CN211402765U - Optical fiber acoustic sensing well-ground seismic data combined mining system - Google Patents

Abstract

The utility model discloses a combined acquisition system for well-ground seismic data based on distributed optical fiber acoustic wave sensing, in order to solve the energy inconsistency caused by repeated excitation of each source point when well and ground seismic data are collected separately in the prior art, The frequency spectrum is inconsistent, and the coupling between the source and the ground is not completely consistent; the utility model is based on the well-ground seismic data joint stereo acquisition system composed of the distributed optical fiber acoustic wave sensing seismic data acquisition unit and the ground seismic data acquisition unit in the well, and the Well-ground combined three-dimensional exploration and synchronous acquisition of ground and well seismic data to achieve high-density, high-efficiency, high-resolution, and low-cost well-ground combined three-dimensional seismic exploration technology for oil and gas resource exploration and comprehensive evaluation.

Description

Optical Fiber Acoustic Sensing Combined Mining System for Well Earth Seismic Data

technical field

The utility model belongs to the fields of application geophysics, geophysical exploration technology and seismic exploration, in particular to a well-ground seismic data combined mining system and a well drive data processing method based on well distributed optical fiber acoustic wave sensing technology.

Background technique

Seismic waves are vibrations that propagate from the source of an earthquake to all directions, and refer to elastic waves that radiate from the source to the surrounding area. According to the propagation mode, it can be divided into three types: longitudinal wave (P wave), transverse wave (S wave) (both longitudinal wave and transverse wave belong to body wave) and surface wave (L wave). When an earthquake occurs, the medium in the epicenter area ruptures and moves rapidly, and this disturbance constitutes a wave source. Due to the continuity of the earth's medium, such fluctuations spread to the interior and surface of the earth, forming elastic waves in the continuum. The propagation velocity of seismic waves varies with different propagation media, usually related to rock type, confining pressure, rock structure and other geological factors.

Seismic exploration refers to a geophysical exploration method that infers the nature and shape of underground rock formations by observing and analyzing the propagation law of seismic waves generated by artificial earthquakes by using the difference in elasticity and density of underground media caused by artificial excitation. Seismic exploration is the most important and most effective method to solve oil and gas exploration problems in geophysical exploration. It is an important means of exploring oil and natural gas resources before drilling, and it is also widely used in coalfield and engineering geological exploration, regional geological research and crustal research.

Seismic exploration is to use artificial methods to cause crustal vibration (such as detonator or explosive explosion, heavy hammer falling or knocking, electric spark or piezoelectric crystal or air gun source excited in water or well, vibrator vibration), and then use precision instruments. The vibration information of each receiving point on the ground after the explosion is recorded according to a certain observation method, and the characteristics of the underground geological structure are inferred by using the result data obtained after a series of processing of the original recorded information. The seismic waves are artificially excited on the surface, and when they propagate underground, the seismic waves will be reflected and refracted when encountering the interface of rock layers with different medium properties. The received seismic wave signal is related to the characteristics of the source, the location of the detection point, and the nature and structure of the underground rock strata through which the seismic wave passes. By processing and interpreting seismic wave records, the properties and morphology of subsurface rock formations can be inferred.

In the process of processing and interpreting the seismic data acquired by seismic exploration, it is one of the necessary and very important steps to calculate the velocity of various seismic waves propagating in the formation and the elastic or viscoelastic parameters of the underground medium (strata or rock formation). one. If the seismic wave velocity of the subterranean formation and the elastic or viscoelastic parameters of the subterranean medium (stratum or rock formation) cannot be accurately obtained, it will be very disadvantageous or impossible to process and interpret the subsequent seismic data. Therefore, accurate measurement and calculation of the seismic wave velocity of the subsurface and the elastic or viscoelastic parameters of the subsurface medium (strata or rock formation) is one of the primary tasks in the processing and interpretation of seismic exploration data.

