CN1040439A - The electromagnetic apparatus of stratal configuration imaging - Google Patents

Abstract

A kind of device that detects unusually and analyze that is used for geological formations, this device comprise a transmitter that links to each other with the resonant tank antenna, antenna in geological formations vertical ground to certain orientation.Transmitter is launched continuous ripple arrowband FM signal on the medium-frequency band of about 300～800KHz.One continuous wave intermediate-frequency receiver can receive the signal of transmitter, and with one in geological formations vertical ground the resonant tank antenna of certain orientation is linked to each other.This receiver comprises the device of the field intensity that is used for measuring and write down received signal, and an area of computer aided treating apparatus, is used for the explanation results record data.

Description

The electromagnetic apparatus of stratal configuration imaging

The instrument of universal relation of the present invention geologic anomaly in the detection of coal seam, in particular, this part invention is about utilizing continuous wave intermediate frequency radio imaging technique and area of computer aided composition technology to draw the instrument of the unusual figure in coal seam that radiation produces.

The coal seam of stratification or coal bed are because all geological mechanisms have all become shape.Which floor compresses the difference of degree on every side, can cause fracture, complications and the protuberance in coal seam.Ancient times, the river brushed away the coal on the coal bed, stayed sand and rock deposition.This deposition also is exactly that the river course sandy soil wash away, and can cause erosion and weak top.This coal seam deformation and rock deposition all are the physical obstacles of mining.In coal mining industries, extensively adopt two kinds of underground coal mining technology.A kind of house column type that cries is mined continuously, and this extraction system can be walked around many obstacles and open

Continuous Mining Technology is taken less and only need a small amount of manpower.For example, only need during exploitation eight people open class Three usually.Yet, exploit per tour continuously and can only produce about 300 tons of coals.The another kind of technology that extensively adopts is broadwall.The longwell technology is very effective when the even coal bed of exploitation, and throughput rate on average can reach 1500 tons of per tour.

In the U.S., mining safety and health control office require to adopt the retrusive longwell, and do not wish to adopt the protrusive longwell.But in Europe, the protrusive longwell is used a lot.The retrusive longwell is towards main roadway direction exploitation, and the protrusive longwell is to leave main roadway direction exploitation.When retreating longwell, foundation to use Continuous Mining Technology.From main tunnel, with meet at right angles direction and of main tunnel at the either side in longwell exploiting field, can exploit out two tunnel routes.These tunnel routes, lane and tail tunnel headed by each, the length that prolongs into the longwell exploiting field.The end in the longwell district, pick one crosscut between first tunnel and tail tunnel.The wall that faces toward the crosscut in main tunnel is the face of longwell, and just along this face driving, its head is just pointing to main tunnel to longwall shearer.When longwell moves forward, just collapse in the top of digging out the top, district.To stay the stopper of unminding coal in the end of excavating, to support the top of top, main tunnel.

Under the situation that has long mining area to exploit, because the high yield of longwell mining, adopting broadwall is favourable economically.A typical longwell exploiting field can comprise 500,000 to 1,000,000 tons of coals.The initial outlay of longwall mining and to set up expense all very high, the average millions of dollar of cost of equipment.Setting up of longwell minimumly takes 30 days, every day class Three, per tour 12 to ten four-players.Therefore, it is very big to set up expense, and will obtain the low price production interests of longwell method, and needing the coal seam is uniformly, to keep long-term production.Coal seam unusual, for example fracture, erosion, mineral deposit alternation sum run into vein, and longwell production is stopped ahead of time.In many examples, run into unusual after, longwell equipment will change the drill bit of " hard " into, perhaps blows with explosive, this may destroy equipment and the miner is in danger.Therefore, if before exploitation, can detect and analyze the coal seam unusually, production practice just can be planned to such an extent that to make production cost be minimum so.If can survey a long continuous coal seam, so just can adopt longwell technology cheaply.If find to have the obstacle of longwell mining, so, mining engineering department can adopt continuous mining to walk around these obstacles, perhaps for example adopts and washes away or the explosion way, these are washed out unusually or explodes.

For the geologic prospecting that potential productive value colliery is arranged, known have a several different methods.These methods have adopted various technology.Satellite imaging and photography use for the data of appearing the whole world for ORGANISATIONAL ATTRIBUTES man.Yet, because this data can only provide a general picture, can exploit in the decision coal seam, this data do not play effect.Surface layer and the macroscopic view of appearing are reconnoitred (making an on-the-spot survey), according to sand smeller's existing knowledge, can forecast the characteristic on stratum.The earthquake on the face of land and electromagnetic wave propagation method comprise oil and natural gas for economic ore deposit, in geophysical survey, also extensively adopt, yet, these microcosmic prospecting techniques, also unreliable on the detailed structure in investigation coal seam.

In order to draw about the unusual useful data in coal seam, what adopt at present is the interior seismic method of ore bed that various microcosmic are reconnoitred.In Europe, a kind of technology that is developing is arranged, it is from 16 ground point source explosions, listens to 120 groups of jugs, and every group has 36 jugs, and the geological data Computer Processing of gained, result can be found fracture.Up to now, this method need be placed explosive and be needed to install quite long electric wire at 5 feet intervals.Seismic method is not mainly want advancing longwall method to use retreating longwall method.In addition, do not prove that also this method has the unusual ability of husky bed that solves, for part erosion and unessential little unusual, this method can not be surveyed the situation of top or bottom rock especially.Appear the face of land in one's mind based on geomagnetism method, the ability of seeing the earth's crust is also arranged with Controlling Source.This method is useful when surveying the main faults of ore bed, but can not solve detailed ore bed structure.

