Multi-scale while-drilling acoustic imaging logging device and method

Abstract

The invention provides a multi-scale while-drilling acoustic imaging logging device and method. An eccentric acoustic logging acoustic system and an active transmitting and receiving ultrasonic logging acoustic system are oppositely embedded in the outer side face of a drill collar. The eccentric acoustic logging acoustic system measures radial and circumferential acoustic characteristics of medium and long-distance stratums in an eccentric transmitting and receiving mode; the active transmitting and receiving ultrasonic logging acoustic system measures circumferential acoustic characteristics of a near-well-wall stratum in an up-down transmitting and middle compensation receiving mode; determining real-time azimuth information of rotation of the device by using an azimuth detection module; the main control electronic bin is in communication connection with all the substructures, transmits instructions and obtains sound waves, ultrasonic pulse waves and azimuth information, and sound velocity imaging data of near-well-wall stratums and medium-long-distance stratums are formed. By applying the device, the problems of small detection range, low measurement resolution, poor imaging precision, single measurement information and the like in the prior art can be solved, and comprehensive and fine evaluation on heterogeneity and anisotropy of underground geology and accurate detection on anomalous bodies can be synchronously realized.

Description

Technical Field

[0001] The present invention relates to the technical field of oil exploration and development, mainly to the technical field of oil imaging logging, and in particular to a multi-scale while-drilling acoustic imaging logging device and method. Background Art

[0002] The emergence of a large number of horizontal wells and high-angle wells has accelerated the intensity and scale of exploration and development of unconventional oil and gas resources such as shale gas, shale oil, tight gas, and tight oil. Unconventional oil and gas resources have low grade, dense reservoirs, complex lithology, many thin interlayers, and strong heterogeneity and anisotropy. These geological characteristics determine that they have special needs for logging technology, and the logging technology used is significantly different from that of conventional oil and gas resources. Conventional oil and gas logging technology is difficult to meet the technical needs of unconventional oil and gas exploration and development. It is urgent to develop new technologies and methods for unconventional oil and gas logging to solve a series of technical challenges in unconventional oil and gas exploration and development. Formation lithology, heterogeneity, and rock brittleness are closely related to the characteristics of formation sound velocity. Therefore, formation sound velocity logging technology is one of the new directions for the development of unconventional oil and gas logging technology.

[0003] In the related prior art, although conventional formation sonic velocity logging technology has the advantage of deep detection depth, it has the defect of low measurement resolution; while ultrasonic formation sonic velocity logging technology uses ultrasonic waves as carriers and adopts ultrasonic pulse refraction method to generate formation sliding waves propagating along the well wall formation, and obtains acoustic information such as sound velocity and attenuation of the well wall formation by collecting and processing these sliding waves, so as to evaluate the elastic parameters and mechanical properties of the well wall medium; although dual ultrasonic imaging logging instruments have been introduced in the field to achieve high-resolution formation sonic velocity imaging logging, it can solve the problem of fine evaluation of heterogeneous thin interlayer reservoirs to a certain extent. Compared with conventional formation sonic velocity logging, the use of ultrasonic formation sonic velocity logging to evaluate the heterogeneity and anisotropy of unconventional reservoirs can effectively improve the measurement resolution and imaging accuracy, and its spatial resolution can reach the millimeter level, which is particularly suitable for evaluating the rock mechanical properties and well wall stress distribution of unconventional reservoirs. However, the ultrasonic formation sound velocity logging technology has a shallow detection depth due to its high working frequency and large attenuation. It can only detect the surface area of ​​the well wall medium and cannot detect the sound velocity information of distant formations. It has great limitations and is not conducive to describing the lateral changes of the reservoir.

[0004] It can be seen that the existing ultrasonic formation sound velocity logging has the advantages of high measurement resolution and high imaging accuracy, but has the defect of shallow detection depth. Whether it is ultrasonic formation sound velocity logging or conventional formation sound velocity logging, a single logging information cannot realize multi-scale and high-precision formation sound velocity information monitoring, and cannot fully meet the technical requirements of unconventional oil and gas reservoir logging evaluation.

[0005] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art known to those skilled in the art. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a multi-scale acoustic imaging logging while drilling device. On the one hand, the multi-scale acoustic imaging logging while drilling device adopts an ultrasonic logging system to measure the circumferential acoustic characteristics of the formation near the wellbore wall; on the other hand, the multi-scale acoustic imaging logging while drilling device adopts an eccentric acoustic wave logging system to measure the radial and circumferential acoustic characteristics of the formation at medium and long distances; it is suitable for fine evaluation of the circumferential heterogeneity and anisotropy of the formation from near the wellbore wall to medium and long distances under the logging while drilling condition and accurate detection of geological anomalies outside the well. In one embodiment, the device includes: a drill collar, an eccentric acoustic wave logging system, an active transmitting and receiving ultrasonic logging system, an azimuth detection module and a main control electronic compartment;

[0007] The eccentric acoustic logging system and the active transmitting and receiving ultrasonic logging system are respectively arranged on the opposite outer sides of the drill collar in an embedded manner; the drill collar is a non-magnetic drill collar;

[0008] The eccentric acoustic logging acoustic system includes a polariton active transmitter, a strip-type active receiver array and a sound insulator structure, and is used to measure radial and circumferential acoustic characteristics of formations at medium and long distances from the wellbore wall in response to control instructions through eccentric directional transmission and reception modes;

[0009] The active transmitting and receiving ultrasonic logging acoustic system comprises an upper ultrasonic transmitting probe, a lower ultrasonic transmitting probe, an ultrasonic receiver array and an ultrasonic transmitting and collecting circuit, and is used to measure the circumferential acoustic characteristics of the formation near the well wall through the upper and lower transmitting and intermediate compensation receiving mode;

[0010] The azimuth detection module is nested on the outer wall of the drill collar and is used to determine the azimuth information of the rotation of the device at the real-time measurement moment;

[0011] The main control electronic compartment is nested and sealed inside the drill collar, and is respectively communicated with the eccentric acoustic logging system, the active transmitting and receiving ultrasonic logging system and the azimuth detection module to convey work instructions and obtain acoustic waveforms, ultrasonic waveforms and device azimuth information to form sound velocity imaging data of near-wellbore wall formations and medium- and long-distance formations.

[0012] Preferably, in one embodiment, the polariton active transmitter comprises an arc-shaped sheet-shaped transmitting transducer and a high-voltage excitation circuit, which is used to transmit an acoustic pulse signal in the drilling fluid in the well to the formation outside the well;

[0013] The strip-type active receiver array is on the same side as the polariton active transmitter but axially spaced a certain distance apart, and comprises a plurality of receiving transducers and an acoustic wave collection circuit, and is used to synchronously receive the full wave train waveform of the acoustic wave pulse returned from the formation outside the well in the drilling fluid in the well.

[0014] In an optional embodiment, the receiving transducers of the strip-type active receiver array are all rectangular plate-shaped receiving transducers, the sound wave collection circuit is arranged between two adjacent rectangular plate-shaped receiving transducers, and every two rectangular plate-shaped receiving transducers share one sound wave collection circuit.

