CN101872026B

CN101872026B - Natural electromagnetic radiation sounding multichannel detection method

Info

Publication number: CN101872026B
Application number: CN2010102042212A
Authority: CN
Inventors: 岳棋柱
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-06-21
Filing date: 2010-06-21
Publication date: 2012-06-27
Anticipated expiration: 2030-06-21
Also published as: CN101872026A

Abstract

The invention discloses a natural electromagnetic radiation sounding multichannel detection method. An effect of sounding by using the same natural field source at the same time in a wide range is achieved by adopting a multi-channel ground detecting system; and an influence that natural field intensity and frequency distribution change along with time when performing single-point detection is overcome to realize fine contrast between detection results so as to improve detection quality and work efficiency. The invention discloses a contrast method for converting dimensionless relative resistivity (rhor) of a concerned rock stratum into dimensional apparent resistivity (rhoa) or resistivity (rho), so that a geological interpretation level of the detection results is improved. Two-way data transmission link is established between a computer and a remote data processing center for reprocessing a preprocessed result of an exploratory area and providing a sounding result map. The data processing centre grasps work progress situation of each exploratory area at any time and provides information for adjusting work arrangement of the exploratory area when necessary.

Description

A kind of natural electromagnetic radiation sounding multichannel detection method

Technical field

The present invention relates to a kind of natural electromagnetic radiation sounding detection method, particularly a kind of natural electromagnetic radiation sounding multichannel detection method.

Background technology

The natural electromagnetic radiation sounding detection method; It is a natural electromagnetism field source that utilizes natural electromagnetic radiation to form; Survey subsurface geologic structures and the various mineral resources relevant with laminar formation; Comprise: oil, rock gas, coal, water, also can be applicable to engineering geology, archaeology and geological hazards prediction, comprising: landslide, earthquake forecasting research." method of natural electromagnetic radiation sounding Detection Techniques and device thereof (ZL98101408.9) " realized utilizing the single component of natural electromagnetic field; It is electric field component; Carry out single-point at the near surface free space and survey, the nondimensional relative resistance rate in rock stratum (ρ under the measuring point is provided _r) with the histogram that the degree of depth (h) changes, be convenient to successively contrast with the drilling well result who finally directly detects subsurface picture, and become the Detection Techniques with practical value.

Method and device thereof that the method for natural electromagnetic radiation sounding technology and device (ZL98101408.9) thereof are narrated are compared with typical magnetotelluric method; At aspect of performance: improved to the electrical interfacial depth of burial directly related with the rock stratum interphase change, the resolution characteristic of the horizontal change of the electrical variation of rock stratum, underground geologic bodies; The scope of separating, the maximum verification investigation depth of having dwindled the result of detection geologic interpretation reach seven kms, formation dip in 90 degree scopes more; Detection operations does not receive the restriction of formation dip; Can be applicable to the geologic structure complex area, and on the water surface, survey.In use: improved work efficiency, realized the sniffer portability, receive the surface condition restriction less, do not receive the influence of earth shock, power frequency is disturbed the inhibition ability arranged, the ecologic environment in exploratory area is had no adverse effects.Any geophysical exploration method is called for short geophysical prospecting method and all has its most suitable acquisition environment, also has some limitations simultaneously inevitably.Except fully utilizing multiple geophysical prospecting method, improve outside the detection quality, still need update for geophysical prospecting method itself.Use this method in different regions for many years, carried out having the detection operations of actual effect, and, increased the observation verifying data, but also experienced this detection method, have following deficiency equally the working mechanism of detection method.

There is multiple factor to impel natural electromagnetic field in time in continuous variation, existing single-point detection method, because observation is different constantly, variation has also been experienced in the incident field intensity of the natural electromagnetic field that each measuring point utilized and frequency distribution.Meticulous contrast to result of detection between each measuring point brings adverse influence; The relative resistance rate that mainly is rock stratum in the result of detection is except the variation of reflection subterranean strata physical property; Also include the variation of natural incident field intensity and frequency distribution; So that adjacent measuring point result of detection can produce query when contrasting, even does the geologic interpretation that makes mistake.For example, when the contrast interruption in the process of following the trail of zone of interest continuously, occurring, at first to get rid of the influence that non-incident field source changes, just can make clear and definite geologic interpretation.

Its result of detection of existing method only can provide, the nondimensional relative resistance rate in rock stratum (ρ under the measuring point _r) histogram that changes with the degree of depth (h), and, rock stratum nondimensional relative resistance rate (ρ _r) no longer change the linear relationship that keeps strict with the degree of depth (h), when the depth range of surveying enlarged, this nonlinear relationship can be more obvious.Only according to the height of the relative resistance rate of rock stratum still can not, the physical property of rock stratum is made reasonable supposition, thereby to the geologic interpretation deleterious impact of result of detection.

Summary of the invention

The object of the present invention is to provide a kind of natural electromagnetic radiation sounding multichannel detection method; Solve when adopting single-point to survey; Because of natural field source changes in time; Survey and contain the influence that natural field source changes in the record, especially survey, be unfavorable in the data contrast, obtaining the meticulous variation of reflection geological condition and the nondimensional problem of result of detection of the rock stratum of paying close attention to for the unconspicuous slice of deep resistivity difference.

A kind of concrete steps of natural electromagnetic radiation sounding multichannel detection method are:

The first step makes up detection system

A kind of natural electromagnetic radiation sounding multichannel detection method realizes that through a kind of multiple tracks detection system this detection system comprises: a plurality of detection subsystem and remote data processing center.Wherein, detection subsystem comprises: electric-field sensor, prime amplifier, post amplifier, double balanced mixer, narrowband intermediate frequency wave filter, accurate wave detector, feedback circuit, local signal generator, peak detector, valley wave detector, subtracter, totalizer, divider, A/D converter, D/A converter, marker generator and computing machine.The data that the ground location device is gathered and stored are transferred to remote data processing center through the networking after the computing machine pre-service.

Second step was confirmed the measuring point arrangement form

The measuring point arrangement form of each exploratory area detection subsystem comprises: the section that the section of measuring point is arranged, the square formation of measuring point is arranged and the sea is surveyed is arranged.According to the geological condition in exploratory area and specific requirement to detection mission, confirm that each exploratory area detection subsystem adopts above-mentioned a kind of measuring point arrangement form, or the combination of above-mentioned several kinds of measuring point arrangement forms, and definite measuring point concrete parameter of arranging.

