A ground-roadway transient electromagnetic detection method in multi-layer goaf

Abstract

The invention discloses a transient electromagnetic detection method for ground-roadway of a multi-layer goaf. The transient electromagnetic detection method for the ground-roadway of the multi-layer goaf mainly includes data gathering and data processing. The concrete steps include that paving a large emitting coil on the ground to emit electromagnetic signals to the underground, distributing three-component receiving probes at upper and lower gate roadways, cutting holes, connection roadways and the like of the roadway of the underground working surface to gather data, and transmitting the data to a general console desk on the ground through an underground data gathering station and a data transmission system; processing the data, and obtaining the analysis result through the primary processing and apparent resistivity conversion for the data, image display of the data and data comparison. The transient electromagnetic detection method for the ground-roadway of the multi-layer goaf is capable of identifying the water layer position of the multi-layer goaf of the whole mine lot without blind area in a high resolution, realizing dynamic monitoring and effectively dividing the boundaries of each goaf in the mine lot in the vertical direction and horizontal direction to provide guarantee for the safety production of coal; the transient electromagnetic detection method for the ground-roadway of the multi-layer goaf greatly improves the resolution capability of the multi-layer goaf of the mine and realizes careful exploration.

Description

technical field [0001] The invention relates to a transient electromagnetic detection method, in particular to a multi-layer goaf ground-roadway transient electromagnetic detection method. Background technique [0002] The accumulation of water in the goaf is one of the main reasons for the large water inrush accidents in coal mines in my country. Coal measures are formed during the oscillation process of the earth's crust, which is dominated by subsidence movement, and are mostly distributed in layers. Generally, there are multiple layers of mineable coal seams in my country's coal fields from top to bottom. The mined-out area formed after the upper coal seam is mined becomes a water catchment area, which is dominated by static reserves and has high water pressure. Once it is dug through, it will be fierce and destructive, which will easily cause mass casualties and damage the adjacent working face and the lower coal seam. Mining poses a safety hazard. [0003] In recent ...

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Problems solved by technology

For direct current exploration, it is more prominent that a certain length of the survey line is required. If the length of the roadway that can be constructed is limited, it cannot meet the requirements of the exploration depth; second, when the rock formation is broken and dry, the contact between the electrode and the rock formation will often bring The third is that when the working face is wide, it is easy to form a detection blind zone in the middle part above the roof of the working face

Mine audio and electrical perspective has achieved good geological results in the detection of the water-conducting structure inside the roof and floor of the coal mining face and the water-richness of the aquifer. However, it is also difficult to arrange electrodes in the actual detection. The construction must be the work of preparation for mining. or the area where there are two troughs (penetration distance<350m), the spatial position of hydrological anomalous geological bodies within 100m height (or depth) of the roof between the two troughs is mainly explored. There are still unresolved theoretical and practical issues. Problems, such as selection of frequency range, determination of detection depth, functional relationship between frequency and depth, etc.

[0007] Mine transient electromagnetic method is an underground detection method developed in recent years. Because of its convenient and quick construction and sensitivity to water-bearing bodies, it has become one of the main methods of mine hydrographic exploration. However, its detection depth is limited. When the position is far away, the ideal detection depth cannot be achieved. At the same time, although the detection of different azimuths can be achieved by changing the direction of the coil plane, there is still a certain detection blind area in the direction of the top plate.

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