Microseism monitoring system

Abstract

The embodiment of the invention relates to the field of earthquake detection, in particular to a micro-earthquake monitoring system. The system is suitable for monitoring a high-level waste disposal underground laboratory, and comprises a plurality of ground surface monitors arranged on the ground surface of the underground laboratory and used for monitoring micro-earthquakes of an underground shallow layer; a plurality of in-well monitors disposed in a peripheral well of the underground laboratory and disposed to monitor microseisms in the underground deep layer; the processor is arranged to receive data from the ground surface monitor and the in-well monitor respectively and determine the stability of the surrounding stratum of the underground laboratory based on the data, and the ground surface monitor and the in-well monitor are arranged at preset positions respectively so that the data provided by the ground surface monitor and the in-well monitor can improve the accuracy of determining the stability. A plurality of micro-seismic monitors are arranged on the earth surface and in a well at the same time, micro-seismic fluctuation of an underground shallow layer and a deep rock stratum is accurately recorded, the stability of the stratum is comprehensively monitored, and micro-seismic monitoring in a three-dimensional space is achieved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of earthquake detection, and in particular to a microseismic monitoring system. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] Microseismic waves are weaker seismic waves generated during deep mining in underground mines. Microseismic waves can cause rock fractures and sliding, which in turn cause displacement of rock formations inside the mine. This displacement can damage the support structure, causing the mine to lose stability and lead to production safety accidents. Summary of the invention

[0004] A brief overview of the present application is provided below in order to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify the key or important parts of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0005] An embodiment of the present application provides a microseismic monitoring system, which is suitable for monitoring an underground laboratory for high-level radioactive waste disposal, and includes: a plurality of surface monitors, which are arranged on the surface of the underground laboratory and are configured to monitor microseismicity of shallow underground layers; a plurality of well monitors, which are arranged in wells around the underground laboratory and are configured to monitor microseismicity of deep underground layers; and a processor, which is configured to receive data from the surface monitors and the well monitors, respectively, and determine the stability of the surrounding strata of the underground laboratory based on the data, wherein the surface monitors and the well monitors are respectively arranged at predetermined positions so that the data provided by them can improve the accuracy of determining stability.

[0006] The microseismic monitoring system provided in the embodiments of the present application can accurately record the microseismic fluctuations of shallow and deep underground rock formations by simultaneously setting up multiple monitors for detecting microseisms on the surface and in the well. It can comprehensively monitor the stability of the formations around the underground laboratory and realize microseismic monitoring in three-dimensional space. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to further illustrate the above and other advantages and features of the present application, the specific embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. The accompanying drawings together with the following detailed description are included in this specification and form a part of this specification. Elements with the same function and structure are represented by the same reference numerals. It should be understood that these drawings only describe typical examples of the present application and should not be regarded as limiting the scope of the present application.

[0008] Figure 1 is a schematic diagram of the overall structure of a microseismic monitoring system provided in an embodiment of the present application; Figure 2 It is a schematic diagram of the horizontal layout of the microseismic monitoring system provided in the embodiment of the present application; Figure 3 It is a schematic diagram of the well deployment method of the microseismic monitoring system provided in the embodiment of the present application; Figure 4 It is a partial structural diagram of an optical data transmission network provided in an embodiment of the present application; Figure 5 It is a partial structural diagram of a central data acquisition, processing and analysis unit provided in an embodiment of the present application; Figure 6 It is a partial structural schematic diagram of a solar power supply device provided in an embodiment of the present application; Figure 7 It is a schematic diagram of determining the positions of a surface monitor and an underground monitor provided in an embodiment of the present application.

[0009] Description of reference numerals: 100. Microseismic monitoring system; 10. Surface monitor; 101. Surface monitor data line; 20. Well; 201. Well monitor; 202. Well monitor data line; 3. Optical fiber data transmission network; 31. Photoelectric converter; 4. Central data acquisition, processing and analysis unit; 40. Total data line; 41. Data switch; 42. Processor; 5. Solar power supply device; 51. Solar panel; 52. Solar power transmission controller; 53. Battery; 501. Monitor power line; 60. Monitoring point; 61. Seismic source; 62. Interface; 63. Intersection. DETAILED DESCRIPTION

[0010] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0011] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0012] The disclosure below provides a plurality of different embodiments or examples to implement the present application. In order to simplify the disclosure of the present application, the parts and methods of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the present application. In the description of the embodiments of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically limited.

