Investigation method and system for deep micro-logging
By employing portable microseismic source multiple excitation and detector group calibration techniques, combined with data processing methods, the problems of high investment and insufficient accuracy in deep micro-logging surveys have been solved, achieving high-precision velocity modeling and seismic imaging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2026-03-31
AI Technical Summary
Existing technologies for deep micro-logging surveys involve high production costs and significant survey difficulties. Furthermore, existing methods struggle to accurately identify initial arrivals at depths exceeding 200m, failing to meet the demands for high-precision and rapid modeling.
Portable microseismic sources were used for multiple excitations. The receiving time was corrected by grouping detectors, the one-way vertical propagation time was calculated, deep micro-logging time curves were plotted, and a velocity model was constructed. The seismic wave data was processed by combining Wiener filtering and centroid frequency shift methods to obtain accurate formation velocity and absorption attenuation information.
It enables efficient and safe acquisition of geological exploration data in deep micro-logging, reduces production input, improves the accuracy of velocity models and seismic imaging quality, and solves the problems of deep micro-logging investigation.
Smart Images
Figure CN121763406A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of petroleum exploration, and more specifically, to a method and system for deep micro-logging. Background Technology
[0002] With pre-stack depth migration becoming the mainstream processing technique, the importance of velocity model accuracy is increasingly prominent. In production, tomographic inversion is generally performed using the first arrival time of the borehole to obtain a velocity model that considers both shallow and deep layers. Due to limitations in the number of spatial sampling points, the tomographic inversion results often do not completely match the actual shallow and deep surface structures. To improve the accuracy of the velocity model, micrologging results are typically used for constrained inversion during the tomographic inversion process, or the velocity field is calibrated and verified based on micrologging results after the tomographic inversion. In areas with extremely thick weathered layers, or to obtain a deep surface velocity model, conducting deep micrologging surveys is unavoidable.
[0003] In existing technologies, the surface micrologging survey method typically employs in-well excitation via electric spark and ground reception via conventional geophones. However, this method requires not only specialized electric spark excitation and cable retraction devices and equipment, but also dedicated water tankers for real-time production support, resulting in significant personnel and equipment investment. Furthermore, due to the limitation of the electric spark source power, the initial arrival of the acquired seismic data is difficult to accurately identify at well depths greater than 150m, making it unsuitable for deep micrologging surveys exceeding 200m. Summary of the Invention
[0004] This application aims to provide a method and system for deep micro-logging investigation, which addresses the problems of high production input and great investigation difficulty in deep micro-logging investigation work in the field, and provides data support for high-quality velocity modeling and seismic imaging.
[0005] The first aspect of this application provides a method for investigating deep micro-logging, the method comprising:
[0006] The portable micro-vibration source is controlled to perform the Nth excitation, and the deep micro-logging data generated by the Nth geophone group is acquired sequentially from the bottom of the well to the wellhead. The deep micro-logging data includes the reception time of the corresponding receiving channel of each geophone in the geophone group.
[0007] Using the received time of the receiving channel corresponding to the repeating detector in the previous detector group after correction, the received time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the received time of each receiving channel in the next detector group after correction. The repeating detector is the last detector in the detector group, and the last detector in the previous detector group is the same as the first detector in the next adjacent detector group.
[0008] The receiving time of the corresponding receiving channel of the calibrated detector is determined as the corresponding first arrival propagation time;
[0009] The one-way vertical propagation time of each receiver channel in the deep micro-logging data is obtained by calculating the first arrival propagation time, the offset distance between the portable micro-source and the wellhead, and the receiving depth of each receiver channel in the deep micro-logging data.
[0010] Based on the one-way vertical propagation time and receiving depth of each receiving channel in the deep micro-logging data, the corresponding deep micro-logging time curves are plotted.
[0011] A velocity model is constructed based on the deep micro-logging time curves.
[0012] Optionally, when the previous detector group is the first detector group, the reception time of each receiving channel in the next detector group adjacent to the previous detector group is corrected based on the reception time of the receiving channel corresponding to the repeating detector in the previous detector group after correction, to obtain the corrected reception time of each receiving channel in the next detector group, including:
[0013] Using the reception time of the receiving channel corresponding to the repeating detector in the first detector group, the reception time of each receiving channel in the next detector group adjacent to the first detector group is corrected to obtain the corrected reception time of each receiving channel in the next detector group.
[0014] Optionally, the receiving times of each receiving channel in the next detector group adjacent to the previous detector group are corrected using the receiving time of the receiving channel corresponding to the repeating detector in the previous detector group, to obtain the corrected receiving times of each receiving channel in the next detector group, including:
[0015] The corrected time difference is obtained by subtracting the receiving time of the receiving channel corresponding to the repeating detector in the previous detector group after correction from the receiving time of the receiving channel corresponding to the first detector in the next detector group adjacent to the previous detector group.
[0016] Based on the corrected time difference, the reception time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the corrected reception time of each receiving channel in the next detector group.
[0017] Optionally, the one-way vertical propagation time of each receiver channel in the deep micrologging data is obtained by calculating the first arrival propagation time, the offset distance between the portable microsource and the wellhead, and the receiving depth of each receiver channel in the deep micrologging data. This includes:
[0018] The first arrival propagation time of each receiver channel in the deep micro-logging data, the offset distance between the portable micro-source and the wellhead, and the receiving depth of each receiver channel in the deep micro-logging data are substituted into the single-way vertical propagation time algorithm to obtain the single-way vertical propagation time of each receiver channel in the deep micro-logging data.
[0019] The expression for the one-way vertical propagation time algorithm is as follows:
[0020]
[0021] Among them, t 0i t represents the one-way vertical propagation time for different receiving channels. i denoted as , where is the initial propagation time for different receiver channels; H is the receiving depth corresponding to different receiver channels; D is the offset distance between the portable microseismic source and the wellhead; and i is the receiver channel number counted from the bottom of the well.
[0022] Optionally, the method further includes:
[0023] The data generated by the repeating detector in the previous detector group is determined as the desired output data, and the data generated by the first detector in the next detector group adjacent to the previous detector group is determined as the data to be corrected.