Existing seismic data acquisition systems on the ground and in wells use general-purpose moving-coil or digital ground single-component or three-component geophones and moving-coil three-component geophone arrays in wells for well-ground joint stereo synchronization Acquire surface and borehole seismic data. Due to the heavy weight and high cost of the existing moving-coil three-component geophones in the well, the logging cable can deploy at most 100-level moving-coil three-component geophones in the well at one time to collect seismic data in the whole well section at a depth of several thousand meters. It is necessary to move or lift the moving coil three-component geophone array in the well several times, and each time the moving coil three-component geophone array in the well is lifted, all artificial excitation sources on the ground (dynamite or heavy hammer or electric spark or air gun or piezoelectric crystal) (or vibroseis) point needs to be re-excited once, which not only causes the high cost of the seismic data collected by the well-ground joint three-dimensional acquisition, but also makes it difficult to ensure that the energy and spectrum of each excitation are consistent for repeated excitation at each source point. Each coupling between the source and the ground is also exactly the same. For these well-known reasons, the well-ground combined stereo synchronous acquisition of surface and wellbore seismic data is very difficult for general-purpose moving-coil or digital surface single- or three-component geophones and moving-coil three-component geophone arrays in wells. Difficult to popularize and apply.

Well-ground seismic combined three-dimensional exploration technology is a new seismic exploration method formed by the combination of surface seismic exploration and well seismic exploration technology. The imaging accuracy of the exploration area is improved, and the signal-to-noise ratio and resolution of the reflection of the target layer are improved. It is beneficial to identify special geological bodies, carry out detailed prediction and evaluation of reservoirs, study sand bodies and lithological traps; finely study the structure of strata around the well, the variation characteristics of reservoirs and oil layers, and is a new type of seismic exploration technology. .

现有的已知技术，例如：专利申请号为201611224463.1、201810499456.5、201710747770.6、201410140366.9、200710141556.2、201711453533.5、200810138351.3、201110436378.2、200820026051.1、201010134001.7、201510673600.9、201420694552.2、201811088989.0、201280044880.1、201711066824.9、201511001188.2、201280061525.5中均公开了Well-ground seismic combined three-dimensional exploration technical solution, but still exists: the three-component geophone array in the well needs to be moved or lifted several times to collect the well-bore seismic data for the entire well section. Repeated excitation of all artificial excitation sources on the ground (dynamite or heavy hammer or electric spark or piezoelectric crystal or air gun or vibrator), the repeated excitation energy of each source point is inconsistent, the frequency spectrum is inconsistent, and the coupling between the source and the ground is not completely consistent These problems will affect the subsequent ground seismic data processing and imaging accuracy.

Utility model content

In order to solve the above-mentioned technical problems, the utility model discloses a combined well-ground seismic data mining system and a well-drive data processing method based on distributed optical fiber acoustic wave sensing. High-density, high-efficiency, high-resolution, low-cost well-ground combined three-dimensional seismic exploration technology for oil and gas resource exploration and comprehensive evaluation.

One of the technical solutions adopted by the utility model is: a combined well-ground seismic data mining system based on distributed optical fiber acoustic wave sensing, comprising: drilling 11, distributed optical fiber acoustic wave sensing armored optical cables 12 in the well laid along the entire well section, ground A wired geophone 13, an artificial source excitation point 14, a cable 15, and a ground seismic and borehole seismic data acquisition vehicle 16, the ground wired geophone 13 is connected to the cable 15, and the distributed fiber optic acoustic wave sensing armor in the well is laid along the entire well section. The optical cable 12 is connected to the ground seismic and well seismic data acquisition vehicle 16, the surface wired geophone 13, the well distributed optical fiber acoustic wave sensing armored optical cable 12 along the entire well section, and the surface seismic and well seismic data acquisition vehicles 16 are synchronized at the same time. Acquire and record seismic data.

Replace the cable 15 with an armored optoelectronic composite cable.

The ground detector 13 is: wired single-component or three-component moving coil detector, wired single-component or three-component digital detector, wired single-component or three-component acceleration detector, wired single-component or three-component fiber optic detector One of wireless single-component or three-component moving coil detectors, wireless single-component or three-component digital detectors, wireless single-component or three-component acceleration detectors, and wireless single-component or three-component fiber optic detectors.

The artificial source excitation point 14 is one of a ground explosive source, a heavy hammer source, an electric spark source, a piezoelectric crystal source, an air gun source, and a vibroseis.