The section of measuring point is arranged:

When the measuring point number that is arranged along a straight line surpasses 5 measuring points; The section that promptly can be considered measuring point is arranged; Section is arranged along the pendage direction of estimating; Measuring point is decided according to the level of detail of concrete object of surveying and detection at interval, and measuring point is spaced apart 20 meters-50 meters, uses 6-12 tread sniffers to work simultaneously.Be used for the ore bed of estimating, the structure on stratum are tentatively surveyed.When section needs overtime, the terminal measuring point of section overlaps with the head end point position of its prolongation section, and it is different constantly because of surveying to be used for inspection, the system deviation between the section.

The square formation of measuring point is arranged

According to the preliminary result of detection that the section of measuring point is arranged, to carry out the square formation of measuring point and arrange detection, the square formation of measuring point is made up of many horizontal sections and longitudinal profile, and measuring point interval and profile intervals are 20 meters-50 meters, use 6-12 tread sniffers to work simultaneously.Ore bed, stratal configuration are laterally being surveyed with space distribution longitudinally.Wherein have common measuring point and mutually perpendicular section; Be used to survey the rock stratum vergence direction and inclination angle, survey the rock stratum, deep under the native state of high temperature and high pressure; The direction of terrestrial stress and the space distribution of its amplitude and terrestrial stress space distribution over time, for earthquake forecasting research provides reference information.The scale of square formation is confirmed by the quantity of the ground location device that is adopted; The square formation of measuring point is along laterally or during longitudinal extension of square formation; The location overlap of the edge section of extension square formation and the edge section of former square formation, it is different constantly because of surveying to be used for inspection, the system deviation between each square formation.

Measuring point when surveying on the sea is arranged

When surveying across the sea, because the influence of marine stream, point position is difficult for fixing, keeps measuring point at interval with floating hawser, and the section that constitutes measuring point is arranged.Be used for ore bed, the stratal configuration estimated are tentatively surveyed.Adopt many parallel sections to arrange, to laterally surveying of ore bed, stratal configuration with space distribution longitudinally.Connection section with repeat station is set between each bar section, and it is different constantly because of surveying to be used for inspection, the system deviation between each section.The ground location device is fixed on the top of buoy; Be used to avoid sniffer to contact the sealing problem that seawater faces; Also since the conductivity of free space and seawater differ greatly, therefore, in the time of also can obtaining signal and under the sea, return free space; The benefit that electric field intensity is enhanced, the geographic position of measuring point is confirmed by Global Positioning System (GPS).

The 3rd step was guaranteed the consistance of each ground sniffer multiple tracks detection performance parameter of a plurality of subsystems

According to requirement to the resolution characteristic of investigation depth scope and investigation depth, frequency span, operating frequency range and the frequency interval of adjustment channel gain, wave filter, the relative deviation that makes parameters is less than ± 5%.

The 4th step each road sniffer of record is in the relative altitude on the face of land

Before detection operations, the face of land relative altitude of each measuring point is measured.Because investigation depth is calculated from the face of land, need the relative altitude of each ground, road sniffer of record on the face of land,

The 5th step was obtained the moment of each same opening entry in road

In order to obtain the record that each ground, road sniffer synchronization begins; After each ground, road sniffer start; The operator utilizes marker generator when surveying, and to each ground sniffer, sends fixed frequency signal; As each ground, road sniffer opening entry distinguishing mark constantly, and the moment of writing down each opening entry.

The 6th step utilized the ground location device to gather detection data

The ground location device adopts the arrowband mode, observation near surface space electric field vertical component

In order to receive near surface electric field vertical component

Adopt the board-like sensor of capacitance pole to convert electric field component to corresponding electric signal; Impedance matching is amplified and carried out to the feeble signal of electric-field sensor output by prime amplifier, and further increase signal amplitude by post amplifier; Adopt converter technique to carry out narrow-band filtering at the signal in the whole audiorange; The signal that the local signal generator of post amplifier and frequency adjustable is exported is transported to double balanced mixer simultaneously, by the output signal extraction difference frequency signal of narrowband intermediate frequency wave filter from double balanced mixer; The frequency of operation of local signal generator is higher than the centre frequency of narrowband intermediate frequency wave filter, and the difference on the frequency of the two is the frequency F of measured signal; Feedback circuit acts on local signal generator, the required frequency stability of local signal generator when guaranteeing up-conversion; The amplitude of the difference frequency signal that the narrowband intermediate frequency wave filter is separated out is directly proportional with the signal amplitude that post amplifier is exported and does corresponding variation in time; Detect the envelope signal of difference frequency signal, the vertical component of the amplitude of envelope signal and near surface space electric field by accurate wave detector

A certain frequency component be directly proportional; Its concrete frequency values depends on selected local signal generator output signal frequency; Envelope signal detects peak-peak V through peak detector and valley wave detector _PmaxWith minimum valley V _TminBy totalizer, subtracter and divider are to V _PmaxAnd V _TminCarry out simulation trial, by formula the difference DELTA of peak-peak and minimum peak is tried to achieve in (1),

Δ=V _Pmax-V _Tmin... ... ... ... ... ... ... .. (1) by formula (2) tries to achieve the additive value ∑ of peak-peak and minimum peak,

∑=V _Pmax+ V _Tmin... ... ... ... ... ... ... .. (2) and by formula (3) try to achieve the K value by the ratio of Δ value and ∑ value

K＝Δ/∑.........................................。(3)

Investigation depth scope on the estimation relies on and regulates local signal generator institute output signal frequency, sets the frequency range of corresponding measured signal, chooses the frequency interval of discrete measured signal according to the level of detail of surveying; Local signal generator of every setting when manually-operated; Can be according to the difference of the centre frequency of local signal generator and narrowband intermediate frequency wave filter; Try to achieve frequency F and the corresponding Δ value and the K value of measured signal: in rectangular coordinate system, measured signal frequency F that each is discrete and corresponding Δ value or K value are depicted as F-Δ curve or F-K curve; By the standard of 6 db-losses as definite cutoff frequency; Try to achieve the cutoff frequency value Δ F that is associated with each maximum value and minimal value from F-Δ curve or F-K curve; Utilize following cutoff frequency formula, try to achieve the corresponding investigation depth h of getting, Δ F=(3.76 * 10 with Δ F ⁶)/σ h ², from the maximum value of F-Δ curve relative resistance rate (ρ with rock stratum in minimal value is tried to achieve corresponding depth range _r); At last, draw with represented as histograms and be convenient to the h-ρ that compares with graphic well log _rCurve abbreviates the detection histogram as; The F-K curve is identical with the purposes of F-Δ curve, is used to reduce the time dependent influence of natural electromagnetic radiation.

