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81.
采用现代构造几何分析方法,研究了巢湖煤田的控煤构造,发现巢湖煤田主要受大型平卧式褶皱逆冲推覆构造控制。按构造变形特点从南到北可以划分为和县-含山平卧式褶皱推覆构造、巢湖银屏山平卧式褶皱推覆构造和无为平卧式褶皱推覆构造 3个构造带,卷入了震旦系灯影组-三叠系的整个扬子海相沉积盖层。这种大规模的褶皱逆冲推覆是扬子板块沿着郯庐断裂向华北板块A型俯冲的产物。 相似文献
82.
根据克希霍夫积分法的原理,介绍了叠前时间偏移的方法特点,实现过程,以及对地震资料的要求,依托国家重大产业技术专项“西部煤炭资源高精度三维地震勘探”工程,对“青海省鱼卡煤田四井田高精度三维地震勘探”资料进行叠前时间偏移,结果表明其能较好地解决成像质量差、能量聚焦不明显、绕射波收敛不理想等方面的难题。通过与叠后时间偏移对比,对于大倾角地层、断块小且多的破碎带、陡倾角不对称向斜等地质问题,其叠前时间偏移剖面成像质量都有明显的提高,反映的构造关系更加清晰,同相轴连续性增强。总结该方法在多个矿区的推广经验.认为合理的观测系统、较高的资料信噪比,准确的测量资料及较高的中表层速度调查精度是做好叠前时间偏移的前提。 相似文献
83.
Jian Chen Guijian Liu Mengmeng JiangChen-Lin Chou Hui LiBin Wu Liugen ZhengDongdong Jiang 《International Journal of Coal Geology》2011,88(1):41-54
To study the geochemical characteristics of 11 environmentally sensitive trace elements in the coals of the Permian Period from the Huainan coalfield, Anhui province, China, borehole samples of 336 coals, two partings, and four roof and floor mudstones were collected from mineable coal seams. Major elements and selected trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and hydride generation atomic absorption spectrometry (HAAS). The depositional environment, abundances, distribution, and modes of occurrence of trace elements were investigated. Results show that clay and carbonate minerals are the principal inorganic constituents in the coals. A lower deltaic plain, where fluvial channel systems developed successively, was the likely depositional environment of the Permian coals in the Huainan coalfield. All major elements have wider variation ranges than those of Chinese coals except for Mg and Fe. The contents of Cr, Co, Ni, and Se are higher than their averages for Chinese coals and world coals. Vertical variations of trace elements in different formations are not significant except for B and Ba. Certain roof and partings are distinctly higher in trace elements than underlying coal bench samples. The modes of occurrence of trace elements vary in different coal seams as a result of different coal-forming environments. Vanadium, Cr, and Th are associated with aluminosilicate minerals, Ba with carbonate minerals, and Cu, Zn, As, Se, and Pb mainly with sulfide minerals. 相似文献
84.
There were three landforms (i.e. desert, bedrock platform and loess gully) in deep-buried coalfield of northern Ordos Basin. Water inflow of working face in desert area was 1~2 orders of magnitude larger than that in other landform areas. In order to find out the key controlling factors of the directly water filled aquifers on the roof of the coal seam, we carried out research from the aspects of topography, landform and geological sedimentation. The results showed that desert landform provides abundant recharge water for underlying aquifers because of gentle topography, large precipitation infiltration coefficient, thick and water-rich quaternary system. While bedrock platform and loess gully landform were the water sources with weak recharge capacity of underlying aquifers. The sandstone-mudstone interbedding structure formed by continental deposits resulted in the absence of regional stable aquifers in Jurassic and Cretaceous strata on the roof of coal seams. Pumping tests of boreholes showed that all strata belong to weak to medium water-rich aquifers. The groundwater level of Cretaceous aquifer decreased by 20~130 m in three mines. There was a close hydraulic relationship between shallow and deep aquifers. The Mesozoic strata belonged to fluvial deposits. Qilizhen sandstone and Zhenwudong sandstone aquifers were mainly developed on the roof of the coal seam, which were characterized by thick medium-coarse sandstone sections. The geological and sedimentary conditions of direct water-filled aquifer were similar, but the amount of borehole water, cumulative pre-drainage water and water inflow from goaf in desert geomorphic area were much larger than those in bedrock platform and loess gully geomorphic area. The water-rich of the aquifer was mainly controlled by geomorphology, and the water sources of the deep aquifers were meteoric precipitation and Quaternary aquifer. In different mines with similar Quaternary conditions in Mu Us Desert, there were also great differences in the amount of borehole water, cumulative pre-drainage water and water inflow from goafs. The difference was related to the thickness and lithology of the aquifers. It reflected that the geological sedimentary conditions of the coal seam roof were also important factors to control the water-rich of the aquifers. Topography, landform and geological sedimentation were the key factors to control the water-rich of the aquifer directly and the water inflow from the working face. 相似文献
85.