Drilling well is useful to surveying the longwell obstacle.Bore 10 * 12 holes of 600 feet in the minery, so that to the coal seam sampling, yet the shortcoming of this method is the sub-fraction of topped obstacle only.Because topped area is limited, so the ore bed that this method may exist between surveying and solve boring and holing is otiose when unusual.Remain the reliable sources of coal information from face of land test core and well-logging.The rock core sample provides the useful data of describing the stratum.Well-logging can detect near the composition the boring.But if the distance between drilling well and the drilling well surpasses about 50 feet, the unusual of ore bed all can not be surveyed and solve to used well-logging method at present.It is unusual that horizontal drilling in the ore bed can detect ore bed, but it is subjected to the restriction of coverage equally with vertical probing.In addition, horizontal drilling is very expensive, and one ton of coal of average every production will be changed 20 cents.

Once study good several electromagnetic techniques, attempted to provide a kind of geophysical method that can see inside, coal seam.Common and synthetic Radar Technology is reported in the literature to some extent.Because the frequency of radar is very high, it is exceedingly useful near the geologic structure the research boring.Yet, spy for deep layer, in order to maintain the resolution of usefulness, just need very high emissive power, this is along with the distance in the ore bed decays rapidly because of high-frequency signal.Therefore, present radar method can not be seen the depths of ore bed.

(" CROSS BOREHOLE ELECTROMAGNETIC PROBING TO LOCATE HIGH-CONTRAST ANOMALIES " GEOPHYSICS " measured height and contrast unusual cross borehole electromagnetic surveying " in the article of R.J.LYTLE, VOL., 44, № .10, OCT.1979) and " computerized geophysical tomography art " (" COPUTERIZED GEOPHYSICAL TOMOGRAPHY " PROC.IEEE, VOL., 67, № .7, JULY 1979) illustrated with the method for continuous wave (CW) signal to the coal seam imaging.His method only is the chromatographic imaging between near two holes.The method of LYT1E is all restricted on distance and resolution, because be limited to the space, makes measurement can only utilize the probe of using in the boring.In order to satisfy tomographic requirement, LYTLE adopts higher frequency, and therefore, operating distance is very short.In addition, have been found that the conductivity of the conductivity of rock much larger than coal.In the place that conductivity (contrast) differs greatly, the chromatographic imaging algorithm will be dispersed, and can not restrain, and the result can not get image.

By the A.D.LITTLE of a company of U.S. mineral bureau leader's a research, studied the propagation of continuous wave intermediate-freuqncy signal in the coal seam.(result who delivers on APR.1976) is about electromagnetic utilization for VOL. II, NO.4, but the purpose in order to communicate by letter just at " RADIO SCIENCE " for A.G.EMSLIE and R.L.LAGACE.In addition, in used radio wave propagation equation, may be also wrong.At the BrP № of KAISER .1, in 018,188, revealed the method for utilizing high frequency radio wave to test various media.In the EPO of SCHLUMBERGER company limited patented claim № .0105801, revealed a kind of well-logging method and instrument.This method be not be used for deep layer penetrate with imaging ， Only be near conductivity and the specific inductive capacity that is used for measuring the boring.

Other electromagnetic technique method has operating distance and resolution problem too.Technology is not in the past all recognized and is had a 300-800KH in the coal seam _zTransmission container.Therefore, there is not a kind of prior art can draw remote, high-resolution geologic anomaly image.

Simple declaration of the present invention

Therefore, an object of the present invention is to provide the instrument of facing the unusual imaging in coal seam in the heading with ground, its operating distance is enough to the exploiting field imaging of whole longwell.

Further purpose of the present invention provides the instrument of the unusual imaging in coal seam, and its resolution is enough to detect fracture, all and erosion, the river course sandy soil of part wash away, vein and staggered mineral deposit.

Further aim of the present invention is to utilize the ground imaging of fracture direction to reduce production costs, and provides the suitable trend of longwell.

Another purpose of the present invention is to determine walking backward of exploiting field, utilizes that imaging reduces production costs in the lane in longwell exploiting field.

A further object of the invention is to alleviate or eliminate because the danger that unexpected geologic anomaly constitutes the miner.

Another object of the present invention is to measure the height in coal seam.

Further purpose of the present invention is to provide detailed coal seam image in the front of longwell.

Further purpose of the present invention is the slump of prediction top layer.

Further purpose of the present invention is to verify unusual that prediction arrives with the signal strength measurement device.

In brief, the embodiment that the present invention recommends comprises a continuous wave MF transmitter, it has the ability of frequency modulation, and is furnished with the annular orientation antenna, a continuous wave intermediate-frequency receiver is furnished with the annular orientation antenna, and can accurately measure and the amplitude of recorder signal and the phase shift that transmits, and data processing equipment, it produces the expression figure in coal seam according to the raw data that obtains.Transmitter and receiver all is of portable form, and is designed to two kinds of structures: a kind of is the garden cylindricality, and as a probe, so that be inserted into downwards in the boring in coal seam, another kind is of portable form, and can be carried in the tunnel, is suitable for using in the heading.

Here the embodiment of Tui Jianing has utilized continuous wave intermediate frequency (ME) signal, with less output power, obtains the unusual full resolution pricture of coal geology.The scope of intermediate frequency is commonly defined as about 300KH _zTo about 3MHZ.Because the coal seam is all limit by the conductivity rock different with coal up and down, under some signal frequency, electromagnetic energy can propagate into far distance.This transmission window, or be the coal seam pattern can encourage with the tuning tours antenna of implementing in novel, makes the MF signal transmit hundreds of rice in the coal seam.The anomaly sxtructure in coal seam has caused a zone that its electrical quantity is different with coal.Utilize the different of coal and anomaly sxtructure electrical quantity, just provide the formation method here.This difference has changed the propagation constant of electric wave at this place, thereby analyzes the electric wave that this place's far-end is received, just can determine the texture of coal seam between the transmitter and receiver.

Continuous instrument and tomography instrument all adopt frequency modulation (FM) signal of arrowband in the intermediate frequency tunnel, receiving instrument then uses phaselocked loop (PLL) technology to detect and measure the signal of receiving, the input threshold of phaselocked loop receiver can be lower than noise, therefore can improve operating distance.At the electrical quantity of coal seam and anomaly sxtructure the place of suitable difference is arranged, can adopt the continuous imaging method.And when the difference of electrical quantity hour, available tomography art.If carry out many-sided space measurement, then can improve the resolution of tomography instrument, therefore overcome the restriction of inherent distance by radar.