When surveying automatically, adopt built-in embedded system to carry out detection process control automatically, data acquisition and processing.By the frequency of operation of D/A converter control local signal generator, promptly corresponding investigation depth h, the output signal of accurate wave detector is directly transported to A/D converter; In the data of gathering, to V _PmaxAnd V _TminJudge, calculate Δ, ∑ value and K value, draw the h-ρ of F-Δ curve or F-K curve, each measuring point automatically _rCurve and comprehensive each measuring point h-ρ _rThe sectional view that curve constitutes.

The centralized stores of the 7th step detection data

The computing machine centralized stores is by data, exploratory area measuring point arrangenent diagram and the daily record of work of each ground sniffer transmission.

The quality check of the 8th step record

At first given to each ground sniffer; Each adjacent measuring point is surveyed histogrammic form and is laterally contrasted; When morphological differences is obvious; The adjacent measuring point data of inspection Computer Storage is checked point position according to " exploratory area measuring point arrangenent diagram ", concrete condition when checking detection according to " daily record of work ".Once more to V _PmaxAnd V _TminJudge, and draw the detection histogram of each adjacent measuring point, get rid of the influence that natural electromagnetic field changing factor brings, make each adjacent measuring point survey the horizontal contrast of histogrammic form and obtain confirming.

The 9th step computing machine carries out the data pre-service

Computing machine carries out pre-service to each ground sniffer recorded data, and the pre-service content comprises: survey histogram according to each ground sniffer recorded data and each measuring point, i.e. the h-ρ that representes of represented as histograms _rCurve contrasts the detection histogram of all measuring points comprehensively, obtains the basic condition of exploratory area subsurface geologic structures.Because the vertical component of the natural electric field observed is to be superimposed upon atmospheric envelope ionization is formed owing to shined upon; Intensity up to 120 volts/rice; Cycle is about on the circadian vertical electric field, and observation is different constantly, and high-strength and long cycle vertical electric field makes the cycle of observation signal produce change; And in its correspondent frequency territory, produce frequency displacement, thereby the investigation depth and the thickness of rock stratum is brought influence.In order to improve the precision of surveying absolute depth, the system deviation according to difference produces constantly with each rock stratum of being paid close attention to, is corrected to result of detection constantly at local noon.Owing to the employing multiple tracks is surveyed simultaneously, between the required loaded down with trivial details correction simplified section for measuring point of pointwise was arranged when single-point was surveyed, or the system deviation correction between the measuring point square formation layout, improved the order of accuarcy of correction.This method; Be that the face of land that belongs to each measuring point is the zero point of investigation depth; Utilize the face of land relative altitude of each measuring point write down, the result of detection of each point is corrected to the same reference field of exploratory area known elevation height, further improve and survey the laterally fine degree of contrast of histogram.

The tenth step remote data processing center is carried out data processing

Computing machine utilizes network, gives remote data processing center with detection data pre-service result transmission, and remote data processing center is according to pre-service profiling as a result.Based on exploratory area relevant geologic information and other various physical prospecting data, carry out the geologic structure contrast to surveying result map, comparing result is drawn result map after confirming.

The 11 step remote data processing center is drawn result map

Remote data processing center is drawn two-dimentional pseudo-colours sectional view respectively, or three-dimensional pseudo-colours rock stratum spatial distribution map, to having the three-dimensional pseudo-colours rock stratum spatial distribution map of time parameter, draws corresponding multidimensional pseudo-colours map.

The 12 step remote data processing center is carried out the data contrast

In remote data processing center, geologic information and other the various physical prospecting data relevant according to the exploratory area are carried out the geologic structure contrast once more to surveying result map.When appearance is inconsistent between the data in comparison process; Repeat the processing procedure in the 7th step and the 8th step, result of detection is checked, find the cause and correct; What between above-mentioned inspection affirmation data, occur is inconsistent; And the non-natural electromagnetic field changes the influence bring, still keeps original data corresponding state, makes the contrast of surveying result map and geologic structure obtain affirmation.

The 13 step remote data processing center is that the rock stratum of being paid close attention to provides the parameter with dimension

In order to improve detection quality and geologic interpretation level, the data contrast needs the dimensionless relative resistance rate (ρ with the rock stratum of being paid close attention in the result of detection after obtaining confirming _r) amount to the apparent resistivity that becomes to have dimension (ρ _a) or resistivity (ρ).In order to improve the effect of physical prospecting, at present, extensively adopted multiple geophysical prospecting method comprehensive utilization and geologic interpretation at areal, the result of detection of therefore having ready conditions with other geophysical prospecting method compares, to obtain the effect of comprehensive utilization.

Other all geologic informations and physical prospecting data according to this area, same location, same depth range.To some rock stratum tabulation of being paid close attention to, in tabulation, indicate the top board degree of depth, thickness and the apparent resistivity (ρ of each rock stratum _a) or resistivity (ρ).

According to the detection result map of this area that remote data processing center obtained, same location, same depth range,, in tabulation, indicate the top board degree of depth, thickness and the relative resistance rate (ρ of each rock stratum to some rock stratum tabulation of being paid close attention to _r).

In two kinds of tabulations, find out the top board degree of depth, thickness and the approximating rock stratum of resistivity height.And with the relative resistance rate (ρ of some rock stratum of being paid close attention to _r) be converted into the apparent resistivity (ρ of dimension _a) or the respective value of resistivity (ρ).

After remote data processing center is carried out above-mentioned contrast, make some rock stratum of being paid close attention to obtain having the apparent resistivity (ρ of dimension _a) or resistivity (ρ); Although the resistivity with a kind of rock stratum still has the certain distributed scope, but still can be the rock stratum lithology that judgement pays close attention to reference data is provided, remedied the relative resistance rate (ρ in the result of detection _r) be the influence of nonlinear relationship with investigation depth, owing to adopt multiple tracks to survey, the horizontal contrast degree of result of detection is improved, thereby detection quality and geologic interpretation level are improved.Can be at the above-mentioned comparing result of application in a big way in exploratory area, thus large-area detection quality and geologic interpretation level are improved, and work efficiency also is improved significantly.Remote data processing center is grasped the work progress situation in each exploratory area at any time, and where necessary the work arrangements in exploratory area is proposed adjustment information.

