While-drilling advanced forecasting apparent resistivity measuring system and method

Abstract

The invention relates to a while-drilling advanced forecasting apparent resistivity measuring system and method. The while-drilling advanced forecasting apparent resistivity measuring system comprises a magnetic-dipole antenna installed in a drilling rig, a plurality of receiving electrodes distributed in surrounding rocks around a drill hole and an on-site main machine connected with the multiple receiving electrodes. The magnetic-dipole antenna is used for automatically outputting pulse electromagnetic waves in real time in the process of advancing in the drill hole along with the drilling rig and forming induced electromagnetic fields in the different-depth surrounding rocks around the drill hole; the receiving electrodes are used for real-time receiving of electric signals generated in the different-depth surrounding rocks around the drill hole by the induced electromagnetic fields; and the main machine is used for processing the electric signals received by the multiple receiving electrodes and obtaining the apparent resistivity of the different-depth surrounding rocks around the drill hole. According to the while-drilling advanced forecasting apparent resistivity measuring system and method, detection precision of geophysical exploration can be improved, the control range of advanced hole exploration can be increased as well, detection efficiency of advanced hole exploration can be improved, and the quantity of the arranged drill holes is reduced.

Description

technical field [0001] The invention relates to the technical field of geophysical electrical prospecting and drilling, in particular to an apparent resistivity measurement system and method for advanced prediction while drilling. Background technique [0002] Advanced detection is mainly to detect the direction of tunnel and roadway excavation by direct or indirect methods at the head of the tunnel, to detect whether there are harmful geological structures or rich water bodies and water guide channels ahead, and to provide detailed detection data for safe tunneling. At present, the direct method used for advanced detection of coal mines is the drilling method, and the indirect method is the geophysical method; although the drilling method is relatively reliable for the drilling results of a single borehole, the drilling results are only valid for a single borehole, and it is impossible to detect from point to area As a result, the drilling methods in key detection areas can...

AI Technical Summary

Problems solved by technology

Except for the drilling advance water detection method above, other geophysical methods are all advanced detection methods for tunnels, roadways or working faces. Various metal facilities such as I-beam support, bolt support, and conveyor belt support have a great influence on the observation results. At the same time, the site construction design, data observation, and result analysis are complex, and the detection parameters are single, resulting in multiple solutions.

Moreover, the advanced drilling water exploration method is to put the detection probe into the borehole for detection after the borehole is formed, which is similar to the logging technology on the ground. It is impossible to carry out the drilling advanced water exploration work after the borehole collapses. , the construction is basically carried out by means of push rod measurement; the push rod is limited by its own weight and the friction of the hole wall, generally the depth is less than 40 meters, and this method cannot overcome the problem of excessive grounding resistance, resulting in the supply current Weak or even no effective signal can be measured, and the detection effect is useless

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