CN215375817U - Time-frequency electromagnetic method ground monitoring data acquisition device - Google Patents
Time-frequency electromagnetic method ground monitoring data acquisition device Download PDFInfo
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- CN215375817U CN215375817U CN202121596383.5U CN202121596383U CN215375817U CN 215375817 U CN215375817 U CN 215375817U CN 202121596383 U CN202121596383 U CN 202121596383U CN 215375817 U CN215375817 U CN 215375817U
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 title claims abstract description 24
- 239000002689 soil Substances 0.000 claims abstract description 26
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 15
- 238000010248 power generation Methods 0.000 claims abstract description 15
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 9
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- 238000012360 testing method Methods 0.000 description 4
- 230000005684 electric field Effects 0.000 description 3
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
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Abstract
The utility model provides a time-frequency electromagnetic method ground monitoring data acquisition device, which comprises a foundation soil layer, a transmitting end and a measuring net, wherein the measuring net comprises a plurality of receiving ends and measuring points; the transmitting end comprises a power generation vehicle, a power generation lead, an A field source and a B field source; the A field source and the B field source respectively comprise a first electrode pit, an aluminum plate, a transmitting line, a cable and a first signboard; an aluminum plate is arranged in the first electrode pit, and four cables are arranged in the transmitting route; according to the utility model, four cables are arranged in the transmitting route, so that the effect of reducing the line resistance is achieved, meanwhile, a plurality of first electrode pits dug in an A field source and a B field source are matched, an aluminum plate is buried in the first electrode pits, the power supply area is enlarged, the large-current transmitting is ensured, a plurality of first electrode pits are dug, the depth exceeds thirty centimeters, the resistance is reduced by taking measures, the grounding resistance is less than ohm, and the accuracy of ground monitoring data acquisition is ensured.
Description
Technical Field
The utility model relates to the technical field of ground monitoring, in particular to a time-frequency electromagnetic method ground monitoring data acquisition device.
Background
A time-frequency electromagnetic method is a new method appearing in the field of oil exploration, adopts a working mode similar to large-offset seismic exploration, arranges a long-wire high-power current source on the ground, excites a target layer by using variable-frequency square wave current, observes components of an electric field and a magnetic field on the ground, and simultaneously obtains depth measurement results of a time domain and a frequency domain. And through the processing of time domain and frequency domain signals, an earth electric model is accurately constructed, and the resistivity and polarizability abnormity of the exploration target is obtained.
Under the conditions of small topographic relief, small interference, simple geological structure and small depth of a horizontal well, positive relative amplitude abnormity and high resistivity abnormity can occur in the process of monitoring the hydraulic fracturing by using a time-frequency electromagnetic method, and the position and the depth of the abnormity are completely coincided with the depth of a perforation point and the depth of the horizontal well, which shows that the process of monitoring the hydraulic fracturing by using the time-frequency electromagnetic method is feasible;
however, when the time-frequency electromagnetic method is adopted to collect the ground monitoring data at present, some problems still exist:
when the time-frequency electromagnetic method is adopted for collecting the ground monitoring data, the cable of the transmitting end penetrates through the ground, however, when the cable penetrates through the ground and reaches the receiving end, a large amount of resistance interference exists midway, so that the resistance is increased, and the ground monitoring data collection accuracy is low.
SUMMERY OF THE UTILITY MODEL
In view of this, the embodiments of the present invention are intended to provide a time-frequency electromagnetic method ground monitoring data acquisition apparatus, so as to solve or alleviate the technical problems in the prior art, and at least provide a useful choice.
The technical scheme of the embodiment of the utility model is realized as follows: a ground monitoring data acquisition device adopting a time-frequency electromagnetic method comprises a foundation soil layer, a transmitting end and a measuring net, wherein the measuring net comprises a plurality of receiving ends and measuring points;
the transmitting end comprises a power generation vehicle, a power generation lead, an A field source and a B field source;
the A field source and the B field source respectively comprise a first electrode pit, an aluminum plate, a transmitting line, a cable and a first signboard;
an aluminum plate is arranged in the first electrode pit, and four cables are arranged in the transmitting route;
the power generation vehicle is electrically connected with the field A source and the field B source through power generation wires;
the receiving end comprises an acquisition station, a second electrode pit, a non-polarized electrode, a sodium-based soil layer and a second signboard;
the first electrode pit and the second electrode pit have a depth of thirty-five to forty centimeters;
and a sodium-based soil layer is filled in the second electrode pit.
In some embodiments: first electrode pits are uniformly formed in the A field source and the B field source.
In some embodiments: the emitting line is positioned in the foundation soil layer, and the distance between the upper surface of the emitting line and the upper surface of the foundation soil layer is thirty-five centimeters to forty centimeters.
