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GD-10 Application Cave Survey

1. Test purpose

The GD-10 electric instrument was used to conduct geological disasters investigation in a certain area of ​​Jiujiang County to identify the development of earth caves, karsts and faults in Quaternary area.

Test parameters

The high-density electrical method to GD-10 multi-function electrical system as the host, the electrode device using Winner α device. GD-10 instrument spacing factor of 1, the maximum spacing factor of 39, the electrode spacing of 5m, profile length of 600 meters, a total of 120 ways to measure the layout.

3. Work Area Overview

The geophysical prospecting area of ​​the topography is mainly erosive hills terrain, the overall trend of the mountain to the north east.

According to the regional geological data, combined with other geological survey data, the stratigraphic lithologies in the survey area include Quaternary silty clay and limestone.

4. Work area geophysical characteristics

According to the regional geological data and field measurements, the geotechnical properties of the site are relatively complex. The resistivity of Quaternary is generally n × 10Ω · M. The resistivity of underlying bedrock is generally in the range of n × 102 ~ n × 103Ω · M. Quaternary soil resistivity values ​​vary greatly by their own composition and degree of water content, generally loose high water content, low resistivity value, and vice versa. The resistivity value of bedrock is relatively high. When the fractured zone is developed and contains some water, the resistivity value obviously decreases, and there is a certain electrical difference with the surrounding rock.

5. Data Analysis and Interpretation

Field measured data will be transmitted to the computer, through special processing software, field data measured point mutation processing, terrain correction and other operations into the map.

Before the measurement, we must first conduct an electrode grounding resistance test, grounding resistance are normal, begin data acquisition and measurement.

According to the high-density resistivity chromatogram, there is a relatively low-resistivity anomaly with a resistivity of 6-42.4Ω · M at a depth of 9.47-32 meters at the point of 150-165 meters, which is interpreted as a cave. At the point At 355-380 m, there is a relatively low-resistivity zone, interpreted as a karst fissure zone; at depths of 480-505 at depths of 5-14.5 m at depths of 515-525 at depths The resistivity is relatively low at 6-14.5 meters below ground, explaining the inferred karst loose zone.

In order to validate the survey results of GD-10, borehole verification was carried out in the 150-165m area. The results show that this area is indeed a karst cave development zone, and the depth and scale of GD-10 delineation and the actual drilling data show The results are basically consistent.



A foundation of a temple depth survey

1. Test purpose

The GD-10 high-density electrical method instrument is used to investigate the foundation of a nearby temple. The 2D high-density resistivity profile test method is mainly used to test the profile of the ground surface around the tower. Since high-density exploration depth is relatively shallow, but high resolution, the observed resistivity change interface to detect the substrate interface, the depth of the substrate.

Test parameters

In this test, a total of 6 high-density measurement lines are arranged, using a wennerα device with a distance of 1 meter and a total of 48 channels.

3 test results analysis

This data is processed using res2dinv inversion software

According to the inversion results, we can see that there is a clear boundary between high and low resistance at the depth of 1.5m, suggesting that this area is the base of the temple. Low resistance for the Quaternary. GD10 can accurately divide the foundation structure of the temple foundation and clarify the depth of the basement.

Leakage detection of dam tailings in a tailing pond

1. Test purpose

The work area is mainly 1 # tailings ponds and their surrounding ore mines and solid waste sites, the study of the surrounding leaking situation, the detection of pre-dam, earth dam and other anti-seepage projects are intact, whether it can effectively prevent the seepage of wastewater Leakage and aging areas where leakage may occur; identify the scope of the area where the seepage has occurred, determine the width and depth of the seepage, and delineate the target area for the leakage so as to provide the basis for the next environmental protection project. The means of exploration mainly for high-density electrical measurement, into the instrument for the production of our GD-10 high-density resistivity measurement system.

Test parameters

The high-density electrical measurement for the # 1 tailings pond and the surrounding area has been leaking six sections laid; peripheral ore pile layout of a section; two solid waste sites each laying a total of 9 profile lines laid. Geophysical prospecting lines are laid out in the principle of vertical stratigraphic strike, structural zone and fractured karst development zone. RTM and fast static observation are used to locate the measuring point. The measuring device uses Wenner α. Electrode pitch 2-3m, the total number of arranged electrodes determined according to the site, the detection depth greater than 45m. Before the measurement, we must first conduct an electrode grounding resistance test, grounding resistance are normal, begin data acquisition and measurement.

3. Data processing and interpretation

G1 line:

According to the high-density resistivity chromatogram analysis, the survey line is located on the dam. In the past, there was a leakage situation in the anomaly ① and reinforcement in the later stage. From this result, the apparent resistivity polar point is below 20 ohm , Speculated that there may still be leaks.

The low resistivity zone in the anomalous zone ② is strip-like with a steeper dip angle, with apparent resistivity of 20-50.

G2 line:

Based on the high-density resistivity chromatogram, the survey line is located on the upper lobe of the dam with a spacing of about 3 meters from the G1 line. The abnormal zone ① corresponds to the abnormal position ① of the G1 section, and is presumed to be the same leaking zone. Leakage area has increased, indicating that the water leakage belt along the downward trend has expanded.

G4 line:

Analysis of the resistivity chromatogram by high-density electrical method, there is a low resistance in the No. 1 area, which is presumed to be a water-conducting channel.

The anomalous area of ​​No. 2 is presumed to be a water leakage area with water accumulation on the surface and a water reservoir on the side. It is suspected that the water leakage at the bottom of the reservoir is presumed to be a fissure, and tends to be near north and south and westwards.

There is a ditch on the surface of the No. 3 area, and the direction of the ditches at this location is basically the same with that of the survey line, suggesting that the anomaly is caused by the ditch.

G5 line:













1. 测试目的


2. 测试场址及布置









3. 数据结果







本次工作是用于对比GD-10电法仪和AGI电法仪测试性能及精度等,施作时沿着滑移区布设了1条测线。测试选用Wenner α、Schlumberger以及Dipole-dipole装置。电极间距为5m,总道数为36道。在测量前,首先要进行电极接地电阻检测,接地电阻均正常后,开始进行数据采集。

3. 数据处理与结论

本次高密度电阻率对比测试,布设1条测线,数据处理采用AGI的EarthImager 2D反演软件,对比情况如下。

Wenner α装置对比反演图(a)GD10电法系统(b)AGI高密度电法仪


Dipole-dipole对比反演图(a) GD10电法系统(b)AGI高密度电法仪

根据反演结果可知,GD10电法仪的 Dipole-dipole脚本增加了测量点数,加深了对深层资料的解析,通过对于小信号资料点的优化处理,在测量总长度及分辨率相同的情况下,可以比AGI多往下探测20m左右。














The inversion results show that there are low resistivity zones (anomalous zones) with apparent resistivities of about 30 to 37.6Ω • m in the region from 26m to 28m in the depth of about 0.6 inner zone. At the same time, low resistivity zones (anomalous zones) with apparent resistivities of about 15 to 30 Ω • m appear in the 38m to 60m zones with an inner depth of about 0.7. Based on the analysis of the electrical structure of the test site, the two abnormal site test sites were buried in the model. Because the test results and the actual situation is basically the same.





































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