Underground sound wave remote detection method, system and device and nonvolatile storage medium

Abstract

The invention discloses an underground sound wave remote detection method, system and device and a nonvolatile storage medium. The method comprises the following steps: transmitting a first optical signal to an underground formation environment; in response to triggering of sound source equipment located in the underground stratum environment, a second optical signal obtained by reflection of a weak grating fiber in the underground stratum environment based on the first optical signal is received, and the weak grating fiber is used for receiving a second sound wave signal and sending the second sound wave signal to the sound source equipment; the second sound wave signal is a sound wave signal obtained by reflecting the first sound wave signal generated by the sound source equipment through an underground stratum; demodulating the second optical signal to obtain a second sound wave signal received by the weak grating fiber; and stratum information of the underground stratum is obtained according to the second sound wave signal. The technical problem that an existing underground remote detection method is low in reliability is solved.

Description

Technical Field

[0001] The present invention relates to the field of geophysical logging, and in particular, to a downhole acoustic far-detection method, system, device, and non-volatile storage medium. Background Art

[0002] With the extension of oil and gas exploration to deep / ultra-deep and complex fields, more stringent requirements are put forward for logging far-detection instruments. The requirements for temperature resistance, pressure resistance, and small size are further improved. Conventional electrical method acoustic far-detection systems face bottlenecks such as complex systems, low reliability, electromagnetic interference, limited data transmission capabilities, difficulty in further miniaturization, and limited improvement in high-temperature and high-pressure resistance. Moreover, it is difficult to improve the temperature resistance and pressure resistance of traditional electrical method instruments, and it is difficult to further miniaturize the instrument size, making it difficult to meet the actual production needs.

[0003] The currently adopted conventional fiber-optic downhole acoustic detection uses ordinary optical fibers based on the traditional Rayleigh scattering principle, which can obtain certain acoustic signals, but there are situations of low spatial sampling rate, low sensitivity, and low reliability. Especially for long-distance detection, there is a bottleneck of low signal-to-noise ratio, which restricts the popularization and application of fiber-optic acoustic logging technology. Therefore, it is very important to develop an acoustic far-detection instrument with a simple and reliable structure, high sensitivity, high temperature and high pressure resistance, and capable of meeting long-distance remote monitoring.

[0004] Aiming at the technical problem of low reliability of the existing downhole far-detection method, no effective solution has been proposed yet. Summary of the Invention

[0005] Embodiments of the present invention provide a downhole acoustic far-detection method, system, device, and non-volatile storage medium to at least solve the technical problem of low reliability of the existing downhole far-detection method.

[0006] According to one aspect of the embodiments of the present invention, a downhole acoustic far-detection method is provided, including: transmitting a first optical signal to the downhole formation environment; in response to triggering a sound source device located in the downhole formation environment, receiving a second optical signal reflected based on the first optical signal by a weak grating optical fiber in the downhole formation environment, where the weak grating optical fiber is used to receive a second acoustic signal, and the second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the sound source device by the downhole formation; demodulating the second optical signal to obtain the second acoustic signal received by the weak grating optical fiber; and obtaining formation information of the downhole formation according to the second acoustic signal.

[0007] According to another aspect of the embodiments of the present invention, there is also provided a downhole acoustic far-detection system, including: a downhole acoustic far-detection device, the downhole acoustic far-detection device includes a sound source device located in the downhole formation environment and a weak grating optical fiber located in the downhole formation environment, the sound source device is used to trigger a first acoustic signal, the weak grating optical fiber is used to reflect and generate a second optical signal according to a second acoustic signal and a first optical signal, and the second acoustic signal is an acoustic signal obtained by reflecting the first acoustic signal generated by the sound source device through the downhole formation; a target optoelectronic composite cable, the target optoelectronic composite cable is used to transmit the first optical signal to the downhole formation environment, and is used to transmit the second optical signal to a control device; the control device, the control device is used to trigger the sound source device located in the downhole formation environment, and is used to receive the second optical signal reflected by the weak grating optical fiber in the downhole formation environment based on the first optical signal, and is used to demodulate the second optical signal to obtain the second acoustic signal received by the weak grating optical fiber, and to obtain formation information of the downhole formation according to the second acoustic signal.

[0008] According to still another aspect of the embodiments of the present invention, there is also provided a downhole acoustic far-detection device, including: a transmission unit, configured to transmit a first optical signal to the downhole formation environment; a response unit, configured to respond to triggering a sound source device located in the downhole formation environment, and receive a second optical signal reflected by a weak grating optical fiber in the downhole formation environment based on the first optical signal, wherein the weak grating optical fiber is used to receive a second acoustic signal, and the second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the sound source device through the downhole formation; a demodulation unit, configured to demodulate the second optical signal to obtain the second acoustic signal received by the weak grating optical fiber; an acquisition unit, configured to obtain formation information of the downhole formation according to the second acoustic signal.

[0009] Optionally, the downhole acoustic far-detection device further includes a winding unit, configured to wind the weak grating optical fiber on the surface of a sensitizing substrate to obtain a plurality of sensing receiving units before receiving the second optical signal reflected by the weak grating optical fiber in the downhole formation environment, wherein a grating array with low reflectivity etched at equal intervals is included on the weak grating optical fiber; a forming unit, configured to form an array detector according to the plurality of sensing receiving units; a first layout unit, configured to layout the array detector in the downhole formation environment.

[0010] Optionally, the forming unit includes a connecting unit for connecting the sensing receiving unit through the weak grating optical fiber to obtain a sensing receiving unit array; a second laying unit for laying a support skeleton and laying a transmission cable between the sensing receiving units in the sensing receiving unit array; a connecting unit for connecting the support skeleton and the sensing receiving units in the sensing receiving unit array in series by using a tensile rope and sleeving an outer sleeve; a filling unit for filling the outer sleeve with a target filler to obtain the array detector, where the target filler is used to exclude gas in the outer sleeve and improve acoustic wave coupling at the same time.

[0011] Optionally, the response unit includes a first obtaining unit for obtaining the backward Rayleigh scattered optical signal included in the second optical signal, where the weak grating optical fiber is used to generate the backward Rayleigh scattered optical signal according to the first optical signal; the first obtaining unit is further used to obtain the second optical signal transmitted through the target optoelectronic composite cable.