Need a drilling well plan when adopting downward boring method, intermediate-freuqncy signal can be propagated in the coal seam between the boring.In the method, many holes will be bored in the both sides, coal seam.Transmitter probe and receiver probe just are inserted in the boring of both sides, coal seam respectively, and the decay of measuring-signal in the coal seam.In a series of borings, the position of conversion transmitter and receiver can draw a series of data points.Measure signal attenuation, path loss and phase shift and compare, just can determine to have in the coal seam not unusual with calculated value.In addition, utilize the area of computer aided imaging technique to get the expression figure of coal output layer to these data reconstruction one-tenth figure.Detect when unusual, be on the tangent plane in original plan two holes additionally again bore some holes and determine unusual position to obtain further reading.Imaging technique in the lane, coal seam, except instruments such as transmitter and receiver being placed on the first lane and the tail lane of tested heading, it is all similar with the ground imaging technique that other carries out mode.

In addition, this instrument can also be used for the trend of detection of coal seam fire to improve the security of mining.Fire in the coal seam has influenced the conductivity in coal seam, therefore as being detected out unusually.With detection method in the lane, coal seam, known where fire is arranged, just can control spreading of it.In another kind is used,, just can be set up communication to falling into the miner who is stranded so if the miner who goes into the well is equipped with little receiver or transceiver.Bored a hole by the sunken miner's of being stranded suspicious area, the instrument of using in the patchhole just can encourage the coal seam, communicates by letter thereby fall into the miner who is stranded with quilt.

Advantage of the present invention is to obtain the unusual expression image in coal seam with imaging technique.

Another advantage of the present invention is to have selected suitable mining way, and it is minimum that production cost is dropped to.

The present invention has an advantage Shi Only again with least equipment and minimum boring number, just can draw image.

The present invention has an advantage Shi Only just energy imaging of lower emissive power again.

It is by the detection to the workplace geologic anomaly that the present invention has an advantage again, can increase the security of coal mining.

Other has an advantage is can detect effluent road sandy soil with instrument of the present invention to wash away the part erosion that causes.

Also having an advantage is to make the situation of top/bed rock stone with instrument of the present invention.

Another advantage of the present invention is can fall into the miner who is stranded with this equipment and quilt to communicate by letter, and therefore, has increased the security of mining.

It is the trend that can determine coal bed fire with instrument of the present invention that an advantage is arranged again.

It is to measure the height in coal seam that the present invention has an advantage again.

It is just can draw detailed coal seam image in the front of longwell that the present invention has an advantage again.

The present invention also have an advantage be can the prediction top layer slump.

It is to verify unusual in the coal seam that the present invention also has an advantage.

The people who has general technical ability aspect the present technique, after the embodiment that has read to describe in detail, can know clearlyer to these and other purpose and advantage of the present invention undoubtedly for those with various accompanying drawings.

Accompanying drawing

Fig. 1 is the oblique view that is used for the present invention's lane, coal seam inner receiver;

Fig. 2 is the oblique view that is used for transmitter in the present invention's the lane, coal seam;

Fig. 3 is the sectional view that is used for the probe used in the present invention boring;

Fig. 3 a is equipped with the oblique view that makes probe be centered in the probe of using in the boring of the frame placed in the middle in the boring;

Fig. 4 is the hole block scheme of inner receiver and transmitter probe component of Fig. 3;

Fig. 5 is desirable coal face, has shown the position of Fig. 2 transmitter and Fig. 1 receiver when adopting tomography in the heading;

Fig. 6 is desirable coal face, has shown near several borings that the coal seam is and the layout of hole interior probe and surface facility;

Fig. 7 is desirable coal seam top view, has shown top layer rock formation method;

Fig. 8 is desirable coal face, has shown a plurality of instrument investigation methods;

Fig. 9 is desirable coal face, has shown in the lane, coal seam to merge the investigation method of using with the interior instrument of boring, and vertical drilling and horizontal drilling are wherein arranged;

Figure 10 verifies the method unusual in the coal seam and the desirable top view of instrument; And

Figure 11 is the sketch of the embodiment of probe in the another kind of boring of the present invention.

Fig. 1 has shown portability continuous wave intermediate frequency (CW MF) receiver that the interior tomography of heading is used.Tomography is just as used herein to be a generic noun, is used for representing a kind of magnetography method of intermediate frequency (MF) signal to texture of coal seam.Formation method can be used also can be without the tomography algorithm.Receiver is with figure 10 expression, and it is a single conversion super heterodyne type receiver, and frequency range is 300 to 800KHZ tunable, and is increment with 5KHZ.Receiver is designed to it can measure the field intensity that transmits automatically, and the field intensity that records is transformed into digital signal, uses in order to next step data processing.Receiver 10 comprises tuning tours antenna 11, distance record keyboard 12, magnetic tape recorder 13 and field intensity indicator 14.

Fig. 2 represents a continuous wave MF transmitter, and it is with figure 20 signs.Transmitter 20 is category-B transmitters, and frequency range 300 to 800KHZ is tunable, and is increment with 5KHZ.The output power of transmitter 20 is 20 watts.This is enough under 520KHZ to provide at least 1550 feet of operating distances according to the difference of medium.Transmitter 20 also has a tuning tours antenna 21.Transmitter antenna 21 and receiver antenna 11 for example can be made up of in two flexible resilient plastic sheets the wire clamp of a fixing turn, and plastic sheet is fixed on the circle.Plastic sheet can be by temporary transient bending, so that by narrow place, its material for example is the flexible plastics of commercially available " LEXAN " trade mark.The profile of transmitter 20 and receiver 10 as following said, be suitable for using in the lane, and their block scheme as shown in Figure 4.Receiver 10 and transmitter 20 are except the ability that continuous wave signal is arranged, and transmitter 20 also designs to such an extent that can produce and launch narrow-band frequency modulation (FM) signal, and receiver 10 designs to such an extent that can receive arrowband FM signal and energy demodulation sort signal.This function can be used to measure phase shift, so that provide the additional useful data to geology abnormality detection and imaging.For this measurement, transmitter 20 must be to reference signal of receiver 10 emissions.This signal is to transmit by light transmitting fiber 22 as shown in Figure 5.Light transmitting fiber 22 is bonded to receiver 10 by plug 24 lotus roots, and is bonded to transmitter 20 by plug 26 lotus roots.

