Figure 2 shows the curves of the difference between models electromagnetic response with
goaf present and the background field.
Goaf gas modeling techniques to aximize methane capture from surface gob wells.
To detect the spatial distribution of the
goaf and estimate the water quantity, MTEM was adopted with the YCS360 Electromagnetic System (as shown in Figure 5).
The coal
goaf area is a long-term relatively closed, dark, and humid environment.
Mining with Narrow Coal Pillar and Limited Thickness Extraction to Control the Surface Fissures in the Surrounding Area of
Goaf. The ground surface of the shallow coal seam mining face will generate mining-induced fissures [24].
(106.) Co-benefits are those benefits that are not the direct
goafOverlying rock masses hang in the
goaf for a certain time and then collapse (or slowly descend), loading with their weight worked-out strata bedrock.
Preliminary analysis showed that the accident was triggered by a gas explosion on the
goaf, or the deserted part of the mine already cleared of minerals, Xinhua quoted the municipal government of Chongqing as saying.
Currently, the fully mechanized coal mining face, when exploited, gradually enters the mining roadway of the
goaf. However, due to the influence of the dynamic pressure and some other factors generated during the service term, it is difficult to haul off and dismantle the anchor; therefore it is still in suspension and is being a part of reinforcement [1, 2].
As the roof collapses into the
goaf behind the roof supports, the fracturing and settlement of the rocks progresses through the overlying strata and results in sagging and bending of the near surface rocks and in some cases subsidence of the ground above [11].
But in Australia responsible operators are now exploiting methane from these closed/sealed underground mines using a technique called the "coal mine
goaf gas predictor" (CMGGP).