[0012] Optionally, the transmission unit includes a transmission subunit for transmitting the first optical signal to the downhole formation environment through a target optoelectronic composite cable.

[0013] Optionally, the downhole acoustic wave long-distance detection device further includes a second obtaining unit for obtaining acoustic wave control parameters before responding to triggering a sound source device located in the downhole formation environment and receiving a second optical signal reflected based on the first optical signal by the weak grating optical fiber in the downhole formation environment; a triggering unit for triggering the sound source device located in the downhole formation environment according to the acoustic wave control parameters.

[0014] Optionally, the obtaining unit includes an obtaining subunit for obtaining the formation information of the downhole formation according to the first acoustic wave signal and the second acoustic wave signal indicated by the acoustic wave control parameters.

[0015] According to another aspect of the embodiments of the present invention, there is also provided a non-volatile storage medium, and the non-volatile storage medium includes a stored program, where when the program runs, it controls the device where the non-volatile storage medium is located to execute any one of the above downhole acoustic wave long-distance detection methods.

[0016] According to still another aspect of the embodiments of the present invention, there is also provided a computer device, and the computer device includes a processor for running a program, where when the program runs, it executes any one of the above downhole acoustic wave long-distance detection methods.

[0017] In an embodiment of the present invention, a downhole acoustic far-detection method is adopted. A first optical signal is transmitted to the downhole formation environment; in response to triggering a sound source device located in the above-mentioned downhole formation environment, a second optical signal reflected based on the first optical signal by a weak grating optical fiber in the above-mentioned downhole formation environment is received, wherein the weak grating optical fiber is used to receive a second acoustic wave signal, and the second acoustic wave signal is an acoustic wave signal obtained by reflecting a first acoustic wave signal generated by the sound source device through the downhole formation; the second optical signal is demodulated to obtain the second acoustic wave signal received by the weak grating optical fiber; formation information of the downhole formation is obtained according to the second acoustic wave signal, achieving the technical effect of improving the reliability of the downhole acoustic far-detection method and solving the technical problem of low reliability of the existing downhole far-detection method. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and the schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0019] Figure 1 A structural block diagram of a downhole acoustic far-detection system for implementing the downhole acoustic far-detection method is shown;

[0020] Figure 2 is a flowchart of a downhole acoustic far-detection method provided according to an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram of a downhole acoustic far-detection method provided according to an embodiment of the present invention;

[0022] Figure 4 is a flowchart of another downhole acoustic far-detection method provided according to an embodiment of the present invention;

[0023] Figure 5 is a schematic diagram of another downhole acoustic far-detection method provided according to an embodiment of the present invention;

[0024] Figure 6 is a schematic structural diagram of a downhole acoustic far-detection device provided according to an embodiment of the present invention;

[0025] Figure 7 is a schematic structural diagram of an electronic device provided according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] To enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solution in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order different from those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0028] According to an embodiment of the present invention, an embodiment of an underground acoustic far-detection method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that here.

[0029] The method embodiment provided in the first embodiment of the present application can control the system through a terminal device to implement the underground acoustic far-detection method. Figure 1 The structural block diagram of an underground acoustic far-detection system for implementing the underground acoustic far-detection method is shown. As Figure 1 shown, the underground acoustic far-detection system mainly includes a ground demodulation system (i.e., the above-mentioned control device), a transmission system (the transmission system is composed of the above-mentioned target optoelectronic composite cable), and an underground system (i.e., the underground acoustic far-detection device included in the above-mentioned underground acoustic far-detection system. To distinguish it from the underground acoustic far-detection device in the independent claim, the underground acoustic far-detection device included in the underground acoustic far-detection system will be referred to as the underground system hereinafter). The underground acoustic far-detection method implemented by the underground acoustic far-detection system shown above specifically includes the following steps: Figure 1 shown above specifically includes the following steps:

[0030] S1, transmitting a first optical signal to the underground formation environment;

[0031] S2, in response to triggering a sound source device located in the underground formation environment (such asFigure 1 The excitation sound source shown in the figure) receives a second light signal obtained by reflecting the first light signal based on the weak grating optical fiber in the downhole formation environment, wherein the weak grating optical fiber is used to receive a second sound wave signal, and the second sound wave signal is a sound wave signal obtained by reflecting the first sound wave signal generated by the sound source device through the downhole formation;

[0032] S3, demodulating the second optical signal to obtain a second acoustic wave signal received by the weak grating optical fiber;

[0033] S4, obtaining the formation information of the underground formation according to the second acoustic wave signal.

[0034] If Figure 1 As shown in , the downhole acoustic wave remote detection system includes Figure 1 The ground demodulation system, transmission system and downhole system shown in the figure, the ground demodulation system includes an excitation sound source control system (used to control the downhole excitation sound source to emit sound wave signals according to specific parameters) and a signal demodulation system (used to demodulate the sound wave vibration signal obtained by the downhole array detector, that is, the second sound wave signal), the transmission system includes an optoelectronic composite cable, the downhole system includes a faucet, a connector connecting the faucet and the array detector, an array detector, a connector connecting the array detector and the excitation sound source, and an excitation sound source, the optical fiber in the optoelectronic composite cable can be a single-mode optical fiber or a multi-mode optical fiber, and can be an ordinary optical fiber or a weak grating optical fiber, such as Figure 1 The excitation sound source control system and the signal demodulation system shown are synchronously controlled to demodulate the backscattered Rayleigh scattered light signal (second light signal) reflected by the first light signal in the weak grating fiber.