Imaging need enter near the coal seam in the tunnel.The situation of not digging as yet for first lane and tail lane, for example in protrusive longwell situation, the perhaps quite shallow and goodish situation of ground probing characteristic for coal bed can adopt the ground surface imaging of probe in the boring.Fig. 3 has represented the general shape of probe in the boring, and marks with figure 30.Probe 30 is garden cylindricalitys, so that be inserted in the standard-sized boring.Probe 30 comprises a column-style shell 37, about 2 inches of diameter.Garden post shell 37 can be made with various materials, preferably selects the material of the saturating radio radiation of fiberglass and so in this enforcement is novel for use.Rotatable support 40 is housed in the garden post shell 37.Support 40 is solid garden posts, and cannelure 42 is arranged, and two is plane 43.On each plane 43 the modular circuit plate is housed, comprises antenna direction control 44, modulator-demodular unit 45 and receiver 46 or transmitter 47, this is decided by that this probe has receiver ability or transmitter capabilities.In pod 42, be placed with the lead of tuning tours antenna 48.Because the directivity of tuning annular antenna radio transmission, so the device of mechanical rotation all must be housed the antenna of receiver probe and transmitter probe, this two antenna can be adjusted on the same plane, and this is to drive support 40 rotations by motor 49 to finish in garden post shell 37.Motor 49 is fixed on the proximal end of garden post shell 37, with support 40 is arranged being connected of machinery, makes support 40 can do 360 ° of rotations completely in shell 37.In this enforcement was novel, the power of CD-ROM drive motor 49 was supplied with by 6 cadmium cells 50, and nickel-cadmium battery 50 is fixed on the near-end of support 40, just in time below motor 49.Garden post shell 37 is sealed with block 51 at far-end, seals with block 52 at near-end.4 core sockets of standard are housed, so that socket cable 54 on the block 52.By cable 54 probe 30 and uphole equipment are linked up, and transmit the data that imaging is used by it.The ground-based electronic equipment of match-drill inner receiver 30 usefulness comprises signal strength display/register, modulator-demodular unit and the radio transmitter/receiver that transmits reference signal when probe is operated in the FM pattern between two probes.

In order to guarantee that probe is placed in the boring with one heart, shown in Fig. 3 a, to adorn a location placed in the middle clip on the probe.This of locating clip placed in the middle has individual near-end block 55, and this block can be attached on the probe near-end block 52.Block 55 has a center pit, and cable 54 passes center pit and draws.Sleeve 56 tightly is enclosed within the far-end of probe 30 shells 37.Block 55 and sleeve 56 are equipped with 3 to 4 bands 57.Band 57 is made by tough and tensile resilient material, for example makes with the Thin Stainless Steel bar, and the band middle part curves the arc of outside protrusion, be convenient to contact with the boring inwall, band 57 is quite pliable and tough, can make probe 30 remain on boring central authorities, and makes probe be easy to slide in boring.

Equipment and ground investigation method in the boring also can be used in exploitation, and for example when finding new coal seam is arranged below the mine coal coal seam, in this case, instrument and method in the boring are still adopted in coal seam below also can being bored into from present coal seam.

Present embodiment all plans to adopt the component of modular for instrument 10 and 20 in probe 30 and the lane, coal seam in the boring.Can reduce cost and be convenient to maintenance like this.Fig. 4 is the general block scheme of modular component.

Table 1 is the inventory of a modular unit, and table 2 is matrix representations, and instrument 10 and 20 composition in the probe 30 and tunnel are described in each boring.

Table 1

Modular unit

The A1 receiver

The A3 transmitter

A10 c ³Modulator-demodular unit

A13 display/register

B6 Nicd battery

Tuning tours antenna

Annex

The C1 formula of holing

C2 is portable

Table 2 is formed matrix

Instrument A1 A3 A10A13 B6 C1 C2

Boring formula (30)

Transmitter 1111

Receiver 1111

Ground 11

In the tunnel (10 or 20)

Transmitter 20 111

Receiver 10 1111

Some examples of device specifications all show table 3 to 7 in.Table 3 has been listed the general work parameter of system.Table 4 and table 5 have been listed the technical indicator of transmitter and receiver.Table 6 explanation transmitter and receiver antenna characteristics, table 7 has provided the index of modulator-demodular unit.

Table 3

Systematic technical indicator

The signal emission:

Form A W and arrowband FM

Frequency range 300 is to 800KHZ

Tuning 5KHZ increment

Peak frequency deviation 100HZ

Modulation:

Frequency range 200HZ

Environment:

Working temperature-40 is ℃ to 80 ℃

Pop one's head in 500 pounds/square inch

Table 4

Transmitter

The complementary category-B of form

Module declaration A3

Frequency range 300 is to 800KHZ

Tuning 5KHZ increment

20 watts of output powers

Flatness ± 1/2DB

Rf load impedance 50 Europe and 200 Europe

Voltage standing wave ratio (VSWR) VSWR maximum 3: 1

Mixing oscillator 10.7MHZ

Signal oscillator 100HZ

9 to 15 volts of direct currents of operating supply voltage

Required electric current 3.5 peaces

Plug

Pattern MOLEX

Output power 2

VCC 1

Ground wire 1

Fiber optic cables (reference) 1

1

Table 5

Receiver

The monotropic superhet that changes of form

Module declaration A1

Frequency range 300 is to 800KHZ

Tuning 5KHZ increment

IF frequency 10.7MHZ

Source impedance 50 Europe

Sensitivity 0.1 microvolt (for the 12DB signal to noise ratio (S/N ratio))