[0024] The shaping filter factor between the desired output data and the data to be corrected is determined by Wiener filtering.
[0025] Based on the shaping filter factor, the data received by each detector in the next detector group adjacent to the previous detector group are subjected to excitation wavelet inconsistency correction processing to obtain the target data corresponding to each detector.
[0026] The target data is processed by the centroid frequency shift method to obtain the Q value corresponding to the velocity in the formation corresponding to each detector.
[0027] The degree of absorption and attenuation of seismic waves in the strata is determined based on the Q value corresponding to the velocity in the strata corresponding to each detector.
[0028] The second aspect of this application provides a deep micro-logging investigation system, which is used to conduct deep micro-logging investigations using any of the deep micro-logging investigation methods described in the first aspect. The system includes: a portable micro-vibration source, a receiving device, a traction weight, and a shallow refractometer.
[0029] The portable microseismic source is used to perform multiple source excitations and generate seismic waves;
[0030] The receiving device is used to receive seismic waves generated by a portable microseismic source and generate deep micro-logging data;
[0031] The traction weight is used to pull the receiving device into the deep micro-logging well;
[0032] The shallow refractometer is used to analyze and process the deep micro-logging data.
[0033] Optionally, the portable micro-vibration source includes multiple springs, and the number of springs increases accordingly with the depth of the deep micro-logging.
[0034] Optionally, one end of the traction weight is tapered, and the length of the traction weight is 50cm-100cm, the diameter is 70cm-100mm, and the mass is 60kg-100kg.
[0035] Optionally, the receiving device includes: a plurality of detectors and a cable;
[0036] The detector includes a detector head and connecting wires;
[0037] Each of the detectors is distributed on the cable at a preset distance, and the connecting lines of each detector are fixedly connected to the cable.
[0038] Optionally, one end of the cable is connected to the traction weight, and the other end is connected to the shallow refractometer.
[0039] Beneficial effects:
[0040] This application provides a method for investigating deep micro-logging. The method includes: controlling a portable micro-vibration source to perform an Nth excitation, and sequentially acquiring deep micro-logging data generated by the Nth geophone group from the bottom of the well towards the wellhead. The deep micro-logging data includes the reception time of the receiving channel corresponding to each geophone in the geophone group; correcting the reception time of each receiving channel in the next geophone group adjacent to the previous geophone group using the corrected reception time of the receiving channel corresponding to the repeating geophone in the previous geophone group, to obtain the corrected reception time of each receiving channel in the next geophone group, wherein the repeating geophone is the last geophone in the geophone group. The last detector in the previous detector group is the same as the first detector in the next adjacent detector group; the receiving time of the receiving channel corresponding to the corrected detector is determined as the corresponding first arrival propagation time; by calculating the first arrival propagation time of each receiving channel in the deep micrologging data, the offset distance between the portable microsource and the wellhead, and the receiving depth of each receiving channel in the deep micrologging data, the one-way vertical propagation time of each receiving channel in the deep micrologging data is obtained; based on the one-way vertical propagation time and receiving depth of each receiving channel in the deep micrologging data, the corresponding deep micrologging time curve is plotted; a velocity model is constructed based on the deep micrologging time curve.
[0041] By controlling a portable microseismic source for multiple excitations instead of using explosives, safety hazards are eliminated, consumables for explosives are saved, and high transportation and storage costs are avoided. During each excitation, multiple geophones receive the seismic waves generated by the portable microseismic source, generating corresponding deep micrologging data. The geophones in the deep micrologging are divided into multiple geophone groups. Each vibration of the portable microseismic source generates deep micrologging data from a corresponding geophone group; N excitations result in N geophone groups generating corresponding deep micrologging data. The reception time of the receiver channel corresponding to each geophone in the deep micrologging data is corrected to obtain the corresponding first-arrival propagation time. Then, the one-way vertical propagation time is calculated for the first-arrival propagation time of each receiver channel, obtaining the corresponding deep micrologging time curve. Finally, a velocity model is obtained based on the deep micrologging time curve. The method described in this application enables accurate acquisition of deep micro-logging data, solving the problem of high production costs in geological exploration and investigation of deep micro-logging in existing technologies. Furthermore, by processing the time in the deep micro-logging data, the velocity model obtained from this time becomes more accurate and controllable. Attached Figure Description
[0042] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0043] Figure 1 This is a flowchart of a deep micro-logging investigation method provided in an embodiment of this application;
[0044] Figure 2 This is a schematic diagram of the data acquisition process for deep micro-logging provided in an embodiment of this application;
[0045] Figure 3 This is a schematic diagram of deep micro-logging data provided in an embodiment of this application;
[0046] Figure 4 This is a schematic diagram of a deep micro-logging time curve provided in an embodiment of this application;
[0047] Figure 5 This is a schematic diagram illustrating the relationship between velocity and Q value in deep micro-logging according to an embodiment of this application;
[0048] Figure 6 This is a schematic diagram of a traction weight provided in one embodiment of this application. Detailed Implementation
[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0050] This application provides a flowchart of a deep micro-logging investigation method, as shown in the embodiments below. Figure 1 As shown. Specifically, this application provides a method for determining the investigation method for deep micro-logging, the method comprising:
[0051] S11: Control the portable micro-vibration source to perform the Nth excitation, and sequentially acquire the deep micro-logging data generated by the Nth geophone group from the bottom of the well to the wellhead. The deep micro-logging data includes the reception time of the corresponding receiving channel of each geophone in the geophone group.
[0052] In the exploration of mineral resources such as oil and natural gas, deep micrologging is an important means of obtaining information about subsurface rock formations. Through deep micrologging data, we can understand the physical properties of subsurface rock formations (such as resistivity, porosity, and permeability), rock type, fluid properties (oil, gas, and water), and key parameters such as formation pressure and temperature. This allows us to assess reservoir potential and provide a basis for drilling decisions and development plan design. Specifically, by investigating deep micrologging data, we can obtain the one-way vertical propagation time corresponding to each receiver channel. Using this one-way vertical propagation time, a velocity model can be constructed, which helps in the accurate assessment of subsurface rock formations.
