Dual-logging-mode optical fiber sensing sound wave detection device and control method thereof

Abstract

The invention relates to the field of geophysical logging, and discloses a dual-logging-mode optical fiber sensing sound wave detection device and a control method thereof. The dual-logging-mode optical fiber sensing sound wave detection device comprises a power supply module used for providing electric energy; the measurement control module is used for controlling the optical modulation and demodulation module to emit laser pulse signals; the emission circuit is used for providing an emission driving signal for the emission acoustic system according to the emission instruction sent by the measurement control module; the emission sound system is used for amplifying the emission driving signal and executing sound wave excitation operation; the receiving sound system is used for sensitizing the weak sound signal so as to enable an optical fiber in the receiving sound system to be disturbed, and then mechanical vibration of the weak sound signal is coupled into a scattered light signal of the laser pulse signal; and the optical modulation and demodulation module is used for transmitting a laser pulse signal to the optical fiber and demodulating the scattered light signal to obtain spectral data. The optical modulation and demodulation module is arranged in an underground device, so that the defect that the optical fiber is snapped due to large self weight of the composite cable can be avoided.

Description

Technical Field

[0001] This disclosure relates to the field of geophysical logging technology, and in particular to a dual-logging-mode fiber optic sensing acoustic detection device and its control method. Background Technology

[0002] Fiber optic acoustic sensing technology is a technique that uses optical fibers as sensing elements to detect acoustic signals by measuring changes in the optical signals within the fibers. This technology offers advantages such as resistance to electromagnetic interference, small size, light weight, tolerance to harsh environments, and high sensitivity, making it particularly suitable for complex geological environments such as oil well logging, and its applications in geophysical exploration are increasing.

[0003] Currently, commonly used fiber optic logging methods include two types: permanent installation and fiber optic cable insertion. In the permanent installation method, the optical fiber is laid against the inner wall of the casing or buried in the cement sheath to achieve permanent monitoring of oil, gas and water well production / injection, evaluation of unconventional oil and gas reservoir stimulation effects, and microseismic monitoring. In the fiber optic cable insertion method, the optical cable is lowered into the well to perform vertical seismic profile measurements and production logging.

[0004] Sonic logging is an important method in geophysical logging. In open-hole wells, it reflects formation lithology by measuring the P-wave and S-wave transit times (the reciprocals of sound wave velocity), which is used to calculate porosity and characterize various influences. However, existing fiber optic acoustic sensing technologies typically involve a significant distance between the source and the fiber optic sensor, ranging from hundreds to thousands of meters. While some existing technologies offer fiber optic acoustic logging tools with small source-to-source (near-source excitation and reception) characteristics, these are all fiber optic acoustic sensing tools using fiber-optic composite cables. Conventional cable-based logging techniques are unsuitable for ultra-deep wells, horizontal wells, and highly deviated wells; existing instruments exhibit poor adaptability to these scenarios and cannot maintain stable, long-term operation.

[0005] Therefore, existing fiber optic sensing acoustic logging tools not only have certain limitations in application scenarios, but also, in ultra-deep wells, excessively long optical fiber composite cables are prone to fiber breakage due to their heavy weight. Summary of the Invention

[0006] The purpose of this invention is to provide at least one dual-logging-mode fiber optic sensing acoustic wave detection device and its control method. This invention avoids the defect of fiber optic composite cables in ultra-deep wells being pulled apart due to their heavy weight by incorporating an optical modulation / demodulation module, an optical coupling module, and a beam splitting module within the dual-logging-mode fiber optic sensing acoustic wave detection device operating downhole.

[0007] To address the aforementioned technical problems, at least one embodiment of this application provides a dual-logging-mode fiber optic sensing acoustic detection device, comprising:

[0008] Dual-logging mode fiber optic sensing acoustic wave detection device body;

[0009] The power supply module is located inside the dual-logging-mode fiber optic sensing acoustic wave detection device. It is used to provide power to the measurement control module, transmission line, transmission acoustic system and optical modulation and demodulation module located inside the dual-logging-mode fiber optic sensing acoustic wave detection device by directly powering the device through a battery stub or by converting externally supplied power through a power adapter stub.

[0010] The measurement and control module, connected to the optical modulation and demodulation module and the transmitting acoustic system, is used to issue pulse transmission commands to control the optical modulation and demodulation module to perform the operation of transmitting laser pulse signals, and to issue transmission commands to control the transmission line to provide transmission drive signals to the transmitting acoustic system;

[0011] The transmitting line is located inside the body of the dual-logging-mode fiber optic sensing acoustic wave detection device and connected to the measurement and control module. It is used to provide a transmitting drive signal to the transmitting acoustic system in response to the transmitting command sent by the measurement and control module.

[0012] The transmitting acoustic system is located inside the body of the dual-logging-mode fiber optic sensing acoustic wave detection device and is connected to the transmitting line. It is used to amplify the transmitting drive signal provided by the transmitting line and perform the excitation acoustic wave operation.

[0013] A sound insulation body is disposed between the transmitting sound system and the receiving sound system to block the direct wave excited by the transmitting sound system and propagating along the outer shell of the dual logging mode fiber optic sensing acoustic wave detection device.

[0014] The receiving acoustic system is located inside the body of the dual-logging mode fiber optic sensing acoustic wave detection device and is connected to the optical modulation and demodulation module via an optical fiber. The optical fiber is used to conduct the laser pulse signal. The receiving acoustic system is used to enhance the sensitivity of weak acoustic signals from the outside so that the optical fiber located inside the receiving acoustic system is disturbed, thereby coupling the mechanical vibration caused by the weak acoustic signal into the scattered light signal of the laser pulse signal.

[0015] The optical modulation and demodulation module is used to perform the operation of emitting a laser pulse signal into the optical fiber in response to the pulse emission command, and to demodulate the scattered light signal to obtain spectral data.

[0016] At least one embodiment of this application also provides a control method for the dual-logging-mode fiber optic sensing acoustic detection device as described above, the method comprising:

[0017] Determine the current well depth at which the dual-logging mode fiber optic sensing acoustic detection device is located in the well to be logged;

[0018] A transmission command is sent to control the transmission line to provide a transmission drive signal to the transmission acoustic system, so that the transmission acoustic system amplifies the transmission drive signal provided by the transmission line and performs an excitation sound wave operation, and acquires the scattered light signal coupled with the mechanical vibration caused by the sound wave collected by each sound wave receiving unit of the receiving acoustic system; wherein, the scattered light signal is the scattered light signal of the laser pulse transmitted through the optical fiber;

[0019] Based on the scattered light signals collected by each acoustic wave receiving unit, the strain generated by the fiber optic ring of each acoustic wave receiving unit at the current well depth is determined by a preset strain determination method.

[0020] Based on the strain generated by the fiber optic ring of each acoustic receiving unit, waveform curves corresponding to each acoustic receiving unit are generated by plotting. Based on all the waveform curves, the wave impedance imaging results of the formation around the well to be measured at the current well depth are determined by a preset processing method.

[0021] The dual-logging-mode fiber optic sensing acoustic wave detection device and its control method provided in this application, compared with the prior art, place the optical modulation and demodulation module in the dual-logging-mode fiber optic sensing acoustic wave detection device working downhole. Since the optical modulation and demodulation module is close to the measurement end of the dual-logging-mode fiber optic sensing acoustic wave detection device, the optical signal attenuation is small. This dual-logging-mode fiber optic sensing acoustic wave detection device can also be transported downhole using drilling tools, and can adapt to wells with harsh well conditions such as highly deviated wells and horizontal wells. This application can avoid the defect of fiber optic composite cables in ultra-deep wells being pulled apart due to their own weight.