Selectivity

3DB bandwidth 200HZ(minimum)

70DB bandwidth 1KHZ

Audio frequency

Whistle suppresses the 50DB(minimum)

No whistle suppresses 30DB(100UV)

Load 8 Europe

Frequency response

3DB 10、70、100HZ

Voltage table

Pattern and transmitter local oscillator are synchronous

0 to 360 ° of range

Table 6

Antenna

The tuning tours antenna of form

Frequency range 300 is to 800KHZ

The number of turns 11

Magnetic moment

Boring formula 8ATM ²@20 watt

Portable 8ATM ²@20 watt

Point to

The form fluxgate compass

(boring formula)

Table 7

C ³Modulator-demodular unit

Form MANCHESTER sign indicating number form

16 bit codes

Function

Electric power on/off

Aerial position ± 30 instruction

In the occasion that can not be directly adjacent to the coal seam, can be inserted into probe 30 in the boring in a series of borings of coal seam periphery and carry out the ground surface imaging, this method is as shown in Figure 6.

The coal seam imaging is based on the different conductivity of coal and anomaly sxtructure.The conductivity of rock is than the big several magnitude of conductivity of coal.The vertical duction of tuning loop transmit antenna produces horizontal magnetic field H φ and vertical electric field Ez.On the height of coal seam, these two field intensity almost are constants.On away from the antenna radial distance, this two field intensity is according to exponential decay, and attenuation rate is by effective attenuation constant (α) decision, and this constant is determined by the specific inductive capacity of loss in coal and the rock and coal.Thickness of coal seam reduces, the coal seam conductivity increases and relative dielectric constant when increasing, and this attenuation rate is estimated and can be increased.When rock conductivity increased, this attenuation rate will reduce.Attenuation rate also depends on the frequency that transmits and the water cut in coal seam.EMSLIE and LAGACE two people's measurement result shows that the attenuation rate of coal is about the 4DB/100 foot.These facts have constituted the basis of coal seam continuous imaging method.

Tuning tours antenna motivates the signal of low-loss nature of coal seam pattern according to establish an equation down (1):

（1）Hφ＝

f（rαhε _cε _rб _cб _r）

Wherein M is the magnetic moment of emitting antenna, and r is the distance of emitting antenna to receiving antenna, and α is an attenuation constant, and h is the coal seam height, ε _cAnd ε _rRespectively be the permittivity of coal seam and rock, б _cAnd б _rIt respectively is the conductivity of coal seam and rock.Magnetic moment M itself depends on emissive power P ₀And bandwidth B _w, it can be expressed as equation (2):

（2）M＝C $\sqrt{\frac{\mathrm{Po}}{\mathrm{Bw}}}$

More than two equations show that together tuning tours antenna will motivate the magnetic moment of nature of coal seam pattern, and, just can reach distance farthest if maximum magnetic moment can be provided.Narrow bandwidth also can be improved the sensitivity and the operating distance of receiver.Receiver sensitivity S when receiver intermediate frequency (IF) signal to noise ratio (S/N ratio) is 10dB ¹⁰ _DBProvide by (3) formula:

（3）S ¹⁰ _dB＝-164+10log ₁₀BW _IF+10log ₁₀NF

BW wherein _IFBe the intermediate-frequency bandwidth of signal, NF is the noise figure of receiver.

(3) formula shows that sensitivity will increase when bandwidth reduces.(1), the result of (2) and (3) formula shows that for the geological exploration instrument continuous wave intermediate frequency (MF) signal is best.This is because narrow-band signal will be propagated with minimum attenuation rate (equation 3) and the highest magnetic moment (equation 1 and 2) in the coal seam.The result can make the operating distance of instrument for maximum under certain output power.

Formation method depends on the comparison of signal intensity of calculating and the signal intensity of being measured by CW, MF instrument.And the signal intensity that above analysis is calculated will help the understanding to this method.For imaging method being provided a datum readings, available above-mentioned (1) formula is calculated the signal intensity of wishing acquisition in the specific coal seam.In order to accomplish this point, can measure each parameter to coal seam undetermined, substitution as a result (1) formula that will measure then.

The signal of propagating is to receive at the remote receiver place.Because the increase of coal seam " effectively " conductivity or the minimizing of coal seam height, along the approach that unusual coal seam is arranged, electromagnetic wave propagation can be subjected to the effect than the high attenuation rate.Therefore, compare the level of many received signals, can detect unusual on the approach.In addition, the refractive index of intermediate frequency radio signal changes in pure coal slowly, so signal is basically along rectilinear propagation.Propagation in the coal seam is parallel plane transverse electromagnetic wave (TEM) line mode substantially, is that electric field is vertical in the coal seam, plane on border at the rock up and down high with conductivity, and magnetic field is level.In the picture rock this coal seam unusually, its refractive index is different from the refractive index of coal, therefore, signal pathway can deflect away from bigger number of degrees.Narrow-band frequency modulation (FM) signal can be measured this approach loss, surveys unusual second method thereby provide.At last, the FM signal also can be pointed out existence unusual in the coal seam along the phase shift of route of transmission.

When needing high resolving power, tomography is more welcome than continuous imaging.Tomography has adopted the minimum frequency of attenuation rate and many-sided space measurement, and the result has improved resolution.On all directions of transmitter and receiver, measure attenuation rate, go to analyze the data point of gained again with the area of computer aided formation method, just can draw a unusual expression figure.

For the resolution that obtains, the distance between the transmitter and receiver should be greater than λ _c/ 2, wherein λ c is the wavelength of signal in the coal seam.For the 520KHZ transmission frequency of present embodiment, the signal wavelength in the coal seam is 97.7 meters.This makes minimum distance of separation is 15.56 meters.