The second technical scheme adopted by the utility model is: based on distributed optical fiber acoustic wave sensing well-ground seismic data combined mining system, including: drilling 21, three-component geophones 22 in the whole well section, ground wire geophones 23, artificial seismic source excitation Point 24, cable 25 and surface seismic and downhole seismic data acquisition vehicle 26, the surface wired geophone 23 is connected to the cable 25, and the full well section downhole geophone 22 is connected to surface seismic and downhole seismic data acquisition through armored logging cables The vehicle 26, the surface wired geophone 23, the downhole geophone 22 in the whole well section, and the surface seismic and downhole seismic data acquisition vehicle 26 simultaneously collect and record seismic data.

The third technical solution adopted by the utility model is: a combined well-ground seismic data mining system based on distributed optical fiber acoustic wave sensing, including: drilling 31 , distributed optical fiber acoustic wave sensing armored optical cable 32 in the whole well section, and ground wireless geophones 33. The artificial source excitation point 34 and the seismic data acquisition vehicle 35 in the well. The distributed fiber optic acoustic wave sensing armored optical cable 32 in the well is connected to the seismic data acquisition vehicle 35 in the well. The distributed fiber optic acoustic wave sensing armored optical cable 32 in the well and the seismic data acquisition vehicle 35 in the well simultaneously collect and record seismic data simultaneously.

The fourth technical solution adopted by the utility model is: a combined well-ground seismic data mining system based on distributed optical fiber acoustic wave sensing, including: drilling 41, three-component geophones 42 in the well of the whole well section, ground wireless geophones 43, artificial seismic source excitation Point 44 and the wellbore seismic data acquisition vehicle 45, the whole well section well geophone 42 is connected to the wellbore seismic data acquisition vehicle 45, the surface wireless geophone 43, the whole well section well geophone 42 and the wellbore seismic data acquisition vehicle 45 are synchronized Simultaneous acquisition and recording of seismic data.

Beneficial effects of the present utility model: The utility model utilizes wired or wireless node-type single-component or three-component geophones arranged on the ground and source signals evenly or non-uniformly arranged on the ground, and utilizes conventional seismic data recording instruments and distributed optical fibers. Acoustic Sensing (DAS) modulation and demodulation system quickly, efficiently and cost-effectively acquires ground 3D seismic data and downhole seismic data along the downhole distributed fiber optic acoustic sensing armored cable. The utility model can realize high-density, high-efficiency, high-resolution and low-cost combined well-ground three-dimensional seismic exploration. The results of seismic data processing in the well can extract wavelets, identify multiples, obtain the average and interlayer P-wave velocity, shear-wave velocity, obtain the velocity anisotropy of P-wave velocity and shear-wave velocity in different azimuths, calculate P-wave and shear-wave velocity Attenuation coefficients (characteristics) propagating in the underground medium, and then finely and accurately establish the two-dimensional or three-dimensional seismic wave velocity model of the underground medium around the well and the two-dimensional or three-dimensional elastic or viscoelastic parameter model of the underground medium, and analyze the three-dimensional surface seismic data. Perform static correction processing, multiple removal processing, amplitude recovery processing, subsequent resolution enhancement processing of 3D ground seismic data, anisotropic migration imaging and Q compensation or combined Q migration imaging of prestack gather data, and Fine exploration and comprehensive evaluation of oil and gas resources through comprehensive interpretation technology.

Description of drawings

FIG. 1 is a schematic diagram of a seismic data acquisition system corresponding to Embodiment 1 of the present invention.

2 is a schematic diagram of a seismic data acquisition system corresponding to Embodiment 2 of the present invention.

3 is a schematic diagram of a seismic data acquisition system corresponding to Embodiment 3 of the present invention.

4 is a schematic diagram of a seismic data acquisition system corresponding to Embodiment 4 of the present invention.

