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181.
运用地质力学的观点分析阳泉矿区地质构造,探讨构造体系,构造演化及其形成机制。作者认为,阳泉矿区地质的构造格局是东西向构造带和新化夏的构造带互相复合造成的,矿区内煤系底部的岩浆岩侵入体,在新华夏系南北向扭力作用时起了砥柱作用。 相似文献
182.
Mining activities induce profound changes to societies and the environment they inhabit. With global extraction of metal ores doubling over the past two decades, pressures related to mining have dramatically increased. In this paper, we explore where growing global metal extraction has particularly taken effect. Using fine-grain data, we investigate the spatial and temporal distribution of mining of nine metal ores (bauxite, copper, gold, iron, lead, manganese, nickel, silver and zinc) across approximately 3,000 sites of extraction worldwide between 2000 and 2019. To approach the related environmental implications, we intersect mining sites with terrestrial biomes, protected areas, and watersheds categorised by water availability. We find that 79% of global metal ore extraction in 2019 originated from five of the six most species-rich biomes, with mining volumes doubling since 2000 in tropical moist forest ecosystems. We also find that half of global metal ore extraction took place at 20 km or less from protected territories. Further, 90% of all considered extraction sites correspond to below-average relative water availability, with particularly copper and gold mining occurring in areas with significant water scarcity. Our study has far-reaching implications for future global and local policy and resource management responses to mitigate the negative effects of the expected expansion of metal mining. 相似文献
183.
Mining activities have left huge uncovered slopes, large areas of gangue ground and extensive railings dams. In this paper, we studied some impacts of mining activities upon environment in Panzhihua region, southwestern China. The environmental impacts include ecological destruction, geological disasters, environmental pollution, land damage, solid waste and occupational health effect in study area. The author suggested that local government should take some measure to reduce environmental impact in Panzhihua City. First, the countermeasure of reducing environmental impact is to set up ecological rehabilitation and environmental management system, which ensure the sustainable development of resources, environment, economy and society in this region. Second, the area needs to be monitored regularly for trace metal and other pollutants to forewarn urban eco-environmental safety. 相似文献
184.
Underground coal mining can affect wells and springs used as water supplies. In Virginia, concerns over such impacts are
felt by both surface owners and coal-mining firms. Virginia's geologic history has caused faults and fractures to be common
in its coalfield region, relative to other Appalachian coal-mining areas. The results of 73 investigations of alleged domestic
water supply impacts by underground mining were analyzed; the investigations were conducted by the Virginia Division of Mined
Land Reclamation (VDMLR). This analysis was conducted with reference to guidelines that define a primary zone of underground
mining influence where dewatering of aquifers is to be expected. The VDMLR data set included 27 investigations of alleged
water supply impacts by partial-extraction room-and-pillar mines, 41 investigations of high-extraction room-and-pillar mines,
and 4 investigations of longwall mines. VDMLR investigators found that 14 of 16 water supplies within the primary zone of
influence were likely to have been affected by pillar-retreat mining, but no water supplies within the primary zone of influence
for longwall and room-and-pillar mines were represented in the data base. VDMLR investigators found 42 of 56 water supplies
outside of the primary zones were likely to have been affected by mining; these cases represented room-and-pillar, pillar-retreat,
and longwall mining. Geologic circumstances not directly related to subsidence were found to be responsible for 31 of these
42 impacts. These geologic circumstances included subsurface fractures and other geologic features acting as aquifers that
were drained by underground mining operations. VDMLR investigators also found some of the investigated water losses to have
been caused by factors other than mining. These results demonstrate the inherent difficulties of any attempt to rigidly define
a "zone of underground mining impact" based solely on mine subsidence effects, especially in regions where geologic faults
and fractures are common such as the southwest Virginia coalfield.
Received: 4 August 1995 · Accepted: 23 October 1995 相似文献
185.