The present invention adopts multiple tracks ground location device to survey, be implemented in a big way in, obtain at synchronization; The effect of utilizing identical natural field source to survey from the detection method aspect, has overcome and has utilized the single component of natural electromagnetic field; Be that electric field component carries out single-point when surveying, the time dependent influence of natural field intensity and frequency distribution, the meticulous contrast between the realization result of detection; Be convenient to judge the horizontal change of zone of interest, thereby improved the detection quality in exploratory area.Dimensionless relative resistance rate (ρ with the rock stratum of paying close attention in the result of detection has been proposed _r), amount to into the apparent resistivity (ρ that there is dimension the rock stratum _a) or the control methods of resistivity (ρ), can improve the geologic interpretation level of result of detection at the comparing result of application in a big way in exploratory area.By computing machine recorded data is carried out pre-service; Between computing machine and the remote data processing center; Set up bidirectional data transfers contact, the various pass physical prospecting data and the geologic information in remote data processing center comprehensive utilization exploratory area are handled respectively the pre-service result in a plurality of exploratory areas again; And will handle resulting detection result map again, in time feed back to each computing machine respectively.At any time grasp the work progress situation that is equipped with the exploratory area, and propose the information of adjustment exploratory area work arrangements where necessary.

Embodiment 1

The first step makes up detection system

Second step was confirmed the measuring point arrangement form

The exploratory area detection subsystem adopts the section of measuring point to arrange and surveys; Section is arranged along the pendage direction of estimating; Set measuring point and be spaced apart 50 meters, use 12 tread sniffers to work simultaneously, be used for the ore bed of estimating, the structure on stratum are tentatively surveyed.

The investigation depth scope is 300 meters to 600 meters, and the resolution characteristic of investigation depth is 10 meters, frequency span, operating frequency range and the frequency interval of adjustment channel gain, wave filter, and the relative deviation that makes parameters is less than ± 5%

The 5th step was obtained the moment of each same opening entry in road

The 6th step utilized the ground location device to gather detection data

In order to receive near surface electric field vertical component

Adopt the board-like sensor of capacitance pole to convert electric field component to corresponding electric signal; Impedance matching is amplified and carried out to the feeble signal of electric-field sensor output by prime amplifier, and further increase signal amplitude by post amplifier; Adopt converter technique to carry out narrow-band filtering at the signal in the whole audiorange; The signal that the local signal generator of post amplifier and frequency adjustable is exported is transported to double balanced mixer simultaneously, by the output signal extraction difference frequency signal of narrowband intermediate frequency wave filter from double balanced mixer; The frequency of operation of local signal generator is higher than the centre frequency of narrowband intermediate frequency wave filter, and the difference on the frequency of the two is the frequency F of measured signal; Feedback circuit acts on local signal generator, the required frequency stability of local signal generator when guaranteeing up-conversion; The amplitude of the difference frequency signal that the narrowband intermediate frequency wave filter is separated out is directly proportional with the signal amplitude that post amplifier is exported and does corresponding variation in time; Detect the envelope signal of difference frequency signal, the vertical component of the amplitude of envelope signal and near surface space electric field by accurate wave detector A certain frequency component be directly proportional; Its concrete frequency values depends on selected local signal generator output signal frequency; Envelope signal detects peak-peak V through peak detector and valley wave detector _PmaxWith minimum valley V _TminBy totalizer, subtracter and divider are to V _PmaxAnd V _TminCarry out simulation trial, by formula the difference DELTA of peak-peak and minimum peak is tried to achieve in (1),

Δ＝V _pmax-V _Tmin.........................................(1)

By formula the additive value ∑ of peak-peak and minimum peak is tried to achieve in (2),

∑＝V _pmax-V _Tmin.........................................(2)

And by formula the K value is tried to achieve by the ratio of Δ value and ∑ value in (3)

K＝Δ/∑.........................................。(3)

Investigation depth scope on the estimation relies on and regulates local signal generator institute output signal frequency, sets the frequency range of corresponding measured signal, chooses the frequency interval of discrete measured signal according to the level of detail of surveying; Local signal generator of every setting when manually-operated; Can be according to the difference of the centre frequency of local signal generator and narrowband intermediate frequency wave filter; Try to achieve frequency F and the corresponding Δ value and the K value of measured signal: in rectangular coordinate system, measured signal frequency F that each is discrete and corresponding Δ value or K value are depicted as F-Δ curve or F-K curve; As the standard of confirming cutoff frequency, try to achieve the cutoff frequency value Δ F that is associated with each maximum value and minimal value by 6 db-losses, utilize following cutoff frequency formula, try to achieve the corresponding investigation depth h of getting with Δ F from F-Δ curve or F-K curve,

ΔF＝(3.76×10 ⁶)/σh ²

From the maximum value of F-Δ curve relative resistance rate ρ with rock stratum in minimal value is tried to achieve corresponding depth range _rAt last, draw with represented as histograms and be convenient to the h-ρ that compares with graphic well log _rCurve abbreviates the detection histogram as; The F-K curve is identical with the purposes of F-Δ curve, is used to reduce the time dependent influence of natural electromagnetic radiation.

The centralized stores of the 7th step detection data

The quality check of the 8th step record

The 9th step computing machine carries out the data pre-service

Computing machine carries out pre-service to each ground sniffer recorded data, and the pre-service content comprises: survey histogram according to each ground sniffer recorded data and each measuring point, i.e. the h-ρ that representes of represented as histograms _rCurve contrasts the detection histogram of all measuring points comprehensively, obtains the basic condition of exploratory area subsurface geologic structures.Because the vertical component of the natural electric field of being observed; Be to be superimposed upon atmospheric envelope owing to shined upon and ionization is formed, intensity up to 120 volts/meter, the cycle is about on the circadian vertical electric field; Observation is different constantly; High-strength and long cycle vertical electric field makes the cycle of observation signal produce change, and in its correspondent frequency territory, produces frequency displacement, thereby the investigation depth and the thickness of rock stratum is brought influence.In order to improve the precision of surveying absolute depth; The system deviation that produces constantly according to difference; With each rock stratum of being paid close attention to, be corrected to result of detection constantly at local noon, owing to adopt multiple tracks to survey simultaneously; System deviation between the required loaded down with trivial details correction simplified section for measuring point of pointwise was arranged when single-point was surveyed is proofreaied and correct, and has improved the order of accuarcy of proofreading and correct.This method; Be that the face of land that belongs to each measuring point is the zero point of investigation depth; Utilize the face of land relative altitude of each measuring point write down, the result of detection of each point is corrected to the same reference field of exploratory area known elevation height, further improve and survey the laterally fine degree of contrast of histogram.

The tenth step remote data processing center is carried out data processing

The 11 step remote data processing center is drawn result map

Remote data processing center is drawn two-dimentional pseudo-colours sectional view.