Reference numerals: 11-drilling; 12-distributed fiber optic acoustic wave sensing armored optical cable in the whole well section; 13-ground wired single-component or three-component moving coil type or digital or acceleration type or fiber optic detector; 14-ground Explosive source or heavy hammer source or electric spark source or piezoelectric crystal source or air gun source or vibroseis; 15- Geophone connecting cable or fiber optic geophone connecting armored optical cable, 16- Ground seismic and well seismic data acquisition vehicle; 21 -Drilling; 22-Three-component moving coil or digital or acceleration or fiber optic geophone array in the whole well section; 23- Surface single-component or three-component moving coil or digital or acceleration or fiber-optic geophone; 24- Ground explosive source or heavy hammer source or electric spark source or piezoelectric crystal source or air gun source or vibroseis; 25- Geophone connecting cable or fiber optic geophone connecting armored optical cable, 26- Ground seismic and well seismic data acquisition vehicle; 31-drilling; 32-distributed fiber optic acoustic wave sensing armored optical cable in the whole well section; 33-ground wireless single-component or three-component moving coil or digital or acceleration or fiber-optic detector; 34-ground explosive source or heavy Hammer source or electric spark source or piezoelectric crystal source or air gun source or vibroseis; 35-well seismic data acquisition vehicle; 41-drilling; 42-three-component moving coil type or digital type or acceleration type or optical fiber in the whole well section Geophone array; 43-Ground wireless single-component or three-component moving coil type or digital or acceleration type or fiber optic detector; 44-Ground explosive source or heavy hammer source or electric spark source or piezoelectric crystal source or air gun source or can Vibration source; 45-well seismic data acquisition vehicle.

Detailed ways

In order to facilitate those skilled in the art to understand the technical content of the present invention, the content of the present invention will be further explained below with reference to the accompanying drawings.

Example 1

The present utility model will be described in detail below in conjunction with the accompanying drawings.

FIG. 1 is a schematic diagram of a distributed optical fiber acoustic wave sensing armored optical cable and a ground wired seismic data acquisition system in a well targeted by the present utility model. The well-ground combined distributed optical fiber acoustic wave sensing seismic data acquisition system is composed of the drilling 11 shown in Figure 1, the distributed optical fiber acoustic wave sensing armored optical cable 12 in the whole well section, and the ground wired single-component or three-component moving coil or Digital or acceleration or fiber optic geophones 13, ground explosive sources or heavy hammer sources or spark sources or piezoelectric crystal sources or air gun sources or vibrators 14, geophone connecting cables or armored fiber optic cables 15 and ground seismic and wellbore sources Seismic data acquisition vehicle 16 is composed. The recording instruments used in the distributed fiber optic acoustic wave sensing armored fiber optic cable and the ground single-component or three-component fiber optic detector 13 are all phase-sensitive optical time domain reflectometers (Φ-OTDR), which are installed in the surface seismic and well seismic data acquisition. Inside car 16.

In the well-ground combined three-dimensional seismic data acquisition operation, firstly, in the drilling 11, the distributed fiber optic acoustic wave sensing armored optical cable 12 in the well is laid along the whole well section, and the single-component or three-component wiring is arranged on the ground according to the pre-designed monitoring network. Moving coil type or digital type or acceleration type or fiber optic detector 13, and then laying explosive source or heavy hammer source or electric spark source or piezoelectric crystal source or air gun source or vibrator 14 at the pre-designed source position, and finally along the The artificial seismic source excitation points 14 pre-designed on the ground are excited point by point, and the cables or armored optical cables 15 are connected through the geophones 13 arranged on the construction site, and the distributed fiber optic acoustic wave sensing armored optical cables 12 in the well and ground seismic sensors are laid along the whole well section. Simultaneously collects and records ground and borehole seismic data synchronously with the borehole seismic data acquisition vehicle 16 to realize borehole-ground joint three-dimensional seismic exploration.

The downhole seismic data acquisition system consists of distributed fiber optic acoustic wave sensing armored optical cables along the entire well section or downhole three-component moving coil or digital or acceleration or fiber optic geophone arrays 12 and ground along the entire well section. The data acquisition vehicle 16 is composed, the ground seismic data acquisition system is composed of a wired or wireless node type single-component or three-component moving coil type geophone or a digital geophone or an acceleration geophone or an optical fiber geophone 13 and a surface seismic data acquisition vehicle 16. ─The working source 14 of the ground-integrated optical fiber seismic data acquisition system can be ground explosive source, heavy hammer source, electric spark source, piezoelectric crystal source, air gun source, or vibroseis.

Example 2

The present utility model will be described in detail below in conjunction with the accompanying drawings.