[0035] If Figure 1 The main systems included in the downhole acoustic wave remote detection system shown in are as follows Figure 1 The ground demodulation system, transmission system and downhole system shown in the figure, in the process of implementing the downhole acoustic wave remote detection method, the above-mentioned ground demodulation system, transmission system and downhole system respectively include the following components and the specific operations performed:

[0036] Downhole acoustic wave long-distance detection device (i.e., the above-mentioned downhole system), the downhole acoustic wave long-distance detection device (i.e., the above-mentioned downhole system) includes a sound source device located in a downhole formation environment and a weak grating optical fiber located in a downhole formation environment, the sound source device is used to trigger a first acoustic wave signal, the weak grating optical fiber is used to generate a second optical signal according to a second acoustic wave signal and the reflection of the first optical signal, the second acoustic wave signal is an acoustic wave signal obtained by reflecting the first acoustic wave signal generated by the sound source device through the downhole formation;

[0037] Target optoelectronic composite cable, the target optoelectronic composite cable is used to transmit the first optical signal to the downhole formation environment, and is used to transmit the second optical signal to the control device (i.e. the above-mentioned ground demodulation system);​​

[0038] The control device (i.e., the above-mentioned ground demodulation system) is used to trigger a sound source device located in the downhole formation environment, and to receive a second optical signal reflected based on a first optical signal by a weak grating optical fiber in the downhole formation environment, and to demodulate the second optical signal to obtain a second acoustic signal received by the weak grating optical fiber, and to obtain formation information of the downhole formation according to the second acoustic signal.

[0039] Through the downhole acoustic far detection system as Figure 1 shown, the above-mentioned downhole acoustic far detection method is implemented. The method includes transmitting a first optical signal to the downhole formation environment; in response to triggering a sound source device located in the above-mentioned downhole formation environment, receiving a second optical signal reflected based on the above-mentioned first optical signal by a weak grating optical fiber in the above-mentioned downhole formation environment, wherein the above-mentioned weak grating optical fiber is used to receive a second acoustic signal, and the above-mentioned second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the above-mentioned sound source device through the downhole formation; demodulating the above-mentioned second optical signal to obtain the above-mentioned second acoustic signal received by the above-mentioned weak grating optical fiber; and obtaining formation information of the above-mentioned downhole formation according to the above-mentioned second acoustic signal, achieving the technical effect of improving the reliability of the downhole acoustic far detection method and solving the technical problem of low reliability of the existing downhole far detection method.

[0040] The present invention will be described below in conjunction with preferred implementation steps. Figure 2 is a flowchart of a downhole acoustic far detection method provided by an embodiment of the present application. As Figure 2 shown, the method includes the following steps:

[0041] S202, transmit a first optical signal to the downhole formation environment.

[0042] S204, in response to triggering a sound source device located in the downhole formation environment, receive a second optical signal reflected based on a first optical signal by a weak grating optical fiber in the downhole formation environment, wherein the weak grating optical fiber is used to receive a second acoustic signal, and the second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the sound source device through the downhole formation.

[0043] S206, demodulate the second optical signal to obtain the second acoustic signal received by the weak grating optical fiber.

[0044] S208, obtain formation information of the downhole formation according to the second acoustic signal.

[0045] It should be noted that the first optical signal in S202 above can be, but is not limited to, understood as being generated by Figure 1The optical signal output by the ground demodulation system shown is transmitted through the optical and electrical composite cable in the transmission system to the initial optical signal in the weak grating optical fiber in the downhole system. The above-mentioned downhole formation environment includes various types, such as geological anomalies, fractures, oil and gas reservoirs, foreign objects, etc. The above-mentioned transmission of the first optical signal to the downhole formation environment includes: transmitting the first optical signal to the downhole formation environment through the target optical and electrical composite cable. The optical fiber in the above-mentioned optical and electrical composite cable can be a single-mode optical fiber or a multi-mode optical fiber, and can be an ordinary optical fiber or a weak grating optical fiber.

[0046] The sound source device in the above S204 is the excitation sound source as Figure 1 shown. The above sound source device can be a high-temperature and high-pressure resistant acoustic transducer; the operation of triggering the sound source device can be as Figure 1 shown. The ground demodulation system shown controls the excitation sound source in the downhole system through the excitation sound source control system, and controls the excitation sound source to emit a first acoustic signal with a preset frequency. After the excitation sound source emits the first acoustic signal, the first acoustic signal can obtain a second acoustic signal after being reflected by the downhole formation in the downhole formation environment. The second acoustic signal can cause the weak grating optical fiber in the array detector located in the downhole formation environment to vibrate, so that the backscattered Rayleigh light of the initial optical signal (i.e., the above-mentioned first optical signal) in the weak grating optical fiber changes; the above weak grating optical fiber is a weak grating array with low reflectivity etched at equal intervals on the optical fiber. The above-mentioned reception of the second optical signal reflected based on the first optical signal by the weak grating optical fiber in the downhole formation environment includes obtaining the second optical signal transmitted through the target optical and electrical composite cable.

[0047] The operation of demodulating the second optical signal in the above S206 can obtain the second acoustic signal. At the same time, demodulating the second optical signal can also determine the signal phase difference between the first optical signal and the second optical signal. According to the signal phase difference and the second acoustic signal, the position where the first acoustic signal is reflected (i.e., the starting position where the second acoustic signal is generated) can be determined.

[0048] The downhole acoustic far detection method provided by the embodiments of the present application adopts transmitting the first optical signal to the downhole formation environment; in response to triggering the sound source device located in the above-mentioned downhole formation environment, receiving the second optical signal reflected based on the above-mentioned first optical signal by the weak grating optical fiber in the above-mentioned downhole formation environment, where the above weak grating optical fiber is used to receive the second acoustic signal, and the above second acoustic signal is an acoustic signal obtained by reflecting the first acoustic signal generated by the above sound source device through the downhole formation; demodulating the above second optical signal to obtain the above second acoustic signal received by the above weak grating optical fiber; obtaining the formation information of the above downhole formation according to the above second acoustic signal, achieving the technical effect of improving the reliability of downhole acoustic far detection, and solving the technical problem of low reliability of the existing downhole acoustic far detection method.

[0049] As an optional solution, before receiving the second optical signal reflected based on the weak grating optical fiber in the downhole formation environment, it further includes:

[0050] S1. Wind the weak grating optical fiber on the surface of the sensitization substrate to obtain a plurality of sensing receiving units, wherein the weak grating optical fiber is provided with a grating array with low reflectivity etched at equal intervals;

[0051] S2. Form an array detector according to the plurality of sensing receiving units;

[0052] S3. Deploy the array detector into the downhole formation environment.