[0053] In this embodiment, a self-made portable microseismic source is placed on the surface near the wellhead of the deep micrologging well. Multiple geophones are sequentially placed inside the deep micrologging well. After the portable microseismic source is activated, the geophones in the deep micrologging well receive the seismic waves and generate corresponding deep micrologging data. Furthermore, this embodiment also includes a shallow refractometer. There is a signal connection between the shallow refractometer and the geophones; that is, the shallow refractometer acquires the corresponding deep micrologging data from the geophones and processes the data. However, the number of connections between a shallow refractometer and multiple geophones is limited. For example, a shallow refractometer can only connect to 12 geophones at a time, meaning it can only acquire deep micrologging data generated by these 12 geophones. Therefore, in this application, a method of multiple activations using a portable microseismic source is employed to enable the shallow refractometer to acquire deep micrologging data from different geophones multiple times. At the same time, all the geophones in the deep micro-logging are grouped to obtain multiple geophone groups. For example, a shallow refractometer can only connect 12 geophones at a time, that is, 12 adjacent geophones are set as a geophone group. In this embodiment, the geophones are grouped starting from the geophones at the bottom of the well and sequentially towards the wellhead.
[0054] This embodiment also provides a schematic diagram of the deep micro-logging data acquisition process, such as... Figure 2 As shown. Specifically, the geophones in the deep micro-logging system are divided into N groups, each group sequentially connecting to the shallow refractometer. Therefore, each time the portable micro-source is excited, the corresponding geophone group sends the corresponding deep micro-logging data to the shallow refractometer. After the portable micro-source is excited for the Nth time, the Nth geophone group in the last group generates the corresponding deep micro-logging data and sends it to the shallow refractometer. At this time, the shallow refractometer acquires the deep micro-logging data generated by all geophones from the first to the Nth geophone group, such as... Figure 3 The diagram shown illustrates a deep micro-logging data provided in this embodiment. This deep micro-logging data includes the reception time of each detector's corresponding receiving channel. Each detector has its own corresponding receiving channel, and the reception time is the time it takes for each receiving channel to receive seismic waves.
[0055] S12: Using the received time of the receiving channel corresponding to the repeating detector in the previous detector group after correction, the received time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the received time of each receiving channel in the next detector group after correction. The repeating detector is the last detector in the detector group, and the last detector in the previous detector group is the same as the first detector in the next adjacent detector group.
[0056] S13: Determine the receiving time of the receiving channel corresponding to the corrected detector as the corresponding first arrival propagation time.
[0057] In this embodiment, because seismic waves are affected by underground geological interference during transmission, the signals generated after multiple excitations by the seismic source will produce different seismic waves after passing through the underground medium. These seismic waves, when received by the same geophone, will also generate different seismic data. Therefore, to avoid this error caused by geological interference leading to inconsistent seismic data generated by the same geophone, this embodiment includes duplicate geophones in adjacent geophone groups, i.e., duplicated geophones.
[0058] Specifically, such as Figure 2 As shown, in the direction from the bottom of the well to the wellhead, the last geophone in the previous geophone group is used as the first geophone in the next adjacent geophone group. This geophone is repeated in both geophone groups, hence it is called a repeated geophone. Furthermore, except for the last geophone group, the number of geophones in each other geophone group is the same. For example, in a geophone group of 12 geophones, the first geophone group includes geophones 1-12, with geophone 12 being the last. Then, geophone 12 is used as the first geophone in the second geophone group, meaning the second geophone group includes geophones 12-23.
[0059] To avoid time errors caused by geological interference, this embodiment performs calibration on the receiver channels corresponding to each receiver channel in deep micro-logging. Specifically, using the reception time of the already calibrated repeating receiver channel in the previous detector group as a benchmark, the time difference between the repeating receivers in the previous detector group and the next adjacent detector group is determined. The reception times of each receiver channel in the next adjacent detector group are then calibrated to obtain the calibrated reception times of each receiver channel in the next detector group. In this embodiment, the calibrated reception time is determined as the corresponding first arrival propagation time, that is, the propagation time of the first arrival wave in the seismic wave that the detector actually receives.
[0060] S14: By calculating the first arrival propagation time of each receiver channel in the deep micrologging data, the offset distance between the portable microsource and the wellhead, and the receiving depth of each receiver channel in the deep micrologging data, the one-way vertical propagation time of each receiver channel in the deep micrologging data is obtained.
[0061] The one-way vertical propagation time directly reflects the distance and time relationship between the seismic wave's vertical downward propagation from the portable microseismic source to the geophone, providing a more intuitive reflection of the properties of the subsurface medium. Since the portable microseismic source is located at a certain distance from the wellhead, this embodiment further processes the first-arrival propagation time of each receiver channel in the deep micrologging data to obtain a more intuitive understanding of the vertical propagation time of the seismic waves generated by the portable microseismic source to each geophone. Specifically, the one-way vertical propagation time corresponding to each receiver channel is calculated based on the first-arrival propagation time of each receiver channel in the deep micrologging data, the offset distance between the portable microseismic source and the wellhead, and the receiving depth of each receiver channel in the deep micrologging data.
[0062] S15: Based on the single-way vertical propagation time and receiving depth of each receiving channel in the deep micro-logging data, plot the corresponding deep micro-logging time curve.
[0063] S16: Construct a velocity model based on the deep micro-logging time curves.
[0064] This embodiment also provides a schematic diagram of deep micro-logging time curves, such as... Figure 4 As shown. Specifically, using the one-way vertical propagation time of each receiver channel in the deep micro-logging data as the x-axis and the depth position of each detector in the deep micro-logging well, i.e., the receiving depth of each receiver channel, as the y-axis, a deep micro-logging time curve is plotted for that deep micro-logging well. This time curve allows us to understand the variation in seismic wave propagation time at different depths within the deep micro-logging well. Furthermore, based on this time curve, a precise velocity model corresponding to that deep micro-logging well is constructed. This velocity model reveals the velocity variations of seismic waves within the deep micro-logging well, helping researchers understand the geological conditions of each stratum within the deep micro-logging well and facilitating the development of more precise mining plans.