In some embodiments: the measuring point is arranged on one side of the receiving end.
In some embodiments: the collecting station is installed on a foundation soil layer, the second electrode pit is arranged inside the foundation soil layer, and the non-polarized electrode is installed inside the second electrode pit.
In some embodiments: the second signboard is installed at one side of the second electrode pit.
In some embodiments: first signboards are arranged on one side, located on the launching route, of the surface of the foundation soil layer at equal intervals, and the distance between every two adjacent first signboards is fifty meters to one hundred meters.
Due to the adoption of the technical scheme, the embodiment of the utility model has the following advantages:
according to the utility model, four cables are arranged in the transmitting route, so that the effect of reducing the line resistance is achieved, meanwhile, a plurality of first electrode pits dug in an A field source and a B field source are matched, an aluminum plate is buried in the first electrode pits, the power supply area is enlarged, the large-current transmitting is ensured, a plurality of first electrode pits are dug, the depth exceeds thirty centimeters, the resistance is reduced by taking measures, the grounding resistance is less than ohm, and the accuracy of ground monitoring data acquisition is ensured.
The foregoing summary is provided for the purpose of description only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present invention will be readily apparent by reference to the drawings and following detailed description.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments or technical descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a block diagram of the present invention;
FIG. 2 is a block diagram of an A-field source according to the present invention;
FIG. 3 is a schematic view of the connection between the cable of the launching path and the foundation soil layer in the present invention;
FIG. 4 is a block diagram of a receiving end according to the present invention;
FIG. 5 is a schematic diagram of the non-polarized electrode of the present invention for collecting ground monitoring data.
Reference numerals: 1. a base soil layer; 10. a transmitting end; 11. a power generation car; 12. a power generating wire; 13. an A field source; 131. a first electrode pit; 132. an aluminum plate; 133. a transmission route; 134. a cable; 135. a first signboard; 14. a B field source; 20. measuring a net; 21. a receiving end; 211. a collection station; 212. a second electrode pit; 213. a non-polarizing electrode; 214. a sodium-based soil layer; 215. a second signboard; 22. and (6) measuring points.
Detailed Description
In the following, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
As shown in fig. 1-5, an embodiment of the present invention provides a time-frequency electromagnetic method ground monitoring data acquisition device, including a foundation layer 1, a transmitting end 10 and a measuring net 20, where the measuring net 20 includes a plurality of receiving ends 21 and measuring points 22;
the transmitting terminal 10 comprises a power generation vehicle 11, a power generation lead 12, an A field source 13 and a B field source 14;
the a field source 13 and the B field source 14 each include a first electrode pit 131, an aluminum plate 132, a transmission line 133, a cable 134, and a first signboard 135;
an aluminum plate 132 is arranged in the first electrode pit 131, and four cables 134 are arranged in the transmitting route 133;
the power generation vehicle 11 is electrically connected with an A field source 13 and a B field source 14 through power generation wires 12;
the receiving end 21 comprises a collecting station 211, a second electrode pit 212, a non-polarized electrode 213, a sodium-based soil layer 214 and a second signboard 215;
the depths of the first electrode pits 131 and the second electrode pits 212 are thirty-five to forty centimeters;
the inside of second electrode pit 212 is filled with sodium-based soil layer 214.
In one embodiment: first electrode pits 131 are uniformly formed in the A field source 13 and the B field source 14 and used for embedding an aluminum plate 132, so that the power supply area is enlarged, and large-current emission is ensured.
In one embodiment: the transmitting line 133 is located in the foundation layer 1, and the distance between the upper surface of the transmitting line 133 and the upper surface of the foundation layer 1 is thirty-five to forty centimeters, so that the four cables 134 in the transmitting line 133 are more than thirty centimeters away from the ground, and the measured data is ensured not to be influenced by ground environment factors.
In one embodiment: the measuring point 22 is disposed on one side of the receiving end 21 to ensure the complete coverage of the fractured zone.
In one embodiment: the collecting station 211 is arranged on the foundation soil layer 1, the second electrode pit 212 is arranged inside the foundation soil layer 1, and the non-polarized electrode 213 is arranged inside the second electrode pit 212; the non-polarizing electrode 213 measures the electric field component Ex through the electrode whose both ends of MN are grounded.
In one embodiment: the second signboard 215 is installed at one side of the second electrode pit 212; and determining the position of the second electrode pit 212 to ensure that the position of the non-polarized electrode 213 is unchanged in the construction process and the in-situ collection is carried out.