Fig. 5 has shown chromatography imaging method in the heading, thereby will adopt the receiver 10 and the transmitter 20 that can carry in the tunnel, and carries out according to making resolution become maximum mode.Motivate the horizontal component ofmagnetic field (H of nature of coal seam pattern on the frequency that the tuning tours antenna 21 of transmitter 20 is selected in advance in 300 to 800KHZ _φ), make under given power output and provide maximum field intensity.The tuning tours antenna 11 of receiver adjust to transmitter antenna 21 on same plane, make the field intensity that receives become maximum.In order to obtain maximum resolution, the distance of separation of this two instrument is greater than 15.56 meters.In the present embodiment, the coal seam is that 600 feet (200 meters) are wide, and therefore enough distance of separations are arranged.As seen from Figure 5, if rock/egyptian bermuda 74 is arranged, this piece rock/egyptian bermuda 74 will be as a decay that the influential quality of radio wave propagation is caused transmission signals in the coal seam 70.Again because chromatography imaging method has adopted the signal frequency of minimum attenuation rate to reduce the output power of transmitter, so do not wish to have continuous electric conductor to exist in first tunnel and place, tail tunnel.This electric conductor can produce secondary magnetic field, thereby has disturbed the measurement of received signal level.In order to draw enough resolution in the exploration of tomography in the lane, should measure and collect data at diverse location.This step can be finished like this, promptly to each transmitter site in the first tunnel 78, (is appointed as X on each ad-hoc location in tail tunnel 76 ₀, X ₁... X _n) carry out the measurement of a series of received signal intensity.Equally, in first tunnel 78, transmitter 20 is placed on a series of certain location (is appointed as Y ₀, Y ₁... Y _n) and receiver 10 is placed on the relevant position in tail tunnel 76.In the tunnel, on each receiver location, all to come the coordinate position of recorder machine with record keyboard 12 with respect to transmitter.These coordinates all change into digital signal and deposit in the magnetic tape recorder together with the received signal value that records.Therefore when these data of reconstruct, the signal that records can be proofreaied and correct according to the change of transmitter and receiver relative position.The longitudinal separation of transmitter and receiver position is decided by the resolution of required image.The signal data that the result receives is deposited in the magnetic tape cassette 13 of receiver 10 after all being transformed into digital form, and general-purpose computers tomography algorithm is analyzed.This area of computer aided imaging algorithm will provide the detailed image of texture of coal seam.Computer-generated data also can comprise the printing that coal seam parameter (electric different rate, components of coal ash etc.) is printed and the numerical tape of the visual terminal of the computing machine that is used to mine.

The uphole equipment that is based on ground, coal seam surface imaging that Fig. 6 represents.With figure 80 representatives, can be seen in the coal seam, having a tomography 82 to exist by the coal seam of imaging.When adopting the ground imaging method, bore many holes 84 along the border in longwell exploiting field according to border exploration scheme.In the present embodiment, imaging can be planned with the probing of 10 borings in two adjacent longwell exploiting fields of 1200 feet beam overalls and 6000 feet long.The coal seam that this probing plan can detect in the exploiting field is unusual.If in an exploiting field, found a kind of tomography, just need to formulate a convergent search plan and go to determine its trend.This search plan is exactly to bore some borings of dividing equally again to determine the position of tomography in the border of determining tomography.It is similar putting the interior formation method of ground, coal seam mode that surface imaging carried out and heading.Bore a series of holes around the border in longwell exploiting field after, just probe 30 is inserted in the boring 84 up to the degree of depth in coal seam, this degree of depth has been known when boring sample.Fig. 6 has shown a kind of tomography of perpendicular displacement, and the result is that coal seam one end is darker than the other end.Because signal transmits through coal, not necessarily has the same degree of depth with transmitter probe 30 so be put into the receiver probe 30 of the coal seam degree of depth.Probe 30 in the boring comprises receiver probe and transmitter probe, is inserted in two relative borings 84.Utilize the motor 49 of probe 30 proximal ends in the boring, can adjust to same plane to Receiver And Transmitter antenna segment 48.The sensing of antenna decides by terrestrial contr 85 and controls, and 85 of control modules comprise remote measurement and opertaing device and a modulator-demodular unit.These unit and probe opertaing device and cable etc. all are contained in the trailer 86.The transmission of continuous wave FM intermediate frequency (CWMF) is to be undertaken by the same mode of formation method in the heading, and measures attenuation rate and/or phase shift.In each boring 84, with receiver pop one's head in 30 and transmitter probe 30 repeat this process.

The method of this ground survey also can be taken the ground lower surface to and do.This situation just appears when the coal seam below will surveying mined bed.So the end in existing coal seam, just become ground, and can hole thereon and survey following coal seam.Probe 30 in the boring still inserts in the hole of being bored, and measures then and reads according to normal ground location mode.

Analyze the continuous data of gained then, see the place that whether occurs decaying and increase.These places are exactly breakdown zone or other geologic anomaly zone.If the hole that is bored is abundant, so just can analyze these data with the computer-aided tomography imaging technique, and the same result who draws image with method in the lane, coal seam.

In addition, utilize the continuous coverage of continuous wave midband frequency can determine the characteristic on the end or top.The continuous coverage of this method and boring downwards is similar, 30 is placed on the top, coal seam but will pop one's head in Receiver And Transmitter when surveying the top layer situation, when surveying the bottom situation they is placed on the bottom.So propagate in the nigh rock of signal, signal attenuation is promptly measured.Can make the classification of rock and the situation of top or bottom like this.The rock crown characteristic also can decide in the following method; Promptly inner receiver 10 transmitters 20 in tunnel are placed on the very approaching place in tail tunnel and first tunnel 76 and 78, for example at interval about 25 feet, and with the back side and or restructing algorithm draw the thickness map of a width of cloth constant attenuation rate.Fig. 7 has illustrated a kind of method that obtains rock crown situation map picture in the tunnel 100 of exploiting, and this tunnel is to be between the existing tunnel 76 and 78.Receiver 10 is placed on the (X of series of points place in the tunnel 76 ₀, X ₁... X _n), 20 in transmitter is placed on the (Y of series of points place in the tunnel 78 ₀, Y ₁... Y _n), tunnel 100 is then between tunnel 76 and 78.Send an intermediate-freuqncy signal to receiver 10 from transmitter 20, just can measure attenuation rate, and the available back side reaches or the data of restructing algorithm analysis result.In order to improve the image of gained, the distance between the instrument position can shorten, for example 25 feet or shorter.Must notice that this method can be used between existing tunnel 76 and 78 100 imagings of single tunnel, also can be to 100 imagings of a plurality of tunnels.