[0015] Optionally, in one embodiment, the sound insulation structure is formed by opening a plurality of periodic grooves or holes on the outer wall of the drill collar between the polariton active transmitter and the strip-type active receiver array, and applying vulcanized rubber thereon.

[0016] Furthermore, in one embodiment, the upper ultrasonic transmitting probe and the lower ultrasonic transmitting probe of the active transmitting and receiving ultrasonic logging acoustic system are respectively located at the upper and lower parts of the active transmitting and receiving ultrasonic logging acoustic system, and the ultrasonic receiver array and the ultrasonic transmitting and collecting circuit are located in the middle part of the active transmitting and receiving ultrasonic logging acoustic system.

[0017] In a preferred embodiment, the upper ultrasonic transmitting probe and the lower ultrasonic transmitting probe both use high-power ultrasonic cylindrical piezoelectric transducers;

[0018] The ultrasonic receiver array comprises a plurality of receiving probes arranged axially at equal intervals, and the receiving probes all adopt broadband high-sensitivity ultrasonic composite piezoelectric transducers.

[0019] Furthermore, in one embodiment, the azimuth detection module includes a dual-axis magnetoresistive sensor and a detection circuit, which are nested on the outer wall of the drill collar on the same side as the active transceiver ultrasonic logging acoustic system, and collects magnetic tool face angle information to determine the azimuth information of the device rotation at the time of real-time measurement.

[0020] Based on the application aspects of the device described in any one or more of the above embodiments, the present invention also provides a multi-scale acoustic imaging logging while drilling method, the method comprising:

[0021] Startup and self-checking steps: lower the configured multi-scale acoustic imaging logging device while drilling into a wellbore filled with drilling fluid, automatically execute the self-checking program after starting in response to the ground start command, and enter the working mode after the self-checking is completed;

[0022] Multi-mode detection step: in response to the set timing instruction, the device is controlled to start the eccentric acoustic logging system or the active ultrasonic logging system in the set drilling azimuth to realize the acoustic wave or ultrasonic pulse transmission operation and the corresponding reflected wave or refracted wave signal reception operation, and the azimuth information of the device is obtained through the azimuth detection module during the operation, and the reflected wave or refracted wave signal and the azimuth signal during the operation are transmitted to the main control electronic compartment;

[0023] Acoustic information analysis steps: The main control electronic warehouse reads the full wave train waveform of the acoustic wave and the ultrasonic pulse wave train, and uses a multi-channel waveform similarity correlation algorithm to obtain the formation acoustic information of the formation outside the well and the formation near the well wall respectively. Combined with the azimuth information, radial tomography images and circumferential azimuth images of the sound velocity of the medium and long-distance formations, as well as circumferential azimuth images of the sound velocity of the formation near the well wall are formed.

[0024] Furthermore, in a preferred embodiment, in the multi-mode detection step, at a certain moment, the polariton active transmitter transmits an acoustic wave pulse in a direction toward the formation outside the well on one side of the drill collar in the drilling fluid medium in the well, and the acoustic wave pulse propagates along a certain direction of the formation outside the well and continuously refracts or reflects back into the drilling fluid in the well;

[0025] At the next moment, the upper and lower ultrasonic transmitting probes simultaneously transmit ultrasonic pulse waves in the drilling fluid in the well to the near-wellbore wall formation on the other side of the drill collar. The ultrasonic pulse waves propagate in a certain direction of the near-wellbore wall formation and continuously refract back into the drilling fluid in the well.

[0026] Based on other aspects of the method described in any one or more of the above embodiments, the present invention further provides a storage medium storing program codes that are expected to implement the method described in any one or more of the above embodiments.

[0027] Compared with the closest prior art, the present invention also has the following beneficial effects:

[0028] The present invention provides a multi-scale acoustic imaging logging device and method while drilling, wherein an eccentric acoustic logging system and an active transmitting and receiving ultrasonic logging system are relatively embedded on the outer side of a drill collar; the eccentric acoustic logging system comprises a polarized active transmitter, a strip-type active receiver array and a sound insulation structure, and measures the radial and circumferential acoustic characteristics of formations at medium and long distances from the well wall in response to control instructions through an eccentric directional transmitting and receiving mode; the active transmitting and receiving ultrasonic logging system measures the circumferential acoustic characteristics of formations near the well wall through an up-and-down transmitting and intermediate compensating receiving mode; on the one hand, an ultrasonic logging system is used to measure the circumferential acoustic characteristics of formations near the well wall; on the other hand, the multi-scale acoustic imaging logging device while drilling provides uses an eccentric acoustic logging system to measure the radial and circumferential acoustic characteristics of formations at medium and long distances, and does not affect the strength and voltage stabilizing function of the non-magnetic drill collar during operation;

[0029] The azimuth detection module is used to determine the azimuth information of the device rotation at the real-time measurement moment; the real-time measured rotation azimuth angle is combined with the reflected wave or refracted wave signal obtained by acoustic wave measurement and ultrasonic measurement to form the circumferential precise sound velocity logging data of the measured formation and form a circumferential logging image.

[0030] The main control electronic warehouse is connected to each substructure in communication, conveys work instructions and obtains acoustic waveforms, ultrasonic waveforms and device orientation information to form sound velocity imaging data of near-well wall strata and medium- and long-distance strata; the application of this device effectively overcomes the problems of small detection range, low measurement resolution, poor imaging accuracy and single measurement information in the prior art, and can independently realize automatic measurement in response to the set control timing instructions, realize synchronous comprehensive and detailed evaluation of the heterogeneity and anisotropy of downhole geology and accurate detection of abnormal bodies, evaluate the circumferential heterogeneity and anisotropy of near-well wall strata and strata outside the well, and identify geological abnormalities such as strata interfaces and cracks outside the well.

[0031] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0033] Figure 1 It is a schematic structural diagram of a multi-scale acoustic imaging logging while drilling device provided by an embodiment of the present invention;

[0034] Figure 2 Schematic diagram of application scenario setting of a multi-scale acoustic imaging logging while drilling device provided by an embodiment of the present invention;

[0035] Figure 3 (a) and Figure 3 (b) are schematic diagrams of the directivity of a mid-arc sheet-shaped transmitter and a rectangular plate-shaped receiver of a multi-scale acoustic imaging logging while drilling device provided by an embodiment of the present invention;

[0036] Figure 4 It is a schematic diagram of the operation flow of a multi-scale acoustic imaging logging while drilling method provided by another embodiment of the present invention. DETAILED DESCRIPTION

[0037] The following will describe the implementation methods of the present invention in detail in conjunction with the accompanying drawings and embodiments, so that the implementers of the present invention can fully understand how the present invention applies technical means to solve technical problems and achieve the implementation process of technical effects and implement the present invention specifically according to the above implementation process. It should be noted that as long as there is no conflict, the various embodiments and various features of the embodiments in the present invention can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0038] Although the flowcharts describe the operations as sequential processes, many of the operations may be performed in parallel, concurrently, or simultaneously. The order of the operations may be rearranged. A process may be terminated when its operations are completed, but may also have additional steps not included in the accompanying drawings. A process may correspond to a method, function, procedure, subroutine, subprogram, etc.