[0013] Generally speaking, microseismic monitoring technology monitors and analyzes real-time microseismic data by setting up monitors in the source area to monitor and locate the rupture or movement of underground rock masses, thereby understanding the stability of the strata around the mine. Microseismic monitoring technology is usually divided into two types: well monitoring and ground monitoring. Among them, the monitors for ground monitoring are directly affected by the surrounding environment because they are set on the surface, and the noise brought by the surface environment will affect the signal quality. Well monitoring often uses adjacent well monitoring, which has a high data signal-to-noise ratio and event positioning accuracy, but is easily limited by observation wells. If there is no well with a suitable distance and depth around the fracturing well as an observation well, it is impossible to carry out adjacent well monitoring, and due to the small observation aperture, the horizontal positioning accuracy is affected by the observation distance. Therefore, there are still technical difficulties in achieving full-scale monitoring of microseisms in space.

[0014] The embodiment of the present application provides a microseismic monitoring system, which is suitable for monitoring underground laboratories for high-level radioactive waste disposal. Figure 1 The overall structure diagram of the microseismic monitoring system provided by the embodiment of the present application is shown. Figure 3 A schematic diagram showing the layout of a microseismic monitoring system in a well provided by an embodiment of the present application is shown. In some embodiments, for example, Figure 1 and Figure 3 As shown, it includes: a plurality of surface monitors 10, the surface monitors 10 are arranged on the surface of the underground laboratory, and are configured to monitor microseismicity of shallow underground layers; a plurality of well monitors 201, the well monitors 201 are arranged in wells 20 around the underground laboratory, and are configured to monitor microseismicity of deep underground layers; a processor 42, the processor 42 is configured to receive data from the surface monitors 10 and the well monitors 201, respectively, and determine the stability of the surrounding formations of the underground laboratory based on the data, wherein the surface monitors 10 and the well monitors 201 are respectively arranged at predetermined positions so that the data provided by them can improve the accuracy of determining stability.

[0015] The microseismic monitoring system provided in the embodiments of the present application can accurately record the microseismic fluctuations of shallow and deep underground rock formations by simultaneously setting up multiple monitors for detecting microseisms on the surface and in the well. It can comprehensively monitor the stability of the formations around the underground laboratory and realize microseismic monitoring in three-dimensional space.

[0016] In some embodiments, the predetermined positions of the plurality of surface monitors 10 and the plurality of well monitors 201 are set to minimize the length of the connection between the plurality of surface monitors 10 and the plurality of well monitors 201. The setting method here can improve the accuracy and stability of microseismic fluctuation monitoring.

[0017] In some embodiments, the plurality of surface monitors 10 are connected in a line to form a quadrilateral.

[0018] In some embodiments, the distance between every two surface monitors 10 is set to be between 633 meters and 1273 meters.

[0019] When selecting a deployment area, an area with relatively stable geological conditions and away from faults should be selected to prevent violent stratum movement from causing damage to the well 20 and the microseismic monitoring system 100.

[0020] In some embodiments, in order to cover the entire underground laboratory, the distribution of the ground facilities to be built and the azimuth distribution of the monitor array formed by the well monitor 201 should be considered. The well array is arranged in multiple wells 20 respectively, and the well monitor 201 can be set as a 4-level three-component detector.

[0021] Figure 7 A schematic diagram showing the positions of the surface monitor and the well monitor provided by an embodiment of the present application is shown, which is determined by tracing the path of the seismic wave ray. Figure 7 In the illustrated embodiment, the monitor is arranged at the monitoring point, that is, the position of the monitoring point represents the position of the monitor. The following mainly describes the determination of the position of the monitoring point. Figure 7 As shown, there are n layers of interfaces 62 between the earthquake source 61 and the monitoring point 60. The rays emitted by the earthquake source 61 have n intersection points 63 with the interface 62. The coordinates of the i-th intersection point 63 are ( ), set the following expression to represent interface 62: , ( ) represents the interface 62, and the coordinates of the earthquake source 61 are expressed as ( ), the coordinates of monitoring point 60 are ( ), there are n+1 line segments connecting the earthquake source 61, the monitoring point 60 and the intersection point 63, and their lengths are respectively set to , the total travel time t is:

[0022] The position of the monitoring point 60 is set to minimize the value of t, v i Represents the velocity of longitudinal waves.

[0023] According to the above expression, when t is the smallest, it indicates that the microseismic monitoring system composed of all monitors receives the microseismic waves from the source in the shortest time, and the arrangement of the monitors that meets this situation is the arrangement adopted in this embodiment. That is, using the above expression, when t is the smallest, it can be solved to determine the position of the monitoring point 60, and also the position of each monitor (including the surface monitor 10 and the in-well monitor 201) can be determined.

