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21.
在全面分析大雁矿业集团公司雁南煤矿北二采区的水文地质条件及煤层开采矿井充水因素的基础上,计算了开采27^1号煤层时导水裂隙带发育高度.得出了北二采区各煤层工作面开采即不会受到上部砂砾含水层的影响,雁南煤矿铁路涵洞以西的胜利河冲击沟也不会受到北二采区的采动塌陷影响的结论。 相似文献
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美国西南干旱半干旱地区人口增长非常快。水不仅要满足基本的需求(饮用水、污水系统等),而且还要维持乡村潮湿地区生活方式的改变(郊区的草地、高尔夫球场、庭院的游泳池等)。这些水的使用,既能满足供水系统所在区域地表水供水的需求,又可以满足最基本的地下水开采。然而,地下水的开采对沉积含水层有不利的影响,这些含水层是特有的沙漠区地下水流域的承载。这些影响包括含水层不同程度的压实、旧断层的重新复活、地表的裂缝,还能对人为的基础设施有相当大的影响。 相似文献
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Wei ZHANG Yilian LI Tianfu XU Wei QIANG Shangping XIAO 《中国地球化学学报》2006,25(B08):58-58
Since industrial revolution, the "greenhouse effect" is one of the most important global environmental issues. Of all the greenhouse gases, CO2 is responsible for about 64% of the enhanced "greenhouse effect", making it the target for mitigation, so reducing anthropogenic discharge of carbon dioxide attracts more and more attention. Geological sequestration of CO2 in deep saline aquifers is one of the most promising options. But because unknown fractures and faults may exist in the caprock layers which can prevent the leakage of CO2, CO2 will leak upward into upper potable aquifers, and lead to adverse impacts on the shallow potable aquifers. In order to assess the potential effect of CO2 leakage from underground storage reservoirs on fractures and water quality of potable aquifers, this study used the non-isothermal reactive geochemical transport code TOUGHREACT developed by Xu et al to establish a simplified 2-D model of CO2 underground sequestration system, which includes deep saline aquifers, caprock layers, and shallow potable aquifers, and study and analyze the changes of mineral and aqueous components. The simulation results indicated that the minerals of deep saline aquifers and fractures should be mainly composed of aluminosilicate and silicate minerals, which not only enhance the mass of CO2 sequestrated by mineral trapping, but also decrease the porosity and permeability of caprock layers and fractures to prevent and reduce CO2 leakage. The results from deep saline aquifers showed that the mass of carbon dioxide trapped by minerals and solution phases is limited, the rest remained as a supercritical phase, and so once the caprock aquifers have some unknown fractures, the free carbon dioxide phase may leak from CO2 geologic sequestration reservoirs by buoyancy. 相似文献
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Teddy W. Sudinda Teddy 《中国地球化学学报》2006,25(B08):156-157
Flood and desiccation are perceived as two most critical and influential disasters which contradict between causes and consequences. Flood occurs when the water surface could no longer flow the whole water flow, thus, the water flooded. Contradicted to that, desiccation occurs when the water flow contains a low volume of water deposit, thus, the water requirement exceeds the available potential. That condition was caused by land utilization as the consequences due to the increased land requirement for housing or industrial needs. An attempt to overcome the flood, nowadays, is implemented mostly in a structural way, through building canals, implementing rivers normalization, building gateways or building flood control pump which are more directed toward the flood direction in order to increase the surface flow in an immediate maner to the sea. However, the effort to overcome the flood its self, could be more effective if followed by an effort to increase the soil ability to absorb natural recharge or artificial recharge or by refilling the water into the earth surface. Absorption reservoir used as one of technology alternatives (artificial recharge) could also be used to support the attempt to overcome flood and desiccation. Absorption reservoir is a dam which was designed according to the basic principles, such as the bottom surface of the reservoir that has a high permeability surface; the surface of the reservoir water is higher (higher aquifer) along with a high permeability, considering the availability of water source that has been absorbed and its quality; considering the aquifer category on the water absorption dam; 相似文献
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在PAKSEY大桥的施工过程中,对节段梁的预制、节段梁的悬臂拼装以及桥面体系的施工进行了精密的测量控制,从而使桥面线形与设计线形的误差最小。 相似文献
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辽河盆地冷家油田沙河街组三段储层岩相古地理 总被引:2,自引:0,他引:2
辽河盆地在沙河街组三段早期水体较深,主要形成扇三角洲及盆底扇;沙三晚期水体较浅,发育湖泊砂体.依据沉积相分布规律,沙三早、中、晚3个时期可进一步分别划分出湖泊扩张和收缩阶段.盆地西部凹陷的冷家油田为东陡西缓的箕状洼陷.研究区内沙三段的古地理格局是决定相分布的关键因素,河流和湖泊能量相对强弱决定扇体沉积的规模.受相对湖平面变化的影响,纵向扇三角洲主要形成于湖泊扩张时期,并且有相带窄、过渡快、以粗碎屑沉积为主的特点.扇体沉积中主要发育前缘分流河道充填沉积,但位于河口前缘或侧缘的滩坝及前三角洲中的盆底扇局部也较发育. 相似文献
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鲍店煤矿突水条件分析 总被引:3,自引:0,他引:3
对影响鲍店3煤安金井采的3煤顶、底部砂岩和红层的水文地质条件进行了分析,对其突水特征作了简明讨论,应用突水判别模式对本矿十采区作了安全开采评价,划分了可能突水的工作面,对今后的安全开采有一定的指导意义. 相似文献