[0039] Computer devices include user devices and network devices. Among them, user devices or clients include but are not limited to computers, smart phones, PDAs, etc.; network devices include but are not limited to a single network server, a server group consisting of multiple network servers, or a cloud composed of a large number of computers or network servers based on cloud computing. Computer devices can be operated alone to implement the present invention, or they can be connected to the network and implement the present invention through interactive operations with other computer devices in the network. The network where the computer device is located includes but is not limited to the Internet, wide area network, metropolitan area network, local area network, VPN network, etc.

[0040] The terms "first", "second", etc. may be used herein to describe various units, but these units should not be limited by these terms, and these terms are used only to distinguish one unit from another unit. The term "and / or" used herein includes any and all combinations of one or more of the listed associated items. When a unit is referred to as being "connected" or "coupled" to another unit, it can be directly connected or coupled to the other unit, or there can be intermediate units.

[0041] The terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "one", "one" and "item" used herein are also intended to include plural numbers. It should also be understood that the terms "include" and / or "comprise" used herein specify the existence of stated features, integers, steps, operations, units and / or components, without excluding the existence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0042] With the substantial improvement of oil drilling level, a large number of horizontal wells and high-angle wells have emerged, which has accelerated the intensity and scale of exploration and development of unconventional oil and gas resources such as shale gas, shale oil, tight gas, and tight oil. Unconventional oil and gas resources have low grade, dense reservoirs, complex lithology, many thin interlayers, and strong heterogeneity and anisotropy. These geological characteristics determine that they have special needs for logging technology, and the logging technology used is significantly different from that of conventional oil and gas resources. Conventional oil and gas logging technology is difficult to meet the technical needs of unconventional oil and gas exploration and development. It is urgent to develop new technologies and methods for unconventional oil and gas logging to solve a series of technical challenges in unconventional oil and gas exploration and development. Formation lithology, heterogeneity and rock brittleness are closely related to formation sound velocity. Ultrasonic formation sound velocity logging technology is one of the new directions for the development of unconventional oil and gas logging technology.

[0043] Ultrasonic formation sound velocity logging technology uses ultrasonic waves as the carrier and adopts ultrasonic pulse refraction method to generate formation sliding waves that propagate along the well wall formation. By collecting and processing these sliding waves, acoustic information such as the sound velocity and attenuation of the well wall formation is obtained, thereby evaluating the elastic parameters and mechanical properties of the well wall medium.

[0044] In 2020, Schlumberger launched the dual ultrasonic imaging logging while drilling instrument, which achieved high-resolution formation sound velocity imaging logging and solved the problem of fine evaluation of heterogeneous thin interbedded reservoirs. Compared with conventional formation sound velocity logging, the use of ultrasonic formation sound velocity logging to evaluate the heterogeneity and anisotropy of unconventional reservoirs can significantly improve the measurement resolution and imaging accuracy. Its spatial resolution can reach the millimeter level, and it is particularly suitable for evaluating the rock mechanical properties and wellbore stress distribution of unconventional reservoirs. However, due to its high operating frequency and large attenuation, ultrasonic formation sound velocity logging has a shallow detection depth and can only detect the surface area of ​​the wellbore medium. It cannot detect the sound velocity information of distant formations. It has great limitations and is not conducive to describing the lateral changes of the reservoir.

[0045] Ultrasonic formation sound velocity logging has the advantages of high measurement resolution and high imaging accuracy, but has the disadvantage of shallow detection depth. Conventional formation sound velocity logging has the disadvantage of low measurement resolution, but has the advantage of deep detection depth. Therefore, whether it is ultrasonic formation sound velocity logging or conventional formation sound velocity logging, single logging information cannot fully meet the technical requirements of unconventional oil and gas reservoir logging evaluation.

[0046] To sum up, the development of multi-size, large detection range, and cross-frequency band formation sonic logging technology is an important direction of technical improvement. In order to overcome the above-mentioned defects of the prior art, the present invention provides a multi-scale downhole acoustic imaging logging device and method. The researchers of the present invention have considered that in the process of oil and gas logging data acquisition, according to a reasonable strategy combined with the application of adaptive technology, ultrasonic formation sonic logging and conventional formation sonic logging information are collected alternately in an orderly manner. By comprehensively utilizing the advantages of both, it is possible to achieve millimeter-level near-wellbore wall detection to centimeter-level medium and long-distance reservoir detection, thereby meeting the technical requirements of unconventional oil and gas logging evaluation and reservoir description.

[0047] The multi-scale acoustic imaging logging while drilling device and method provided by the present invention not only overcomes the shortcomings of small detection range, low measurement resolution, poor imaging accuracy and single measurement information in the evaluation of heterogeneity and anisotropy of unconventional reservoirs, but also solves the problem of extending the detection from near-wellbore wall to medium and long-distance formation detection at the same depth, thereby improving the ability of the formation acoustic velocity imaging logging while drilling technology to quantitatively evaluate and finely describe unconventional oil and gas reservoirs.

[0048] Next, the structural components, connection modes and functional principles of the device of the embodiment of the present invention are described in detail based on the drawings. Although the logical order of each operation is shown in the process of describing the operating principle of the device structure, in some cases, the operations shown or described can be performed in a different order than here.

[0049] Embodiment 1:

[0050] Figure 1 FIG. 1 shows a schematic diagram of the structure of a multi-scale acoustic imaging logging device while drilling provided by the first embodiment of the present invention, referring to FIG. Figure 1 It can be seen that the device includes: a drill collar, an eccentric acoustic logging system 1, an active transmitting and receiving ultrasonic logging system 2, an azimuth detection module 3 and a main control electronic compartment 4; wherein the drill collar adopts a non-magnetic drill collar;

[0051] The eccentric acoustic wave logging system and the active transmitting and receiving ultrasonic logging system are respectively arranged on the outer side of the drill collar in an embedded manner;

[0052] The eccentric acoustic logging acoustic system includes a polariton active transmitter, a strip-type active receiver array and a sound insulator structure, and is used to measure radial and circumferential acoustic characteristics of formations at medium and long distances from the wellbore wall in response to control instructions through eccentric directional transmission and reception modes;

[0053] The active transmitting and receiving ultrasonic logging acoustic system comprises an upper ultrasonic transmitting probe, a lower ultrasonic transmitting probe, an ultrasonic receiver array and an ultrasonic transmitting and collecting circuit, and is used to measure the circumferential acoustic characteristics of the formation near the well wall through the upper and lower transmitting and intermediate compensation receiving mode;

[0054] The azimuth detection module is nested on the outer wall of the drill collar and is used to determine the azimuth information of the rotation of the device at the real-time measurement moment;

[0055] The main control electronic compartment is nested and sealed inside the non-magnetic drill collar, and is respectively communicated with the eccentric acoustic logging system, the active transceiver ultrasonic logging system and the azimuth detection module to convey work instructions and obtain acoustic waveforms, ultrasonic waveforms and device azimuth information to form sound velocity imaging data of near-wellbore wall formations and medium- and long-distance formations.

