An integrated electric shock monitoring method and device based on electronically controlled trace explosives

Abstract

The present invention belongs to the technical field of oilfield and hot dry rock development, and discloses an integrated electro-seismic monitoring method and device based on electrically controlled trace explosives. The method comprises the following steps: arranging an array observation system on the ground in the drilling and fracturing section; supplying power to the wellbore to control the explosion of the trace explosives; transmitting the electromagnetic signal received by the electromagnetic sensor and the vibration signal received by the detector to a receiving system via a communication cable; calculating the position of the vibration signal using a source location algorithm, and calculating the position of the electromagnetic signal using a field source location algorithm to obtain the position of the proppant and the range of the fracturing fluid; and evaluating the fracturing effect based on the calculated position results. By supplying a human-safe voltage to the wellbore to excite the trace explosives, the trace explosives explode after receiving the emitted electromagnetic signal, acting as a source to emit a vibration signal, thereby facilitating surface observation, and the monitoring results directly indicating the position of the proppant.

Description

Technical Field

[0001] The invention belongs to the technical field of oil field and hot dry rock development, and particularly relates to an electric-seismic integrated monitoring method and device based on electronically controlled trace explosives. Background Art

[0002] Among current hydraulic pressure monitoring technologies, microseismic and electromagnetic methods are the most common. The physical mechanism of microseismic methods is clear, and they can identify rock fractures, but they cannot determine the extent of liquid impact or identify effectively propped fractures. The physical mechanism of electromagnetic methods is also clear, and they can identify the extent of liquid impact, but they cannot identify the extension patterns of fracture networks or accurately determine effectively propped fractures. The key reason why both microseismic and electromagnetic methods cannot identify effectively propped fractures is the difficulty in monitoring proppants. Microseismic monitoring involves microseismic events caused by changes in the stress field during fracturing. Liquid may not necessarily reach the location of the event, and proppant may not necessarily reach the location of the liquid. Therefore, the microseismic reconstruction volume is much larger than the effective proppant volume. Electromagnetic methods have difficulty identifying low proppant concentrations.

[0003] To address these issues, patent publication number CN113625367A, "An Integrated Electroseismic Monitoring Method and System Based on Electrostrictive Materials," introduces a monitoring method based on electrostrictive materials. This method combines the advantages of electrical signal frequency characteristics with the advantages of microseismic event location, developing the passive seismic source of traditional microseismic monitoring methods into a controllable artificial seismic source signal, capable of accurately identifying effective propped fractures. By stimulating proppants with different frequency characteristics to vibrate with electrical signals, the effectiveness of repeated stimulation can be evaluated. Furthermore, conductive proppants with different frequency characteristics can be injected into different fractured layers within the same well, and by supplying multi-frequency current signals, simultaneous monitoring of multiple layers can be achieved.

[0004] However, it does not propose a practical direct proppant monitoring technology. Microseismic technology can infer proppant location by monitoring fracture locations, but it is an indirect monitoring technology with a weak signal. Furthermore, electrical and electromagnetic methods monitor the range of low-resistivity fracturing fluids but cannot indicate the specific fracture and proppant locations. Downhole or surface inclination monitoring is also indirect monitoring with low accuracy. Summary of the Invention

[0005] The purpose of the present invention is to provide an integrated electric shock monitoring method and device based on electronically controlled trace explosives to solve the problems in the prior art raised in the above background technology.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] An integrated electro-seismic monitoring method based on electrically controlled trace explosives comprises the following steps: S1, arranging an array observation system on the ground of a drilling fracturing section, comprising an electromagnetic sensor, a geophone, a communication cable and a receiving system, and ensuring that the observation system is in normal working condition; S2, supplying power to the wellbore to control the explosion of the trace explosive; S3, transmitting the electromagnetic signal received by the electromagnetic sensor and the vibration signal received by the geophone to the receiving system via the communication cable; S4, calculating the position of the vibration signal using a source location algorithm, calculating the position of the electromagnetic signal using a field source location algorithm, and obtaining the position of the proppant and the range of the fracturing fluid; and S5, evaluating the fracturing effect based on the calculated position results.

[0008] The trace explosives are mixed with proppant and introduced into the fractured layer. Multiple sets of electromagnetic sensors and detectors are provided, each irregularly buried in the ground surrounding the fractured well site. The electromagnetic and vibration signals are generated by supplying a human-safe voltage to the wellbore, triggering the explosion of the trace explosives.

[0009] The steps for deploying the array observation system are as follows: Dig pits around the well site to bury the electromagnetic sensors and detectors; Place the electromagnetic sensors and detectors in the pits and compact them with soil; Connect the electromagnetic sensors and detectors to the receiving system via communication cables and power it up. The receiving system is a computer equipped with a field source location algorithm.