[0053] It should be noted that the weak grating optical fiber in the above S1 can be a weak grating optical fiber array obtained after etching a grating array with low reflectivity at equal intervals on the weak grating optical fiber. The above sensitization substrate can be a substrate that can increase the sensitivity of the weak grating optical fiber after winding, greatly simplifying the system composition and improving the reliability. That is, the above sensing receiving unit is made by winding the weak grating optical fiber on the sensitization material with a certain tension. Each sensing receiving unit includes at least two weak gratings. The shape of the substrate can be a cylindrical substrate, which can ensure that the weak grating optical fiber is wound in the close-packed winding area on the outer surface of the sensitization substrate, so that the weak grating optical fiber and the sensitization substrate can be closely attached. After etching a grating array with low reflectivity at equal intervals on the weak grating optical fiber to obtain a weak grating optical fiber array, the weak grating optical fiber array can be wound on the surface of the sensitization substrate, thereby obtaining a plurality of sensing receiving units. The above sensing receiving units are used to receive the second acoustic signal.

[0054] The sensing receiving unit in the above S2 is made by uniformly winding the weak grating optical fiber on the sensitization material with a certain tension. Each sensing receiving unit includes at least two weak gratings. The above sensing receiving unit is designed to be hollow, which is convenient for fiber routing and cable routing; the above array detector is a detector formed by winding the weak grating optical fiber on the surface of the sensitization substrate. The above detector can be, but is not limited to, understood as that after winding the weak grating optical fiber on the surface of the sensitization substrate, the weak grating optical fiber between every two weak gratings can be wound on the sensitization substrate to form a plurality of acoustic wave receiving loops. The plurality of acoustic wave receiving loops formed by winding the weak grating optical fiber between every two weak gratings on the sensitization substrate is one of the above sensing receiving units. The entire weak grating optical fiber includes a plurality of weak gratings. After the entire weak grating optical fiber is wound on the sensitization substrate, a plurality of sensing receiving units can be formed, and the array detector includes the above plurality of sensing receiving units.

[0055] Deploying the array detector into the downhole formation environment in the above S3 can be, but is not limited to, understood as that after forming the array detector, the array detector is connected through a transmission system as shown in Figure 1 shown and Figure 1After being connected to the shown ground demodulation system, the length of the transmission system can support placing the above-mentioned array detector into the downhole formation environment.

[0056] The winding pitch of the above-mentioned weak grating optical fiber can be adjusted according to actual applications to meet point-type, quasi-distributed, and distributed layouts. The winding substrate of the above-mentioned weak grating optical fiber can be selected from materials with a relatively high sound propagation speed, effectively separating the first acoustic signal and the second acoustic signal, and avoiding the interference of the first acoustic signal (direct acoustic wave) on the weak grating optical fiber.

[0057] The downhole acoustic far-detection method provided by the embodiments of the present application winds a weak grating optical fiber on the surface of a sensitization substrate to obtain a plurality of sensing and receiving units, where the weak grating optical fiber includes a grating array with low reflectivity etched at equal intervals; an array detector is formed according to the plurality of sensing and receiving units; and the array detector is arranged in the downhole formation environment, which can effectively avoid the interference of direct acoustic waves, improve the signal accuracy of the received second optical signal and the second acoustic signal, and thus improve the reliability of the above-mentioned downhole acoustic far-detection method.

[0058] As an optional solution, forming an array detector according to the plurality of sensing and receiving units includes:

[0059] S1, connecting the sensing and receiving units through the weak grating optical fiber to obtain an array of sensing and receiving units;

[0060] S2, arranging a support skeleton and arranging transmission cables between the sensing and receiving units in the array of sensing and receiving units;

[0061] S3, using a tensile rope to connect the support skeleton and the sensing and receiving units in the array of sensing and receiving units in series, and sleeving an outer casing;

[0062] S4, filling the outer casing with a target filler to obtain an array detector, where the target filler is used to exclude the gas in the outer casing.

[0063] It should be noted that the support skeleton in S2 above can be made of a high-strength and high-temperature-resistant composite material, the above-mentioned made skeleton is used to support the outer casing, and the above-mentioned outer casing can be made of a high-temperature-resistant and pressure-bearing composite material; the above-mentioned transmission cable is an Figure 1 as shown in the optical and electrical composite cable, the tensile rope in S3 above can be a tensile rope made of a high-temperature-resistant material, such as a Kevlar rope, a steel wire, etc., the tensile rope is used to connect and fix the sensing and receiving units, the target filler in S4 above can be a filler made of a material with high temperature resistance and good sound conduction effect, such as silicone oil, light paraffin oil, gel; the target filler is used to improve the coupling of acoustic signals and reduce the attenuation performance of acoustic wave conduction.

[0064] The downhole acoustic far-detection method provided by the embodiments of the present application connects the sensing and receiving units through a weak grating optical fiber to obtain a sensing and receiving unit array; a support skeleton is arranged between the sensing and receiving units in the sensing and receiving unit array, and a transmission cable is arranged; a tensile rope is used to connect the support skeleton and the sensing and receiving units in the sensing and receiving unit array in series, and an outer sleeve is sleeved; the outer sleeve is filled with a target filler to obtain an array detector, where the target filler is used to exclude the gas in the outer sleeve, and the limitation of various materials enables each device in the downhole acoustic far-detection system for implementing the above downhole acoustic far-detection method to work normally in the high-temperature environment downhole, ensuring the reliability of the above downhole acoustic far-detection method.

[0065] As an alternative solution, the above receiving the second optical signal reflected by the weak grating optical fiber based on the first optical signal in the downhole formation environment includes: obtaining the backward Rayleigh scattering optical signal included in the second optical signal, where the weak grating optical fiber is used to generate the backward Rayleigh scattering optical signal according to the first optical signal.

[0066] The downhole acoustic far-detection method provided by the embodiments of the present application obtains the backward Rayleigh scattering optical signal included in the second optical signal, where the weak grating optical fiber is used to generate the backward Rayleigh scattering optical signal according to the first optical signal. The backward Rayleigh scattering optical signal generated by the weak grating optical fiber for the first optical signal can effectively enhance the backward Rayleigh scattering optical signal generated by the first optical signal, thereby achieving the purpose of downhole long-distance detection.