[0056] In order to overcome the shortcomings of small detection range, low measurement resolution, poor imaging accuracy and single measurement information in the evaluation of heterogeneity and anisotropy of unconventional reservoirs, the embodiment of the present invention provides a multi-scale acoustic imaging logging device while drilling. By using this device, comprehensive detection can be achieved from near-wellbore wall detection to medium and long-distance formations at the same depth, effectively improving the ability of the formation acoustic velocity imaging logging technology while drilling to quantitatively evaluate and finely describe unconventional oil and gas reservoirs.

[0057] Specifically, Figure 2 The figure shows a schematic diagram of the application scenario of the multi-scale acoustic imaging logging device while drilling of the present invention. Figure 2 As shown, the multi-scale acoustic imaging logging device while drilling of the present invention uses a non-magnetic drill collar 5 as an installation support frame, and a plurality of groups of grooves or slots are provided on the side wall of the non-magnetic drill collar 5 along the axial direction for accommodating an eccentric acoustic wave logging system 1, an active transmitting and receiving ultrasonic logging system 2, an azimuth detection module 3 and a main control electronic compartment 4.

[0058] The polariton active transmitter 11, the strip-type active receiver array 12, and the sound insulator 13 form a one-transmit-multiple-receive eccentric acoustic wave logging acoustic system;

[0059] Specifically, in a preferred embodiment, the polariton active transmitter integrates an arc-shaped sheet-shaped transmitting transducer and a high-voltage excitation circuit, and is used to transmit an acoustic wave pulse signal in the drilling fluid in the well to the formation outside the well.

[0060] In actual application, the eccentric acoustic logging system 1 is integrally embedded in the outer wall of one side of the non-magnetic drill collar 5 to form an eccentric transmitting and receiving mode, adopting a one-transmit-multiple-receive structure, including a polariton active transmitter 11, a strip-type active receiver array 12, a sound insulator 13, etc.

[0061] The polariton active transmitter 11 integrates an arc-shaped sheet-shaped transmitting transducer 111 and a high-voltage excitation circuit 112, and is used to transmit an acoustic pulse signal in a certain direction in the well formation in the drilling fluid in the well. The arc-shaped sheet-shaped transmitting transducer 111 is encapsulated with non-conductive epoxy resin and rubber and is directly exposed in the drilling fluid in the well. The circular angle of the arc-shaped sheet-shaped transmitting transducer is 75° to 90° and the center frequency is 10kHz. The high-voltage excitation circuit 112 outputs a square wave pulse signal with an amplitude of 1000 to 2000V, which excites the arc-shaped sheet-shaped transmitting transducer 111 to generate an acoustic pulse signal with a frequency range of 8 to 12kHz.

[0062] The strip-type active receiver array is on the same side as the polarized active transmitter but axially spaced a certain distance apart, and comprises a plurality of receiving transducers and an acoustic wave acquisition circuit, which are used to synchronously receive the full wave train waveform of the acoustic wave pulse returned from the formation outside the well in the drilling fluid in the well, and directionally transmit the acoustic wave pulse signal to a certain direction of the formation outside the well.

[0063] The strip-type active receiver array is installed at a certain distance axially from the polarized active transmitter and is embedded in the outer wall of the same side of the non-magnetic drill collar. In a preferred embodiment, a strip-type active receiver array is provided, which integrates 8 or more rectangular plate-shaped receiving transducers and sound wave collection circuits distributed axially at equal intervals, and is used to receive and collect the full wave train waveform of the sound wave pulse returned from a certain direction of the formation outside the well in the drilling fluid in the well.

[0064] In actual application, in a preferred embodiment, the receiving transducers of the strip-type active receiver array are all rectangular plate-shaped receiving transducers, and the sound wave collection circuit is arranged between two adjacent rectangular plate-shaped receiving transducers, and every two rectangular plate-shaped receiving transducers share a two-channel sound wave collection circuit.

[0065] like Figure 2As shown, the strip-type active receiver array 12 integrates 8 or more rectangular plate-shaped receiving transducers 121 and sound wave collection circuits 122 that are evenly spaced in the axial direction, and is used to receive and collect the full wave waveform of sound waves including formation longitudinal waves, transverse waves, Stoneley waves, reflected waves, etc. returned from a certain direction of the formation outside the well in the drilling fluid in the well. The strip-type active receiver array 12 is packaged in a long strip metal shell with an outer arc surface, and the shell is filled with silicone oil to maintain the balance of internal and external pressures. The strip-type active receiver array 12 is installed at a position at least 3m apart from the polarized active transmitter 11 in the axial direction. The rectangular plate-shaped receiving transducer 121 is fixed inside the metal shell by single-end clamping and rubber sleeve surrounding. The distance between two adjacent rectangular plate-shaped receiving transducers 121 is 0.15 to 0.30m, and the bandwidth of the rectangular plate-shaped receiving transducer 121 is 1 to 35kHz. The sound wave collection circuit 122 is arranged between two adjacent rectangular plate-shaped receiving transducers 121, and each two rectangular plate-shaped receiving transducers 121 share a two-channel sound wave collection circuit 122. There are at least four two-channel sound wave collection circuits 122 in total, with a sampling frequency of 500kHz and a sampling accuracy of 14bit.

[0066] The sound insulator structure is arranged between the polariton active transmitter and the strip-type active receiver array, and is used to attenuate the direct wave signal of the sound wave propagating along the surface of the drill collar. In a preferred embodiment, the sound insulator structure is arranged between the polariton active transmitter and the strip-type active receiver array and is embedded in the outer wall of the drill collar on the same side as them. Specifically, 10 or more periodic grooves or holes can be arranged inside the sound insulator structure to attenuate the direct wave signal of the sound wave propagating along the surface of the drill collar.

[0067] In a preferred embodiment, the sound insulation structure can be formed by opening a plurality of periodic grooves or holes on the outer wall of the drill collar between the polariton active transmitter and the strip-type active receiver array, and applying vulcanized rubber on the outer wall. Figure 2 As shown, 10 or more periodic grooves or holes are opened on the outer wall of the same side of the non-magnetic drill collar 5 directly between the polariton active transmitter 11 and the strip-type active receiver array 12, and the grooves or holes are coated with vulcanized rubber as a sound insulation structure for attenuating the direct wave signal of the sound wave propagating along the surface of the drill collar.

[0068] Preferably, the depth of the groove or hole is about 2 to 2.5 cm, the stopband frequency range of the sound insulation structure 13 is 7 to 15 kHz, and the sound attenuation is above 20 dB, which ensures the attenuation effect of the target signal while having excellent firmness and is not easily affected by wear and tear during operation.

[0069] The upper ultrasonic transmitting probe and the lower ultrasonic transmitting probe of the active transmitting and receiving ultrasonic logging acoustic system are respectively located at the upper part and the lower part of the active transmitting and receiving ultrasonic logging acoustic system, and the ultrasonic receiver array and the ultrasonic transmitting and collecting circuit are located in the middle part of the active transmitting and receiving ultrasonic logging acoustic system.

