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With depleted coal resources or deteriorating mining geological conditions, some coal mines have been abandoned in the Fengfeng mining district, China. Water that accumulates in an abandoned underground mine (goaf water) may be a hazard to neighboring mines and impact the groundwater environment. Groundwater samples at three abandoned mines (Yi, Er and Quantou mines) in the Fengfeng mining district and the underlying Ordovician limestone aquifer were collected to characterize their chemical and isotopic compositions and identify the sources of the mine water. The water was HCO3·SO4-Ca·Mg type in Er mine and the auxiliary shaft of Yi mine, and HCO3·SO4-Na type in the main shaft of Quantou mine. The isotopic compositions (δD and δ18O) of water in the three abandoned mines were close to that of Ordovician limestone groundwater. Faults in the abandoned mines were developmental, possibly facilitating inflows of groundwater from the underlying Ordovician limestone aquifers into the coal mines. Although the Sr2+ concentrations differed considerably, the ratios of Sr2+/Ca2+ and 87Sr/86Sr and the 34S content of SO42− were similar for all three mine waters and Ordovician limestone groundwater, indicating that a close hydraulic connection may exist. Geochemical and isotopic indicators suggest that (1) the mine waters may originate mainly from the Ordovician limestone groundwater inflows, and (2) the upward hydraulic gradient in the limestone aquifer may prevent its contamination by the overlying abandoned mine water. The results of this study could be useful for water resources management in this area and other similar mining areas. [ABSTRACT FROM AUTHOR]

The aim of this article is to provide a better understanding of long-term uneven resilience by critically exploring the notions of adaptation and adaptability. Moving beyond the conventional trade-off assumption, the article proposes three main types of adaptation–adaptability relationships: Competing, Separated and Reciprocal, as an analytical approach to explain uneven regional resilience. Two empirical case studies of municipal-level mining regions with a common crisis of coal exhaustion in China, namely Zaozhuang and Fuxin, show how variations of adaptation–adaptability relationships result in uneven resilience. [ABSTRACT FROM AUTHOR]

Igneous intrusions are distributed extensively in the Huaibei coalfield, China. In the Haizi coal mine, coal and gas outbursts have occurred 11 times under an extremely thick sill (average thickness 120 m). This paper presents the results of a study on the influences of the igneous rock on coal pore structure, methane desorption and diffusion properties, and coal seam gas occurrence. The results show that the thermal evolution effect of the igneous sill prominently increases the specific surface area and pore volume of the affected coal. Samples HZ1 and HZ2 (No. 7 and No. 9 seams, respectively) closer to the sill possess improved pore connectivity, while samples HZ3 and HZ4 (away from the sill) and sample HZ5 (without sill covering) of the No. 10 coal seam have poor pore connectivity. Moreover, the effective diffusivity and desorption indexes of the coal increase progressively closer to the sill. The thermal effect of the igneous sill promotes the development of coal pores, thus leading to better pore connectivity, more desorbed gas, and much higher gas desorption and diffusion rates. Consequently, the thermal evolution effect of the igneous sill can change the occurrence and characteristics of the entrapment effect in the underlying coal seams, thus resulting in a high probability of gas hazards or even coal and gas outbursts in the coal seam close to the igneous sill. Engineering practices show that the affected coal seams have high gas content, gas pressure, and gas emission amounts as well as a high propensity for coal and gas outburst. [ABSTRACT FROM AUTHOR]

Mining activities seriously interfere with the regional land use, which lead to a strong influence in ecosystem. After collecting many studies related to ecosystem service values (ESVs) in resource-based cities in China, this paper extracts a series of variables with Meta-analysis to establish benefit transfer models for assessing ESVs of cultivated land, forest land, grassland and waters especially in mining cities, then examines the feasibility of these models in Wu’an City to evaluate the ESVs of Wu’an in 1987, 2001 and 2014. The results show that: 1) the benefit transfer method can effectively assess the ESVs in mining cities; 2) there is a declining trend after the increase in the total ESVs of Wu’an, and a significant decrease occurred after 2001; 3) from the aspect of land area, the degree that the mining activities interfere with the land use type is cultivated land>grassland>waters>forest land from 1987 to 2014; from the aspect of the ESVs, the degree that the mining activities interfere with the land use type is cultivated land>waters>grassland>forest land; and 4) when the total area of ecological land reduces, a reasonable optimization of ecological land structure can improve the total ESVs rather. [ABSTRACT FROM AUTHOR]

The article focuses on the mechanism of tear of shaft linings in the coal mine areas, which are buried by thick over-soils in East China. Mining does not directly induce the ruptures in the shaft linings, because there are sufficient wide coal pillars, which protect the shaft and surface industrial areas. Non-mining rupture of shafts in coal mine areas is a new kind of geological disaster. The major engineering geology conditions for shaft lining rupture are: (a) deep soil (generally more than 200m); (b) an aquifer with high water pressure at depth; (c) obvious water-head lowering in the deep soil aquifer.

The article discusses situation for prospecting and related suggestions for the Xiushan Manganese Ore in the southeast of Chongqing City in China, and mentions that manganese ore is one of the superior minerals of the city. Suggestions include strengthening the metallogenic theory research, need of need a large-scale mining geological survey, and intensifying the periphery of old mines and deep prospecting work.