[0022] In addition, a voltage boosting unit and a transmitting transducer are provided in the transmitting acoustic system of the dual-logging mode fiber optic sensing acoustic wave detection device; wherein:

[0023] The boost unit is used to amplify the transmission drive signal provided by the transmission line, thereby driving the transmission transducer to vibrate;

[0024] The transmitting transducer is used to convert electrical energy into mechanical energy according to the amplified transmitting drive signal, and then excite sound waves through vibration; wherein, the transmitting transducer includes:

[0025] One or more of the following: monopole emitter transducer, dipole emitter transducer, and quadrupole emitter transducer.

[0026] In addition, the receiving acoustic system of the dual-logging-mode fiber optic sensing acoustic wave detection device includes multiple acoustic wave receiving units. Each acoustic wave receiving unit is equipped with an optical fiber ring support. The optical fiber is wound layer by layer on the optical fiber ring support along the axis of the dual-logging-mode fiber optic sensing acoustic wave detection device body according to a preset winding strategy to form an optical fiber ring.

[0027] Furthermore, the fiber optic ring support in the receiving acoustic system of the dual-logging-mode fiber optic sensing acoustic wave detection device is cylindrical, and the preset winding strategy includes a uniform winding strategy, which includes:

[0028] At any position along the axis of the dual-logging mode fiber optic sensing acoustic wave detection device, the number of turns of the fiber optic ring is the same at any location on the fiber optic ring support.

[0029] Furthermore, the fiber optic ring support in the receiving acoustic system of the dual-logging-mode fiber optic sensing acoustic detection device is cylindrical, and the preset winding strategy includes a non-uniform winding strategy, which includes:

[0030] With the optical fiber ring support at the midpoint of the axis of the dual-logging mode optical fiber sensing acoustic wave detection device as the center, the number of turns of the optical fiber ring decreases sequentially along the axis of the dual-logging mode optical fiber sensing acoustic wave detection device.

[0031] In addition, the optical modulation and demodulation module of the dual-logging mode fiber optic sensing acoustic wave detection device includes:

[0032] The storage submodule is used to store the spectral data obtained by the optical modulation and demodulation module.

[0033] In addition, the scattered light signal is a backscattered Rayleigh light signal.

[0034] In addition, the optical fiber installed in the dual-logging-mode fiber optic sensing acoustic detection device is a single-mode optical fiber.

[0035] In addition, the method further includes connecting the dual-logging-mode fiber optic sensing acoustic detection device via armored cable or drill pipe:

[0036] By controlling the lifting or lowering of the armored cable or drill pipe, the position of the dual-logging-mode fiber optic sensing acoustic detection device in the well to be logged can be controlled. Attached Figure Description

[0037] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0038] Figure 1 This is a schematic diagram of the structure of a dual-logging-mode fiber optic sensing acoustic wave detection device provided in an embodiment of the present disclosure;

[0039] Figure 2This is a schematic diagram of a dual-logging mode fiber optic sensing acoustic wave detection device that supports delivery to the well via drill pipe, as provided in Embodiment 3 of this disclosure.

[0040] Figure 3 A schematic diagram of another fiber optic sensing acoustic detection device for dual logging modes, provided in Embodiment 3 of this disclosure, which supports delivery to the well via drill pipe.

[0041] Figure 4 This is a schematic diagram of the structure of a dual-logging mode fiber optic sensing acoustic wave detection device that supports transmission to the well via armored cable, as provided in Embodiment 4 of this disclosure.

[0042] Figure 5 A schematic diagram of another dual-logging mode fiber optic sensing acoustic wave detection device that supports transmission to the well via armored cable, provided in Embodiment 4 of this disclosure;

[0043] Figure 6 A flowchart illustrating a control method for a dual-logging-mode fiber optic sensing acoustic detection device provided in this disclosure embodiment;

[0044] Figure 7 A flowchart illustrating another control method for a dual-logging-mode fiber optic sensing acoustic detection device provided in this disclosure.

[0045] Figure label:

[0046] 1-Plug, 21-Battery sub-section, 3-Transmitter line sub-section, 4-Transmitter acoustic system sub-section, 41-Four-pole transmitter transducer, 42-Dipole transmitter transducer, 43-Monopolar transmitter transducer, 5-Sound insulation body, 6-Receiver acoustic system sub-section, 61-Metal outer casing, 62-Fiber optic ring support, 63-Sound insulation connection support, 64-Bullet, 7-Optical modulation and demodulation sub-section, 8-Measurement and control sub-section, 9-Well inclination and azimuth logging tool sub-section, 91-Azimuth sensor, 92-Well inclination sensor, 10-Guidance and centering sub-section, 11-Drill pipe; 22-Power adapter sub-section, 100-Horse head, 110-Cable / optical fiber composite cable. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand the present invention. However, the technical solutions claimed in the present invention can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0048] To facilitate understanding of the embodiments of this application, the relevant content of the dual-logging mode fiber optic sensing acoustic detection device will be introduced first.

[0049] Example 1

[0050] The embodiments of the present invention relate to a dual-logging-mode fiber optic sensing acoustic wave detection device.

[0051] Compared with the prior art, the embodiments of the present invention place the optical modulation and demodulation module in the dual logging mode fiber optic sensing acoustic wave detection device operating downhole. Since the optical modulation and demodulation module is close to the measurement end of the dual logging mode fiber optic sensing acoustic wave detection device, the optical signal attenuation is small. It can also be transported downhole by drilling tools, which can adapt to wells with harsh well conditions such as highly deviated wells and horizontal wells. It can avoid the defect of optical fiber breakage caused by the weight of the optical fiber composite cable in ultra-deep wells.

[0052] The following is a detailed description of the implementation details of the dual-logging mode fiber optic sensing acoustic wave detection device in this embodiment. The following content is only for the convenience of understanding and is not necessary for implementing this solution.

[0053] Figure 1 This is a schematic diagram of the structure of a dual-logging-mode fiber optic sensing acoustic detection device provided in an embodiment of this disclosure, as shown below. Figure 1 As shown, the dual-logging-mode fiber optic sensing acoustic detection device provided in this embodiment includes:

[0054] Dual-logging mode fiber optic sensing acoustic wave detection device body;

[0055] The power supply module is located inside the dual-logging-mode fiber optic sensing acoustic wave detection device. It is used to provide power to the measurement control module, transmission line, transmission acoustic system and optical modulation and demodulation module located inside the dual-logging-mode fiber optic sensing acoustic wave detection device by directly powering the device through the battery short section or by converting the power supplied from the outside through the power adapter short section.

[0056] The measurement and control module, connected to the optical modulation and demodulation module and the transmitting acoustic system, is used to issue pulse transmission commands to control the optical modulation and demodulation module to perform the operation of transmitting laser pulse signals, and to issue transmission commands to control the transmission line to provide transmission drive signals to the transmitting acoustic system;

[0057] The transmitting line is located inside the body of the dual-logging-mode fiber optic sensing acoustic wave detection device and connected to the measurement and control module. It is used to provide a transmitting drive signal to the transmitting acoustic system in response to the transmitting command sent by the measurement and control module.