The 12 step remote data processing center is carried out the data contrast

The psychology center at the teledata place, geologic information and other the various physical prospecting data relevant according to the exploratory area are carried out the geologic structure contrast once more to surveying result map.When appearance is inconsistent between the data in comparison process; Repeat the processing procedure in the 7th step and the 8th step; Result of detection inspection found the cause correct, what between above-mentioned inspection affirmation data contrast, occur is inconsistent, and the non-natural electromagnetic field changes the influence that brings; Still keep original data corresponding state, make the contrast of surveying result map and geologic structure obtain confirming.

In order to improve detection quality and geologic interpretation level, the data contrast needs the dimensionless relative resistance rate (ρ with the rock stratum of being paid close attention in the result of detection after obtaining confirming _r) amount to the apparent resistivity that becomes to have dimension (ρ _a).

Other all geologic informations and physical prospecting data according to this area, same location, same depth range.To some rock stratum tabulation of being paid close attention to, in tabulation, indicate the top board degree of depth, thickness and the apparent resistivity (ρ of each rock stratum _a).

In two kinds of tabulations, find out the top board degree of depth, thickness and the approximating rock stratum of resistivity height.And with the relative resistance rate (ρ of some rock stratum of being paid close attention to _r) be converted into the apparent resistivity (ρ of dimension _a) respective value.

After remote data processing center is carried out above-mentioned contrast, some rock stratum of being paid close attention to have been obtained, have the apparent resistivity (ρ of dimension _a), although the certain distributed scope is still arranged, reference data is provided but still can be the rock stratum lithology that judgement pays close attention to a kind of resistivity of rock stratum, remedied the relative resistance rate (ρ in the result of detection _r) be the influence of nonlinear relationship with investigation depth, owing to adopt multiple tracks to survey, the horizontal contrast degree of result of detection is improved, thereby detection quality and geologic interpretation level are improved.Can be at the above-mentioned comparing result of application in a big way in exploratory area, thus large-area detection quality and geologic interpretation level are improved, and work efficiency also is improved significantly.Remote data processing center is grasped the work progress situation in each exploratory area at any time, and where necessary the work arrangements in exploratory area is proposed adjustment information.

Embodiment 2

The first step makes up detection system

Second step was confirmed the measuring point arrangement form

The exploratory area detection subsystem adopts the square formation arrangement form of measuring point to survey:

The preliminary result of detection of arranging according to the section of measuring point; Carry out the square formation of measuring point and arrange detection; The square formation of measuring point is made up of many horizontal sections and longitudinal profile; Setting measuring point interval and profile intervals is 25 meters, uses 12 tread sniffers, carries out work by the square formation that vertical three measuring points of horizontal four measuring points constitute.Ore bed, stratal configuration are laterally being surveyed with space distribution longitudinally.Wherein have common measuring point and mutually perpendicular section; Be used to survey the rock stratum vergence direction and inclination angle, survey the rock stratum, deep under the native state of high temperature and high pressure; The direction of terrestrial stress and the space distribution of its amplitude; With the terrestrial stress space distribution over time, for earthquake forecasting research provides reference information.The longitudinal profile of square formation and former profile position are overlapping; The square formation of measuring point is along laterally or during longitudinal extension of square formation; The location overlap of the edge section of extension square formation and the edge section of former square formation, it is different constantly because of surveying to be used for inspection, the system deviation between each square formation.

It according to the resolution characteristic that to the investigation depth scope 1 km to 3 km and investigation depth 50 meters requirement.Frequency span, operating frequency range and the frequency interval of adjustment channel gain, wave filter, the relative deviation that makes parameters is less than ± 5%.

The 5th step was obtained the moment of each same opening entry in road

The 6th step utilized the ground location device to gather detection data

The ground location device adopts the arrowband mode, observation near surface space electric field vertical component In order to receive near surface electric field vertical component

Δ＝V _pmax-V _Tmin.........................................(1)

∑＝V _pmax+V _Tmin.........................................(2)

K＝Δ/∑.........................................(3)

Investigation depth scope on the estimation relies on and regulates local signal generator institute output signal frequency, sets the frequency range of corresponding measured signal, chooses the frequency interval of discrete measured signal according to the level of detail of surveying; Local signal generator of every setting when manually-operated; Can be according to the difference of the centre frequency of local signal generator and narrowband intermediate frequency wave filter; Try to achieve frequency F and the corresponding Δ value and the K value of measured signal: in rectangular coordinate system, measured signal frequency F that each is discrete and corresponding Δ value or K value are depicted as F-Δ curve or F-K curve; By the standard of 6 db-losses as definite cutoff frequency; Try to achieve the cutoff frequency value Δ F that is associated with each maximum value and minimal value from F-Δ curve or F-K curve; Utilize following cutoff frequency formula, try to achieve the corresponding investigation depth h of getting, Δ F=(3.76 * 10 with Δ F ⁶)/σ h ²

From the maximum value of F-Δ curve relative resistance rate ρ with rock stratum in minimal value is tried to achieve corresponding depth range _rAt last, draw with represented as histograms and to be convenient to the h-P curve that compares with graphic well log, abbreviate the detection histogram as; The F-K curve is identical with the purposes of F-Δ curve, is used to reduce the time dependent influence of natural electromagnetic radiation.

When surveying automatically, adopt built-in embedded system to carry out detection process control automatically, data acquisition and processing.By the frequency of operation of D/A converter control local signal generator, promptly corresponding investigation depth h, the output signal of accurate wave detector is directly transported to A/D converter; In the data of gathering, to V _Pmax-V _TminV _PmaxAnd V _TminJudge, calculate Δ, ∑ value and K value, draw the h-ρ of F-Δ curve or F-K curve, each measuring point automatically _rCurve and comprehensive each measuring point h-ρ _rThe sectional view that curve constitutes.

The centralized stores of the 7th step detection data

The quality check of the 8th step record

At first given to each ground sniffer; Each adjacent measuring point is surveyed histogrammic form and is laterally contrasted; When morphological differences is obvious; The adjacent measuring point data of inspection Computer Storage is checked point position according to " exploratory area measuring point arrangenent diagram ", concrete condition when checking detection according to " daily record of work ".Once more Vpmax and VTmin are judged, and draw the detection histogram of each adjacent measuring point, get rid of the influence that natural electromagnetic field changing factor brings, make each adjacent measuring point survey the horizontal contrast of histogrammic form and obtain confirming.