[0067] As an alternative solution, before the above-mentioned triggering the sound source device located in the downhole formation environment and receiving the second optical signal reflected by the weak grating optical fiber based on the first optical signal in the downhole formation environment, it further includes:

[0068] S1, obtaining acoustic control parameters;

[0069] S2, triggering the sound source device located in the downhole formation environment according to the acoustic control parameters.

[0070] The acoustic parameters in the above S1 include the intensity of the acoustic signal and the frequency of the acoustic signal.

[0071] The downhole acoustic far-detection method provided by the embodiments of the present application obtains acoustic control parameters; triggers the sound source device located in the downhole formation environment according to the acoustic control parameters, and can emit a first acoustic signal with a fixed frequency according to the acoustic control parameters through the acoustic device, so as to accurately demodulate the second acoustic signal and the second optical signal formed by the reflection of the first optical signal in the weak grating optical fiber inside the above target detector under the action of the second acoustic signal effectively and reliably, improving the reliability of the above downhole acoustic far-detection method.

[0072] The following will combine with Figure 1 and Figures 3 to 4 to elaborate on the above-mentioned downhole acoustic far-detection method of this application in detail:

[0073] As Figure 1 shown in the downhole system (the above-mentioned downhole acoustic far-detection device), the components included are as Figure 3 shown. Specifically, it includes a tool joint 302 (made of high-temperature and pressure-resistant materials, with a cover plate design for convenient cable connection and fiber optic connection operations, used to connect the electro-optical composite cable and the first connector), a first connector 304 (used to connect the tool joint 302 and the array detector 306), an array detector 306, an outer sleeve 308 (made of high-temperature and pressure-resistant composite materials, used for pressure-bearing and protecting the array detector at the same time), a support skeleton 310 (made of high-strength and high-temperature-resistant composite materials, used to support the outer sleeve), a tensile rope 312 (made of high-temperature-resistant materials such as Kevlar ropes and steel wires, used to connect and fix the sensing and receiving units in series), and a second connector 314 (used to connect the array detector 306 and the Figure 1 excitation sound source shown (i.e., the above-mentioned sound source device, such as a high-temperature and high-pressure acoustic transducer)). The end faces of the above-mentioned first connector 304 and second connector 314 are provided with fiber optic and cable routing holes, which are respectively used for the fixed connection of fiber optic pressure-bearing pins and cable pressure-bearing pins. The first connector 304 and the second connector 314 are also provided with oil injection holes and exhaust holes up and down for filling the filler. One end of the first connector 304 and the second connector 314 is also designed with two protruding fixing claws with small holes for fixing the tensile rope.

[0074] The realization of the above-mentioned downhole acoustic far-detection method through the downhole acoustic far-detection system shown in Figure 1 is specifically as follows: The first optical signal transmitted by the ground demodulation system shown in Figure 1 is modulated and then transmitted to the downhole receiving array (the array detector in the downhole system shown in Figure 1 ) through the electro-optical composite cable; the first optical signal propagating in the fiber of the downhole receiving array will periodically generate enhanced backward Rayleigh scattering light (i.e., the second optical signal) through the weak grating array, and the Rayleigh scattering light is transmitted to the ground demodulation system shown in Figure 1 through the electro-optical composite cable, and the acoustic wave information of the environment where the weak grating of the downhole receiving array is located (i.e., the above-mentioned second acoustic wave signal) is obtained. The position information and the second acoustic wave signal can be obtained through demodulation, and the detection of formation information is realized.

[0075] The steps of realizing the above-mentioned downhole acoustic far-detection method through the downhole acoustic far-detection system composed of the downhole system shown in Figure 3 and the ground demodulation system and transmission system shown in Figure 1 are as Figure 4As shown in the figure, the specific steps are as follows:

[0076] S402, lay the weak grating optical fiber;

[0077] S402-1, wind the weak grating optical fiber;

[0078] S402-2, lay the transmission cable and the support skeleton;

[0079] S402-3, use the tensile rope to connect the support skeleton and the sensing receiving unit in series;

[0080] S402-4, install the outer sleeve pipe and fix it with a connector;

[0081] S402-5, add filler, remove air, and form an independent array detector.

[0082] The operation in the above S204-5 is specifically to add filler through the small holes of the connector (such as Figure 3 the first connector 304 and the second connector 314 shown in the figure), remove the air in the outer sleeve pipe, and form an independent array detector.

[0083] S404, connect the faucet, the second connector, the array detector and the excitation sound source to form a downhole system;

[0084] S406, turn on the ground demodulation system, set parameters, and the first optical signal enters the weak grating optical fiber in the array detector through the optoelectronic composite cable;

[0085] S408, the acoustic signal reflected by the formation foreign object changes the first optical signal in the weak grating optical fiber, generating modulated backward Rayleigh scattering light;

[0086] S410, the backward Rayleigh scattering light enters the ground demodulation system through the optoelectronic composite cable, and demodulates the second acoustic signal.

[0087] It should be noted that the above laying method of the weak grating optical fiber can be understood, but is not limited to, including the following operations: winding the weak grating optical fiber on the sensitizing material with uniform tension to form independent sensing receiving units; connecting the sensing receiving units through the weak grating optical fiber to form an array of sensing receiving units; sequentially laying the support skeleton among the sensing receiving units and laying the transmission cable (i.e., the optoelectronic composite cable in the transmission system as shown in Figure 1 the figure); using the tensile rope to connect the support skeleton and the sensing receiving unit to fix the relative position; passing the tensile rope connecting the support skeleton and the sensing receiving unit through the outer sleeve pipe as a whole and fixing it with a connector; adding filler through the small hole of the connector to remove the air in the outer sleeve pipe and form an independent array detector.