[0070] Furthermore, the active ultrasonic logging acoustic system adopts the upper and lower transmission and middle compensation reception mode to form a dual-transmission and four-receiver ultrasonic logging acoustic system. The active ultrasonic logging acoustic system is nested in the outer wall of the other side of the non-magnetic drill collar opposite to the strip-type active receiver array, and integrates upper and lower ultrasonic transmitting probes, ultrasonic receiver arrays and ultrasonic transmitting and collecting circuits, which are used to transmit ultrasonic pulse signals to the formation near the well wall in the drilling fluid in the well and receive and collect the full wave train waveform of ultrasonic pulses returned from this area.

[0071] In a preferred embodiment, the upper ultrasonic transmitting probe and the lower ultrasonic transmitting probe of the active ultrasonic logging acoustic system both use high-power ultrasonic cylindrical piezoelectric transducers; the ultrasonic receiver array includes a plurality of receiving probes arranged axially at equal intervals, and the receiving probes all use broadband high-sensitivity ultrasonic composite piezoelectric transducers.

[0072] In actual application, the active transmitting and receiving ultrasonic logging acoustic system 2 is integrally embedded in the outer wall of the other side of the non-magnetic drill collar 5, and adopts a double transmitting and four receiving structure, such as Figure 2 As shown, specifically, the active transceiver ultrasonic logging acoustic system 2 comprises an upper ultrasonic transmitting probe 21, a lower ultrasonic transmitting probe 22, an ultrasonic receiver array 23, and an ultrasonic transmitting and collecting circuit 24, etc. Among them, the upper ultrasonic transmitting and ultrasonic measuring probe 21 is located at the upper part of the active transceiver ultrasonic logging acoustic system 2, the lower ultrasonic transmitting probe 22 is located at the lower part of the active transceiver ultrasonic logging acoustic system 2, and the ultrasonic receiver array 23 and the ultrasonic transmitting and collecting circuit 24 are located in the middle part of the active transceiver ultrasonic logging acoustic system 2.

[0073] The upper ultrasonic transmitting probe 21 and the lower ultrasonic transmitting probe 22 are both high-power ultrasonic cylindrical piezoelectric transducers with good performance consistency. They can emit ultrasonic pulse waves under the action of high-voltage excitation pulses, and the main frequency of the ultrasonic pulse waves is around 160kHz. The ultrasonic receiver array 23 includes 4 receiving probes arranged axially at equal intervals. The receiving probes are all broadband high-sensitivity ultrasonic composite piezoelectric transducers with good consistency. They can receive ultrasonic pulse waveforms in the ultrasonic frequency range of 100 to 300kHz. The ultrasonic transmitting acquisition circuit 24 includes two excitation circuits and four acquisition circuits. The excitation circuit outputs a sharp pulse signal with an amplitude of 200 to 400V. The sampling frequency of the acquisition circuit is 2.5MHz, and the acquisition accuracy is 16bit.

[0074] The azimuth detection module includes a dual-axis magnetoresistive sensor and a detection circuit, which are nested on the outer wall of the drill collar on the same side as the active transceiver ultrasonic logging acoustic system, and collects magnetic tool face angle information to determine the azimuth information of the device rotation at the real-time measurement moment. Specifically, the azimuth detection module obtains the magnetic tool face angle through the dual-axis magnetoresistive sensor and the detection circuit to determine the azimuth angle of rotation of the imaging logging device at the current measurement moment.

[0075] Specifically, in an optional embodiment, the azimuth detection module 3 integrates a dual-axis magnetoresistive sensor and a detection circuit, which is nested in the outer wall of the non-magnetic drill collar 5 on the same side as the active transceiver ultrasonic logging acoustic system 2, and is used to obtain the magnetic tool face angle to determine the azimuth angle of rotation of the imaging logging device at the current measurement moment. The dual-axis magnetoresistive sensor has the ability to sense changes in magnetic fields in mutually perpendicular directions, and the magnetic tool face angle measurement range is 0 to 360°, with a detection accuracy of ±1°.

[0076] The main control electronic compartment 4 is nested and sealed inside the non-magnetic drill collar, and is electrically connected to the polar active transmitter, the strip active receiver array, the active transmitting and receiving ultrasonic logging acoustic system 2, and the azimuth detection module 3, and is used to send the timing instructions for the logging work of the imaging logging device and receive, process and analyze the full wave train waveform of the acoustic pulse and the full wave train waveform of the ultrasonic pulse to form a circumferential azimuth imaging map of the near-wellbore wall formation sound velocity and a radial tomographic imaging map and a circumferential azimuth imaging map of the medium and long-distance formation sound velocity.

[0077] In actual application, the main control electronic compartment 4 is used to control the logging work timing instructions of the eccentric acoustic logging system 1, the active ultrasonic logging system 2 and the azimuth detection module 3 when it rotates to the corresponding azimuth; and analyze and process the full wave train waveform of the acoustic wave pulses including the formation longitudinal wave, transverse wave, Stoneley wave, and reflection wave collected by the eccentric acoustic logging system 1 and the ultrasonic pulse wave train including the formation longitudinal wave, transverse wave, Stoneley wave, and the like collected by the active ultrasonic logging system 2. Combined with the measured azimuth, radial tomography images and circumferential azimuth images of the sound velocity of the medium and long distance formations and circumferential azimuth images of the sound velocity of the near-wellbore wall formations can be obtained respectively.

[0078] In actual application, in order to ensure that the main control electronic warehouse can accurately control the rotation to the corresponding position according to the timing instructions, the eccentric sonic logging sound system, the active ultrasonic logging sound system and the azimuth detection module are controlled, in a preferred embodiment, the rotation speed of the drill collar in different working conditions of the current logging project is pre-set, and the sonic logging timing instructions for the matching time period are stored in the main control electronic warehouse. After the device is completed in the well self-inspection, the main control electronic warehouse autonomously controls other substructures according to the preset timing instructions to carry out sonic logging operations.

[0079] Specifically, Figure 2As shown, the main control electronic compartment 4 is nested and sealed inside the non-magnetic drill collar, and is electrically connected to the external power supply short section and telemetry short section through a pressure-bearing sealed connector. A control processing unit with a CPU as the core is integrated inside, and data communication is carried out with the polar active transmitter 11, the strip active receiver array 12, the active transmitting and receiving ultrasonic logging acoustic system 2, the azimuth detection module 3, etc. through a serial bus, and is used to send working timing instructions and receive, process and analyze the full wave train waveform of the acoustic pulse and the ultrasonic pulse waveform, so as to obtain the circumferential azimuth imaging diagram of the near-wellbore wall formation sound velocity and the radial tomography imaging diagram and circumferential azimuth imaging diagram of the medium and long-distance formation sound velocity.