[0065] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for investigating deep micro-logging. In this method for investigating deep micro-logging, step S12 includes step S21:
[0066] S21: Using the receiving time of the receiving channel corresponding to the repeating detector in the first detector group, correct the receiving time of each receiving channel in the next detector group adjacent to the first detector group to obtain the corrected receiving time of each receiving channel in the next detector group.
[0067] Specifically, when the detector group is the first of N detector groups, the reception time of the first detector group is not corrected; that is, the reception time of each receiving channel corresponding to the first detector group is the first arrival propagation time. When correcting the reception time of each receiving channel of the next detector group adjacent to the first detector group, the reception time of each receiving channel of the next detector group is directly corrected using the receiving channel time of the repeating detector in the first detector group, and the corrected reception time of each receiving channel in the next detector group is obtained.
[0068] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for investigating deep micro-logging. In this method, step S12 includes steps S31 to S32:
[0069] S31: The corrected time difference is obtained by subtracting the receiving time of the receiving channel corresponding to the repeating detector in the previous detector group after correction from the receiving time of the receiving channel corresponding to the first detector in the next detector group adjacent to the previous detector group.
[0070] S32: Based on the correction time difference, the reception time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the corrected reception time of each receiving channel in the next detector group.
[0071] Because there are repeating detectors in the previous and next detector groups, and because after the portable microsource's last excitation, the repeating detectors in the previous detector group generate a receiving time, and after the portable microsource's next excitation, the repeating detectors in the adjacent next detector group generate a receiving time, the difference between the two receiving times is the correction time difference for each detector in the next detector group. Specifically, the correction time difference is obtained by subtracting the receiving time of the channel corresponding to the last detector in the previous detector group (i.e., the repeating detector) from the receiving time of the channel corresponding to the first detector in the adjacent next detector group. For example, the correction time difference is obtained by subtracting the corrected receiving time of the channel corresponding to the 12th detector (the last detector in the first detector group) from the receiving time of the channel corresponding to the 12th detector (the first detector in the second detector group).
[0072] Using the corrected time difference obtained through the above steps, the receiving time of each receiving channel in the next detector group is corrected based on the corrected time difference, thus obtaining the corrected receiving time of each receiving channel in the next detector group, which is the first arrival propagation time of each receiving channel in the next detector group.
[0073] For example, during the first excitation of a portable microseismic source, the reception time of the nth receiving channel (the receiving channel corresponding to the last detector) in the first detector group is t. 1n During the second excitation, the reception time of the nth receiving channel (the receiving channel corresponding to the first detector) in the second detector group is t. 2n Then the time difference between the second excitation and the first excitation is:
[0074] Δt 21 =t 2n -t 1n
[0075] Then, during the second excitation, the corrected first-arrival propagation time of the receiving channels at different depths in the second detector group is:
[0076] T 2n =t 2n -Δt 21
[0077] T 2(n+1) =t 2(n+1) -Δt 21
[0078] ...
[0079] T 2(2n-1) =t 2(2n-1) -Δt 21
[0080] Where, Δt 21 The correction time difference between the second detector group and the first detector group; t 2n t is the reception time of the nth receiving channel of the second detector group; 1n T is the reception time of the nth receiving channel of the first detector group; 2n T is the corrected first-arrival propagation time of the nth receiving channel of the second detector group; 2(n+1) T is the corrected first arrival propagation time of the (n+1)th receiving channel of the second detector group; 2(2n-1) The first arrival propagation time after correction for the (2n-1)th receiving channel of the second detector group.
[0081] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for investigating deep micro-logging. In this method, step S14 includes steps S41 to S42:
[0082] S41: Substitute the first arrival propagation time of each receiver channel in the deep micrologging data, the offset distance between the portable microseismic source and the wellhead, and the receiving depth of each receiver channel in the deep micrologging data into the single-way vertical propagation time algorithm to obtain the single-way vertical propagation time of each receiver channel in the deep micrologging data.
[0083] S42: The expression for the single-pass vertical propagation time algorithm is:
[0084]
[0085] Among them, t 0i t represents the one-way vertical propagation time for different receiving channels. i denoted as , where is the initial propagation time for different receiver channels; H is the receiving depth corresponding to different receiver channels; D is the offset distance between the portable microseismic source and the wellhead; and i is the receiver channel number counted from the bottom of the well.
[0086] Specifically, the first-arrival propagation time of each receiver channel in the deep micrologging data is obtained through the above steps. Simultaneously, based on the placement of the portable microsource on the surface and the wellhead position of the deep micrologging data, the offset distance between the portable microsource and the wellhead is determined. Then, based on the depth position of each detector in the deep micrologging data, the corresponding receiving depth of each receiver channel can be obtained. Substituting the first-arrival propagation time of each receiver channel in the deep micrologging data, the offset distance between the portable microsource and the wellhead, and the receiving depth of each receiver channel in the deep micrologging data into the one-way vertical propagation time algorithm, the one-way vertical propagation time of each receiver channel can be obtained.
[0087] The expression for the one-way vertical propagation time algorithm is as follows:
[0088]
[0089] Among them, t 0i t represents the one-way vertical propagation time for different receiving channels. i denoted as , where is the initial propagation time for different receiver channels; H is the receiving depth corresponding to different receiver channels; D is the offset distance between the portable microseismic source and the wellhead; and i is the receiver channel number counted from the bottom of the well.
[0090] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for investigating deep micro-logging. This method further includes steps S51 to S55:
[0091] S51: Determine the data generated by the repeating detector in the previous detector group as the desired output data, and determine the data generated by the first detector in the next detector group adjacent to the previous detector group as the data to be corrected.
[0092] S52: Determine the shaping filter factor between the desired output data and the data to be corrected using the Wiener filtering method.