Fig. 8 has illustrated the detection method that adopts single transmitter 20 and many receivers 10 in coal seam 70.This method has been quickened the acquisition of desired data, equally can be with single receiver 10 and many transmitters 20 or many receivers 10 and many transmitters 20.

For some specific purpose, also can utilize the many variations that reach downward bore detecting technology in the lane, coal seam.As shown in Figure 9, in the cross borehole detection method in the boring probe 30 can with tunnel inner receiver 10 and or transmitter 20 uses together, like this can be to the high-resolution image of unusual acquisition of existence in solid coal seam 102 in side, tunnel of exploiting.The also available back side of result's data restructing algorithm reaches or the chromatography algorithm is analyzed.

Fig. 9 also illustrates along a kind of method of level workings internal drilling 104 direction detection coal seam height.This method still adopts the cross borehole method, and with transmitter 20 in the tunnel and the probe 30 that is inserted in the drilling hole type in the horizontal drilling 104, boring 104 is perpendicular to transmitter exploration line A.Receiver probe 30 laterally moves in boring 104, for transmitter site Y ₀, Y ₁Y _nIn each position, probe 30 reads signal attenuation at diverse location.After having analyzed the figure of attenuation rate, just can make along the coal seam height of boring 104 to instrument displacement in the horizontal drilling 104.Yet this method is intended for use coal seam 70, this coal seam had the tunnel 76 that is pre-existing in and 78 or tunnel 100 can place instrument 10 or 20 in the lane, when adopting this method, can also be inserted into probe 10 in a series of borings 108, these boring positions are on a line perpendicular to boring 104.Fig. 9 also illustrates parallel probing method in a kind of lane, and it can be to vertically coal seam 70 imagings between the boring 110 of two levels.Boring formula probe 30 is inserted in the boring 110, and is the same with all other investigation methods, draw a series of readings on each position of transmitter and receiver.A kind of distortion of this method is to get out lateral aperture 110 and horizontal lateral aperture 104 longitudinally, and radiowave just transmits on the diagonal line of boring 104 and 110.As all methods, also can use one of instrument in the vertical boring and the instrument that moves horizontally or both together.Here can note, utilize modern directional drilling technology, can get out hole in the lane of level, therefore further expand the scope of prospecting by boring method with ground drill.Boring 110 and or 104 can in coal seam 70, on several different height, spudding in.Investigation method all can be used for the imaging to collapsing in above-mentioned any lane, coal seam in the method exploitation of collapsing.

In order to last any investigation method measure unusual, can be confirmed direct signal and reflected signal more once.As shown in figure 10, put a transmitter in the coal seam 70, it can be instrument 20 or the interior instrument 30 of boring in the lane, and it is to unusual 74 emission continuous wave MF signals.Again a receiver is placed on the transmitter next door, it can be instrument 10 or the interior probe 30 of boring in the lane, is used for receiving the signal that reflects from unusual 74.The signal that comes from transmitter or receiver by tours antenna 111 emissions, runs into unusually 74 through first interface of directional coupler 112 then, and a part of signal reflex is returned.The signal that reflects passes through second interface of antenna 111 approach axis coupling mechanisms 112, and has compared the power of power that sends signal and the signal that reflects in coupling mechanism 112.Increase reflective power on the power that unusual 74 existence will reflect in coal seam 70.

In bank 70, in case found unusually, can improve like this influence of broadwall, exactly longwell is divided into several sections.Avoid this unusually such as first section, second section to unusual driving, in the working direction of unusual either side perpendicular to longwell, utilizes Continuous Mining Technology to exploit out and adopts the servant quarters district and prepare the room district.Whole longwell continuation driving enters up to second portion adopts the servant quarters district, and when arriving this, this part has just been adopted and has prepared exploitation and prepare the room district.Simultaneously, the first of longwell continues driving, and and the second portion of exceptions area far-end be associated in together again.Another kind of method of not interrupting broadwall is to make unusually with means known to break.Such as, wash away with the mud of high pressure or the rosin of high-expansion, perhaps use common explosion means etc.

To being deeper than 1700 feet boring, very time-consuming expensive during boring, and it is also high to add the cost that sheath changes.If do not add sheath, drilling rod takes out back boring and then can be plugged.For this boring, can adopt the new type (as shown in figure 11) of the another kind enforcement of probe 30.This class probe 120 mainly comprise tours antenna 42 ', motor 49 ' with antenna 42 ' mechanically be associated in, and can make antenna 42 ' rotate around Z-axis.Voltage level Calibration Circuit 121 and the cable 122 that links with power supply and control device 123.The power supply on ground and control module 123 comprise transmitter with and/or receiver circuit, be used for transmitting to tours antenna 48 ' or from tours antenna 48 ' received signal.Power supply and information signal all 123 are conducted to probe 120 from the unit, and the information signal of receive is still sent unit 123 back to by cable 122.Voltage level Calibration Circuit 121 produces an accurate signal level, is used for demarcating from antenna to control device 123 whole signal pathways.After the probing scheme was finished, probe 120 can be stayed a very long time in the boring, when needing available it.Probe 120 also can comprise password lockout circuit 124, can prevent that so non-units concerned from removing to use this probe 120, and typical case is that probe is inserted in the boring by plastic tube.Perhaps directly insert through drilling rod.Plastic tube or drilling rod are taken back probe 120 away and are just stayed in the boring.