2 is a schematic diagram of a three-component geophone array in a well and a ground wired seismic data acquisition system targeted by the present invention. The well-surface combined fiber-optic seismic data acquisition system is composed of the drilling 21 shown in Figure 2, the three-component moving coil type or digital or acceleration type or fiber-optic detector array 22 in the whole well section, and the ground wired node type single-component or three-component Moving coil or digital or acceleration or fiber optic geophones 23, ground explosive sources or heavy hammer sources or spark sources or piezoelectric crystal sources or air gun sources or vibrators 24, cables or armored fiber optic cables 25 and well seismic data The collection cart 26 is composed. The recording instruments used in the three-component fiber geophone array 22 in the well are all phase-sensitive optical time domain reflectometers (Φ-OTDR), which are placed in the surface seismic and well seismic data acquisition vehicles 26 .

In the well-ground combined three-dimensional seismic data acquisition operation, firstly, the downhole three-component moving coil type or digital or acceleration type or fiber optic detector array 22 is arranged along the whole well section in the drilling 21. A single-component or three-component moving coil type or digital type or acceleration type or fiber optic detector 23 is arranged, and then an explosive source or a weight source or an electric spark source or a piezoelectric crystal source or an air gun source is arranged at the pre-designed source position. The vibroseis 24 is finally excited point by point along the pre-designed artificial source excitation points 24 on the ground, and is connected to the cable or armored optical cable 25 through the geophone 23 laid on the construction site, the three-component geophone array 22 in the well, and the seismic data acquisition in the well The vehicle 26 simultaneously collects and records seismic data on the ground and in the well, so as to realize the combined three-dimensional seismic exploration of the well and the ground.

Example 3

The present utility model will be described in detail below in conjunction with the accompanying drawings.

FIG. 3 is a schematic diagram of the distributed optical fiber acoustic wave sensing armored optical cable in the well and the ground wireless node type seismic data acquisition system for the utility model. The well-surface combined optical fiber seismic data acquisition system is composed of the drilling 31 shown in Figure 3, the distributed fiber optic acoustic wave sensing armored optical cable 32 in the well section, the ground wireless node type single-component or three-component moving coil type or digital or An acceleration type or fiber optic detector 33 , a ground explosive source or a heavy hammer source or an electric spark source or a piezoelectric crystal source or an air gun source or a vibroseis 34 and a well seismic data acquisition vehicle 35 are composed. The recording instrument used in the distributed fiber optic acoustic wave sensing armored optical cable 32 in the well is a phase-sensitive optical time domain reflectometer (Φ-OTDR), which is installed in the surface seismic and well seismic data acquisition vehicle 35 .

In the well-ground combined three-dimensional seismic data acquisition operation, firstly, in the drilling 31, lay the well distributed fiber optic acoustic wave sensing armored optical cable 32 along the whole well section, and lay out the wireless node single-component or single-component or Three-component moving coil type or digital type or acceleration type or fiber optic detector 33, and then arrange an explosive source or a heavy hammer source or an electric spark source or a piezoelectric crystal source or an air gun source or a vibrator source 34 at the pre-designed source position, Finally, the artificial seismic source excitation points 34 pre-designed on the ground are excited point by point and through the wireless node-type single-component or three-component detectors 33 laid on the construction site, the distributed fiber optic acoustic wave sensing armored optical cable 32 in the well section and the wellbore The seismic data acquisition vehicle 35 simultaneously acquires and records seismic data on the ground and in the well, so as to realize the combined three-dimensional seismic exploration of the well and the surface.

Example 4

The present utility model will be described in detail below in conjunction with the accompanying drawings.

4 is a schematic diagram of a three-component geophone array in a well and a ground wireless node type seismic data acquisition system targeted by the present invention. The well-ground joint distributed optical fiber acoustic wave sensing seismic data acquisition system is composed of the well 41 shown in FIG. Component moving coil type or digital type or acceleration type or fiber optic detector 43, ground explosive source or weight hammer source or electric spark source or piezoelectric crystal source or air gun source or vibrator 44 and ground seismic and well seismic data acquisition vehicle 45 composition. The recording instruments used in the three-component fiber optic detector array 42 in the well and the single-component or three-component fiber optic detector on the surface 43 are all phase-sensitive optical time domain reflectometers (Φ-OTDR), which are installed in the surface seismic and well seismic data acquisition vehicles 45 Inside.