[0088] It should be noted that the steps in S402 to S410 above can be, but are not limited to, understood as the specific implementation steps of the following downhole acoustic long-range detection method: laying weak grating optical fibers, winding the weak grating optical fibers on the surface of a sensitizing substrate to form an array detector; connecting a pony head, a connector, the array detector, and an excitation sound source to form a downhole system (the downhole acoustic long-range detection device included in the above downhole acoustic long-range detection system); turning on the ground demodulation system and setting the working parameters of the excitation sound source control system and the signal demodulation system. The excitation sound source control system controls the acoustic transducer to emit acoustic signals with specific parameters through electrical signals; the modulated signal light of the demodulation system enters the weak grating optical fiber in the array detector through an optoelectronic composite cable; the acoustic signal emitted by the acoustic transducer (i.e., the above sound source device, which is also the excitation sound source as shown in Figure 1 propagates in the formation, and after being reflected by foreign objects, the acoustic wave is transmitted to the weak grating optical fiber in the array detector, changing the optical parameters in the weak grating optical fiber. After being reflected by the weak grating, enhanced backscattered Rayleigh scattered light after modulation is generated; the Rayleigh scattered light enters the demodulation system through the optoelectronic composite cable; the demodulation system demodulates the second acoustic signal received by the weak grating optical fiber on all the sensing and receiving units in the array detector.

[0089] The present invention organically combines the ground demodulation system and the downhole system through a transmission system to achieve high-sensitivity acoustic long-range detection. By writing a large number of weak grating arrays with specific reflectivities on the optical fiber, the reflectivity at specific positions in the optical fiber is increased, the backscattered Rayleigh scattered light signal is enhanced, and the signal-to-noise ratio of the detected acoustic wave is significantly improved; through material sensitization and structural sensitization, the change amount of the acoustic wave-induced optical fiber length is further increased, thereby improving the sensitivity of acoustic wave detection; the downhole sound source system and the receiving system are connected through a tensile rope and a signal control transmission path to achieve the integration of transmission and reception of the detection system; a high-temperature-resistant outer sleeve is used to protect the array detector to improve its downhole temperature resistance; a filler with high acoustic wave coupling performance is used to improve the coupling performance of the received acoustic wave signal; optical fiber transmission is adopted to achieve the integration of optical fiber sensing, meeting the requirements of high-speed and large-capacity data transmission; a large number of high-temperature-resistant composite materials are used in the system to achieve the effect of sound insulation by itself, avoiding the complex sound insulation design of traditional electrical exploration instruments; a high-strength tensile rope is used for connection to meet the requirement of hanging the downhole sound source by the system. The present invention has the characteristics of simple and reliable structure, high temperature and high pressure resistance, high detection sensitivity, high-speed and large-capacity data transmission, and meeting the requirements of small-diameter wellbore detection.

[0090] As an optional solution, the obtaining of the formation information of the downhole formation according to the second acoustic signal includes: obtaining the formation information of the downhole formation according to the first acoustic signal and the second acoustic signal indicated by the acoustic control parameters.

[0091] It should be noted that the phase difference between the first acoustic wave signal and the second acoustic wave signal can be determined based on the above first acoustic wave signal and the second acoustic wave signal. The time when the first acoustic wave signal is reflected to form the second acoustic wave signal and the reflection intensity can be determined based on the phase difference of the acoustic wave signals. Thus, the position information where the first acoustic wave signal is reflected can be determined according to the transmission speed of the acoustic wave signal and the time when the second acoustic wave signal is formed; the specific medium information (the medium that causes the acoustic wave to be emitted) detected underground can be determined based on the time when the first acoustic wave signal is reflected to form the second acoustic wave signal and the signal information of the second acoustic wave signal.

[0092] The downhole acoustic wave long-distance detection method provided by the embodiments of the present application can accurately determine whether a target medium to be detected exists in a target downhole according to the first acoustic wave signal and the second acoustic wave signal indicated by the acoustic wave control parameters, and can accurately determine the position information where the target medium is located in the case where the target medium exists in the target downhole.

[0093] The following combines specific embodiments and Figure 5 to illustrate the above downhole acoustic wave long-distance detection method:

[0094] The weak grating optical fiber is wound around the outer surface of a hollow cylindrical substrate with an outer diameter of 60 mm at a constant tension, and closely wound for 27 turns to form an independent sensing and receiving unit, ensuring that the middle sections of two weak grating optical fibers with a spacing of 5000 mm all fall within the closely wound area on the outer surface of the substrate.

[0095] The other end of the weak grating optical fiber is connected to a signal demodulation system.

[0096] The excitation sound source control system is connected to the acoustic wave transducer through a signal generator and a power amplifier.

[0097] The sensing and receiving unit and the acoustic wave transducer are placed in a water-filled pool at a distance of 1000 mm and submerged. The signal generator is used to control the sound source to emit a sine pulse acoustic wave signal with a frequency of 9 kHz and an interval of 500 ms.

[0098] Turn on the signal demodulation system to detect the backward Rayleigh scattered light detected by the sensing and receiving unit;

[0099] By demodulating the phase information of the backward Rayleigh scattered light, the second acoustic wave signal of the weak grating on the sensing and receiving unit is obtained, and then the position information is associated to realize the detection of the second acoustic wave signal. The demodulated second acoustic wave signal is as Figure 5 shown.

[0100] Through the above embodiments of the present application, by etching an array of weak gratings with a specific reflectivity in an ordinary optical fiber, the intensity of the backward Rayleigh scattered light is increased, and the intensity of the optical signal change caused by the change in the optical fiber length due to underground noise vibration is enhanced, significantly improving the sensitivity of the system to detect underground acoustic signals. By Figure 1 The implementation of the underground acoustic far-detection method through the underground acoustic far-detection system shown not only has a simple and reliable structure, high measurement sensitivity, supports arbitrary layout, but also meets the requirements of underground long-distance detection.

[0101] From the embodiments of the present application and Figure 5 the detection results of the second acoustic signal corresponding to the above embodiments shown, it can be seen that the above underground acoustic far-detection method of the present application can still accurately and clearly detect the second acoustic signal in the scenario of long-distance detection, facilitating the determination of the formation information of the underground formation based on the accurate and clear second acoustic signal, and improving the reliability of the underground acoustic far-detection method.

[0102] The above is only a detailed description of the specific implementation manners of the present invention, rather than a limitation of the present invention. Those skilled in the relevant technical fields, without departing from the principles and scope of the present invention, all substitutions, deformations, and improvements made are included within the protection scope of the present invention.