[0010] In another aspect, the present invention provides an integrated electric seismic monitoring device based on electronically controlled trace explosives, comprising: a receiving system; an electromagnetic sensor and a detector connected to the receiving system; and a power supply for providing power to the receiving system, the electromagnetic sensor, and the detector. A signal generator system is provided; the signal generator system is configured to generate electromagnetic and seismic signals for reception by the electromagnetic sensor and the detector.

[0011] The signal source generating system includes: a micro-explosive package, which is placed in the fractured layer with a proppant; and an electrode connected to the micro-explosive package, which is used to discharge and trigger the micro-explosive package to explode. The voltage used by the electrode is lower than the safety voltage for the human body.

[0012] Technical effects and advantages of the present invention: The electric shock integrated monitoring method and device based on electronically controlled trace explosives proposed in the present invention has the following advantages over the prior art:

[0013] 1. The present invention supplies a human body safe voltage to the wellbore to excite a trace explosive. The trace explosive can explode after receiving the emitted electromagnetic signal, and emit a vibration signal as a seismic source, which is easy to observe on the surface. The monitoring results directly indicate the position of the proppant, which has the advantages of high safety, low cost, simple operation and high precision. The electromagnetic signal generated by the safe voltage in the fracturing layer can be combined to comprehensively evaluate the fracturing effect.

[0014] 2. Trace explosives emit stronger vibration signals, facilitating ground observation. Trace explosives are not proppants, but are mixed with proppants before entering the formation. They have the same distribution as proppants in the fracturing layer, so monitoring the position of the trace explosives can reveal the position of the proppants. Arranging sensors in an irregular grid reduces construction steps and adapts to different terrains. It can be used for fracturing monitoring of vertical and horizontal wells in hot dry rocks and unconventional oil and gas fields.

[0015] 3. Continuous monitoring can be performed by controlling different explosion times. At the same time, the low-resistance signal of the fracturing fluid can be used to monitor the scope of the fracturing fluid, thereby comprehensively analyzing the fracturing effect and obtaining the locations of cracks and fracturing fluid at the same time. This provides rich information and is more conducive to analyzing the fracturing effect.

[0016] 4. Irregular grid layout of sensors and detectors reduces construction steps and adapts to different terrains. It can be used for fracturing monitoring of vertical and horizontal wells in hot dry rocks and unconventional oil and gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a flow chart of an electric shock integrated monitoring method based on electronically controlled trace explosives according to the present invention;

[0018] Figure 2 Flowchart for arranging the array observation system of the present invention;

[0019] Figure 3 This is a structural diagram of a monitoring device arranged in a vertical well in an embodiment of the present invention;

[0020] Figure 4 This is a structural diagram of a monitoring device arranged in a horizontal well in an embodiment of the present invention.

[0021] In the figure: 1. Electromagnetic sensor; 2. Detector; 3. Power supply. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] Example 1

[0024] The present invention provides an embodiment of the Figure 1 The electric shock integrated monitoring method based on electronically controlled trace explosives shown includes the following steps:

[0025] S1. Arrange an array observation system on the ground at the drilling and fracturing section, including electromagnetic sensors 1, geophones 2, communication cables, and a receiving system. Multiple groups of electromagnetic sensors 1 and geophones 2 are provided. Multiple groups of electromagnetic sensors 1 and geophones 2 are irregularly buried on the ground around the well site of the fracturing well, and the observation system is kept in normal working condition.

[0026] like Figure 2 As shown, when arranging the array observation system, the steps are as follows:

[0027] S1.1. Dig a pit on the ground around the well site for burying the electromagnetic sensor 1 and the detector 2;

[0028] S1.2. Place the electromagnetic sensor 1 and detector 2 in the pit and tamp them with soil;

[0029] S1.3. Connect the electromagnetic sensor 1 and the detector 2 to the receiving system via a communication cable, and turn on the power supply 3.

[0030] S2. Power is supplied to the wellbore to control the explosion of the trace explosives, which are mixed with the proppant and enter the fracturing layer together.

[0031] S3. Send the electromagnetic signal received by the electromagnetic sensor 1 and the vibration signal received by the detector 2 to the receiving system through the communication cable; the electromagnetic signal and the vibration signal are generated by supplying a human body safety voltage to the wellbore to stimulate the explosion of trace explosives.

[0032] S4. Calculate the location of the vibration signal using a source location algorithm, calculate the location of the electromagnetic signal using a field source location algorithm, and obtain the location of the proppant and the range of the fracturing fluid;

[0033] S5. Evaluate the fracturing effect based on the calculated position results.

[0034] By supplying human-safe voltage to the wellbore to excite trace explosives, the trace explosives can explode after receiving the emitted electromagnetic signals, and send vibration signals as a seismic source, making it easy to observe on the surface, and the monitoring results directly indicate the position of the proppant. It has the advantages of high safety, low cost, simple operation and high precision. In combination with the electromagnetic signal generated by the safe voltage in the fracturing layer, the fracturing effect is comprehensively evaluated.