[0093] S53: Based on the shaping filter factor, the data received by each detector in the next detector group adjacent to the previous detector group are subjected to excitation wavelet non-uniformity correction processing to obtain the target data corresponding to each detector.
[0094] In this embodiment, by processing the acquired deep micro-logging data, the corresponding Q values for each formation in the deep micro-logging can be obtained. These Q values can then be used to determine the degree of seismic wave absorption and attenuation in each formation. Specifically, after the portable micro-source performs one excitation, the data generated by the repeating detector in the previous detector group is determined as the desired output data. After the portable micro-source performs another excitation, the data generated by the first detector in the next detector group adjacent to the previous detector group is determined as the data to be corrected. The first detector in the next detector group is also the repeating detector in the previous detector group.
[0095] In this embodiment, to correct the data to be corrected to the desired output data, Wiener filtering is used to process both the data to be corrected and the desired output data. Wiener filtering is an optimal linear filtering method based on the minimum mean square error criterion. Wiener filtering can determine the "tool" for correcting the data to be corrected to the desired output data; this "tool" is the shaping filter factor. Using this shaping filter factor, the corrected data can be corrected to the desired output data. Similarly, this "tool" can also be used to correct other data.
[0096] Specifically, to eliminate errors caused by the inconsistency of the excitation wavelet (i.e., the waveform of the seismic wave as it propagates from the seismic source to the detector) received by different detectors, thereby obtaining more accurate and consistent target data, this embodiment performs excitation wavelet inconsistency correction processing on the data received by each detector in the next detector group. Specifically, using the shaping filter factor between the data generated by the repeated detectors in the previous detector group and the data generated by the first detector in the next detector group, excitation wavelet inconsistency correction processing is performed on the data received by each detector in the next detector group, and the target data corresponding to each detector is obtained.
[0097] S54: The target data is processed by the centroid frequency shift method to obtain the Q value corresponding to the velocity in the formation corresponding to each detector.
[0098] S55: Determine the degree of absorption and attenuation of seismic waves in the strata based on the Q value corresponding to the velocity in the strata corresponding to each detector.
[0099] The centroid frequency shift method is a method for estimating the absorption and attenuation characteristics of a subsurface medium based on the change in the centroid frequency as seismic waves propagate. During propagation, due to the inelastic properties of the medium, the high-frequency components of seismic waves gradually attenuate, causing the centroid frequency of the received seismic wave signal to shift towards lower frequencies. By measuring this change in centroid frequency, the quality factor Q of the medium can be estimated, thus revealing the degree of seismic wave absorption and attenuation. Specifically, by processing the target data corresponding to each geophone using the centroid frequency shift method, the Q value corresponding to the velocity in the formation corresponding to each geophone can be obtained, where the velocity refers to the propagation speed of the seismic wave. Based on the propagation speed of the seismic wave in the formation and the Q value of each formation, a curve relationship between the propagation speed and the Q value in each formation can be determined, such as... Figure 5 As shown in the figure, this embodiment also provides a schematic diagram of the relationship between velocity and Q value in deep micro-logging. Furthermore, the Q value is an important parameter describing the absorption and attenuation characteristics of seismic waves; a larger Q value indicates a weaker degree of absorption and attenuation of the seismic waves.
[0100] This application also provides a deep micro-logging investigation system, which is used to conduct deep micro-logging investigations using the deep micro-logging investigation method in any of the above embodiments. The system includes: a portable micro-vibration source, a receiving device, a traction weight, and a shallow refractometer.
[0101] The portable microseismic source is used to perform multiple source excitations and generate seismic waves;
[0102] The receiving device is used to receive seismic waves generated by a portable microseismic source and generate deep micro-logging data;
[0103] The traction weight is used to pull the receiving device into the deep micro-logging well;
[0104] The shallow refractometer is used to analyze and process the deep micro-logging data.
[0105] Specifically, the deep micro-logging investigation system of this application includes a portable microseismic source, a receiving device, a traction weight, and a shallow refractometer. The portable microseismic source is used to perform multiple source excitations and generate seismic waves. The receiving device is used to receive the seismic waves generated by the portable microseismic source and generate deep micro-logging data. The traction weight is used to pull the receiving device into the deep micro-logging area. The shallow refractometer is used to analyze and process the deep micro-logging data.
[0106] Specifically, the usage method of this deep micro-logging survey system is as follows: Determine the drilling location for the deep micro-logging and begin drilling. After the drill bit reaches the designed well depth, cementing is performed using a cementing agent. Then, water is injected into the well to dilute the drilling mud. While maintaining the drill bit's working state, the drill bit is raised from the bottom of the well to the wellhead, and then drilled from the wellhead back to the bottom. This process is repeated to circulate and flush the well, ultimately ensuring that the wellbore is unobstructed, the well wall is smooth, there is no collapse, and no debris falls. At this point, a portable micro-vibration source is placed near the wellhead of the deep micro-logging well. A weight is placed at the bottom of the receiving device, and a steel cable is securely tied to the weight. With the steel cable bearing the weight, the weight pulls the receiving device into the well until the depth of the last receiver in the receiving device reaches the design requirements. Finally, the well is carefully sealed using purchased smooth, non-angular backfill material. To ensure effective well sealing, the sealing process should be carried out gradually. After filling the well with some backfill material, it must be allowed to sink completely to its deepest point before more backfill material is added. Depending on the well depth, the entire sealing process typically lasts 12-48 hours. Once sealing is complete, a portable microseismic source begins to generate seismic waves. The receiving device receives these waves and generates deep micrologging data. A shallow refractometer acquires the deep micrologging data generated by the receiving device and analyzes and processes it to obtain the one-way vertical propagation time corresponding to each receiver channel in the deep micrologging data.
[0107] In another embodiment, the portable micro-vibration source includes multiple springs, and the number of springs increases accordingly with the depth of the deep micro-logging.
[0108] The self-made portable microseismic source works by utilizing the elastic potential energy of a spring combined with the gravitational potential energy of a vibratory weight to generate excitation energy. Since the required excitation energy varies depending on the depth of the micrologging, the number of springs is selected based on the depth of the well. Specifically, the number of springs in the portable microseismic source is increased accordingly with increasing depth to increase elastic potential energy. Preferably, the number of springs can be 10-40, with the final number determined by ensuring the energy requirements are met.