[0103] It should be noted that for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present invention is not limited by the described action sequences, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0104] Through the description of the above embodiments, those skilled in the art can clearly understand that the underground acoustic far-detection method according to the above embodiments can be implemented by means of software plus a necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0105] According to an embodiment of the present invention, there is also provided an underground acoustic far-detection device for implementing the above underground acoustic far-detection method, Figure 6It is a structural block diagram of an underground acoustic far-detection device provided according to an embodiment of the present invention. As Figure 6 shown, the underground acoustic far-detection device includes: a transmission unit 602, a response unit 604, a demodulation unit 606, and an acquisition unit 608. As Figure 6 shown, in the process of implementing the above underground acoustic far-detection method, the functions played by each unit are specifically as follows:

[0106] The transmission unit 602 is used to transmit the first optical signal to the underground formation environment;

[0107] The response unit 604 is used to respond to triggering a sound source device located in the above underground formation environment, and receive a second optical signal reflected based on the first optical signal by a weak grating optical fiber in the above underground formation environment. Among them, the above weak grating optical fiber is used to receive a second acoustic signal, and the second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the above sound source device through the underground formation;

[0108] The demodulation unit 606 is used to demodulate the above second optical signal to obtain the above second acoustic signal received by the above weak grating optical fiber;

[0109] The acquisition unit 608 is used to obtain formation information of the above underground formation according to the above second acoustic signal.

[0110] It should be noted here that the above transmission unit 602, response unit 604, demodulation unit 606, and acquisition unit 608 respectively correspond to steps S202 to step S208 in the embodiment. The examples and application scenarios implemented by multiple modules and the corresponding steps are the same, but are not limited to the content disclosed in the above embodiments.

[0111] An embodiment of the present invention can provide a computer device. Optionally, in this embodiment, the above computer device can be located in at least one network device among multiple network devices of a computer network. The computer device includes a memory and a processor.

[0112] Among them, the memory can be used to store software programs and modules, such as the program instructions / modules corresponding to the downhole acoustic far-detection method and system in the embodiments of the present invention. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory, that is, to implement the above-mentioned downhole acoustic far-detection method. The memory may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some instances, the memory may further include a memory remotely disposed relative to the processor, and these remote memories can be connected to the computer terminal through a network. Examples of the above network include but are not limited to the Internet, enterprise intranet, local area network, mobile communication network, and combinations thereof.

[0113] The processor can call the information and application programs stored in the memory through the transmission device to control each component in the downhole acoustic far-detection system to implement the following steps: transmitting a first optical signal to the downhole formation environment; in response to triggering a sound source device located in the above downhole formation environment, receiving a second optical signal reflected based on the first optical signal by a weak grating optical fiber in the above downhole formation environment, wherein the weak grating optical fiber is used to receive a second acoustic signal, and the second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the sound source device through the downhole formation; demodulating the second optical signal to obtain the second acoustic signal received by the weak grating optical fiber; and obtaining formation information of the downhole formation according to the second acoustic signal.

[0114] Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by a program instructing relevant hardware devices controlled by a terminal device. The program can be stored in a non-volatile storage medium, and the storage medium can include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, an optical disk, etc.

[0115] An embodiment of the present invention also provides a non-volatile storage medium. Optionally, in this embodiment, the non-volatile storage medium can be used to store data information related to the downhole acoustic far-detection method provided in the above embodiment, such as data information related to the first optical signal and the second optical signal respectively, and data information related to the first acoustic signal and the second acoustic signal respectively.

[0116] Optionally, in this embodiment, the non-volatile storage medium can be located in any one of the computer terminals in a computer terminal group in a computer network, or in any one of the mobile terminals in a mobile terminal group.

[0117] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for controlling each component in the downhole acoustic far-detection system to perform the following steps: transmitting a first optical signal to the downhole formation environment; in response to triggering a sound source device located in the above-mentioned downhole formation environment, receiving a second optical signal reflected based on the first optical signal by a weak grating optical fiber in the above-mentioned downhole formation environment, wherein the weak grating optical fiber is used to receive a second acoustic signal, and the second acoustic signal is an acoustic signal obtained by reflecting a first acoustic signal generated by the sound source device through the downhole formation; demodulating the second optical signal to obtain the second acoustic signal received by the weak grating optical fiber; and obtaining formation information of the downhole formation according to the second acoustic signal.

[0118] An embodiment of the present invention further provides an electronic device for implementing the above-mentioned downhole acoustic far-detection method. The electronic device may be a terminal device or a server as shown in Figure 7 . Taking this electronic device as an example, as shown in Figure 7 , the electronic device includes a memory 702 and a processor 704. A computer program is stored in the memory 702, and the memory 702 may but is not limited to include a transmission unit 602, a response unit 604, a demodulation unit 606, and an acquisition unit 608 in the above-mentioned downhole acoustic far-detection device. The processor 704 is configured to execute the above-mentioned downhole acoustic far-detection method through the computer program.

[0119] Optionally, those of ordinary skill in the art can understand that Figure 7 the structure shown is only schematic. The electronic device may also be a terminal device such as a smart phone (such as an Android phone, an iOS phone, etc.), a tablet computer, a handheld computer, and a Mobile Internet Device (MID), a PAD, etc. Figure 7 This does not limit the structure of the above-mentioned electronic device. For example, the electronic device may further include more or fewer components (such as a network interface, etc.) than those shown in Figure 7 , or have a different configuration from that shown in Figure 7 .

[0120] Among them, the memory 702 can be used to store software programs and modules, such as the program instructions / modules corresponding to the downhole acoustic far detection method and system in the embodiments of the present application. The processor 704 executes various functional applications and data processing by running the software programs and modules stored in the memory 702, that is, implements the above-mentioned downhole acoustic far detection method. The memory 702 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memories. In some instances, the memory 702 may further include a memory remotely disposed relative to the processor 704, and these remote memories may be connected to the terminal through a network. Examples of the above network include but are not limited to the Internet, enterprise intranet, local area network, mobile communication network, and combinations thereof.