[0080] The multi-scale acoustic imaging logging device while drilling of the present invention is located in the drilling fluid in the well. The eccentric acoustic wave logging system 1 and the active transmitting and receiving ultrasonic logging system 2 perform the formation sound velocity logging while drilling alternately according to the preset timing instructions, and follow the rotation of the non-magnetic drill collar 5, so as to realize the three-dimensional scanning imaging from the near-wellbore wall formation to the medium- and long-distance formation within the 360° range of the whole wellbore, thereby obtaining the circumferential azimuth imaging map of the near-wellbore wall formation sound velocity and the radial tomographic imaging map and circumferential azimuth imaging map of the medium- and long-distance formation sound velocity.

[0081] The eccentric acoustic logging system 1 uses directional transmission and reception technology to scan and measure the formation outside the well, and has a high azimuth resolution capability. Figure 3 (a) and Figure 3 (b) respectively show the directivity diagrams of the arc-shaped sheet transmitter 111 and the rectangular plate receiver 121 in the multi-scale acoustic imaging logging device while drilling of the present invention. Due to the shielding effect of the non-magnetic drill collar 5 on the acoustic wave signal, the energy of the acoustic wave emitted to the opposite side by the arc-shaped sheet transmitter 111 located on one side of the non-magnetic drill collar 5 is reduced, so that the arc-shaped sheet transmitter 111 has an azimuth resolution feature in the circumferential direction. Similarly, the rectangular plate receiver 121 located on the same side of the non-magnetic drill collar 5 as the arc-shaped sheet transmitter 111 can only receive the acoustic wave signal refracted or reflected from the outer formation on the same side of the non-magnetic drill collar 5 due to the acoustic shielding effect of the non-magnetic drill collar, so that the rectangular plate receiver 121 also has an azimuth resolution feature in the circumferential direction. The 3dB main lobe angular width of the radiated sound beam of the arc-shaped sheet transmitter 111 is 60°~65°, and it can radiate sound wave energy in a certain direction with a certain angular width; the 3dB angular width of the receiving sound beam of the rectangular plate receiver 121 is 80°~85°, and it can form a directional beam in a certain direction with a certain angular width.

[0082] Well logging is realized by utilizing the multi-scale acoustic imaging logging device while drilling, and formation sound velocity imaging logging while drilling is performed alternately in the ultrasonic frequency band and the audio frequency band, so that the circumferential azimuth imaging of the sound velocity of the formation near the well wall can be extended to the radial tomography imaging and circumferential azimuth imaging of the sound velocity of the formation at medium and long distances during the logging while drilling process, so as to evaluate the circumferential heterogeneity and anisotropy of the formation near the well wall and the formation outside the well, and to identify geological anomalies such as the formation interface and cracks outside the well, and both the ultrasonic logging acoustic system and the eccentric acoustic wave logging acoustic system are installed in the non-magnetic drill collar, and basically do not affect the strength and voltage stabilization function of the non-magnetic drill collar.

[0083] In actual application, the multi-scale acoustic imaging logging while drilling device of the present invention is configured at the wellhead, the timing instructions for logging work are set, and the multi-scale acoustic imaging logging while drilling device of the present invention is lowered into the wellbore filled with drilling fluid through the drilling tool assembly. The ground start-up instruction is transmitted to the acoustic imaging logging while drilling device of the present invention through the drilling fluid, and the multi-scale acoustic imaging logging while drilling device of the present invention is started to perform self-checking. After the self-checking is successful, the multi-scale acoustic imaging logging while drilling device of the present invention enters the logging while drilling working state according to the preset timing instructions. The provided multi-scale acoustic imaging logging while drilling method can perform formation sound velocity imaging logging while drilling alternately in the audio frequency band and the ultrasonic frequency band during the drilling process.

[0084] In the multi-scale acoustic imaging logging while drilling device provided by the embodiment of the present invention, each module or unit structure can be operated independently or in combination according to the actual structural layout requirements and data processing requirements to achieve corresponding technical effects.

[0085] Embodiment 2:

[0086] The device is described in detail in the embodiments disclosed in the above invention. Based on other aspects of the device described in any one or more embodiments, the present invention also provides a multi-scale acoustic imaging logging while drilling method, which is applied to the multi-scale acoustic imaging logging while drilling device described in any one or more embodiments. Specific embodiments are given below for detailed description.

[0087] The multi-scale acoustic imaging logging while drilling method provided in the embodiment of the present invention includes:

[0088] Startup and self-checking steps: lower the configured multi-scale acoustic imaging logging device while drilling into a wellbore filled with drilling fluid, automatically execute the self-checking program after starting in response to the ground start command, and enter the working mode after the self-checking is completed;

[0089] Multi-mode detection step: in response to the set timing instruction, the device is controlled to start the eccentric acoustic logging system or the active ultrasonic logging system to realize the acoustic or ultrasonic pulse transmission operation and the corresponding reflected wave or refracted wave signal reception operation in an alternating cycle, during which the device's azimuth information is obtained through the azimuth detection module, and the reflected wave or refracted wave signal and the azimuth signal during the operation are transmitted to the main control electronic compartment;

[0090] Acoustic information analysis steps: The main control electronic warehouse reads the full wave train waveform of the acoustic wave and the ultrasonic pulse wave train, and uses a multi-channel waveform similarity correlation algorithm to obtain the formation acoustic information of the formation outside the well and the formation near the well wall respectively. Combined with the azimuth information, radial tomography images and circumferential azimuth images of the sound velocity of the medium and long-distance formations, as well as circumferential azimuth images of the sound velocity of the formation near the well wall are formed.

[0091] The multi-scale acoustic imaging logging while drilling method provided by the embodiment of the present invention comprises configuring the acoustic imaging logging while drilling device of the present invention at the wellhead, setting the timing instructions for the logging work, and lowering the acoustic imaging logging while drilling device of the present invention into the wellbore filled with drilling fluid through the drilling tool assembly. The ground start-up instruction is transmitted to the acoustic imaging logging while drilling device of the present invention through the drilling fluid, and the acoustic imaging logging while drilling device of the present invention is started to perform self-checking. After the self-checking is successful, the acoustic imaging logging while drilling device of the present invention enters the logging while drilling working state according to the preset timing instructions.

[0092] Figure 4 The operating principle flow chart of the multi-scale acoustic imaging logging while drilling method of the present invention is shown, and the specific steps include:

[0093] Step 1: At a certain time t1, the polariton active transmitter 11 transmits an acoustic pulse in a direction toward the formation outside the well on one side of the non-magnetic drill collar 5 in the drilling fluid medium in the well. The acoustic pulse propagates along a certain direction of the formation outside the well and continuously refracts or reflects back into the drilling fluid in the well.

[0094] Step 2: The strip-type active receiver array 12 receives and collects the full wave train waveform of the sound wave refracted or reflected from a certain position of the formation outside the well in the drilling fluid in the well. The full wave train waveform of the sound wave only contains the information of a certain position of the formation outside the well related to the propagation path.

