining a minimum distance between a measurement well through hole and a reflection well through hole includes:
[0065] The fixed formation elastic attribute combination is P-wave velocity, S-wave velocity and formation volume density;
[0066] According to the borehole diameter and the main frequency of the dipole sound source excitation, the waveform of the borehole reflected shear wave, the amplitude of the reflected wave, and the arrival time of the reflected wave are calculated at different distances between the reflection well through hole and the measurement well through hole, and the minimum distance between the measurement well through hole and the reflection well through hole is determined.
[0067] In one example, determining a minimum distance between the measurement well and the bottom of the slot model well includes:
[0068] Starting from the boundary of the slot model well, along the plane centerline perpendicular to the logging direction, the positions of the measuring well through-holes and the reflection well through-holes are evenly moved at a fixed interval, and the arrival time of the reflected wave in the measuring well and the arrival time of the reflected shear wave from the slot model well are calculated respectively, thereby determining the minimum distance between the measuring well and the bottom of the slot model well.
[0069] Figure 1a and Figure 1b Schematic diagrams of a calculation model when a formation interface and a coplanar open hole wellbore exist beside the well as reflectors according to an embodiment of the present invention are respectively shown.
[0070] Figure 2a and Figure 2b They are shown according to Figure 1a and Figure 1b Schematic diagram of the finite element meshing of the computational model.
[0071] Figure 3a and Figure 3b They are shown according to Figure 1a and Figure 1b Schematic diagram of the liquid-filled well array waveform.
[0072] Specifically, Figure 1a This is the case where there is a stratum interface 10 meters away from the well. Figure 1b There is a coplanar open hole (as a reflector) 10 meters away from the well. Figure 2a , Figure 2b The corresponding mesh division diagram is given. Figure 3a and Figure 3b They are shown according to Figure 1a and Figure 1b Schematic diagram of the waveform of the liquid-filled borehole array, with a source distance range of 2.0 to 4.1 m. The gray line in the figure shows the theoretically calculated SH reflection shear wave arrival time curve. According to the conclusion of Wei and Tang, when the dipole sound source works in a liquid-filled borehole, in addition to exciting the bending wave mode propagating along the well, it also radiates longitudinal and shear waves into the formation. When the dipole vibration direction is parallel to the direction of the reflection interface beside the well, a pure SH reflection shear wave will be generated in the vibration plane of the sound source. Figure 3a , Figure 3bIt can be seen that the first wave to reach the receiver is the bending wave with the largest amplitude in the waveform that propagates along the well, and the last wave to arrive is the SH reflected shear wave. Compared with the direct bending wave, the SH reflected shear wave has a smaller amplitude. Figure 3a and Figure 3b It can be seen that although the SH reflected shear wave amplitude of the latter is only one-third of that of the former, its reflected wave amplitude is still considerable. From the arrival time, there is no superposition phenomenon between the bending wave and the reflected shear wave.
[0073] The above numerical analysis shows that by setting a coplanar fluid-filled wellbore at a certain distance from the well, the measurement of dipole reflected sound waves can be realized. Through a large number of numerical calculations, taking into account the influence of the natural interface of the experimental model, the minimum distance between the reflection wellbore and the measuring wellbore (main well) can be easily designed to solve the two main problems faced by the above experimental measurements.
[0074] The design method of the dipole reflection shear wave measurement system according to the present invention comprises:
[0075] Determine the geometric similarity proportional coefficient of the dipole reflection shear wave measurement system and the borehole diameter; according to the geometric similarity criterion in acoustic theory, the model to be designed will be based on the sound source excitation frequency and the borehole diameter as the basis parameters to ensure that the ratio λ / d of the acoustic wave wavelength λ of the experimental model to the borehole diameter d must be approximately equal to the λ / d of the actual logging object. According to this similarity proportional coefficient, the formation model is proportionally reduced.