In the well-ground combined three-dimensional seismic data acquisition operation, firstly, the downhole three-component moving coil type or digital or acceleration type or fiber optic detector array 42 is arranged along the whole well section in the drilling 41, and the pre-designed survey network is used on the ground. Deploy wireless node type single-component or three-component moving coil type or digital or acceleration type or fiber optic detector 43, and then arrange explosive source or weight source or electric spark source or piezoelectric crystal source or air gun at the pre-designed source position The seismic source or vibroseis 4 is finally excited point by point along the pre-designed artificial seismic source excitation point 44 on the ground, and is excited by the wireless node single-component or three-component detector 43, the three-component detector array 42 in the well and the The seismic data acquisition vehicle 45 simultaneously acquires and records the ground and in-well seismic data, so as to realize the combined well-ground three-dimensional seismic exploration.

The recording instrument used in the well-distributed fiber-optic acoustic wave sensing armored fiber-optic cable or the downhole three-component fiber-optic detector array in the above-mentioned 4 embodiments is a phase-sensitive optical time domain reflectometer (Φ-OTDR), which is placed in the ground seismic and wellbore Seismic data collection inside the car.

The ground seismic data acquisition system in the above four embodiments may be a two-dimensional or three-dimensional wired or wireless node single-component or three-component moving coil type or digital type or acceleration type or fiber optic detector arranged on the ground.

The recording instrument used in the ground wired single-component or three-component fiber optic detector is a phase-sensitive optical time domain reflectometer (Φ-OTDR), which is placed in a vehicle for collecting ground seismic and borehole seismic data.

The ground source may be an explosive source, a heavy hammer source, or an electric spark source, or a piezoelectric crystal source, or an air gun source, or a vibroseis source.

The geophones in the ground seismic data acquisition system are equally or unequally spaced from several meters to several tens of meters.

The space sampling interval of the downhole distributed optical fiber acoustic wave sensing armored optical cable is equal to the distance of 0.1 meters to 10 meters.

The downhole three-component geophones are equally or unequally spaced in the downhole from several meters to several tens of meters.

Those of ordinary skill in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims (7)

1. Seismic data joint mining system based on distributed optical fiber acoustic sensing well is characterized by comprising: the system comprises a well drilling and a full-well-section well distributed optical fiber acoustic wave sensing armored optical cable, a ground wired or wireless detector, an artificial seismic source excitation point and a well seismic data acquisition vehicle, wherein the full-well-section well distributed optical fiber acoustic wave sensing armored optical cable is connected with the well seismic data acquisition vehicle, and the ground wired or wireless detector and the full-well-section well distributed optical fiber acoustic wave sensing armored optical cable synchronously acquire and record seismic data at the same time.

2. The distributed fiber optic acoustic wave sensing based well-ground seismic data cogeneration system of claim 1, wherein the artificial source excitation points are: one of a ground explosive source, a heavy hammer source, an electric spark source, a piezoelectric crystal source, an air gun source and a controllable source.

3. The distributed fiber optic acoustic wave sensing based uphole seismic data co-production system of claim 2, wherein the distributed fiber optic acoustic wave sensing armored cable in the full-interval downhole is replaced with a full-interval downhole three-component geophone.

4. The system for simultaneous recovery of seismic data from a well and a ground based on distributed fiber optic acoustic wave sensing according to any one of claims 1 to 3, wherein the ground wireless detectors are replaced by ground wired detectors, the borehole seismic data collection vehicle is replaced by a ground seismic and borehole seismic data collection vehicle, and further comprising cables, and the ground wired detectors are connected with the ground seismic and borehole seismic data collection vehicles through cables.

5. The system for jointly acquiring seismic data based on a distributed optical fiber acoustic wave sensing well according to any one of claims 1 to 3, wherein the ground wireless geophones are: one of a wireless single-component moving-coil detector, a wireless single-component digital detector, a wireless single-component acceleration detector and a wireless single-component optical fiber detector.

6. The distributed optical fiber acoustic wave sensing borehole seismic data co-production system according to claim 3, wherein the full-interval borehole geophone is: one of a wired three-component moving-coil detector, a wired three-component digital detector, a wired three-component acceleration detector and a wired three-component optical fiber detector.

7. The system of claim 4, wherein the surface line detectors are: a wired single-component or three-component moving-coil detector, a wired single-component or three-component digital detector, a wired single-component or three-component acceleration detector, and a wired single-component or three-component optical fiber detector.

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