[0095] Step 3. Alternately, at the next moment t2 (t2-t1≥6ms), the upper and lower ultrasonic transmitting probes 21 and 22 simultaneously transmit ultrasonic pulse waves in the drilling fluid in the well to the near-wellbore wall formation on the other side of the drill collar. The ultrasonic pulse waves propagate in a certain direction of the near-wellbore wall formation and continuously refract back into the drilling fluid in the well.

[0096] Step 4: The ultrasonic receiver array 23 receives and collects the ultrasonic pulse wave train refracted from a certain position in the formation near the well wall in the drilling fluid in the well. The ultrasonic pulse wave train only contains information about a certain position area of ​​the formation near the well wall related to the propagation path.

[0097] Step 5: The main control electronic warehouse 4 reads the full acoustic wave train waveform and the ultrasonic pulse wave train, and uses a multi-channel waveform similarity correlation algorithm to obtain acoustic information such as the formation wave velocity and attenuation at a certain position of the formation outside the well and a certain position of the formation near the well wall.

[0098] Step 6: As the downhole drilling assembly rotates, repeat the above steps 1 to 5, and perform azimuth normalization processing according to the azimuth angle measured at each moment by the azimuth detection module 3, so as to obtain radial tomography images and circumferential azimuth images of the sound velocity of the medium and long-distance formations and circumferential azimuth images of the sound velocity of the near-wellbore formations.

[0099] The multi-scale acoustic imaging logging device used includes: drill collar, eccentric acoustic logging system, active transmitting and receiving ultrasonic logging system, azimuth detection module and main control electronic compartment;

[0100] The eccentric acoustic logging system and the active transmitting and receiving ultrasonic logging system are respectively arranged on the opposite outer sides of the drill collar in an embedded manner; the drill collar is a non-magnetic drill collar;

[0101] The eccentric acoustic logging acoustic system includes a polariton active transmitter, a strip-type active receiver array and a sound insulator structure, and is used to measure radial and circumferential acoustic characteristics of formations at medium and long distances from the wellbore wall in response to control instructions through eccentric directional transmission and reception modes;

[0102] The active transmitting and receiving ultrasonic logging acoustic system comprises an upper ultrasonic transmitting probe, a lower ultrasonic transmitting probe, an ultrasonic receiver array and an ultrasonic transmitting and collecting circuit, and is used to measure the circumferential acoustic characteristics of the formation near the well wall through the upper and lower transmitting and intermediate compensation receiving mode;

[0103] The azimuth detection module is nested on the outer wall of the drill collar and is used to determine the azimuth information of the rotation of the device at the real-time measurement moment;

[0104] The main control electronic compartment is nested and sealed inside the drill collar, and is respectively communicated with the eccentric acoustic logging system, the active transmitting and receiving ultrasonic logging system and the azimuth detection module to convey work instructions and obtain acoustic waveforms, ultrasonic waveforms and device azimuth information to form sound velocity imaging data of near-wellbore wall formations and medium- and long-distance formations.

[0105] Preferably, in one embodiment, the polariton active transmitter comprises an arc-shaped sheet-shaped transmitting transducer and a high-voltage excitation circuit, which is used to transmit an acoustic pulse signal in the drilling fluid in the well to the formation outside the well;

[0106] The strip-type active receiver array is on the same side as the polariton active transmitter but axially spaced a certain distance apart, and comprises a plurality of receiving transducers and an acoustic wave collection circuit, and is used to synchronously receive the full wave train waveform of the acoustic wave pulse returned from the formation outside the well in the drilling fluid in the well.

[0107] In an optional embodiment, the receiving transducers of the strip-type active receiver array are all rectangular plate-shaped receiving transducers, the sound wave collection circuit is arranged between two adjacent rectangular plate-shaped receiving transducers, and every two rectangular plate-shaped receiving transducers share one sound wave collection circuit.

[0108] Furthermore, in one embodiment, the sound insulator structure is disposed between the polariton active transmitter and the strip-type active receiver array to attenuate the direct wave signal of the acoustic wave propagating along the surface of the drill collar.

[0109] Specifically, in one embodiment, the sound insulation structure is formed by opening a plurality of periodic grooves or holes on the outer wall of the drill collar between the polariton active transmitter and the strip-type active receiver array, and applying vulcanized rubber thereon.

[0110] In a preferred embodiment, the upper ultrasonic transmitting and receiving probe and the lower ultrasonic transmitting probe of the active transmitting and receiving ultrasonic logging acoustic system are respectively located at the upper and lower parts of the active transmitting and receiving ultrasonic logging acoustic system, and the ultrasonic receiver array and the ultrasonic transmitting and collecting circuit are located in the middle part of the active transmitting and receiving ultrasonic logging acoustic system.

[0111] Furthermore, in one embodiment, the upper ultrasonic transmitting probe and the lower ultrasonic transmitting probe both use high-power ultrasonic cylindrical piezoelectric transducers;

[0112] The ultrasonic receiver array comprises a plurality of receiving probes arranged axially at equal intervals, and the receiving probes all adopt broadband high-sensitivity ultrasonic composite piezoelectric transducers.

[0113] Optionally, in one embodiment, the azimuth detection module includes a dual-axis magnetoresistive sensor and a detection circuit, which are nested on the outer wall of the drill collar on the same side as the active transceiver ultrasonic logging acoustic system, and collects magnetic tool face angle information to determine the azimuth information of the device rotation at the time of real-time measurement.

[0114] The technical solution of the embodiment of the present invention is suitable for fine evaluation of the circumferential heterogeneity and anisotropy of the formation from near the well wall to the middle and long distance under the condition of logging while drilling, and accurate detection of geological anomalies outside the well. On the one hand, the multi-scale acoustic imaging logging while drilling device provided adopts an ultrasonic logging acoustic system to measure the circumferential acoustic characteristics of the formation near the well wall; on the other hand, the multi-scale acoustic imaging logging while drilling device provided adopts an eccentric acoustic wave logging acoustic system to measure the radial and circumferential acoustic characteristics of the formation in the middle and long distance; the eccentric acoustic wave logging acoustic system can directionally emit acoustic wave pulses to a certain direction of the formation outside the well and receive the full wave train waveform of the acoustic wave reflected or refracted from the direction, and the active transmitting and receiving ultrasonic logging acoustic system can directionally emit ultrasonic pulses to another direction of the formation near the well wall and receive the ultrasonic pulse wave train refracted back from the direction. The main control electronic compartment reads the full acoustic wave train waveform, ultrasonic pulse wave train and measurement azimuth angle. Through processing and analysis, the circumferential azimuth imaging diagram of the near-wellbore wall formation sound velocity and the radial tomography imaging diagram and circumferential azimuth imaging diagram of the medium- and long-distance formation sound velocity can be obtained.

[0115] During detection, formation sound velocity imaging information extending from the near-wellbore formation to the mid-to-long distance formation can be effectively obtained in one logging while drilling process, reducing the impact of drilling fluid intrusion, and the measurement results can more truly reflect the characteristics of the original formation, with the advantages of large detection range, high measurement resolution, excellent imaging accuracy, rich measurement information, and more reliable measurement results. The multi-scale acoustic imaging logging while drilling device and method provided by the present invention can evaluate the circumferential heterogeneity and anisotropy of the near-wellbore formation and the formation outside the well, and identify geological anomalies such as the formation interface and cracks outside the well, which can significantly improve the benefits of exploration and development of unconventional oil and gas reservoirs.