[0058] The transmitting acoustic system is located inside the body of the dual-logging-mode fiber optic sensing acoustic wave detection device and is connected to the transmitting line. It is used to amplify the transmitting drive signal provided by the transmitting line and perform the excitation acoustic wave operation.

[0059] A sound insulation body is disposed between the transmitting sound system and the receiving sound system to block the direct wave excited by the transmitting sound system and propagating along the outer shell of the dual logging mode fiber optic sensing acoustic wave detection device.

[0060] The receiving acoustic system is set inside the body of the dual-logging mode fiber optic sensing acoustic wave detection device and connected to the optical modulation and demodulation module via optical fiber. The optical fiber is used to conduct the laser pulse signal. The receiving acoustic system is used to enhance the sensitivity of weak acoustic signals from the outside so that the optical fiber located inside the receiving acoustic system is disturbed, thereby coupling the mechanical vibration caused by the weak acoustic signal into the scattered light signal of the laser pulse signal.

[0061] The optical modulation and demodulation module is used to respond to pulse emission commands by emitting laser pulse signals into the optical fiber and demodulating the scattered light signals to obtain spectral data.

[0062] In some embodiments, the scattered light signal is a backscattered Rayleigh light signal.

[0063] Specifically, the measurement and control module, power supply module, transmitting line, transmitting acoustic system, sound insulation body, receiving acoustic system, and optical modulation and demodulation module are all housed inside the dual-logging-mode fiber optic sensing acoustic wave detection device. The specific connection methods between the modules in this dual-logging-mode fiber optic sensing acoustic wave detection device can be communication connections, electrical connections, or hard connections, etc., and can also include both communication and hard connections, or electrical and hard connections simultaneously, depending on actual needs. Among these:

[0064] The power supply module may include a battery short section or a power adapter short section, which can be used to provide the required power to the measurement control module, the transmitting line, the transmitting acoustic system and the optical modulation and demodulation module by directly powering the battery short section or converting the externally supplied power through the power adapter short section; in addition, the power supply module can also power other modules set in the dual logging mode fiber optic sensing acoustic wave detection device.

[0065] The transmitting line provides a transmission drive signal to the transmitting acoustic system according to the transmission command sent by the measurement and control module, so as to drive the transmitting acoustic system to excite the sound wave signal;

[0066] The transmitting acoustic system is used to amplify the transmitting drive signal provided by the transmitting line and perform the operation of exciting acoustic waves (for example, to excite the acoustic transducer to vibrate, thereby exciting the acoustic wave signal).

[0067] Sound insulation is used to block direct waves excited by the transmitting sound system and propagating along the outer shell of the dual-logging mode fiber optic sensing acoustic wave detection device.

[0068] The receiving acoustic system is connected to the optical modulation and demodulation module via optical fiber. The optical fiber is used to conduct laser pulse signals. The receiving acoustic system is used to sensitize weak acoustic signals from the outside (e.g., wellbore and / or formation) to cause disturbance in the optical fiber located inside the receiving acoustic system, thereby coupling the mechanical vibration caused by the weak acoustic signal into the scattered light signal of the laser pulse signal.

[0069] The optical modulation and demodulation module is used to execute the operation of emitting laser pulse signals into the optical fiber in response to the pulse emission command, and to demodulate the scattered light signals to obtain spectral data.

[0070] Optionally, the optical fiber connecting the receiving acoustic system and the optical modulation and demodulation module is a single-mode optical fiber, which has advantages such as resistance to electromagnetic interference, high temperature resistance, large bandwidth, and long transmission distance.

[0071] In some embodiments, the dual-logging-mode fiber optic sensing acoustic detection device may further include:

[0072] Azimuth sensor, well inclination sensor and centering device.

[0073] As a specific application example, this dual-logging-mode fiber optic sensing acoustic detection device may include:

[0074] The system includes a transmitting acoustic system section, a sound insulation body between the transmitting and receiving acoustic system sections, a receiving acoustic system section, an optical modulation and demodulation section containing an optical modulation and demodulation module, a measurement and control section containing a measurement and control module, a well inclination and azimuth logging tool section containing an azimuth sensor and a well inclination sensor, a battery section containing a power supply module, and a guide and centralizing section containing a centralizing device; all sections can be connected by a movable connection.

[0075] Understandably, this dual-logging-mode fiber optic sensing acoustic detection device includes an optical modulation and demodulation section containing an optical modulation and demodulation module. Since the optical modulation and demodulation module is placed within the dual-logging-mode fiber optic sensing acoustic detection device, which is located downhole in practical applications, this avoids fiber breakage due to the weight of the optical-electric composite cable in ultra-deep wells. This dual-logging-mode fiber optic sensing acoustic detection device also supports both armored cable delivery and drill pipe delivery modes, thus exhibiting good adaptability to complex wells such as ultra-deep wells, horizontal wells, and highly deviated wells.

[0076] It should be noted that this dual-logging-mode fiber optic acoustic wave detection device can be connected via either an armored cable or drill pipe. The device can be transmitted to a predetermined layer downhole by controlling the lifting or lowering of the armored cable or drill pipe. For example, the device can be first connected via an armored cable or drill pipe, and then its position within the well can be controlled by lifting or lowering the cable or drill pipe. The armored cable can be a power cable or a fiber optic composite cable.

[0077] Example 2

[0078] Based on the above embodiments, the embodiments of the present invention are a detailed description of the above dual-logging mode fiber optic sensing acoustic wave detection device.

[0079] In some possible scenarios, the scattered light signal collected by the dual-logging mode fiber optic sensing acoustic wave detection device includes a first scattered light signal without acoustic wave disturbance and a second scattered light signal coupled with mechanical vibration caused by acoustic waves; wherein, both the first and second scattered light signals are backscattered Rayleigh light signals.

[0080] In some embodiments, the optical modulation and demodulation module includes a storage submodule for storing the spectral data obtained by the optical modulation and demodulation module.

[0081] Specifically, the optical modulation and demodulation module may include: a pulsed laser modulation submodule, a demodulation submodule, an optical coupling and splitting submodule, and a storage submodule. Furthermore, when the optical modulation and demodulation module is housed within an optical modulation and demodulation section, all these submodules are housed within the pressure-bearing housing of the optical modulation and demodulation section.

[0082] The pulsed laser modulation submodule is used to generate laser pulse signals with a specific pulse width and propagate them along the optical fiber;

[0083] The demodulation submodule is used to receive backscattered Rayleigh light signals and process the received backscattered Rayleigh light signals into corresponding spectral data;

[0084] The optical coupling and splitting module is used to guide the laser pulses generated by the modulation module into the sensing fiber and to guide the backscattered Rayleigh light in the sensing fiber into the demodulation module.

[0085] The storage submodule is used to store the spectral data obtained by the demodulation submodule, which can be read after the logging is completed and the instrument is removed from the well, or transmitted to the surface via a fiber optic composite cable.

[0086] In some possible scenarios, a communication module can also be set up in the dual-logging mode fiber optic sensing acoustic wave detection device. With the help of this communication module, spectral data stored in the storage submodule can be acquired through wired or wireless means, and then the acoustic wave waveform curve of the current location can be generated based on the spectral data collected by the dual-logging mode fiber optic sensing acoustic wave detection device.