[0024] The surface monitor 10 and the in-hole monitor 201 are arranged in the above manner, which improves the accuracy and stability of microseismic fluctuation monitoring and can also improve its response speed, thereby making a rapid response to earthquake events.

[0025] In some embodiments, Figure 3 As shown, the arrangement of the plurality of well monitors 201 in the well 20 is such that a predetermined distance exists between two well monitors 201 along the vertical extension direction of the well 20 .

[0026] In some embodiments, the number of wells 20 can be set to 3, and the same number of well monitors 201 can be set in each well 20, wherein the number of well monitors 201 and the distance between two adjacent well monitors 201 are determined according to the depth of the well 20.

[0027] In some embodiments, Figure 3 As shown, four well monitors 201 can be arranged in each well 20, and each well monitor 201 is adjacent to the same first predetermined distance, and the distance between the well monitor 201 closest to the wellhead and the wellhead is the second predetermined distance, and the first predetermined distance is greater than the second predetermined distance.

[0028] In some embodiments, the depth of the well 20 is 575 meters, and four well monitors 201 are installed in the well 20, so that the spacing between the installed well monitors 201 is 150 meters, and the well monitor 201 closest to the bottom of the well is 350 meters away from the wellhead. The first predetermined distance is set to be greater than the second predetermined distance to ensure that the density of the well monitors 201 near the bottom of the well 20 is within a suitable range, and the second predetermined distance is given priority to ensure that the deep microseismic data can be collected, while the range of the first predetermined distance can be covered by the surface monitor 10, so that the coverage range of the surface monitor 10 and the well monitor 201 in the depth direction is complementary to each other, and omissions in the monitoring of seismic waves are prevented.

[0029] Figure 2FIG. 1 shows a schematic diagram of a horizontal arrangement of a microseismic monitoring system provided by an embodiment of the present application. In some embodiments, for example, Figure 2 As shown, four surface monitors are arranged on the surface, and three wells 20 are arranged, and a number of well monitors 201 are arranged in each well 20, wherein the four surface monitors 10 and the three wells 20 are arranged so that the lines connecting the three surface monitors 10 and the three wells 20 form a circle, and one surface monitor 10 outside the three surface monitors 10 is located at the center of the circle.

[0030] In some embodiments, three surface monitors 10 and three wells 20 located on the circumference are arranged at intervals from each other, and the angle between the lines connecting adjacent surface monitors 10 or wells 20 located on the circumference and the surface monitor 10 located at the center of the circle is 60°±10°.

[0031] By arranging the surface monitors 10 and the wells 20 at intervals, the surface monitors 10 on the horizontal plane are evenly distributed, and the seismic waves on the shallow surface are evenly covered and monitored.

[0032] In the above embodiments, the inventors have provided a variety of arrangements of the surface monitors 10 and the well monitors 201, which can be used in combination or independently. By arranging the surface monitors 10 and the well monitors 201 in association, the monitoring advantages of the surface monitors 10 and the well monitors 201 can be obtained simultaneously, and the monitoring effect cannot be achieved by monitoring on the surface alone or monitoring in the well alone. In particular, the inventors of the present invention have proposed an arrangement of the surface monitors 10 and the well monitors 201 that cooperate with each other, so that the microseismic fluctuations of the shallow and deep underground rock formations can be accurately recorded, the stability of the formations around the underground laboratory can be fully monitored, and microseismic monitoring in three-dimensional space can be realized.

[0033] Figure 6 A partial structural schematic diagram of a solar power supply device provided in an embodiment of the present application is shown. In some embodiments, for example Figure 6 As shown, a solar power supply device 5 may also be provided, and the solar power supply device 5 is configured to supply power to the surface monitor 10 and the in-well monitor 201 .

[0034] In some embodiments, the solar power supply device 5 includes a solar panel 51, a solar power transmission controller 52, a battery 53 and a monitor power supply line 501. The solar panel 51 obtains solar energy and converts it into electrical energy, which is then controlled by the solar power transmission controller 52 to be transmitted into the battery 53. The battery 53, as an energy storage device, can ensure that the monitor can be constantly powered through the monitor power supply line 501 when there is a lack of solar energy supply in rainy weather or at night, thereby getting rid of the limitations of external power supply conditions and ensuring the long-term stable operation of the microseismic monitoring system 100.