[0109] In another embodiment, one end of the traction weight is set as a cone, and the length of the traction weight is 50cm-100cm, the diameter is 70cm-100mm, and the mass is 60kg-100kg.
[0110] Specifically, in order to ensure that the traction hammer can be smoothly driven into the bottom of the deep micro-logging well, this embodiment sets one end of the traction hammer to be conical, and sets the length of the traction hammer to 50cm-100cm, the diameter to 70cm-100mm, and the mass to 60kg-100kg. For example... Figure 6 The diagram shown is a schematic of a traction weight provided in this embodiment.
[0111] In another embodiment, the receiving device includes: a plurality of detectors and a cable;
[0112] The detector includes a detector head and connecting wires;
[0113] Each of the detectors is distributed on the cable at a preset distance, and the connecting lines of each detector are fixedly connected to the cable.
[0114] Specifically, the receiving device includes multiple detectors and cables. Each detector includes a detector head and a connecting wire. To prevent the detectors from receiving cable waves propagating from the cable, this embodiment fixes the connecting wires of the detectors to the cables, rather than connecting the detector heads of the detectors to the cables. Preferably, the connection method is to use cable ties. Each detector is connected to the cable according to the above connection method, and during connection, each detector must be distributed on the cable at a predetermined distance.
[0115] In another embodiment, one end of the cable is connected to the traction weight, and the other end is connected to the shallow refractometer.
[0116] Specifically, in order to ensure that each receiver in the receiving device can smoothly enter the deep micro-logging well, one end of the cable in the receiving device is connected to a traction weight, so that the gravity of the traction weight can bring each receiver in the receiving device into the deep micro-logging well. At the same time, in order to ensure that the deep micro-logging data generated by the detector can be acquired by the shallow refractometer, this embodiment also connects the other end of the cable in the receiving device to the shallow refractometer.
[0117] In addition, to better illustrate the above embodiments of this application, the following examples are provided for explanation:
[0118] In a 3D seismic exploration and acquisition project in the complex mountainous region of southwestern Tarim Basin, deep micro-logging surveys were conducted in the Gobi gravel area, with depths of 288m, 316m, and 492m. The deep micro-logging survey method proposed in this application was used to investigate these three deep micro-logging wells. Taking the 492m deep micro-logging well as an example, the implementation is as follows:
[0119] Preparations for conducting deep micro-logging surveys include: making a portable micro-vibration source, processing a traction hammer, making a receiving device that connects the detector to the cable, and purchasing well sealing backfill materials and wire ropes.
[0120] After drilling to the designed depth of 492m, cementing was performed using cementing agent. Water was then injected into the well to dilute the drilling mud. While keeping the drill bit operational, it was raised from the bottom to the wellhead and then drilled back down, a process repeated to ensure a clean, unobstructed wellbore, smooth well walls, no collapse, and no falling debris. A traction receiving device was then lowered into the well using a traction hammer. After ensuring the receiving point met the design requirements (Table 1), backfill material was used to seal the well. The traction hammer was placed at the bottom of the receiving device, and a steel cable was securely attached to it. With the steel cable bearing the weight, the traction hammer pulled the receiving device into the well until the depth of the last receiving point reached the design requirements. The well was carefully sealed using purchased smooth, non-angular backfill material. To ensure effective sealing, the sealing process was carried out gradually. After filling the well with some backfill material, it was necessary to wait for it to sink completely to the deepest point before adding more backfill material. Because the well depth in this embodiment is 492m, the well sealing time is relatively long, and the entire well sealing process takes 24 hours.
[0121] Table 1 is as follows:
[0122]
[0123] Connect the shallow refractometer to detectors at channels 1 to 24 at the bottom of the well (the shallow refractometer used in this study has a maximum of 24 receiving channels). Excite the portable microseismic source at a distance of 4m from the wellhead on the surface, and collect micrologging data from channels 1 to 24 at the bottom of the well. Connect the shallow refractometer to channels 24 (which overlaps with the last channel from the first acquisition) to 47 at the bottom of the well. Excite the portable microseismic source again at the same location 4m from the wellhead on the surface, and collect micrologging data from channels 24 to 47 at the bottom of the well. Repeat this process (until all deep micrologging data is collected).
[0124] In this embodiment, the well depth was 492m, and a total of 100 channels were received. The micrologging data acquisition was completed after the portable microsource was excited on the surface a total of 5 times. The channels corresponding to the repeated detectors for data acquisition between different seismic events were channels 24, 47, 70 and 93.
[0125] The reception times of the 24th channel triggered by the first earthquake and the 24th channel triggered by the second earthquake are t and t, respectively. 1(24) =132.61ms and t 2(24) =132.65ms, then the system time difference between the second excitation and the first excitation is: Δt 21 =t 2(24) -t 1(24)=132.65-132.61=0.04ms.
[0126] The reception times of the 47th channel triggered by the second earthquake and the 47th channel triggered by the third earthquake were t and t, respectively. 2(47) =96.46ms and t 3(47) = 96.46 ms, then the system time difference between the 3rd excitation and the 2nd excitation is:
[0127] Δt 32 =t 3(47) -t 2(47) =96.46-96.46=0.00ms.
[0128] The reception times of the 70th channel triggered by the 3rd earthquake and the 70th channel triggered by the 4th earthquake were t and t, respectively. 3(70) =50.39ms and t 4(70) = 50.37ms, then the system time difference between the 4th excitation and the 3rd excitation is:
[0129] Δt 43 =t 4(70) -t 3(70) =50.37-50.39=-0.02ms.
[0130] The reception times of the 93rd channel triggered by the 4th earthquake and the 93rd channel triggered by the 5th earthquake were t and t, respectively. 4(93) =16.41ms and t 5(93) =16.45ms, then the system time difference between the 5th excitation and the 4th excitation is:
[0131] Δt 54 =t 5(93) -t 4(93) =16.45-16.41=0.04ms.