[0087] In some embodiments, a booster unit and a transmitting transducer are provided in the transmitting acoustic system of the above-described dual-logging-mode fiber optic sensing acoustic wave detection device; wherein:

[0088] The boost unit is used to amplify the transmission drive signal provided by the transmission line, thereby driving the transmission transducer to vibrate;

[0089] The transmitting transducer is used to convert electrical energy into mechanical energy according to the amplified transmitting drive signal, and then excite sound waves through vibration; wherein, the transmitting transducer includes:

[0090] One or more of the following: monopole emitter transducer, dipole emitter transducer, and quadrupole emitter transducer.

[0091] It is understood that the transmitting transducer may include any one or a combination of monopole transmitting transducers, dipole transmitting transducers and quadrupole transmitting transducers.

[0092] Optionally, the transmitting line drives the transmitting transducer to generate monopole, dipole, or quadrupole vibrations according to the specific timing sequence provided by the instructions issued by the measurement and control module.

[0093] The DC power supplied by the power supply module or power adapter sub-section is boosted and stored in the energy storage capacitor. The transmitting line excites the transmitting transducer by controlling the switching of the MOSFET according to a specific timing sequence.

[0094] In some embodiments, the measurement control module can also be used to control the power supply module to turn on and off according to a preset power supply strategy. The preset power supply strategy can be set according to actual needs.

[0095] In some embodiments, the measurement control module can also be used to control the time synchronization between the transmitting acoustic system and the optical modulation and demodulation module.

[0096] Specifically, the transmission and acquisition timing can be provided by the measurement control module (e.g., the measurement control module located in the measurement control section). The measurement control module controls the time synchronization between the transmitting acoustic system and the optical modulation and demodulation module, provides a specific timing for transmission and reception, and controls the power supply module to turn on at regular intervals to provide power to the modules that need power in this dual-logging mode fiber optic sensing acoustic wave detection device.

[0097] In some embodiments, the acoustic receiving system includes multiple acoustic receiving units, and each acoustic receiving unit is provided with an optical fiber ring support. The optical fiber is wound layer by layer on the optical fiber ring support along the axis of the dual-logging mode optical fiber sensing acoustic wave detection device according to a preset winding strategy to form an optical fiber ring.

[0098] Optionally, the receiving acoustic system can be continuously turned on while the dual-logging mode fiber optic sensing acoustic wave detection device is working, or it can be turned on within a certain time range after the sound source is excited.

[0099] In this receiver system, each receiving unit uses an optical fiber wound in a ring along the axial direction, layer by layer. The optical fiber wound on the fiber ring support in each receiving unit can be wound uniformly or non-uniformly. In the following text, the fiber ring support with the wound optical fiber will be referred to as the fiber ring.

[0100] In some embodiments, the preset winding strategy includes a uniform winding strategy, which includes:

[0101] At any position along the axis of the dual-logging mode fiber optic sensing acoustic wave detection device, the number of turns of the fiber optic ring is the same.

[0102] In some embodiments, the preset winding strategy includes a non-uniform winding strategy, which includes:

[0103] With the center of the fiber optic ring support on the axis of the dual-logging mode fiber optic sensing acoustic wave detection device, the number of turns of the fiber optic ring decreases sequentially along the axis of the dual-logging mode fiber optic sensing acoustic wave detection device.

[0104] For example, in uniform winding, the number of turns in the fiber optic ring is n at all points; in non-uniform winding, the number of turns at both ends is m, and the number of turns in the center is n, with sparse turns at both ends and dense turns in the center, i.e., m>n. In uniform winding, the fiber optic ring is encapsulated in a thin-walled stainless steel casing to increase the lateral force-bearing area and deformation. The fiber optic ring support can be made of a rigid material with good elasticity, low Young's modulus, and high temperature resistance, such as polytetrafluoroethylene, polyetheretherketone, or polyvinyl chloride. The fiber optic ring length is 10cm–15cm, and the diameter is 40mm–100mm. The fiber optic rings can be arranged at specific intervals, either equal or increasing in distance from the transmitter.

[0105] With each module housed in its corresponding section, except for the transmitting and receiving sound systems and the sound insulation, the exterior of the remaining sections is a pressure-bearing outer shell made of metal material (e.g., titanium steel or 17-4 stainless steel), and the internal circuit boards are mounted on a detachable circuit frame.

[0106] It should be noted that the positions of the transmitting and receiving acoustic systems in this dual-logging-mode fiber optic sensing acoustic wave detection device are interchangeable. This dual-logging-mode fiber optic sensing acoustic wave detection device can use drill pipe, coiled tubing, cable, or fiber optic composite cable for transmission. When using drill pipe or coiled tubing for transmission, the dual-logging-mode fiber optic sensing acoustic wave detection device is powered by a power supply module located inside it.

[0107] The dual-logging-mode fiber optic sensing acoustic wave detection device provided in this embodiment has the advantage of low optical signal attenuation because the optical modulation and demodulation module, the transmitting acoustic system, and the receiving acoustic system are all located inside the device and downhole. This dual-logging-mode fiber optic sensing acoustic wave detection device can also be transported downhole using drilling tools, thus adapting to harsh well conditions such as highly deviated and horizontal wells. The special winding method of the optical fiber in this dual-logging-mode fiber optic sensing acoustic wave detection device is for sensitivity enhancement. Furthermore, short sections for adjusting the fiber length can be added to this dual-logging-mode fiber optic sensing acoustic wave detection device according to actual needs.

[0108] Example 3

[0109] Based on the above embodiments, this embodiment provides a specific example.

[0110] In this embodiment, the application of the dual-logging-mode fiber optic sensing acoustic detection device in well logging is used as an example for illustration.

[0111] Please refer to the following. Figure 2 , Figure 2 This is a schematic diagram of a dual-logging mode fiber optic sensing acoustic wave detection device that supports delivery to the well via drill pipe, as provided in Embodiment 3 of this disclosure.

[0112] Specifically, the dual-logging-mode fiber optic sensing acoustic detection device disclosed in this embodiment includes the following modules:

[0113] Plug 1, Battery sub 21, Transmitter line sub 3, Transmitter acoustic system sub 4, Quadrupole transducer 41, Dipole transducer 42, Monopole transducer 43, Sound insulation body 5, Receiver acoustic system sub 6, Metal outer casing 61, Fiber optic ring support 62, Sound insulation connection support 63, Rubber 64, Optical modulation and demodulation sub 7, Measurement and control sub 8, Well inclination and azimuth logging tool sub 9, Azimuth sensor 91, Well inclination sensor 92, Guide and centering sub 10, Drill pipe 11.

[0114] The plug 1 is approximately conical in shape with a hemispherical top; it serves two purposes: firstly, to ensure the bottom is sealed and prevent mud from entering the instrument; and secondly, to act as a guide.

[0115] The battery section 21, located at the bottom of the dual-logging mode fiber optic sensing acoustic detection device and connected to the plug 1, can be used to power the transmitting line section 3.

[0116] After the energy provided by the battery section 21 is boosted, the transmitting line section 3, under the control of the measurement and control section 8, excites one or more of the quadrupole transmitting transducers 41, dipole transmitting transducers 42, and monopole transmitting transducers 43 in the transmitting acoustic system section 4 in a specific order according to the transmission timing command sent by the measurement and control section 8.