In one embodiment: first sign boards 135 are equidistantly arranged on one side of the surface of the foundation soil layer 1, which is positioned on the launching path 133, the distance between the adjacent first sign boards 135 is fifty to one hundred meters, a specially-assigned person should be kept to the patrol personnel in place when the launching path 133 passes through villages or areas with frequent activities of people and livestock, and a high-pressure danger warning sign is arranged on the first sign boards 135 to warn the passing pedestrians.
In this embodiment: the second electrode pit 212 of the non-polarized electrode 213 has a depth of 35cm, a length of 20cm and a width of 20cm, the slurry made of the sodium-based soil layer 214 is not less than 10cm, the electrode is in good contact with the slurry, and the grounding resistance of the non-polarized electrode 213 is not more than 2000 omega.
In this embodiment: the transmitting terminal 10 adopts the mode of deeply digging a first electrode pit 131, digging a plurality of first electrode pits 131, connecting a plurality of wires in parallel, reducing resistance by taking measures of multiple measures, ensuring that the grounding resistance is less than 10 ohms, and simultaneously laying four cables 134 along a transmitting route 133 to reduce the resistance, and digging a plurality of first electrode pits 131 at an A field source 13 and a B field source 14, wherein the distance between the first electrode pits 131 is 3m for burying an aluminum plate 132 underground, so that the power supply area is increased, and the large-current transmission is ensured.
In this embodiment: during measurement, the measuring points 22 are designed in the measuring group room, and on-site RTK accurate lofting is paid attention to, so that the measuring line direction, the measuring point positions and the electrode distances are guaranteed to be not poor; and (3) implementing line by line and point by point, burying the shielding line and the non-polarized motor 213 at one time, and corresponding the point positions and the instrument system to each other in the whole process, so that all interference factors are eliminated, and meaningful weak abnormity is obtained.
In order to ensure the quality of monitoring data and avoid fracturing vibration and well site humanistic interference, the data acquisition is carried out at night after the fracturing task is completed in the daytime. Under the condition that the number of the existing acquisition stations 211 is not enough to simultaneously cover the whole measurement area, a rolling acquisition mode of multiple transmission and multiple simultaneous reception groups is adopted. And after data acquisition is finished, indoor Wifi wireless data transmission is performed.
In this embodiment: the quality control measures are adopted for acquiring the electromagnetic weak abnormal signals generated by the fracturing fluid as follows:
(1) non-polarized electrode 213 is adopted as the electrode, and the depth of first electrode pit 131 and second electrode pit 212 is more than 30 cm;
(2) collecting a background field before water injection fracturing, carrying out data collection once for each stage of fracturing, not replacing a non-polarized electrode 213 and a collection station 211 in the whole fracturing monitoring process, and watering a second electrode pit 212 every day;
(3) all cables 134 are buried with sand and are not exposed to air;
(4) the repeated emission times of the square wave signals of each frequency are not less than 30 times;
(5) the emission current is not less than 60A, and the same current is emitted each time.
And ensure that:
1) before working, calibrating a receiving instrument;
2) the corresponding relation between the instrument and the measuring point/measuring line is strictly recorded, and the same measuring point is ensured to be measured by using the same instrument when the front measuring point and the rear measuring point are measured for several times;
3) the voltage difference of the 213 pairs of the non-polarized electrodes is less than 2mV, and the range of each pair of the non-polarized electrodes is recorded;
4) the second electrode pit 212 is at least 30cm deep, is properly widened, is filled with the sodium-based soil layer 214, and ensures that the grounding conditions are consistent during different time measurement;
5) the position of the strictly non-polarized electrode 213 is unchanged; marking a second signboard 215;
6) testing the emission times and the frequency table of each frequency in an experiment; ensuring that a sufficiently high signal-to-noise ratio and secondary field abnormality can be identified, carrying out indoor simulation and field test in two stages, particularly paying attention to the fact that the quality factor of each frequency of a low-frequency section is ensured to be small enough, the amplitude of a low-frequency signal is ensured, ensuring the signal-to-noise ratio of the low frequency, only receiving an acquisition station 211 after the field test is finished, not polarizing an electrode 213 and not recovering a cable 134, carrying out measurement again after the field test is placed for one day, and comparing the results of multiple measurements; preparing for changing the receiving and transmitting distance after once acquisition;
7) the emission current is kept unchanged during measurement at different time intervals;
8) the emission grounding condition is processed, the aluminum plate 132 is embedded, and the current is ensured to be large enough.
9) Three-dimensional forward modeling, namely simulating different point distances of 20m and 50m, and performing forward modeling by using the resistivity value of the low-resistance volume after fracturing water injection as 2 times or 5 times of the original low resistance;
10) the amplitude of the change of the amplitude before and after fracturing is at least more than 5 times of the quality factor, so that the amplitude can be distinguished.