[0132] The first arrival time of the first earthquake does not need to be corrected.
[0133] The corrected first-arrival propagation times for receivers at different depths during the second excitation are:
[0134] T 2(i) =t 2(i) -Δt 21
[0135] The corrected first-arrival propagation times for receivers at different depths during the third excitation are:
[0136] T 3(j) =t 3(j) -Δt 21 -Δt 32
[0137] The corrected first-arrival propagation times for receivers at different depths during the fourth excitation are:
[0138] T 4(k) =t 4(k) -Δt 21 -Δt 32 -Δt 43
[0139] The corrected first-arrival propagation times for receivers at different depths during the 5th excitation are:
[0140] T 5(l) =t 5(l) -Δt 21 -Δt 32 -Δt 43 -Δt 54
[0141] In the formula: t 2(i) t 3(j) t 4(k) t 5(l) , represents the reception time (ms) at a certain uncorrected receiving depth after the excitation of the 2nd, 3rd, 4th, and 5th earthquakes; i, j, k, and l are the number of receiving channels for a certain earthquake, dimensionless, with i ranging from 24 to 47; j ranging from 47 to 70; k ranging from 70 to 93; and l ranging from 93 to 100.
[0142] The process of correcting the reception time is illustrated using the 5th earthquake, with a reception depth of 6m and 98 reception channels as a specific example.
[0143] The reception time for the 5th earthquake, with a receiving depth of 6m and 98 channels, is 10.76ms. Therefore, the corrected first-arrival propagation time is:
[0144] T 5(98) =t 5(98) -Δt 21 -Δt 32 -Δt 43 -Δt 54
[0145] =10.76-0.04-0.00-(-0.02)-0.04
[0146] =10.70 (ms)
[0147] This process continues until the first-arrival propagation times for all earthquakes and all receiver channels have been corrected. Details of the corrected first-arrival propagation times for different earthquakes, receiver depths, and channel numbers are provided in Table 2. (See Table 2 for details.)
[0148]
[0149] For the corrected first-arrival propagation time, based on the offset distance between the portable microsource and the wellhead and different receiving depths, it can be converted into an expression for the one-way vertical propagation time as follows:
[0150]
[0151] Among them, t 0i t represents the one-way vertical propagation time for different receiving channels. i denoted as , where is the initial propagation time for different receiver channels; H is the receiving depth corresponding to different receiver channels; D is the offset distance between the portable microseismic source and the wellhead; and i is the receiver channel number counted from the bottom of the well.
[0152] Let's take the data from the 5th seismic event, with a receiving depth of 6m and 98 channels, as an example to illustrate the vertical propagation time correction method. The corrected first-arrival propagation time for this channel is 10.70ms. The offset distance between the portable microsource and the wellhead is 4m. Therefore, the one-way vertical propagation time is:
[0153]
[0154] Substituting all corrected first-arrival propagation times into the one-way vertical propagation time calculation expression, we obtain the one-way vertical propagation times for different reception depths, as detailed in Table 3. (See Table 3 for details.)
[0155]
[0156] A Cartesian coordinate system can be established with time as the horizontal axis and reception depth as the vertical axis. By placing different reception depths and their corresponding one-way vertical propagation time data into the Cartesian coordinate system, it is possible to analyze shallow and deep surface structures, such as... Figure 4 As shown.
[0157] Perform inconsistency correction on the excitation wavelet used for Q-value calculation:
[0158] Using the data from the second excitation and channel 24 as the data to be corrected, and the data from the first excitation and channel 24 as the specified desired output data, a shaping filter factor is calculated using the Wiener filtering method within a certain time and space range. This operator is then applied to the data to be corrected, thereby eliminating the difference between the data and the specified desired output data. Applying this operator to channels 24 to 47 during the second excitation eliminates the inconsistency of the excitation wavelet between the first and second excitations.
[0159] The data received at channel 47 during the third excitation was used as the data to be corrected. The data received at channel 47 during the second excitation, after eliminating the inconsistency of the excitation wavelet between the first and second excitations, was used as the specified desired output data. Within a certain time and space range, the Wiener filtering method was used to calculate the shaping filter factor, and then this operator was applied to the data to be corrected, thereby eliminating the difference between the data and the specified desired output data. This operator was applied to channels 47 to 70 during the third excitation, thereby eliminating the inconsistency of the excitation wavelet between the second and third excitations.
[0160] The data received at channel 70 during the fourth excitation was used as the data to be corrected. The data received at channel 70 during the third excitation, after eliminating the inconsistency of the excitation wavelet between the second and third excitations, was used as the specified desired output data. Within a certain time and space range, the Wiener filtering method was used to calculate the shaping filter factor, and then this operator was applied to the data to be corrected, thereby eliminating the difference between the data and the specified desired output data. This operator was applied to channels 70 to 93 during the fourth excitation, thereby eliminating the inconsistency of the excitation wavelet between the third and fourth excitations.
[0161] The data received at channel 93 during the 5th excitation was used as the data to be corrected. The data received at channel 93 during the 4th excitation, after eliminating the inconsistency of the excitation wavelet between the 3rd and 4th excitations, was used as the specified desired output data. Within a certain time and space range, the Wiener filtering method was used to calculate the shaping filter factor, and then this operator was applied to the data to be corrected, thereby eliminating the difference between the data and the specified desired output data. This operator was applied to channels 93 to 100 during the 5th excitation, thereby eliminating the inconsistency of the excitation wavelet between the 4th and 5th excitations.
[0162] For all seismic waves and all receiver channel data after non-uniform correction of the excited wavelet, the Q value can be calculated using the centroid frequency shift method (e.g., Figure 5 (As shown).
[0163] The above steps complete the entire process of deep micro-logging investigation.