[0117] The sound insulation body 5 is used to block the acoustic wave signal generated by the excitation of the transmitting acoustic system stub 4 from propagating in the form of a direct wave along the outer shell of the dual logging mode fiber optic sensing acoustic wave detection device.

[0118] The receiving acoustic section 6 internally includes one or more fiber optic ring supports 62 with a diameter of r1. The fiber optic ring supports 62 are used for winding optical fibers. The fiber optic ring supports 62 are hollow thin-walled cylinders with annular thin-walled plates at the top and bottom ends. The center of the ring is hollowed out with a radius of r2. <r1)。

[0119] Optionally, a bladder may be fitted on the outer surface of the fiber optic ring support 62, and silicone oil may be filled into the sealed space inside to balance the wellbore pressure; in addition, a steel cylinder with one or more sound-permeable windows may be arranged circumferentially on the outside of the bladder for protection.

[0120] The outer diameter of the end face of the fiber optic ring support 62 is r3 (r3>r1), and the end faces of adjacent fiber optic ring supports 62 are connected by sound-insulating connectors. The optical fiber is wound around the outside of the fiber optic ring support 62 in a specific manner, forming a fiber optic ring by winding it layer by layer in a ring. The winding method can be any of the following: each acoustic receiving unit uses an optical fiber wound layer by layer along the axial direction in a ring, which can be uniform or non-uniform winding. In uniform winding, the number of turns in the fiber optic ring is n at all points; in non-uniform winding, the number of turns at both ends is m, sparse at both ends, and n in the center, with m>n in the middle. In uniform winding, the fiber optic ring is encapsulated in a thin-walled stainless steel metal shell to increase the lateral force-bearing area and deformation. The fiber optic ring support 62 is made of a rigid material with good elasticity, low Young's modulus, and high temperature resistance, such as polytetrafluoroethylene, polyetheretherketone, or polyvinyl chloride. The diameter of the fiber optic ring can be 40mm to 100mm, and the length can be 10cm to 15cm. The fiber optic rings can be arranged at specific intervals, which can be equal or increased from near to far from the transmitter. The outer diameter of the bladder 64 is r3, and the receiving acoustic system section 6 is surrounded by a metal outer sheath 61 with a radius of r4 (r4>r3).

[0121] The optical modulation and demodulation section 7 is used to emit laser pulses and receive backscattered Rayleigh scattering. Based on the phase change of the received scattered light, the acoustic wave amplitude at each fiber ring is analyzed.

[0122] The azimuth sensor 91 in the wellbore azimuth logging tool sub-section 9 can accurately measure the azimuth of the X-ray transducer in the horizontal plane, while the wellbore inclination sensor 92 is used to provide the three-dimensional spatial attitude of the entire device.

[0123] The guide centering sub 10 is used to center the instrument and scrape the well wall.

[0124] Drill pipe 11 is used to transport a dual-logging-mode fiber optic sensing acoustic detection device.

[0125] It should be noted that the positions of the transmitting line section 3 and the optical modulation / demodulation section 7 are interchangeable in the dual-logging mode fiber optic sensing acoustic wave detection device; the positions of the transmitting acoustic section 4 and the receiving acoustic section 6 are also interchangeable in the dual-logging mode fiber optic sensing acoustic wave detection device. For details, please refer to... Figure 3 .

[0126] Example 4

[0127] Based on the above embodiments, this embodiment provides another specific example.

[0128] In this embodiment, the application of the dual-logging-mode fiber optic sensing acoustic detection device (hereinafter referred to as the instrument) in logging is described as an example.

[0129] Please refer to the following. Figure 4 , Figure 4 This is a schematic diagram of a dual-logging mode fiber optic sensing acoustic wave detection device that supports downhole transmission via armored cable, as provided in Embodiment 4 of this disclosure.

[0130] Specifically, the dual-logging-mode fiber optic sensing acoustic detection device disclosed in this embodiment includes the following modules:

[0131] Plug 1, Power adapter subsection 22, Transmitter line subsection 3, Transmitter acoustic system subsection 4, Quadrupole transducer 41, Dipole transducer 42, Monopole transducer 43, Sound insulation body 5, Receiver acoustic system subsection 6, Metal outer casing 61, Fiber optic ring support 62, Sound insulation connection support 63, Sheath 64, Optical modulation and demodulation subsection 7, Measurement and control subsection 8, Well inclination and azimuth logging tool subsection 9, Azimuth sensor 91, Well inclination sensor 92, Horse head 100, Cable / optical fiber composite cable 110.

[0132] The plug 1 is approximately conical in shape with a hemispherical top. It serves two purposes: firstly, to ensure a tight seal at the bottom and prevent mud from entering the instrument; and secondly, to act as a guide.

[0133] The power adapter section 22 is used to convert the electrical energy provided by the cable / optical composite cable 11 into the electrical energy required by each module in the dual-logging mode fiber optic sensing acoustic wave detection device.

[0134] The power adapter section 22, located at the bottom of the dual logging mode fiber optic sensing acoustic detection device and connected to the plug 1, is used to supply power to the transmitting line section 3.

[0135] Under the control of the measurement and control section 8, the transmitting line section 3 uses the energy provided by the power adapter section 22 to boost the voltage according to the transmission timing command sent by the measurement and control section 8, and then excites one or more of the quadrupole transmitting transducers 41, dipole transmitting transducers 42, and monopole transmitting transducers 43 in the transmitting acoustic system section 4 in a specific sequence.

[0136] The sound insulation element 5 is used to block the sound wave signal generated by the excitation of the transmitting sound system short section 4 from propagating along the outer shell of the instrument in the form of a direct wave.

[0137] The receiving acoustic section 6 internally includes one or more fiber optic ring supports with a diameter of r1. These fiber optic ring supports are used for winding the fiber optic cable. The fiber optic ring supports are hollow, thin-walled cylinders with annular thin-walled plates at the top and bottom. The center of the ring is hollowed out, with a radius of r2. <r1)。

[0138] The outer diameter of the end face of the fiber optic ring support 62 is r3 (r3>r1), and the end faces of adjacent fiber optic ring supports 62 are connected by sound-insulating connectors. The optical fiber is wound around the outside of the fiber optic ring support 62 in a specific manner, forming a fiber optic ring by winding it layer by layer in a ring. The winding method can be any of the following: each acoustic receiving unit uses an optical fiber wound layer by layer along the axial direction in a ring, which can be uniform or non-uniform winding. In uniform winding, the number of turns in the fiber optic ring is n at all points; in non-uniform winding, the number of turns at both ends is m, sparse at both ends, and n in the center, with m>n in the middle. In uniform winding, the fiber optic ring is encapsulated in a thin-walled stainless steel metal shell to increase the lateral force-bearing area and deformation. The fiber optic ring support 62 is made of a rigid material with good elasticity, low Young's modulus, and high temperature resistance, such as polytetrafluoroethylene, polyetheretherketone, or polyvinyl chloride. The diameter of the fiber optic ring can be 40mm to 100mm, and the length can be 10cm to 15cm. The fiber optic rings can be arranged at specific intervals, which can be equal or increased from near to far from the transmitter. The outer diameter of the bladder 64 is r3, and the receiving acoustic system section 6 is surrounded by a metal outer sheath 61 with a radius of r4 (r4>r3).