The 9th step computing machine carries out the data pre-service

Computing machine carries out pre-service to each ground sniffer recorded data; The pre-service content comprises: survey histogram according to each ground sniffer recorded data and each measuring point; It is the h-P curve that represented as histograms is represented; Detection histogram to all measuring points contrasts comprehensively, obtains the basic condition of exploratory area subsurface geologic structures.Because the vertical component of the natural electric field of being observed; Be to be superimposed upon atmospheric envelope owing to shined upon and ionization is formed, intensity up to 120 volts/meter, the cycle is about on the circadian vertical electric field; Observation is different constantly; High-strength and long cycle vertical electric field makes the cycle of observation signal produce change, and in its correspondent frequency territory, produces frequency displacement, thereby the investigation depth and the thickness of rock stratum is brought influence.In order to improve the precision of surveying absolute depth; System deviation according to difference produces constantly with each rock stratum of being paid close attention to, is corrected to result of detection constantly at local noon; Because adopting multiple tracks surveys simultaneously; Between the required loaded down with trivial details correction simplified section for measuring point of pointwise was arranged when single-point was surveyed, or the system deviation correction between the measuring point square formation layout, and improved the order of accuarcy of proofreading and correct.This method; Be that the face of land that belongs to each measuring point is the zero point of investigation depth; Utilize the face of land relative altitude of each measuring point write down, the result of detection of each point is corrected to the same reference field of exploratory area known elevation height, further improve and survey the laterally fine degree of contrast of histogram.

The tenth step remote data processing center is carried out data processing

The 11 step remote data processing center is drawn result map

Remote data processing center is drawn two-dimentional pseudo-colours sectional view and three-dimensional pseudo-colours rock stratum spatial distribution map, to having the three-dimensional pseudo-colours rock stratum spatial distribution map of time parameter, draws corresponding multidimensional pseudo-colours map.

The 12 step remote data processing center is carried out the data contrast

In remote data processing center, geologic information and other the various physical prospecting data relevant according to the exploratory area are carried out the geologic structure contrast once more to surveying result map.When appearance is inconsistent between the data in comparison process; Repeat the processing procedure in the 7th step and the 8th step; Result of detection inspection found the cause correct, what between above-mentioned inspection affirmation data contrast, occur is inconsistent, and the non-natural electromagnetic field changes the influence that brings; Still keep original data corresponding state, make the contrast of surveying result map and geologic structure obtain confirming.

In order to improve detection quality and geologic interpretation level, the data contrast needs the dimensionless relative resistance rate (ρ with the rock stratum of being paid close attention in the result of detection after obtaining confirming _r) amount to the apparent resistivity that becomes to have dimension (ρ _a).In order to improve the effect of physical prospecting, at present, extensively adopted multiple geophysical prospecting method comprehensive utilization and geologic interpretation at areal, the result of detection of therefore having ready conditions with other geophysical prospecting method compares, to obtain the effect of comprehensive utilization.

Embodiment 3

The first step makes up detection system

Second step was confirmed the measuring point arrangement form

The exploratory area detection subsystem is employed in the measuring point arrangement form when surveying on the sea.

When surveying across the sea, because the influence of marine stream, point position is difficult for fixing, and with floating hawser maintenance measuring point at interval, the section that constitutes measuring point arranges that setting measuring point interval and profile intervals is 50 meters.Be used for ore bed, the stratal configuration estimated are tentatively surveyed.The terminal measuring point of section overlaps with the head end point position of its prolongation section, and it is different constantly because of surveying to be used for inspection, the system deviation between the section.Adopt many parallel sections to arrange, to laterally surveying of ore bed, stratal configuration with space distribution longitudinally.Connection section with repeat station is set between the bar section fully, is used for inspection because of surveying difference constantly, the system deviation between each section.The ground location device is fixed on the top of buoy; Be used to avoid sniffer to contact the sealing problem that seawater faces; Also since the conductivity of free space and seawater differ greatly, therefore, in the time of also can obtaining signal and under the sea, return free space; The benefit that electric field intensity is enhanced, the geographic position of measuring point is confirmed by Global Positioning System (GPS).

According to the resolution characteristic that to the investigation depth scope is 3000 meters to 3500 meters and investigation depth is 100 meters requirement, frequency span, operating frequency range and the frequency interval of adjustment channel gain, wave filter, and the relative deviation that makes parameters is less than ± 5%.

The 5th step was obtained the moment of each same opening entry in road

The 6th step utilized the ground location device to gather detection data

In order to receive near surface electric field vertical component

A certain frequency component be directly proportional; Its concrete frequency values depends on selected local signal generator output signal frequency; Envelope signal detects peak-peak V through peak detector and valley wave detector _PmaxWith minimum valley V _TminBy totalizer, subtracter and divider are to V _PmaxAnd V _TminSimulate fortune V and calculate, by formula the difference DELTA of peak-peak and minimum peak is tried to achieve in (1),

Δ＝V _pmax-V _Tmin.........................................(1)

∑＝V _pmax+V _Tmin.........................................(2)

K＝Δ/∑.........................................。(3)

ΔF＝(3.76×10 ⁶)/σh ²

From the maximum value of F-Δ curve relative resistance rate (ρ with rock stratum in minimal value is tried to achieve corresponding depth range _r); At last, draw with represented as histograms and be convenient to the h-ρ that compares with graphic well log _rCurve abbreviates the detection histogram as; The F-K curve is identical with the purposes of F-Δ curve, is used to reduce the time dependent influence of natural electromagnetic radiation.

The centralized stores of the 7th step detection data

The quality check of the 8th step record

The 9th step computing machine carries out the data pre-service

Computing machine carries out pre-service to each ground sniffer recorded data, and the pre-service content comprises: survey histogram according to each ground sniffer recorded data and each measuring point, i.e. the h-ρ that representes of represented as histograms _rCurve contrasts the detection histogram of all measuring points comprehensively, obtains the basic condition of exploratory area subsurface geologic structures.Because the vertical component of the natural electric field of being observed; Be to be superimposed upon atmospheric envelope owing to shined upon and ionization is formed, intensity up to 120 volts/meter, the cycle is about on the circadian vertical electric field; Observation is different constantly; High-strength and long cycle vertical electric field makes the cycle of observation signal produce change, and in its correspondent frequency territory, produces frequency displacement, thereby the investigation depth and the thickness of rock stratum is brought influence.In order to improve the precision of surveying absolute depth; System deviation according to difference produces constantly with each rock stratum of being paid close attention to, is corrected to result of detection constantly at local noon; Because adopting multiple tracks surveys simultaneously; Between the required loaded down with trivial details correction simplified section for measuring point of pointwise was arranged when single-point was surveyed, or the system deviation correction between the measuring point square formation layout, and improved the order of accuarcy of proofreading and correct.This method; Be that the face of land that belongs to each measuring point is the zero point of investigation depth; Utilize the face of land relative altitude of each measuring point write down, the result of detection of each point is corrected to the same reference field of exploratory area known elevation height, further improve and survey the laterally fine degree of contrast of histogram.