[0116] For the above-mentioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the order of the actions described, because according to the present invention, some steps can be performed in other orders 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 required by the present invention.

[0117] It should be pointed out that in other embodiments of the present invention, the method can also obtain a new multi-scale acoustic imaging logging while drilling method by combining one or several of the above embodiments to achieve comprehensive and accurate detection of complex oil and gas formations.

[0118] It should be noted that, based on the method in any one or more of the above-mentioned embodiments of the present invention, the present invention also provides a storage medium, on which is stored a program code that can implement the method as described in any one or more of the above-mentioned embodiments, and when the code is executed by the operating system, it can implement the multi-scale acoustic imaging logging method while drilling as described above.

[0119] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0120] The "one embodiment" mentioned in the specification means that a particular feature, structure or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention. Therefore, the phrase "one embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0121] Although the embodiments disclosed in the present invention are as above, the above contents are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A multi-scale acoustic imaging logging device while drilling, characterized in that: The device comprises: a drill collar, an eccentric acoustic logging system, an active transmitting and receiving ultrasonic logging system, an azimuth detection module and a main control electronic compartment; The eccentric acoustic logging system and the active transmitting and receiving ultrasonic logging system are respectively arranged on the opposite outer sides of the drill collar in an embedded manner; the drill collar is a non-magnetic drill collar; The eccentric acoustic logging acoustic system includes a polariton active transmitter, a strip-type active receiver array and a sound insulator structure, and is used to measure radial and circumferential acoustic characteristics of formations at medium and long distances from the wellbore wall in response to control instructions through eccentric directional transmission and reception modes; The active transmitting and receiving ultrasonic logging acoustic system comprises an upper ultrasonic transmitting probe, a lower ultrasonic transmitting probe, an ultrasonic receiver array and an ultrasonic transmitting and collecting circuit, and is used to measure the circumferential acoustic characteristics of the formation near the well wall through the upper and lower transmitting and intermediate compensation receiving mode; The azimuth detection module is nested on the outer wall of the drill collar and is used to determine the azimuth information of the rotation of the device at the real-time measurement moment; The main control electronic compartment is nested and sealed inside the drill collar, and is respectively communicated with the eccentric acoustic logging system, the active transmitting and receiving ultrasonic logging system and the azimuth detection module to convey work instructions and obtain acoustic waveforms, ultrasonic waveforms and device azimuth information to form sound velocity imaging data of near-wellbore wall formations and medium- and long-distance formations.

2. The device according to claim 1, characterized in that The polariton active transmitter comprises an arc-shaped sheet-shaped transmitting transducer and a high-voltage excitation circuit, and is used to transmit an acoustic wave pulse signal in the drilling fluid in the well to the formation outside the well; The strip-type active receiver array is on the same side as the polariton active transmitter but axially spaced a certain distance apart, and comprises a plurality of receiving transducers and an acoustic wave collection circuit, and is used to synchronously receive the full wave train waveform of the acoustic wave pulse returned from the formation outside the well in the drilling fluid in the well.

3. The device according to claim 1, characterized in that The receiving transducers of the strip-type active receiver array are all rectangular plate-shaped receiving transducers, the sound wave collection circuit is arranged between two adjacent rectangular plate-shaped receiving transducers, and every two rectangular plate-shaped receiving transducers share one sound wave collection circuit.

4. The device according to claim 1, characterized in that The sound insulation structure is formed by opening a plurality of periodic grooves or holes on the outer wall of the drill collar between the polariton active transmitter and the strip-type active receiver array, and coating the outer wall with vulcanized rubber.

5. The device according to claim 1, characterized in that The upper ultrasonic transmitting and detecting probe and the lower ultrasonic transmitting probe of the active transmitting and receiving ultrasonic logging acoustic system are respectively located at the upper part and the lower part of the active transmitting and receiving ultrasonic logging acoustic system, and the ultrasonic receiver array and the ultrasonic transmitting and collecting circuit are located in the middle part of the active transmitting and receiving ultrasonic logging acoustic system.

6. The device according to claim 1, characterized in that The upper ultrasonic transmitting probe and the lower ultrasonic transmitting probe both adopt high-power ultrasonic cylindrical piezoelectric transducers; The ultrasonic receiver array comprises a plurality of receiving probes arranged axially at equal intervals, and the receiving probes all adopt broadband high-sensitivity ultrasonic composite piezoelectric transducers.

7. The device according to claim 1, characterized in that The azimuth detection module includes a dual-axis magnetoresistive sensor and a detection circuit, which are nested on the outer wall of the drill collar on the same side as the active ultrasonic logging acoustic system, and collects magnetic tool face angle information to determine the azimuth information of the device rotation at the real-time measurement moment.

8. A multi-scale acoustic imaging logging while drilling method, characterized in that: The method is applied to the device according to any one of claims 1 to 7, and the method comprises: Startup and self-checking steps: lower the configured multi-scale acoustic imaging logging device while drilling into a wellbore filled with drilling fluid, automatically execute the self-checking program after starting in response to the ground start command, and enter the working mode after the self-checking is completed; Multi-mode detection step: in response to the set timing instruction, the device is controlled to start the eccentric acoustic logging system or the active ultrasonic logging system in the set drilling azimuth to realize the acoustic wave or ultrasonic pulse transmission operation and the corresponding reflected wave or refracted wave signal reception operation, and the azimuth information of the device is obtained through the azimuth detection module during the operation, and the reflected wave or refracted wave signal and the azimuth signal during the operation are transmitted to the main control electronic compartment; Acoustic information analysis steps: The main control electronic warehouse reads the full wave train waveform of the acoustic wave and the ultrasonic pulse wave train, and uses a multi-channel waveform similarity correlation algorithm to obtain the formation acoustic information of the formation outside the well and the formation near the well wall respectively. Combined with the azimuth information, radial tomography images and circumferential azimuth images of the sound velocity of the medium and long-distance formations, as well as circumferential azimuth images of the sound velocity of the formation near the well wall are formed.

9. The method according to claim 8, characterized in that In the multi-mode detection step, at a certain moment, the polariton active transmitter transmits an acoustic wave pulse in a direction toward the formation outside the well on one side of the drill collar in the drilling fluid medium in the well, and the acoustic wave pulse propagates along a certain direction of the formation outside the well and continuously refracts or reflects back into the drilling fluid in the well; At the next moment, the upper and lower ultrasonic transmitting probes simultaneously transmit ultrasonic pulse waves in the drilling fluid in the well to the near-wellbore wall formation on the other side of the drill collar. The ultrasonic pulse waves propagate in a certain direction of the near-wellbore wall formation and continuously refract back into the drilling fluid in the well.

10. A storage medium, characterized in that: The storage medium stores program code that is expected to implement the method as claimed in any one of claims 1 to 7.

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