[0035] In some embodiments, the in-well monitor 201 is installed in a coupled manner that is movable and thus easy to maintain. The monitor can be installed in a spherical distribution manner, which can achieve higher earthquake source positioning accuracy.

[0036] Figure 4 A partial structural diagram of an optical data transmission network provided in an embodiment of the present application is shown. Figure 5 The partial structural diagram of the central data acquisition, processing and analysis unit provided in the embodiment of the present application is shown. In some embodiments, Figure 1 and Figure 4 As shown, the shallow surface data collected by the surface monitor 10 is transmitted to the photoelectric converter 31 through the surface monitor data line 101, and the deep data collected by the well monitor 201 is transmitted to the photoelectric converter 31 through the well monitor data line 202. The photoelectric converter 31 converts the obtained microseismic digital signal into an optical signal, transmits it to the next-stage photoelectric converter 31 through the armored optical fiber, and converts the optical signal into an electrical signal. In some embodiments, as Figure 1 and Figure 5 As shown, the electrical signal output by the photoelectric converter 31 is input to the data switch 41 through the surface monitor data line 101 and the well monitor data line 202, and is transmitted to the processor 42 through the main data line 40. The processor 42 analyzes the spatial and temporal information of the microseismic event to determine the stability of the formation around the underground laboratory.

[0037] In some embodiments, optical sensors can also be placed near the monitor to obtain physical quantities such as temperature and pressure in real time to provide more comprehensive data support for earthquake monitoring. Setting up an additional optical fiber network can ensure that when a part of the data transmission line fails, the data can still be transmitted stably, thereby improving the reliability and stability of the microseismic monitoring system 100.

[0038] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0039] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A microseismic monitoring system, which is suitable for monitoring underground laboratories for high-level radioactive waste disposal, characterized in that: It includes: A plurality of surface monitors, each of which is disposed on the surface of the underground laboratory and configured to monitor microseismic activity in a shallow underground layer. A plurality of well monitors, which are arranged in wells around the underground laboratory and are configured to monitor microseismic activity in deep underground layers. A processor configured to receive data from the surface monitor and the in-well monitor, respectively, and determine the stability of the surrounding formation of the underground laboratory based on the data, wherein: The surface monitor and the in-hole monitor are respectively arranged at predetermined positions so that the data provided by them can improve the accuracy of determining the stability.

2. The system according to claim 1, characterized in that The predetermined positions where the plurality of surface monitors and the plurality of in-well monitors are arranged are set to make the length of the connection lines between the plurality of surface monitors and the plurality of in-well monitors as short as possible.

3. The system according to claim 1, characterized in that The connection lines of the plurality of ground surface monitors are arranged to form a quadrilateral.

4. The system according to claim 1, characterized in that The plurality of well monitors are arranged in the well in such a manner that a predetermined distance exists between two well monitors along a vertical extension direction of the well.

5. The system according to claim 2, characterized in that There are n layers of interfaces between the earthquake source and the monitoring point. The rays emitted by the earthquake source have n intersections with the interface. The coordinates of the i-th intersection are ( ), set the following expression to represent the interface: , ( ) represents the interface, The coordinates of the earthquake source are expressed as ( ), The coordinates of the monitoring point are ( ), there are n+1 line segments connecting the earthquake source, the monitoring point and the intersection, and their lengths are respectively set to , the total travel time t is: The position of the monitoring point is set to minimize the value of t, v i Represents the velocity of longitudinal waves.

6. The system according to claim 1, characterized in that Four surface monitors are arranged on the surface, and three wells are arranged, and a number of well monitors are arranged in each well. The four surface monitors and the three wells are arranged so that the lines connecting the three surface monitors and the three wells form a circle, and one surface monitor other than the three surface monitors is located at the center of the circle.

7. The system according to claim 6, characterized in that The three surface monitors and the three wells located on the circumference are arranged at intervals from each other, and the angle between the lines connecting the adjacent surface monitors or wells located on the circumference and the surface monitor located at the center of the circle is 60°±10°.

8. The system according to claim 7, characterized in that , Four well monitors are arranged in each of the wells, each well monitor is adjacent to the other by the same first predetermined distance, and the distance between the well monitor closest to the wellhead and the wellhead is a second predetermined distance, The first predetermined distance is greater than the second predetermined distance.

9. The system according to claim 3, characterized in that The distance between each two surface monitors is set between 633 meters and 1273 meters.

10. The system according to any one of claims 1 to 9, characterized in that: It also includes a solar power supply device, which is configured to supply power to the surface monitor and the in-well monitor.

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