In this embodiment: when the non-polarized electrodes 213 are paired, the non-polarized electrodes 213 are placed in a basin and left for a period of time, and the range between each pair of electrodes is measured after the non-polarized electrodes 213 are stabilized.
The utility model is in operation: the transmitting end 10 is a horizontal finite length ground wire source formed by four copper cables 134 connected in parallel, an advanced high-power transmitter which can reach 200kW is adopted, the voltage is automatically adjusted within the range of 150-2000V according to the change condition of the ground resistance of the transmitting end 10, a series of excitation currents are sent to the ground according to different frequencies, the receiving end 21 measures the electric field component Ex through electrodes with two end points of MN grounded, the four cables 134 are arranged in a transmitting route 133 to achieve the effect of reducing the line resistance, meanwhile, a plurality of first electrode pits 131 dug in an A field source 13 and a B field source 14 are matched, aluminum plates 132 are buried in the first electrode pits 131, the power supply area is enlarged, large-current transmitting is ensured, the first electrode pits 131 are dug more, the depth exceeds thirty centimeters, the resistance is reduced more, the ground resistance is ensured to be smaller than 10 ohms, and the accuracy of ground monitoring data acquisition is ensured.
The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various changes or substitutions within the technical scope of the present invention, and these should be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (7)
1. The utility model provides a time frequency electromagnetic method ground monitoring data acquisition device, includes basic soil layer (1), transmitting terminal (10) and surveys net (20), its characterized in that: the measuring net (20) comprises a plurality of receiving ends (21) and measuring points (22);
the transmitting end (10) comprises a power generation vehicle (11), a power generation lead (12), an A field source (13) and a B field source (14);
the A field source (13) and the B field source (14) respectively comprise a first electrode pit (131), an aluminum plate (132), a transmitting line (133), a cable (134) and a first sign board (135);
an aluminum plate (132) is arranged in the first electrode pit (131), and four cables (134) are arranged in the transmitting route (133);
the power generation car (11) is electrically connected with the A field source (13) and the B field source (14) through power generation leads (12);
the receiving end (21) comprises a collecting station (211), a second electrode pit (212), a non-polarized electrode (213), a sodium-based soil layer (214) and a second signboard (215);
the first (131) and second (212) electrode pits have a depth of thirty-five to forty centimeters;
the inside of the second electrode pit (212) is filled with a sodium-based soil layer (214).
2. The time-frequency electromagnetic method ground monitoring data acquisition device according to claim 1, characterized in that: first electrode pits (131) are uniformly formed in the A field source (13) and the B field source (14).
3. The time-frequency electromagnetic method ground monitoring data acquisition device according to claim 1, characterized in that: the emission line (133) is positioned in the foundation soil layer (1), and the distance between the upper surface of the emission line (133) and the upper surface of the foundation soil layer (1) is thirty-five to forty centimeters.
4. The time-frequency electromagnetic method ground monitoring data acquisition device according to claim 1, characterized in that: the measuring point (22) is arranged on one side of the receiving end (21).
5. The time-frequency electromagnetic method ground monitoring data acquisition device according to claim 1, characterized in that: the collecting station (211) is installed on a foundation soil layer (1), the second electrode pit (212) is arranged inside the foundation soil layer (1), and the non-polarized electrode (213) is installed inside the second electrode pit (212).
6. The time-frequency electromagnetic method ground monitoring data acquisition device according to claim 1, characterized in that: the second signboard (215) is installed at one side of the second electrode pit (212).
7. The time-frequency electromagnetic method ground monitoring data acquisition device according to claim 1, characterized in that: first sign boards (135) are installed on one side of the surface of the foundation layer (1) on the launching route (133) at equal intervals, and the distance between every two adjacent first sign boards (135) is fifty meters to one hundred meters.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121596383.5U CN215375817U (en) | 2021-07-14 | 2021-07-14 | Time-frequency electromagnetic method ground monitoring data acquisition device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121596383.5U CN215375817U (en) | 2021-07-14 | 2021-07-14 | Time-frequency electromagnetic method ground monitoring data acquisition device |
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| Publication Number | Publication Date |
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| CN215375817U true CN215375817U (en) | 2021-12-31 |
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| CN202121596383.5U Expired - Fee Related CN215375817U (en) | 2021-07-14 | 2021-07-14 | Time-frequency electromagnetic method ground monitoring data acquisition device |
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2021
- 2021-07-14 CN CN202121596383.5U patent/CN215375817U/en not_active Expired - Fee Related
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Granted publication date: 20211231 |