The tenth step remote data processing center is carried out data processing

The 11 step remote data processing center is drawn result map

The 12 step remote data processing center is carried out the data contrast

In remote data processing center, geologic information and other the various physical prospecting data relevant according to the exploratory area are carried out the geologic structure contrast once more to surveying result map.When appearance is inconsistent between the data in comparison process; Repeat the processing procedure in the 7th step and the 8th step, result of detection is checked, find the cause and correct; What occur between the contrast of affirmation data on inspection is inconsistent; And the non-natural electromagnetic field changes the influence bring, still keeps original data corresponding state, makes the contrast of surveying result map and geologic structure obtain affirmation.

In order to improve detection quality and geologic interpretation level, the data contrast needs the dimensionless relative resistance rate (ρ with the rock stratum of being paid close attention in the result of detection after obtaining confirming _r) amount to the apparent resistivity that becomes to have dimension (ρ _a), in order to improve the effect of physical prospecting, at present, extensively having adopted multiple geophysical prospecting method comprehensive utilization and geologic interpretation at areal, the result of detection of therefore having ready conditions with other geophysical prospecting method compares, to obtain the effect of comprehensive utilization.

Claims

1. natural electromagnetic radiation sounding multichannel detection method is characterized in that the concrete steps of this method are:

The first step makes up detection system

A kind of natural electromagnetic radiation sounding multichannel detection method realizes that through a kind of multiple tracks detection system this detection system comprises: a plurality of detection subsystem and remote data processing center; Wherein, detection subsystem comprises: electric-field sensor, prime amplifier, post amplifier, double balanced mixer, narrowband intermediate frequency wave filter, accurate wave detector, feedback circuit, local signal generator, peak detector, valley wave detector, subtracter, totalizer, divider, A/D converter, D/A converter, marker generator and computing machine; The data that the ground location device is gathered and stored are transferred to remote data processing center through the networking after the computing machine pre-service;

Second step was confirmed the measuring point arrangement form

The measuring point arrangement form of each exploratory area detection subsystem comprises: the section that the section of measuring point is arranged, the square formation of measuring point is arranged and the sea is surveyed is arranged, and the concrete parameter of definite measuring point layout;

The section of measuring point is arranged:

When the measuring point number that is arranged along a straight line surpasses 5 measuring points; The section that promptly can be considered measuring point is arranged; Section is arranged along the pendage direction of estimating; Measuring point is decided according to the level of detail of concrete object of surveying and detection at interval, and measuring point is spaced apart 20 meters-50 meters, uses 6-12 tread sniffers to work simultaneously; Be used for the ore bed of estimating, the structure on stratum are tentatively surveyed; When section needs overtime, the terminal measuring point of section overlaps with the head end point position of its prolongation section, and it is different constantly because of surveying to be used for inspection, the system deviation between the section;

Before detection operations, the face of land relative altitude of each measuring point is measured; Because investigation depth is calculated from the face of land, need the relative altitude of each ground, road sniffer of record on the face of land,

The 5th step was obtained the moment of each same opening entry in road

In order to obtain the record that each ground, road sniffer synchronization begins; After each ground, road sniffer start; The operator utilizes marker generator when surveying; To each ground sniffer; Send fixed frequency signal; As each ground, road sniffer opening entry distinguishing mark constantly, and the moment of writing down each opening entry;

The 6th step utilized the ground location device to gather detection data

In order to receive near surface electric field vertical component

K＝Δ/∑.........................................；(3)

Investigation depth scope on the estimation relies on and regulates local signal generator institute output signal frequency, sets the frequency range of corresponding measured signal, chooses the frequency interval of discrete measured signal according to the level of detail of surveying; Local signal generator of every setting when manually-operated; Can be according to the difference of the centre frequency of local signal generator and narrowband intermediate frequency wave filter; Try to achieve frequency F and the corresponding Δ value and the K value of measured signal: in rectangular coordinate system, measured signal frequency F that each is discrete and corresponding Δ value or K value are depicted as F-Δ curve or F-K curve; By the standard of 6 db-losses as definite cutoff frequency; Try to achieve the cutoff frequency value Δ F that is associated with each maximum value and minimal value from F-Δ curve or F-K curve; Utilize following cutoff frequency formula, try to achieve the corresponding investigation depth h of getting, Δ F=(3.76 * 10 with Δ F ⁶)/σ h ², from the maximum value of F-Δ curve relative resistance rate (ρ with rock stratum in minimal value is tried to achieve corresponding depth range _r); At last, draw with represented as histograms and be convenient to the h-ρ that compares with graphic well log _rCurve abbreviates the detection histogram as; The F-K curve is identical with the purposes of F-Δ curve, is used to reduce the time dependent influence of natural electromagnetic radiation;

When surveying automatically, adopt built-in embedded system to carry out detection process control automatically, data acquisition and processing; By the frequency of operation of D/A converter control local signal generator, promptly corresponding investigation depth h, the output signal of accurate wave detector is directly transported to A/D converter; In the data of gathering, to V _PmaxAnd V _TminJudge, calculate Δ, ∑ value and K value, draw the h-ρ of F-Δ curve or F-K curve, each measuring point automatically _rCurve and comprehensive each measuring point h-ρ _rThe sectional view of curve;

The centralized stores of the 7th step detection data

The computing machine centralized stores is by data, exploratory area measuring point arrangenent diagram and the daily record of work of each ground sniffer transmission;

The quality check of the 8th step record

At first given to each ground sniffer; Each adjacent measuring point is surveyed histogrammic form and is laterally contrasted, when morphological differences is obvious, and the adjacent measuring point data of inspection Computer Storage; Check point position according to exploratory area measuring point arrangenent diagram, concrete condition when checking detection according to daily record of work; Once more to V _PmaxAnd V _TminJudge, and draw the detection histogram of each adjacent measuring point, get rid of the influence that natural electromagnetic field changing factor brings, make each adjacent measuring point survey the horizontal contrast of histogrammic form and obtain confirming;