[0139] The optical modulation and demodulation section 7 is used to emit laser pulses and receive backscattered Rayleigh scattering. Based on the phase change of the received scattered light, the acoustic wave amplitude at each fiber ring is analyzed.

[0140] The azimuth sensor 91 in the wellbore azimuth logging tool sub-section 9 can accurately measure the azimuth of the transmitting transducer in the horizontal plane, while the wellbore inclination sensor 92 is used to provide the three-dimensional spatial attitude of the entire device.

[0141] The 100-type headband is used to establish a mechanical connection between the cable / optical composite cable 110 and the dual-logging mode fiber optic sensing acoustic detection device to straighten the instrument.

[0142] It should be noted that the positions of transmitting line section 3 and transmitting acoustic system section 4, receiving acoustic system section 6 and optical modulation / demodulation section 7 are interchangeable in the dual-logging mode fiber optic sensing acoustic wave detection device. See the following for details. Figure 5 .

[0143] Example 5

[0144] Based on the above embodiments, this embodiment provides a control method for the dual-logging-mode fiber optic sensing acoustic detection device as described above.

[0145] Please refer to Figure 6 , Figure 6 A flowchart illustrating a control method for a dual-logging-mode fiber optic sensing acoustic detection device provided in this embodiment. The control method provided in this embodiment includes the following steps:

[0146] Step 610: Determine the current well depth of the location of the dual-logging mode fiber optic sensing acoustic detection device in the well to be logged.

[0147] Optionally, the top of the dual-logging-mode fiber optic sensing acoustic detection device is connected by the drill pipe end-to-end or by an armored cable, and the dual-logging-mode fiber optic sensing acoustic detection device is delivered downhole, and the length of the drill pipe / armored cable is recorded at the wellhead.

[0148] As an example, the movable end of the optoelectronic composite cable is mechanically and electrically connected to the downhole equipment using a screwdriver. The fixed end of the optoelectronic composite cable is connected to the surface system and the optical modulation / demodulation module via slip rings. The cable core of the optoelectronic composite cable is connected to the surface system, and the optical fiber is connected to the optical modulation / demodulation module. The optoelectronic composite cable is lowered using a winch system, and the dual-logging mode fiber optic sensing acoustic wave detection device is placed at a specific location in the well to begin detection. During the measurement process, the dual-logging mode fiber optic sensing acoustic wave detection device can be raised, lowered, or suspended. Based on the lowered length of the optoelectronic composite cable, the current well depth of the dual-logging mode fiber optic sensing acoustic wave detection device in the well to be logged can be determined.

[0149] Step 620: Emit a laser pulse to acquire the first scattered light signal collected by each acoustic receiving unit in the receiving acoustic system of the dual-logging mode fiber optic sensing acoustic wave detection device.

[0150] Specifically, the pulsed laser signal emitted by the pulsed laser modulation submodule enters the optical fiber connected to the fiber ring through the coupler. The beam splitter separates the backscattered Rayleigh light and sends it to the demodulation submodule, and stores the scattered light spectrum information of the demodulation submodule in the storage submodule.

[0151] Specifically, the acquisition of scattered light signals can include two stages: a first stage and a second stage.

[0152] In the first stage: laser pulses are emitted through the pulsed laser modulation submodule and the first scattered light signal collected by each acoustic wave receiving unit is demodulated and recorded. At this time, the transmission line is not working.

[0153] Step 630: Send a transmission command to control the transmission line to provide a transmission drive signal to the transmitting acoustic system, so that the transmitting acoustic system amplifies the transmission drive signal provided by the transmission line and performs the excitation of acoustic waves, and acquires the second scattered light signal coupled with the mechanical vibration caused by the acoustic waves collected by each acoustic wave receiving unit of the receiving acoustic system.

[0154] Specifically, the transmitting line responds to the transmitting acoustic system by providing a transmission drive signal. The transmitting acoustic system amplifies the transmission drive signal provided by the transmitting line and then performs an excitation operation based on the amplified transmission drive signal, thereby generating sound waves. After the sound waves are generated, the receiving acoustic system collects the second scattered light signal coupled with the mechanical vibrations caused by the sound waves through each sound wave receiving unit.

[0155] Specifically, the acoustic system signals can be transmitted in a specific timing sequence by synchronizing the transmission and reception times of the acoustic system sub-sub ...

[0156] In the second stage: a transmission command is sent through a dual-logging mode fiber optic sensing acoustic detection device, which in turn drives the transmitting acoustic system to excite monopole, dipole, or quadrupole vibrations. The vibrations are transmitted to the formation through the wellbore fluid, emitted through geological anomalies, and return to the wellbore. The reflected waves act on each acoustic receiving unit, and the second scattered light signal collected by each acoustic receiving unit under the disturbance of the reflected waves is demodulated and recorded.

[0157] Step 640: Based on the first and second scattered light signals collected by each acoustic wave receiving unit, determine the strain generated by the fiber optic ring of each acoustic wave receiving unit at the current well depth using a preset strain determination method.

[0158] Optionally, the method for determining the predefined strain may include time-domain localization and frequency-domain analysis methods.

[0159] Furthermore, time-domain positioning and frequency-domain analysis methods can be used to obtain the strain of the optical fiber at one or more depth locations.

[0160] Step 650: Based on the strain generated by the fiber optic ring of each acoustic receiving unit, generate the waveform curve corresponding to each acoustic receiving unit by plotting, and determine the wave impedance imaging result of the formation around the well at the current well depth based on all the waveform curves through a preset processing method.

[0161] Among them, the waveform curve is the curve of amplitude changing with time, and the origin of the coordinate system can be regarded as the excitation start time.

[0162] Optionally, steps 610 to 650 are repeated when the dual-logging mode fiber optic sensing acoustic detection device is located at different depths inside the wellbore, thereby obtaining acoustic logging data corresponding to multiple depths.

[0163] Optionally, the acoustic wave amplitude signals collected by each channel of the acoustic receiving system at different depths are processed by deconvolution, amplitude compensation, frequency domain filtering, wave field separation, and offset imaging to obtain wave impedance imaging results in all directions around the well.

[0164] In some embodiments, the dual-logging-mode fiber optic sensing acoustic detection device is connected via an armored cable or drill pipe, and the method further includes:

[0165] By controlling the lifting or lowering of the armored cable or drill pipe, the position of the dual-logging-mode fiber optic sensing acoustic detection device in the well to be logged can be controlled.

[0166] Specifically, by lifting or lowering the optical fiber composite cable, the position of the dual-logging mode fiber optic sensing acoustic wave detection device in the well to be logged can be changed. After reaching the predetermined position, the dual-logging mode fiber optic sensing acoustic wave detection device can be suspended at the current position.

[0167] As an example, the practical application of the control method based on the above-mentioned dual-logging mode fiber optic sensing acoustic detection device may include the following steps:

[0168] S1: Connect the dual-logging-mode fiber optic sensing acoustic wave detection devices in sequence at the wellhead, configure the measurement control sub, and enable the dual-logging-mode fiber optic sensing acoustic wave detection devices to start working after a specific time or at a specific depth.

[0169] S2: The dual-logging mode fiber optic sensing acoustic wave detection device is transported by connecting drill pipes one by one or by armored cables at the top, and the length of the drill pipes or armored cables entering the well is recorded at the wellhead.