邢台隆东井田煤变质情况复杂,直接影响煤的工业利用。利用X-射线衍射(XRD)法探讨了区内不同变质程度煤的基本结构单元特征及煤变质规律。结果显示:垂向上,随着煤层埋藏深度的增加,层片间距d002值逐渐减小,层片堆积高度Lc和层片直径La值逐渐增大;平面上,离岩浆侵入体越近,煤层的层间距d002值越小,反之d002值越大。在煤种分布上,因受岩浆热源的影响,井田内煤种以旧城为中心向外呈带状分布,旧城附近为无烟煤,向外逐渐过渡为贫煤、瘦煤、焦煤、肥煤和气煤。区内煤变质作用主要受区域变质作用影响,并叠加了岩浆热变质作用。 相似文献
86.
合山煤田是典型的岩溶充水矿床.矿井开采水害严重。煤层的直接顶、底板为碳酸盐岩类,岩溶极为发育,为矿井的直接充水含水层;煤层底部的茅口组为强岩溶含水层,与煤系地层的联系密切,为间接充水含水层;位于煤田两侧的红河水是矿井充水最主要的补给水源。断裂、节理和破碎带等通道是矿井充水的主要通道。通过分析井下突水点的发育特征,认为强岩溶导水带是矿井突水的关键部位,防治矿井水害的重点是切断岩溶导水带,对强导水带进行封堵,防止红水河的侧向补给,对四煤底板灰岩进行加固。总结出地面防治的主要方法为帷幕式、截堵式、堵水点式和地面铺盖式。对井下防治水,提出了有疑必探,先探后掘,设置防水闸门、防水墙,实行分层、分区开采,加强井下排水等防治措施。 相似文献
87.
笔者首次发现了内蒙古霍林河煤田霍林河组(K1h)茨康类拟刺葵属拟刺葵亚属的一个新种—内蒙古拟刺葵(Phoenicopsis(Phoenicopsis)neimengensis sp.nov.)。该新种以表皮构造下气孔式,上表皮细胞未见乳突,下表皮普通表皮细胞发育中央乳突,气孔器副卫细胞多发育乳突,孔缝不定向等特征区别于拟刺葵属已知种。新种的研究对于了解拟刺葵属(Phoenicopsis)的分类,以及恢复古地理、古气候有重要作用。 相似文献
88.
川南煤田古叙矿区煤层气勘探选层的探讨 总被引:1,自引:0,他引:1
川南煤田煤炭资源占四川省煤炭资源的60%以上,评价的煤层气资源最占80%以上。通过煤炭资源勘查、煤层气参数外资料分析,认为将龙潭组全段作为一个目的层段研究,将有助于全方位客观评价四川省煤层气的勘探开发前景。根据煤层间距小、储层参数差异小、含气量高等条件提出了以C12-C14、C15-C21、C23-24C、C25煤层群(组)作为目的煤层的观点,并提出必须加大施工排量、多打铺垫液、提高加砂浓度的压裂改造等建议,以期对南方小盆地多煤层的煤层气开发提供新的思路。 相似文献
89.
90.
李元仲 《中国地质灾害与防治学报》2014,25(3):62-66
陶枣煤田周边分布有丰富的裂隙岩溶水资源,且易于开采,为区内城市生活的主要供水水源。长期以来,受煤炭资源开采影响,岩溶地下水受到了不同程度的污染,供水水质难以保证。本文在对裂隙岩溶地下水水质进行污染评价的基础上,根据污染时空分布特征以及地质、构造条件,分析了区内岩溶地下水的污染机理,并提出了可行的防治措施。 相似文献