四川省北川县擂鼓盆地地壳稳定性与城镇选址 总被引:4,自引:1,他引:3
5·12汶川地震造成四川多座县城遭受毁灭性破坏,北川县城几乎被地震夷为废墟,因此灾后重建选址成为震后迫切需要开展的工作。野外地质调查和综合分析认为,尽管北川县擂鼓镇所在的擂鼓盆地处于强烈活动构造带,但盆地处于活动断裂的下盘,盆地基底整体性较好,内部断裂不甚发育,是活动构造带中的相对稳定地块,即“安全岛”。这个地区在北川县地震灾后重建中具有重要的利用价值。本文基于野外活动断裂和地震地质灾害调查,运用李四光先生的“安全岛”理论,初步论证了擂鼓盆地的地壳稳定性,并从环境工程地质角度分析了擂鼓盆地的工程地质和水文地质条件,对北川县地震灾后重建规划和灾民安置场地选址具有重要意义。 相似文献
186.
InSAR技术在矿区沉降监测中的应用研究 总被引:1,自引:1,他引:0
介绍了应用InSAR技术监测矿区地表沉降以及地下开采活动的原理;利用重轨差分InSAR技术获得了峰峰矿区地表ENVISAT和JERS 1的雷达形变干涉相位图;分析了在矿区地表沉降过程中ENVISATC波段和JERS 1 L波段形变干涉相位图的相干特性、相位特性以及干涉测量技术在矿区地表沉降监测中应用的可行性和局限性。实验结果表明,利用C波段和L波段雷达数据可以实施对矿区地表沉降的监测,但是C波段雷达受到空间干涉基线的限制更加严格,如果要实现对矿区地表沉降的监测,需要充分利用每个卫星回访时期的雷达数据,建立长时序的星载雷达形变干涉相位图序列,才能较好地实现矿区地表沉降监测。 相似文献
187.
Sediment storage and severity of contamination in a shallow reservoir affected by historical lead and zinc mining 总被引:1,自引:0,他引:1
Kyle E. Juracek 《Environmental Geology》2008,54(7):1447-1463
A combination of sediment-thickness measurement and bottom-sediment coring was used to investigate sediment storage and severity
of contamination in Empire Lake (Kansas), a shallow reservoir affected by historical Pb and Zn mining. Cd, Pb, and Zn concentrations
in the contaminated bottom sediment typically exceeded baseline concentrations by at least an order of magnitude. Moreover,
the concentrations of Cd, Pb, and Zn typically far exceeded probable-effects guidelines, which represent the concentrations
above which toxic biological effects usually or frequently occur. Despite a pre-1954 decrease in sediment concentrations likely
related to the end of major mining activity upstream by about 1920, concentrations have remained relatively stable and persistently
greater than the probable-effects guidelines for at least the last 50 years. Cesium-137 evidence from sediment cores indicated
that most of the bottom sediment in the reservoir was deposited prior to 1954. Thus, the ability of the reservoir to store
the contaminated sediment has declined over time. Because of the limited storage capacity, Empire Lake likely is a net source
of contaminated sediment during high-inflow periods. The contaminated sediment that passes through, or originates from, Empire
Lake will be deposited in downstream environments likely as far as Grand Lake O’ the Cherokees (Oklahoma). 相似文献
188.
在中厚煤层的开采中,通过采用无煤柱开采、分层开采与放顶煤相结合的方法,杜绝了因煤炭丢失而形成的碎煤体产生发热源;采取对变形失效密闭重新构筑,对开采方式以及对通风系统进行优化等措施,以尽量减少采空区的漏风;采用阻化剂和预防性注浆,来阻止煤炭自燃的发展;利用监测监控系统和人工检测网络,能够及时发现火患苗头,为适时采取措施提供了保障。 相似文献
189.
190.
《Geoforum》2016
Water conflicts are a significant issue in northern Chile, especially when linked to neoliberal economic activities – mainly mining – on the lands of indigenous peoples. In fact, political ecology tends to accentuate the ways in which their communities unite around a water-based territoriality and/or cultural politics when faced with ‘threatening’ outsiders. However, internal differentiation has become especially relevant to enable a more nuanced appreciation of local struggles and claims. Taking a political ecology of water perspective, this article analyses in what ways Intergenerational Dynamics (hereafter IGDs) shape the way indigenous communities articulate their collective vision of development when dealing with mining companies. In addition, it examines to what extent IGDs shape the key elements that constitute different positions regarding territory, and also assesses how such dynamics reflect age-related traditional interests and cultural senses of identity and territoriality. 相似文献