[0170] S3: The lower end of the dual-logging mode fiber optic sensing acoustic wave detection device is lowered to the top of the well section to be measured. At this time, the dual-logging mode fiber optic sensing acoustic wave detection device starts to be powered on and works.

[0171] S4: Measure the timing of the synchronous transmission and reception of the acoustic system short sections, and transmit acoustic signals according to a specific timing sequence. The pulsed laser signal emitted by the pulsed laser modulation submodule enters the optical fiber connected to the fiber ring through the coupler. The beam splitter separates the backscattered Rayleigh light and sends it to the demodulation submodule, and stores the spectral information of the scattered light in the demodulation submodule in the storage submodule.

[0172] S5: After the dual-logging mode fiber optic sensing acoustic wave detection device is delivered to the bottom of the well section to be measured, the drill pipe is pulled out one by one from the wellhead, and the length of the drill pipe above the dual-logging mode fiber optic sensing acoustic wave detection device is recorded.

[0173] S6: The dual-logging mode fiber optic sensing acoustic wave detection device is brought out of the wellhead and the measurement is stopped; the spectral data is read from the storage sub-module of the dual-logging mode fiber optic sensing acoustic wave detection device and fed back to the host computer or ground control system.

[0174] S7: By analyzing the data stored in the storage submodule, the phase change of the scattered light can be obtained, and the fiber strain at different fiber ring positions can be obtained, which can reflect the amplitude of the sound wave.

[0175] S8: The acoustic wave amplitude signals collected by each channel of the acoustic system at different depths are processed by deconvolution, amplitude compensation, frequency domain filtering, wave field separation, and offset imaging to obtain wave impedance imaging results in all directions around the well.

[0176] Example 6

[0177] Based on the above embodiments, this embodiment provides a control method for the dual-logging-mode fiber optic sensing acoustic detection device as described above.

[0178] Please refer to Figure 7 , Figure 7 A flowchart illustrating another control method for a dual-logging-mode fiber optic sensing acoustic detection device provided in this embodiment. The control method provided in this embodiment includes the following steps:

[0179] Step 710: Determine the current well depth of the location of the dual-logging mode fiber optic sensing acoustic detection device in the well to be logged.

[0180] Optionally, the top of the dual-logging-mode fiber optic sensing acoustic detection device is connected by the drill pipe end-to-end or by an armored cable, and the dual-logging-mode fiber optic sensing acoustic detection device is delivered downhole, and the length of the drill pipe / armored cable is recorded at the wellhead.

[0181] As an example, the movable end of the optoelectronic composite cable is mechanically and electrically connected to the downhole equipment using a screwdriver. The fixed end of the optoelectronic composite cable is connected to the surface system and the optical modulation / demodulation module via slip rings. The cable core of the optoelectronic composite cable is connected to the surface system, and the optical fiber is connected to the optical modulation / demodulation module. The optoelectronic composite cable is lowered using a winch system, and the dual-logging mode fiber optic sensing acoustic wave detection device is placed at a specific location in the well to begin detection. During the measurement process, the dual-logging mode fiber optic sensing acoustic wave detection device can be raised, lowered, or suspended. Based on the lowered length of the optoelectronic composite cable, the current well depth of the dual-logging mode fiber optic sensing acoustic wave detection device in the well to be logged can be determined.

[0182] Step 720: Send a transmission command to control the transmission line to provide a transmission drive signal to the transmitting acoustic system, so that the transmitting acoustic system amplifies the transmission drive signal provided by the transmission line and performs the excitation of acoustic waves, and acquires the scattered light signal coupled with the mechanical vibration caused by the acoustic waves collected by each acoustic wave receiving unit of the receiving acoustic system; wherein, the scattered light signal is the scattered light signal of the laser pulse transmitted through the optical fiber.

[0183] Specifically, the pulsed laser signal emitted by the pulsed laser modulation submodule enters the optical fiber connected to the optical fiber ring through the coupler. The beam splitter separates the backscattered Rayleigh light and sends it to the demodulation submodule, and stores the scattered light spectrum information of the demodulation submodule in the storage submodule.

[0184] The transmitting line responds to the transmission command by providing a transmission drive signal to the transmitting acoustic system. The transmitting acoustic system amplifies the transmission drive signal provided by the transmitting line and then performs an excitation operation based on the amplified transmission drive signal, thereby generating sound waves. After the sound waves are generated, the scattered light signals coupled with the mechanical vibrations caused by the sound waves are collected by the sound wave receiving units of the receiving acoustic system.

[0185] Specifically, the acoustic system signals can be transmitted in a specific timing sequence by synchronizing the transmission and reception times of the acoustic system sub-sub ...

[0186] A dual-logging-mode fiber optic sensing acoustic wave detection device sends a transmission command, which in turn drives the transmitting acoustic system to excite monopole, dipole, or quadrupole vibrations. The vibrations are transmitted to the formation through the wellbore fluid, emitted through geological anomalies, and return to the wellbore. The reflected waves act on each acoustic wave receiving unit, demodulate, and record the scattered light signals collected by each acoustic wave receiving unit under the disturbance of the reflected waves.

[0187] Step 730: Based on the scattered light signals collected by each acoustic wave receiving unit, determine the strain generated by the fiber optic ring of each acoustic wave receiving unit at the current well depth using a preset strain determination method.

[0188] Optionally, the method for determining the predefined strain may include time-domain localization and frequency-domain analysis methods.

[0189] Furthermore, time-domain positioning and frequency-domain analysis methods can be used to obtain the strain of the optical fiber at one or more depth locations.

[0190] Step 740: Based on the strain generated by the fiber optic ring of each acoustic receiving unit, generate the waveform curve corresponding to each acoustic receiving unit by plotting, and determine the wave impedance imaging result of the formation around the well at the current well depth based on all the waveform curves through a preset processing method.

[0191] Among them, the waveform curve is the curve of amplitude changing with time, and the origin of the coordinate system can be regarded as the excitation start time.

[0192] Optionally, steps 710 to 740 are repeated when the dual-logging mode fiber optic sensing acoustic detection device is located at different depths inside the wellbore, thereby obtaining acoustic logging data corresponding to multiple depths.

[0193] Optionally, the acoustic wave amplitude signals collected by each channel of the acoustic receiving system at different depths are processed by deconvolution, amplitude compensation, frequency domain filtering, wave field separation, and offset imaging to obtain wave impedance imaging results in all directions around the well.

[0194] In some embodiments, the dual-logging-mode fiber optic sensing acoustic detection device is connected via an armored cable or drill pipe, and the method further includes:

[0195] By controlling the lifting or lowering of the armored cable or drill pipe, the position of the dual-logging-mode fiber optic sensing acoustic detection device in the well to be logged can be controlled.

[0196] Specifically, by lifting or lowering the optical fiber composite cable, the position of the dual-logging mode fiber optic sensing acoustic wave detection device in the well to be logged can be changed. After reaching the predetermined position, the dual-logging mode fiber optic sensing acoustic wave detection device can be suspended at the current position.

[0197] Example 7

[0198] Based on the above embodiments, this embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the above embodiments.

[0199] In some embodiments of this example, a computer-readable storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the steps of the method described in the above embodiments.

[0200] In some embodiments of this example, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps of the method described in the above embodiments.