The 9th step computing machine carries out the data pre-service

Computing machine carries out pre-service to each ground sniffer recorded data, and the pre-service content comprises: survey histogram according to each ground sniffer recorded data and each measuring point, i.e. the h-ρ that representes of represented as histograms _rCurve contrasts the detection histogram of all measuring points comprehensively, obtains the basic condition of exploratory area subsurface geologic structures; Because the vertical component of the natural electric field observed is to be superimposed upon atmospheric envelope ionization is formed owing to shined upon; Intensity up to 120 volts/rice; Cycle is about on the circadian vertical electric field, and observation is different constantly, and high-strength and long cycle vertical electric field makes the cycle of observation signal produce change; And in its correspondent frequency territory, produce frequency displacement, thereby the investigation depth and the thickness of rock stratum is brought influence; In order to improve the precision of surveying absolute depth, the system deviation according to difference produces constantly with each rock stratum of being paid close attention to, is corrected to result of detection constantly at local noon; Owing to the employing multiple tracks is surveyed simultaneously, between the required loaded down with trivial details correction simplified section for measuring point of pointwise was arranged when single-point was surveyed, or the system deviation correction between the measuring point square formation layout, improved the order of accuarcy of correction; This method; Be that the face of land that belongs to each measuring point is the zero point of investigation depth; Utilize the face of land relative altitude of each measuring point write down, the result of detection of each point is corrected to the same reference field of exploratory area known elevation height, further improve and survey the laterally fine degree of contrast of histogram;

The tenth step remote data processing center is carried out data processing

Computing machine utilizes network, gives remote data processing center with detection data pre-service result transmission, and remote data processing center is according to pre-service profiling as a result; Geologic information and other the various physical prospecting data relevant according to the exploratory area are carried out the geologic structure contrast to surveying result map, and comparing result is drawn result map after confirming;

The 11 step remote data processing center is drawn result map

Remote data processing center is drawn two-dimentional pseudo-colours sectional view and three-dimensional pseudo-colours rock stratum spatial distribution map respectively, to having the three-dimensional pseudo-colours rock stratum spatial distribution map of time parameter, draws corresponding multidimensional pseudo-colours map;

The 12 step remote data processing center is carried out the data contrast

In remote data processing center, geologic information and other the various physical prospecting data relevant according to the exploratory area are carried out the geologic structure contrast once more to surveying result map; When appearance is inconsistent between the data in comparison process; Repeat the processing procedure in the 7th step and the 8th step, result of detection is checked, find the cause and correct; What between above-mentioned inspection affirmation data, occur is inconsistent; And the non-natural electromagnetic field changes the influence bring, still keeps original data corresponding state, makes the contrast of surveying result map and geologic structure obtain affirmation;

In order to improve detection quality and geologic interpretation level, the data contrast needs the dimensionless relative resistance rate (ρ with the rock stratum of being paid close attention in the result of detection after obtaining confirming _r) amount to the apparent resistivity that becomes to have dimension (ρ _a) or resistivity (ρ); In order to improve the effect of physical prospecting, at present, extensively adopted multiple geophysical prospecting method comprehensive utilization and geologic interpretation at areal, the result of detection of therefore having ready conditions with other geophysical prospecting method compares, to obtain the effect of comprehensive utilization;

Other all geologic informations and physical prospecting data according to this area, same location, same depth range; To some rock stratum tabulation of being paid close attention to, in tabulation, indicate the top board degree of depth, thickness and the apparent resistivity (ρ of each rock stratum _a) or resistivity (ρ);

According to the detection result map of this area that remote data processing center obtained, same location, same depth range,, in tabulation, indicate the top board degree of depth, thickness and the relative resistance rate (ρ of each rock stratum to some rock stratum tabulation of being paid close attention to _r);

In two kinds of tabulations, find out the top board degree of depth, thickness and the approximating rock stratum of resistivity height; And with the relative resistance rate (ρ of some rock stratum of being paid close attention to _r) be converted into the apparent resistivity (ρ of dimension _a) or the respective value of resistivity (ρ);

After remote data processing center is carried out above-mentioned contrast, make some rock stratum of being paid close attention to obtain having the apparent resistivity (ρ of dimension _a) or resistivity (ρ); Although the resistivity with a kind of rock stratum still has the certain distributed scope, but still can be the rock stratum lithology that judgement pays close attention to reference data is provided, remedied the relative resistance rate (ρ in the result of detection _r) be the influence of nonlinear relationship with investigation depth, owing to adopt multiple tracks to survey, the horizontal contrast degree of result of detection is improved, thereby detection quality and geologic interpretation level are improved; Can be at the above-mentioned comparing result of application in a big way in exploratory area, thus large-area detection quality and geologic interpretation level are improved, and work efficiency also is improved significantly; Remote data processing center is grasped the work progress situation in each exploratory area at any time, and where necessary the work arrangements in exploratory area is proposed adjustment information.

2. a kind of natural electromagnetic radiation sounding multichannel detection method according to claim 1; The square formation arrangement form that it is characterized in that said measuring point is: the square formation of measuring point is made up of many horizontal sections and longitudinal profile; Measuring point interval and profile intervals are 20 meters-50 meters, use 6-12 tread sniffers to work simultaneously; Ore bed, stratal configuration are laterally being surveyed with space distribution longitudinally; Wherein have common measuring point and mutually perpendicular section; Be used to survey the rock stratum vergence direction and inclination angle, survey the rock stratum, deep under the native state of high temperature and high pressure; The direction of terrestrial stress and the space distribution of its amplitude and terrestrial stress space distribution over time, for earthquake forecasting research provides reference information; The scale of square formation is confirmed by the quantity of the ground location device that is adopted; The square formation of measuring point is along laterally or during longitudinal extension of square formation; The location overlap of the edge section of extension square formation and the edge section of former square formation, it is different constantly because of surveying to be used for inspection, the system deviation between each square formation.

3. a kind of natural electromagnetic radiation sounding multichannel detection method according to claim 1, the measuring point arrangement form when it is characterized in that surveying on the said sea is: keep measuring point at interval with floating hawser, the section that constitutes measuring point is arranged; Be used for ore bed, the stratal configuration estimated are tentatively surveyed; Adopt many parallel sections to arrange, to laterally surveying of ore bed, stratal configuration with space distribution longitudinally; Connection section with repeat station is set between each bar section, and it is different constantly because of surveying to be used for inspection, the system deviation between each section; The ground location device is fixed on the top of buoy; Be used to avoid sniffer to contact the sealing problem that seawater faces; Also since the conductivity of free space and seawater differ greatly, therefore, in the time of also can obtaining signal and under the sea, return free space; The benefit that electric field intensity is enhanced, the geographic position of measuring point is confirmed by Global Positioning System (GPS).

4. a kind of natural electromagnetic radiation sounding multichannel detection method according to claim 1; It is characterized in that said definite measuring point arrangement form; According to the geological condition in exploratory area and specific requirement, confirm that each exploratory area detection subsystem adopts square formation arrangement form and a kind of measuring point arrangement form in the section arrangement form that the sea is surveyed or the combination of said several kinds of measuring point arrangement forms of section arrangement form, the measuring point of measuring point to detection mission.