[0121] Optionally, the above electronic device further includes a transmission device 706, and the transmission device 706 is used to receive or send data via a network. Specific examples of the above network may include a wired network and a wireless network. In one instance, the transmission device 706 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices and routers through a network cable, so as to communicate with the Internet or a local area network. In one instance, the transmission device 706 is a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0122] In addition, the above electronic device further includes: a display 708, which is used to display the above first optical signal, second optical signal, first acoustic signal, and second acoustic signal; and a connection bus 710, which is used to connect each module component in the above electronic device.

[0123] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0124] In the above embodiments of the present invention, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0125] In several embodiments provided in the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of the units can be a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of units or modules can be in an electrical or other form.

[0126] The unit described as a separation component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed over multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0127] In addition, each functional unit in various embodiments of the present invention may be integrated in a processing unit, may exist separately as individual physical units, or two or more units may be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0128] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, read-only memories (ROMs), random access memories (RAMs), mobile hard disks, magnetic disks, or optical discs that can store program codes.

[0129] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for long-distance detection of downhole acoustic waves, characterized in that: include: transmitting the first optical signal to a downhole formation environment; In response to triggering a sound source device located in the downhole formation environment, receiving a second optical signal obtained by reflecting the first optical signal through a weak grating optical fiber in the downhole formation environment, wherein the weak grating optical fiber is used to receive a second acoustic wave signal, and the second acoustic wave signal is an acoustic wave signal obtained by reflecting the first acoustic wave signal generated by the sound source device through the downhole formation; Demodulating the second optical signal to obtain the second acoustic wave signal received by the weak grating optical fiber; The formation information of the downhole formation is acquired according to the second acoustic wave signal.

2. The method according to claim 1, characterized in that Before receiving the second optical signal obtained by the weak grating optical fiber in the downhole formation environment based on the reflection of the first optical signal, the method further includes: Winding the weak grating optical fiber on the surface of the sensitization substrate to obtain a plurality of sensing receiving units, wherein the weak grating optical fiber includes a low-reflectivity grating array etched at equal intervals; Forming an array detector according to a plurality of the sensing receiving units; The array detector is deployed in the downhole formation environment.

3. The method according to claim 2, characterized in that Forming an array detector according to a plurality of the sensing receiving units comprises: The sensor receiving units are connected via the weak grating optical fiber to obtain a sensor receiving unit array; Arranging a support frame between the sensor receiving units in the sensor receiving unit array, and arranging a transmission cable; The support frame and the sensing receiving units in the sensing receiving unit array are connected in series by using a tensile rope, and then sleeved with an outer sleeve; The outer sleeve is filled with a target filler to obtain the array detector, wherein the target filler is used to remove the gas in the outer sleeve and improve the coupling of sound waves.

4. The method according to claim 2, characterized in that: The receiving of a second optical signal obtained by reflecting the first optical signal from the weak grating optical fiber in the downhole formation environment comprises: A backscattered Rayleigh light signal included in the second optical signal is acquired, wherein the weak grating optical fiber is used to generate the backscattered Rayleigh light according to the first optical signal.

5. The method according to claim 1, characterized in that The transmitting the first optical signal to the downhole formation environment comprises: transmitting the first optical signal to the downhole formation environment through a target optoelectronic composite cable; The receiving of the second optical signal obtained by the weak grating optical fiber in the downhole formation environment based on the reflection of the first optical signal includes: acquiring the second optical signal transmitted through the target optoelectronic composite cable.

6. The method according to claim 1, characterized in that In response to triggering a sound source device in the downhole formation environment, before receiving a second optical signal obtained by reflecting the first optical signal according to a weak grating optical fiber in the downhole formation environment, the method further includes: Get the sound wave control parameters; The sound source device located in the downhole formation environment is triggered according to the sound wave control parameter.

7. The method according to claim 6, characterized in that Acquiring the formation information of the downhole formation according to the second acoustic wave signal includes: The formation information of the underground formation is obtained according to the first acoustic wave signal and the second acoustic wave signal indicated by the acoustic wave control parameter.

8. A downhole acoustic wave remote detection system, characterized in that: include A downhole acoustic wave long-distance detection device, the downhole acoustic wave long-distance detection device comprising a sound source device located in a downhole formation environment and a weak grating optical fiber located in the downhole formation environment, the sound source device is used to trigger a first acoustic wave signal, the weak grating optical fiber is used to generate a second optical signal according to a second acoustic wave signal and the reflection of the first optical signal, the second acoustic wave signal is an acoustic wave signal obtained by reflecting the first acoustic wave signal generated by the sound source device through the downhole formation; a target optoelectronic composite cable, the target optoelectronic composite cable being used to transmit the first optical signal to the downhole formation environment, and being used to transmit the second optical signal to a control device; The control device is used to trigger the sound source device located in the downhole formation environment, and is used to receive the second light signal obtained based on the reflection of the first light signal by the weak grating optical fiber in the downhole formation environment, and is used to demodulate the second light signal to obtain the second sound wave signal received by the weak grating optical fiber, and obtain the formation information of the downhole formation based on the second sound wave signal.

9. A downhole acoustic wave long-range detection device, characterized in that: include: A transmission unit, used to transmit the first optical signal to a downhole formation environment; A response unit, configured to receive, in response to triggering a sound source device located in the downhole formation environment, a second light signal obtained by reflecting the first light signal from a weak grating optical fiber in the downhole formation environment, wherein the weak grating optical fiber is configured to receive a second sound wave signal, and the second sound wave signal is a sound wave signal obtained by reflecting the first sound wave signal generated by the sound source device via the downhole formation; A demodulation unit, used for demodulating the second optical signal to obtain the second acoustic wave signal received by the weak grating optical fiber; An acquisition unit is used to acquire the formation information of the downhole formation according to the second acoustic wave signal.

10. A non-volatile storage medium, characterized in that: The non-volatile storage medium includes a stored program, wherein when the program is executed, the device where the non-volatile storage medium is located is controlled to execute the method according to any one of claims 1 to 7.

11. A computer device, characterized in that: include: Memory and processor, The memory stores a computer program; The processor is used to execute the computer program stored in the memory, and when the computer program is run, the processor is enabled to execute the method according to any one of claims 1 to 7.

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