[0035] Example 2

[0036] This embodiment proposes an electric shock integrated monitoring device based on electronically controlled trace explosives, such as Figure 3 and Figure 4 As shown. Among them, Figure 3 The figure shows the state where the monitoring device is arranged in a vertical well; Figure 4 The diagram shows the state where the monitoring device is arranged in a horizontal well.

[0037] Specifically, it includes: a receiving system; an electromagnetic sensor 1 and a detector 2 connected to the receiving system; and a power supply 3 for providing power to the receiving system, the electromagnetic sensor 1, and the detector 2. A signal source generating system; the signal source generating system is used to generate electromagnetic signals and vibration signals for reception by the electromagnetic sensor 1 and the detector 2.

[0038] Trace explosives emit stronger vibration signals, which facilitates observation on the ground. Trace explosives are not proppants, but are mixed with proppants before entering the formation. They have the same distribution as proppants in the fracturing layer, so monitoring the position of the trace explosives can reveal the position of the proppants. Sensors are arranged in irregular grids to reduce construction steps and adapt to different terrains. They can be used for fracturing monitoring of vertical and horizontal wells in hot dry rocks and unconventional oil and gas.

[0039] In some embodiments, the signal source generating system includes: a micro-explosive package, the micro-explosive package and a proppant placed in the fractured layer; and an electrode connected to the micro-explosive package, the electrode configured to discharge and trigger the micro-explosive package to explode. The voltage used by the electrode is lower than a safety voltage for the human body.

[0040] Specifically, continuous monitoring can be achieved by controlling the timing of different explosions. Simultaneously, the low-resistance signal of the fracturing fluid can be used to monitor the fluid's reach, enabling a comprehensive analysis of the fracturing effect. The locations of both the cracks and the fracturing fluid are simultaneously determined, providing rich information that facilitates analysis of fracturing effectiveness. The irregular grid layout of sensors and geophones reduces construction steps and adapts to varying terrains. It can be used for fracturing monitoring in vertical and horizontal wells in hot dry rock and unconventional oil and gas production.

[0041] As an optional implementation, it also includes a single-chip microcomputer, which communicates with the computer using serial communication. Serial communication is a communication method that transmits data bit by bit through data signal lines, ground lines, control lines, etc. Serial communication represented by RS232 protocol uses a data communication program written in VB as an intermediary to transmit data between Kingview and the single-chip microcomputer. Dynamic data exchange DDE is used to facilitate real-time data exchange. The feedback signals of the electromagnetic sensor 1 and the detector 2 are calculated through formulas to realize online measurement data on the display computer.

[0042] Furthermore, the receiving system is a computer equipped with a field source positioning algorithm, which is provided with a memory and a processor, the memory stores a computer program, and the processor is configured to run the computer program to execute the method in the above embodiment.

[0043] The above program can be run in a processor or stored in a memory (or computer-readable medium), which includes permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media such as modulated data signals and carrier waves.

[0044] These computer programs can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps of the functions specified in one or more blocks can be implemented by different modules corresponding to different steps.

[0045] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An integrated electric shock monitoring method based on electronically controlled trace explosives, characterized in that: The steps include: S1. Arrange an array observation system on the surface of the drilling and fracturing section, including electromagnetic sensors, geophones, communication cables, and a receiving system, and ensure that the observation system is in normal working condition; S2, supplying power to the wellbore to control the explosion of trace explosives; S3, sending the electromagnetic signal received by the electromagnetic sensor and the vibration signal received by the detector to the receiving system through the communication cable; S4. Calculate the location of the vibration signal using a source location algorithm, calculate the location of the electromagnetic signal using a field source location algorithm, and obtain the location of the proppant and the range of the fracturing fluid; S5. Evaluate the fracturing effect based on the calculated position results.

2. The electric shock integrated monitoring method based on electronically controlled trace explosives according to claim 1, characterized in that: The trace explosive is mixed with the proppant and enters the fracture layer together.

3. The electric shock integrated monitoring method based on electronically controlled trace explosives according to claim 1, characterized in that: The electromagnetic sensors and detectors are provided in several groups; Furthermore, several groups of electromagnetic sensors and detectors are buried in irregular shapes on the ground around the well site of the fracturing well.

4. The electric shock integrated monitoring method based on electronically controlled trace explosives according to claim 1, characterized in that: The electromagnetic signal and the vibration signal are generated by supplying a human body-safe voltage to the wellbore to stimulate the explosion of a trace amount of explosives.

5. The electric shock integrated monitoring method based on electronically controlled trace explosives according to claim 1, characterized in that: When arranging an array observation system, the steps are as follows: S1.

1. Dig pits on the ground around the well site for burying electromagnetic sensors and detectors; S1.

2. Place the electromagnetic sensor and detector in the pit and tamp it with soil; S1.

3. Connect the electromagnetic sensor and detector to the receiving system via a communication cable and turn on the power.

6. The electric shock integrated monitoring method based on electronically controlled trace explosives according to claim 5, characterized in that: The receiving system is a computer equipped with a field source positioning algorithm.

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