[0076] Determine the minimum distance between the through hole of the measuring well and the through hole of the reflection well; input the determined wellbore diameter and the main frequency of the dipole sound source excitation into the numerical simulation program, fix the formation elastic property combination (P wave velocity, S wave velocity and formation volume density), calculate the wellbore reflected S wave waveform under different distances between the reflection well and the measuring well, and calculate the amplitude and arrival time of the reflected wave. Repeat the above calculation steps, perform numerical calculations on different distances between the reflection well and the measuring well under multiple typical formation elastic property combinations, and determine the minimum distance between the reflection well and the measuring well for the typical formation property combination.
[0077] Determine the minimum distance between the measuring well and the bottom of the slot of the slot model well; fix the combination of formation elastic properties and the minimum distance between the measuring well through hole and the reflection well through hole, starting from the boundary of the slot model well, along the plane centerline perpendicular to the logging direction, evenly move the positions of the measuring well through hole and the reflection well through hole at a fixed interval, calculate the arrival time of the reflected wave in the measuring well and the arrival time of the reflected shear wave from the slot model well, repeat the above calculation steps to determine that the arrival time of the reflected shear wave at different boundaries of the experimental model will not interfere with the reflected shear wave of the measuring well hole, and at the same time meet the minimum volume of the experimental model, and determine the minimum distance between the measuring well and the bottom of the slot of the slot model well.
[0078] Through the above three steps, we can obtain the diameter of the measuring well when the experimental model volume is the smallest, the minimum distance between the measuring well and the reflection well, the spatial relative position of the measuring well and the model boundary, and the corresponding formation attribute combination. There is no restriction on the reflection well diameter and model height, which can be adjusted arbitrarily according to experimental requirements.
[0079] The present invention also provides an electronic device, which includes: a memory storing executable instructions; and a processor, which runs the executable instructions in the memory to implement the above-mentioned design method of the dipole reflection shear wave measurement system.
[0080] The present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the design method of the dipole reflection shear wave measurement system is implemented.
[0081] To facilitate understanding of the solutions and effects of the embodiments of the present invention, four specific application examples are given below. Those skilled in the art should understand that the examples are only for facilitating understanding of the present invention, and any specific details thereof are not intended to limit the present invention in any way.
[0082] Example 1
[0083] Figure 4 A schematic diagram of a dipole reflection shear wave measurement system according to an embodiment of the present invention is shown.
[0084] like Figure 4 As shown, the dipole reflection shear wave measurement system comprises:
[0085] The trough-shaped model well 1 is welded from PVC materials, and an artificial formation module and a water medium 2 are placed inside the well trough.
[0086] The artificial formation module includes multiple artificial formation modules 3, which are made of speed and density controllable materials such as cement or resin. Different artificial formation modules 3 can be freely combined and immersed in the water medium 2 of the well slot side by side. A measuring well through hole 4 is arranged at the lower part of the artificial formation module. Each artificial formation module 3 is provided with a reflection well hole 5. The number of reflection well holes 5 can be set as needed. A cylinder made of any material is fixed at the designed position before the artificial formation module is cast, and then the module is cast. Finally, the measuring well through hole 4 is uniformly drilled, and the position of the measuring well through holes 4 of different modules is the same.
[0087] A pair of dipole transducers, including a dipole receiving transducer 6 and a dipole transmitting transducer 7, have their measuring heads both arranged in the through hole 4 of the measuring well, and the other end connected to the logging control and acquisition module; by changing the source distance to record the full wave array waveform, fixing the source distance and moving the transducer at the same time, the full wave logging profile that changes with the logging depth can be recorded. Through the wave field separation in the time domain, the formation time difference and the required reflected shear wave waveform can be calculated respectively.
[0088] The logging control and acquisition module is used to control the dipole transducer and collect data, and specifically includes: a single-axis positioning guide rail 8, which is set up at the upper end of the slot-shaped model well 1, connected to the dipole receiving transducer 6 and the dipole transmitting transducer 7, and provides a minimum 0.2mm step positioning control. The connecting arm drives the dipole receiving transducer 6 and the dipole transmitting transducer 7 to move in the measuring well through hole 4, and is used to adjust the positions of the dipole receiving transducer 6 and the dipole transmitting transducer 7; the power source 9 uses a pulse excitation method to excite the dipole transmitting transducer 7 to work, is connected to the dipole transmitting transducer 7, and provides a transmitting signal to the dipole transmitting transducer 7; the data acquisition module 10 uses a virtual oscilloscope, is connected to the dipole receiving transducer 6, and is used to receive the signal of the dipole receiving transducer 6; the above control and waveform processing are all performed on the computer 11 through software.