[0201] The processor may include, but is not limited to, one or more processors or microprocessors. Each processor may be implemented as an Application Specific Integrated Circuit (ASIC), Digital Signal Processor (DSP), Digital Signal Processing Device (DSPD), Programmable Logic Device (PLD), Field Programmable Gate Array (FPGA), controller, microcontroller, microprocessor, or other electronic component, for executing the methods in the above embodiments.

[0202] Computer-readable storage media can be implemented by any type of volatile or non-volatile storage device or a combination thereof. Computer-readable storage media may include, but are not limited to, random access memory (RAM), read-only memory (ROM), flash memory, EPROM memory, EEPROM memory, registers, computer storage media (e.g., hard disk, floppy disk, solid-state drive, removable disk, CD-ROM, DVD-ROM, Blu-ray disc, etc.).

[0203] Computer-readable storage media may also store at least one computer-executable program, such as computer-readable instructions. Computer-readable storage media include, but are not limited to, volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Computer-readable storage media may include, for example, read-only memory (ROM), hard disk, flash memory, etc. For example, a non-transitory computer-readable storage medium may be connected to a computing device such as a computer, and then, when the computing device executes the computer-readable instructions stored on the computer-readable storage medium, the various methods described above can be performed.

[0204] In addition, the computer device may include (but is not limited to) a data bus, an input / output (I / O) bus, a display, and input / output devices (e.g., keyboard, mouse, speakers, etc.).

[0205] The processor can communicate with external devices via the I / O bus through wired or wireless networks.

[0206] In one embodiment, the at least one computer-executable instruction may also be compiled into or comprise a software product / computer program product, wherein one or more computer-executable instructions are executed by a processor to perform the steps of the various functions and / or methods in the embodiments described herein.

[0207] It should be understood that the terms "mechanism," "device," "component," etc., used in this application are merely one method of distinguishing different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they can be replaced by other expressions.

[0208] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention. In practical applications, the technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification, and various changes can be made to them in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A dual-logging-mode fiber optic sensing acoustic detection device, characterized in that, include: Dual-logging mode fiber optic sensing acoustic wave detection device body; The power supply module is located inside the dual-logging-mode fiber optic sensing acoustic wave detection device. It is used to provide power to the measurement control module, transmission line, transmission acoustic system and optical modulation and demodulation module located inside the dual-logging-mode fiber optic sensing acoustic wave detection device by directly powering the device through a battery stub or by converting externally supplied power through a power adapter stub. The measurement and control module, connected to the optical modulation and demodulation module and the transmitting acoustic system, is used to issue pulse transmission commands to control the optical modulation and demodulation module to perform the operation of transmitting laser pulse signals, and to issue transmission commands to control the transmission line to provide transmission drive signals to the transmitting acoustic system; The transmitting line is located inside the body of the dual-logging-mode fiber optic sensing acoustic wave detection device and connected to the measurement and control module. It is used to provide a transmitting drive signal to the transmitting acoustic system in response to the transmitting command sent by the measurement and control module. The transmitting acoustic system is located inside the body of the dual-logging-mode fiber optic sensing acoustic wave detection device and is connected to the transmitting line. It is used to amplify the transmitting drive signal provided by the transmitting line and perform the excitation acoustic wave operation. A sound insulation body is disposed between the transmitting sound system and the receiving sound system to block the direct wave excited by the transmitting sound system and propagating along the outer shell of the dual logging mode fiber optic sensing acoustic wave detection device. The receiving acoustic system is located inside the body of the dual-logging mode fiber optic sensing acoustic wave detection device and is connected to the optical modulation and demodulation module via an optical fiber. The optical fiber is used to conduct the laser pulse signal. The receiving acoustic system is used to enhance the sensitivity of weak acoustic signals from the outside so that the optical fiber located inside the receiving acoustic system is disturbed, thereby coupling the mechanical vibration caused by the weak acoustic signal into the scattered light signal of the laser pulse signal. The optical modulation and demodulation module is used to perform the operation of emitting a laser pulse signal into the optical fiber in response to the pulse emission command, and to demodulate the scattered light signal to obtain spectral data.

2. The apparatus according to claim 1, characterized in that, The transmitting acoustic system includes a boost unit and a transmitting transducer; wherein: The boost unit is used to amplify the transmission drive signal provided by the transmission line, thereby driving the transmission transducer to vibrate; The transmitting transducer is used to convert electrical energy into mechanical energy according to the amplified transmitting drive signal, and then excite sound waves through vibration; wherein, the transmitting transducer includes: One or more of the following: monopole emitter transducer, dipole emitter transducer, and quadrupole emitter transducer.

3. The apparatus according to claim 1, characterized in that, The acoustic receiving system includes multiple acoustic receiving units, and each acoustic receiving unit is provided with an optical fiber ring support. The optical fiber is wound layer by layer on the optical fiber ring support according to a preset winding strategy along the axis of the dual logging mode optical fiber sensing acoustic wave detection device to form an optical fiber ring.

4. The apparatus according to claim 3, characterized in that, The fiber optic ring support is cylindrical, and the preset winding strategy includes a uniform winding strategy, which includes: At any position along the axis of the dual-logging mode fiber optic sensing acoustic wave detection device, the number of turns of the fiber optic ring is the same at any location on the fiber optic ring support.

5. The apparatus according to claim 3, characterized in that, The fiber optic ring support is cylindrical, and the preset winding strategy includes a non-uniform winding strategy, which includes: With the optical fiber ring support at the midpoint of the axis of the dual-logging mode optical fiber sensing acoustic wave detection device as the center, the number of turns of the optical fiber ring decreases sequentially along the axis of the dual-logging mode optical fiber sensing acoustic wave detection device.

6. The apparatus according to claim 1, characterized in that, The optical modulation and demodulation module includes: The storage submodule is used to store the spectral data obtained by the optical modulation and demodulation module.

7. The apparatus according to claim 1, characterized in that, The optical fiber is a single-mode optical fiber.

8. The apparatus according to claim 7, characterized in that, The scattered light signal is a backscattered Rayleigh light signal.

9. A control method for the dual-logging-mode fiber optic sensing acoustic detection device according to any one of claims 1 to 8, characterized in that, The method includes: Determine the current well depth at which the dual-logging mode fiber optic sensing acoustic detection device is located in the well to be logged; A transmission command is sent to control the transmission line to provide a transmission drive signal to the transmission acoustic system, so that the transmission acoustic system amplifies the transmission drive signal provided by the transmission line and performs an excitation sound wave operation, and acquires the scattered light signal coupled with the mechanical vibration caused by the sound wave collected by each sound wave receiving unit of the receiving acoustic system; wherein, the scattered light signal is the scattered light signal of the laser pulse transmitted through the optical fiber; Based on the scattered light signals collected by each acoustic wave receiving unit, the strain generated by the fiber optic ring of each acoustic wave receiving unit at the current well depth is determined by a preset strain determination method. Based on the strain generated by the fiber optic ring of each acoustic receiving unit, waveform curves corresponding to each acoustic receiving unit are generated by plotting. Based on all the waveform curves, the wave impedance imaging results of the formation around the well to be measured at the current well depth are determined by a preset processing method.

10. The method according to claim 9, characterized in that, The method further includes connecting the dual-logging-mode fiber optic sensing acoustic detection device via armored cable or drill pipe: By controlling the lifting or lowering of the armored cable or drill pipe, the position of the dual-logging-mode fiber optic sensing acoustic detection device in the well to be logged can be controlled.

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