[0164] The deep micro-logging investigation method and system provided in this application embodiment utilizes a self-made portable micro-seismic source, a fabricated hammer, and a receiving device that connects the geophone and cable. This system eliminates the need for explosives in the construction process, thus avoiding safety hazards, practicing "green exploration," avoiding the redundant time required for approval procedures, saving on explosives consumables, and avoiding high transportation and storage costs. The deep micro-logging investigation method uses a repeating geophone and corrects the receiving time of the receiver channel using two sets of data generated by the repeating geophone. This allows for a more accurate velocity model reflecting geological conditions, and the Q-value is calculated to determine the degree of seismic wave absorption and attenuation in the formation.
[0165] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.
[0166] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.
[0167] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0168] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes that element.
[0169] The above provides a detailed description of the deep micro-logging investigation method and system provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A method for investigating deep micro-logging, characterized in that, The method includes: The portable micro-vibration source is controlled to perform the Nth excitation, and the deep micro-logging data generated by the Nth geophone group is acquired sequentially from the bottom of the well to the wellhead. The deep micro-logging data includes the reception time of the corresponding receiving channel of each geophone in the geophone group. Using the received time of the receiving channel corresponding to the repeating detector in the previous detector group after correction, the received time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the received time of each receiving channel in the next detector group after correction. The repeating detector is the last detector in the detector group, and the last detector in the previous detector group is the same as the first detector in the next adjacent detector group. The receiving time of the corresponding receiving channel of the calibrated detector is determined as the corresponding first arrival propagation time; The one-way vertical propagation time of each receiver channel in the deep micro-logging data is obtained by calculating the first arrival propagation time, the offset distance between the portable micro-source and the wellhead, and the receiving depth of each receiver channel in the deep micro-logging data. Based on the one-way vertical propagation time and receiving depth of each receiving channel in the deep micro-logging data, the corresponding deep micro-logging time curves are plotted. A velocity model is constructed based on the deep micro-logging time curves.
2. The deep micro-logging investigation method according to claim 1, characterized in that, When the previous detector group is the first detector group, the receiving times of each receiving channel in the next detector group adjacent to the previous detector group are corrected using the receiving time of the receiving channel corresponding to the repeating detector in the previous detector group after correction, to obtain the corrected receiving time of each receiving channel in the next detector group, including: Using the reception time of the receiving channel corresponding to the repeating detector in the first detector group, the reception time of each receiving channel in the next detector group adjacent to the first detector group is corrected to obtain the corrected reception time of each receiving channel in the next detector group.
3. The deep micro-logging investigation method according to claim 1, characterized in that, Using the corrected reception time of the receiving channel corresponding to the repeating detector in the previous detector group, the reception time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the corrected reception time of each receiving channel in the next detector group, including: The corrected time difference is obtained by subtracting the receiving time of the receiving channel corresponding to the repeating detector in the previous detector group after correction from the receiving time of the receiving channel corresponding to the first detector in the next detector group adjacent to the previous detector group. Based on the corrected time difference, the reception time of each receiving channel in the next detector group adjacent to the previous detector group is corrected to obtain the corrected reception time of each receiving channel in the next detector group.
4. The deep micro-logging investigation method according to claim 1, characterized in that, By calculating the first-arrival propagation time of each receiver channel in the deep micrologging data, the offset distance between the portable microsource and the wellhead, and the receiving depth of each receiver channel in the deep micrologging data, the one-way vertical propagation time of each receiver channel in the deep micrologging data is obtained, including: The first arrival propagation time of each receiver channel in the deep micro-logging data, the offset distance between the portable micro-source and the wellhead, and the receiving depth of each receiver channel in the deep micro-logging data are substituted into the single-way vertical propagation time algorithm to obtain the single-way vertical propagation time of each receiver channel in the deep micro-logging data. The expression for the one-way vertical propagation time algorithm is as follows: Among them, t 0i t represents the one-way vertical propagation time for different receiving channels. i denoted as , where is the initial propagation time for different receiver channels; H is the receiving depth corresponding to different receiver channels; D is the offset distance between the portable microseismic source and the wellhead; and i is the receiver channel number counted from the bottom of the well.
5. The deep micro-logging investigation method according to claim 1, characterized in that, The method further includes: The data generated by the repeating detector in the previous detector group is determined as the desired output data, and the data generated by the first detector in the next detector group adjacent to the previous detector group is determined as the data to be corrected. The shaping filter factor between the desired output data and the data to be corrected is determined by Wiener filtering. Based on the shaping filter factor, the data received by each detector in the next detector group adjacent to the previous detector group are subjected to excitation wavelet inconsistency correction processing to obtain the target data corresponding to each detector. The target data is processed by the centroid frequency shift method to obtain the Q value corresponding to the velocity in the formation corresponding to each detector. The degree of absorption and attenuation of seismic waves in the strata is determined based on the Q value corresponding to the velocity in the strata corresponding to each detector.
6. A deep micro-logging survey system, characterized in that, The deep micro-logging investigation system is used to conduct deep micro-logging investigations using the deep micro-logging investigation method according to any one of claims 1 to 5. The system includes: a portable micro-vibration source, a receiving device, a traction weight, and a shallow refractometer. The portable microseismic source is used to perform multiple source excitations and generate seismic waves; The receiving device is used to receive seismic waves generated by a portable microseismic source and generate deep micro-logging data; The traction weight is used to pull the receiving device into the deep micro-logging well; The shallow refractometer is used to analyze and process the deep micro-logging data.
7. The deep micro-logging investigation system according to claim 6, characterized in that, The portable micro-vibration source includes multiple springs, and the number of springs increases accordingly with the depth of the deep micro-logging.
8. The deep micro-logging investigation system according to claim 6, characterized in that, One end of the traction weight is tapered, and the length of the traction weight is 50cm-100cm, the diameter is 70cm-100mm, and the mass is 60kg-100kg.
9. The deep micro-logging investigation system according to claim 6, characterized in that, The receiving device includes: multiple detectors and cables; The detector includes a detector head and connecting wires; Each of the detectors is distributed on the cable at a preset distance, and the connecting lines of each detector are fixedly connected to the cable.
10. The deep micro-logging investigation system according to claim 9, characterized in that, One end of the cable is connected to the traction weight, and the other end is connected to the shallow refractometer.