[0089] Example 2
[0090] Figure 5 A flow chart showing the steps of a method for designing a dipole reflection shear wave measurement system according to an embodiment of the present invention.
[0091] like Figure 5 As shown, the design method of the dipole reflection shear wave measurement system includes: step 101, determining the geometric similarity proportional coefficient of the dipole reflection shear wave measurement system and determining the borehole diameter; step 102, determining the minimum distance between the measurement well through hole and the reflection well through hole; step 103, determining the minimum distance between the measurement well and the bottom of the slot model well.
[0092] Figure 6a and Figure 6b A stereoscopic view and a cross-sectional view of an artificial formation module according to an embodiment of the present invention are respectively shown.
[0093] In order to increase the amplitude of reflected shear waves, three reflection wellbore combinations with a distance of 2-3 cm were designed. The artificial formation modules such as 6a, Figure 6b shown.
[0094] The diameter of the measuring well through hole is selected to be 2 cm. According to the principle of geometric similarity, the similarity proportional coefficient is equal to the actual wellbore diameter divided by the experimental model well diameter, that is, 20 / 2=10, and a proportional similarity coefficient of 10:1 is adopted; the main frequency of the dipole sound source excitation in the experiment can be obtained as 2000Hz*10=20KHz.
[0095] Figure 7a and Figure 7b They are shown according to Figure 6a and Figure 6b Schematic diagram of the wellbore acoustic field of the artificial formation module and the dipole reflection shear wave waveform of the model wellbore.
[0096] The measuring well through hole is placed at the coordinate position (x=0, y=5), and the reflection well combination is along the direction indicated by the arrow. Starting from a distance of 5 cm, the full-wave waveform of the wellbore corresponding to the distance between the measuring well through hole and the reflection wellbore is calculated when the distance between the measuring well through hole and the reflection wellbore is 5, 10, 15, 20, 25, 30, 35, and 40 cm, respectively. When the arrival time of the reflected shear wave at the left and right ends of the measuring well is greater than the arrival time of the reflected shear wave at the measuring wellbore, and the volume of the experimental model is minimized, the spatial position of the measuring well and the reflection well under the optimal elastic properties is obtained, as shown in Figure 7a As shown in the figure, the borehole acoustic field corresponding to the spatial position of the artificial formation module. It can be seen that when the measurement well through hole and the reflection well hole are selected to be 20 cm and the formation shear wave velocity is 1180m / s, the arrival of the reflected shear wave is later than the borehole bending wave, and the two do not interfere with each other. At the same time, it can be clearly seen that the reflected shear waves from the tangent points of the left and right end faces arrive later than the reflected shear wave and do not interfere with each other.
[0097] According to the dipole reflection shear wave experimental measurement system provided by the present invention, the artificial formation module is placed flat in a slot-shaped model well, and a Burst excitation sound source is used to excite the dipole transmitting transducer through a power amplifier to radiate shear waves to the well. When the shear wave propagates to the reflection well combination, it is reflected and received by the dipole receiving transducer of the measured wellbore. The source distance between the dipole transmitting transducer and the dipole receiving transducer is set to 20 cm. The dipole transmitting transducer is fixed, and the dipole receiving transducer is controlled to move at equal intervals of 1 cm through a single-axis positioning guide rail. The full-wave waveform of the wellbore is recorded at each position through the HPE1437A data acquisition system until the dipole receiving transducer moves to the leftmost end of the formation model. Figure 7b As shown in the figure, the experiment collected 6 array waveforms within the range of 0.2-0.25 meters. It can be seen that the diamond box is the location of the reflected shear wave, which is consistent with the theoretical reflected shear wave arrival time and is consistent with the following Figure 7a Compared with the theoretical model array waveform, the two have good consistency.
[0098] Example 3
[0099] The present disclosure provides an electronic device, which includes: a memory storing executable instructions; a processor, which runs the executable instructions in the memory to implement the design method of the dipole reflection shear wave measurement system.