Though this invention illustrates with the embodiment that is recommended here, will be appreciated that and can not be construed to a kind of restriction to this revealing.For those people who is familiar with this gate technique, after the content of having read originally to reveal, can make many variations and modification undoubtedly.Therefore, plan here is construed to appended claim and comprises all variations and the modification that falls in true spirit of the present invention and the scope.

Claims (12)

1, survey and analyze the instrument of geologic anomaly, it is characterized in that it comprises:

One cover boring transmitter, it has a tuning tours antenna, in order to vertical orientation in ore bed, this Antenna+Transmitter electrically is coupled, and mechanically be coupled with a drive unit, thereby antenna can be rotated around a Z-axis, said transmitter is launched continuous wave arrowband FM signal on the medium-frequency band of 300KHz to 800KHz, a modulator-demodular unit that is coupled with said transmitter and cable unit is so that be connected said transmitter with the control device on ground, said ground control unit comprises the device of control antenna direction, transmitter also comprises an elongated probe and a locking device, with with said transmitter, antenna, drive unit and modulator-demodular unit encapsulate

One cover boring receiver, it has a tuning tours antenna, in order to vertical orientation in said ore bed, this antenna and continuous wave intermediate-frequency receiver electrically are coupled, this receiver can receive the signal by the transmitter emission, this antenna also mechanically is coupled with a drive unit, thereby antenna can be rotated around a Z-axis, said receiver comprises to be measured and pen recorder, in order to the data of measuring and record is most, the feature that comprises received signal, a modulator-demodular unit that is coupled with a said receiver and a cable unit is so that be connected this receiver with Ground analysis and control device, said Ground analysis and control device comprise the device of control antenna direction, and said receiver also comprises an elongated probe and a locking device, with with said receiver, antenna, drive unit, and modulator-demodular unit encapsulates

An area of computer aided treating apparatus, to receive, to handle and explain said record data, said record data are stored on the magnetic-based storage media by said Ground analysis and control device, so that analyzed by this area of computer aided treating apparatus after a while.

2, the described instrument of claim 1, it is characterized in that, said ground control unit comprises a modulator-demodular unit, a power output-controlling device and an antenna direction control device, and said Ground analysis and control device comprise a modulator-demodular unit and an antenna direction control device.

3, the described instrument of claim 1 is characterized in that, said IF-FRE scope is 400 to 600KHz.

4, the described instrument of claim 1 is characterized in that also comprising a reference signal out connector that is coupled to said transmitter, so that directly launch the FM reference signal thus,

An input connector that is coupled to said receiver, so as directly to receive said FM reference signal and

A reference signal transmission device so that said reference signal out connector and said reference signal input connector are coupled, thereby can be transmitted a reference signal between them.

5, the described instrument of claim 4 is characterized in that, said reference signal transmission device comprises a surface orientation antenna, and this antenna and said reference signal out connector are coupled, and be suitable for transmitting said FM reference signal and

One ground-plane antenna, this antenna and said reference signal input connector and said Ground analysis device are coupled, and are suitable for receiving said FM reference signal.

6, the described instrument of claim 4 is characterized in that, said reference signal transmission device comprises a cable.

7, the described instrument of claim 1 is characterized in that, said transmitter antenna and receiver antenna are installed in the place that is far apart transmitter and receiver.

8, the described instrument of claim 1 is characterized in that, the tuning tours antenna of said transmitter and receiver comprises the first and second deformable plastic tapes of mutual fastening respectively, and in an annular, with lead multi-turn kinking, thereby is clamped to therebetween.

9, the described instrument of claim 1 is characterized in that further comprising:

A reference signal output plug, it and transmitter are coupled, and directly transmit FM with reference to letter through it,

A reference signal input plug, the coupling of it and receiver is used for directly receiving said FM reference signal, and

A reference signal transmission device, it makes said reference signal output plug and the coupling of said reference signal input plug, thereby transmits reference signal betwixt by it.

10, the described instrument of claim 9 is characterized in that said reference signal transmission device comprises a cable.

11, a kind of instrument of surveying and analyzing geologic anomaly is characterized in that it comprises:

First terrestrial contr that contains a transmitter and first control device, said transmitter is suitable for the continuous wave arrowband FM signal of transmit frequency range between 300HKz to 800KHz, said first ground control unit is suitable for providing electric power and information signal and reception electric power and the information signal from a transmitter to a transmitter

One contains the first insertable tuning tours antenna, so that it is inserted in the boring, said first can insert antenna comprises a bracing or strutting arrangement and first drive unit that is coupled with it, can insert the rotation of day wire-wound one Z-axis so that drive said first,

One and said first can be inserted the first voltage level Correction circuit that antenna electrically is coupled, so as supply surely the number of be sure oing level proofread and correct from said first and can insert antenna to the signal path of said first control device,

First cable unit, so that can insert antenna and first terrestrial contr electrically is coupled with said first,

Second terrestrial contr, this unit comprises that one is suitable for receiving receiver and the second control device from the said continuous wave arrowband FM signal of said transmitter, said receiver comprises that also a measurement and pen recorder are to measure and to write down most data that received signal comprises characteristics of signals, said second control device is suitable for providing electric power and information signal and reception electric power and information signal from a receiver to a receiver

One comprises that second can insert tuning tours antenna so that be inserted in the receiver of boring, and said second can insert antenna comprises a bracing or strutting arrangement and second drive unit that is coupled with it, drive and rotate so that will said second can insert antenna around a Z-axis,

One and said second can be inserted the second voltage level Correction circuit that antenna electrically is coupled, so as to this antenna provision surely the number of be sure oing level with proofread and correct from said second can insert antenna to the signal path of said second control device and

Second cable unit is so that can insert antenna and second terrestrial contr is coupled with said second.

12, the described instrument of claim 11 is characterized in that further comprising one first encode seal lock circuit, and it and said motor, first drive unit, said first Correction circuit and said transmitter and control device are coupled,

One second encode seal lock circuit, it and said second drive unit, said second Correction circuit and said receiver and control device are coupled.

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