## 4 Structural Control Mechanisms on Coal and Gas Occurrence in Mines
### Structure-Controlled Gas Prevention and Mitigation Measures  
Based on the structural development characteristics of the Kaiping syncline, coal seam distribution features, gas occurrence patterns, and controlling factors, gas outburst prevention in structurally developed areas must comply with the Regulations on the Prevention and Control of Coal and Gas Outbursts [32]. The principle of \"regional comprehensive outburst prevention measures first, supplemented by local comprehensive outburst prevention measures\", must always be adhered to. In line with the requirements of \"one strategy for one mine, one strategy for one face\", the goals of \"drainage before construction, excavation, and mining, as well as achieving pre-drainage standards\", can be achieved. Outburst-prone coal seams must implement the two \"four-in-one\" comprehensive outburst prevention measures to ensure that multiple strategies are applied, safety is ensured, gas drainage is optimized, and the desired results are achieved. Failure to comply will strictly prohibit mining and excavation activities. The specific prevention and control measures are as follows:  
1. Minimize the number of times that roadways expose (or intersect) outburst-prone coal seams. The locations for exposing (or intersecting) such coal seams should reasonably avoid geological structural zones, especially areas with compressive-shear faults and well-developed fractures. 2. For areas predicted to be free of outburst risk, regional prediction can be performed block by block using measured coal seam gas parameters, coal seam occurrence, and geological structures within the section. 3. Based on coal seam occurrence characteristics, geological structure conditions, outburst distribution patterns in the mined areas, and detection and prediction results of coal seam geological structures in the forecasted areas, the gas geological analysis method is applied to delineate outburst hazard zones. If the distribution of outburst points or locations with significant warning signs is directly associated with a structural belt, the extended position of this structure and the coal seam within a specific  
Figure 11: The relationship diagram of structure, buried depth, and gas content of No. 9 coal seam: (**a**) Zhaogezhuang mining area; (**b**) Lixxi mining area. range on both sides are classified as outburst hazard zones. Otherwise, within the same geological unit, the coal seam extending 20 m (vertical depth) above and below the outburst point or location with significant warning signs is also classified as an outburst hazard zone. (4) Inspection and testing points in each study area should be located in regions with lower borehole density, wider borehole spacing, and shorter pre-drainage times. These points should be positioned as far as possible from pre-drainage gas boreholes or equidistant from surrounding boreholes, where feasible, to avoid the discharge range of excavation roadways and the pre-drainage advance distance of working faces. In geologically complex areas, the number of inspection and testing points should be appropriately increased, with special attention to closed faults (e.g., compressive or compressive-shear faults), which act as barriers, obstruct gas emissions, and seal against gas dissipation. (5) For every 10-50 m of working face advancement--or every 30 m in geologically complex areas or pre-drainage gas regions using non-directional drilling rigs--at least two regional verifications must be performed. Comprehensive records of engineering design, construction, and performance inspections must be meticulously preserved. Continuous regional verifications should be conducted in structurally damaged zones to analyze fault zone characteristics, including fault fillings, fracture development, and the properties of rock layers contacting the coal seam on the opposite fault block.