[0100] An electronic device according to an embodiment of the present disclosure includes a memory and a processor.
[0101] The memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.
[0102] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present disclosure, the processor is used to run the computer-readable instructions stored in the memory.
[0103] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present disclosure.
[0104] For detailed description of this embodiment, reference may be made to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.
[0105] Example 4
[0106] An embodiment of the present disclosure provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the design method of the dipole reflection shear wave measurement system is implemented.
[0107] According to the computer-readable storage medium of the embodiment of the present disclosure, non-transitory computer-readable instructions are stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of each embodiment of the present disclosure are executed.
[0108] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).
[0109] Those skilled in the art should understand that the purpose of the above description of the embodiments of the present invention is only to exemplarily illustrate the beneficial effects of the embodiments of the present invention, and is not intended to limit the embodiments of the present invention to any given examples.
[0110] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.
Claims
1. A dipole reflection shear wave measurement system, characterized in that: include: A slot-shaped model well, in which the well slot is filled with fluid; An artificial formation module, comprising a plurality of artificial formation modules, which are immersed in the fluid of the well slot side by side, a measuring well through hole is arranged at the lower part of the artificial formation module, and each artificial formation module is provided with a reflection well hole; A pair of dipole transducers, the measuring heads of which are both arranged in the through hole of the measuring well, and the other ends of which are connected to the logging control and acquisition module; A logging control and acquisition module, used for controlling the dipole transducer and acquiring data; Among them, the artificial formation modules are made of speed and density controllable materials, and different artificial formation modules can be freely combined.
2. The dipole reflection shear wave measurement system according to claim 1, wherein: The dipole transducer comprises a dipole receiving transducer and a dipole transmitting transducer.
3. The dipole reflection shear wave measurement system according to claim 2, wherein: The logging control and acquisition module includes: A single-axis positioning guide rail is erected at the upper end of the slot-shaped model well, connects the dipole receiving transducer and the dipole transmitting transducer, and is used to adjust the positions of the dipole receiving transducer and the dipole transmitting transducer.
4. The dipole reflection shear wave measurement system according to claim 2, wherein: The logging control and acquisition module includes: A power source is connected to the dipole transmitting transducer and provides a transmitting signal to the dipole transmitting transducer.
5. The dipole reflection shear wave measurement system according to claim 2, wherein: The logging control and acquisition module includes: The data acquisition module is connected to the dipole receiving transducer and is used to receive the signal of the dipole receiving transducer.
6. A design method for a dipole reflection shear wave measurement system, based on the dipole reflection shear wave measurement system according to any one of claims 1 to 5, characterized in that: include: Determine the geometric similarity scale factor of the dipole reflection shear wave measurement system and determine the borehole diameter; Determine the minimum distance between the measurement well through hole and the reflection well through hole; Determine the minimum distance between the measuring well and the bottom of the slot model well; The minimum distance between the measuring well through hole and the reflection well through hole is determined as follows: The fixed formation elastic attribute combination is P-wave velocity, S-wave velocity and formation volume density; According to the borehole diameter and the main frequency of the dipole sound source excitation, the waveform of the borehole reflected shear wave, the amplitude of the reflected wave, and the arrival time of the reflected wave are calculated at different distances between the reflection well through hole and the measurement well through hole, and the minimum distance between the measurement well through hole and the reflection well through hole is determined.
7. The design method of the dipole reflection shear wave measurement system according to claim 6, wherein: Determine the minimum distance between the measuring well and the bottom of the slot model well including: Starting from the boundary of the slot model well, along the plane centerline perpendicular to the logging direction, the positions of the measuring well through-holes and the reflection well through-holes are evenly moved at a fixed interval, and the arrival time of the reflected wave in the measuring well and the arrival time of the reflected shear wave from the slot model well are calculated respectively, thereby determining the minimum distance between the measuring well and the bottom of the slot model well.
8. An electronic device, characterized in that: The electronic device comprises: A memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the design method of the dipole reflection shear wave measurement system according to claim 6 or 7.
9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the design method of the dipole reflection shear wave measurement system according to claim 6 or 7 is implemented.