榆横南区地下采煤对地表水库坝体影响的安全性研究

以魏墙煤矿1313工作面为例,通过对矿井地质、水文地质条件进行分析,确定工作面开采的主要充水水源和充水通道,结合先期地表移动变形实测成果、应用概率积分法对1313工作面回采后造成的地表塌陷进行预测,从而判断地表水库坝体的损伤程度。结果表明:矿井开采的3号煤层顶板侏罗系延安组第四段和直罗组砂岩含水层为1313工作面开采时的主要充水水源,覆岩导水断裂带为主要充水通道,大气降水、地表水库水体均不会被沟通导入井下;而回采后地表塌陷变形将造成水库坝体的Ⅳ级损伤,极可能造成水库水体外溢、灌入下游农田的危险。     

基于模糊综合评判法的关闭矿井地下水水质分类

矿井在关闭以后,随着时间延续,地下水中的污染物会向远处和深处扩散。及时对关闭矿井地下水进行水质定量评价,并根据评价分级结果采取相应处理措施尤为重要。为了对龙永煤田关闭矿井地下水进行水质定量评价及分级,参照地下水5级水质分类标准,选取地下水总硬度值、溶解性总固体值、硫酸盐含量、氯离子含量等4个指标,利用模糊综合评判法,对龙永煤田15个关闭矿井的152组地下水水样逐一进行定量评价分类。结果显示,15个已关闭矿井地下水总体水质偏差,大多属于第Ⅳ级水、第Ⅴ级水,第四系孔隙水和童子岩组裂隙水基本不能作为饮用水源来使用。下部灰岩层水质相对较好,但不宜开采,应做好保护。研究结果为下一步矿山环境修复治理提供了参考。     

二维地震技术在河南省偃龙煤田勘查中的应用研究

河南省偃龙煤田位于基岩低山丘陵—黄土山坡向平原过渡地带,地形条件极为复杂,区内居民点、工业园区密集,公路较少,地震勘探施工难度大。此外,浅层地震地质条件差,地震数据采集难度大。偃龙煤田西村煤矿勘查经历了普查、普查续作和详查三阶段地震勘探工作,为了取得较好的地震勘探效果,各阶段地震勘探都经历了的数据采集反复试验,在此基础上才取得了勘探成果,因而也积累了该区地震勘探数据采集经验。重点总结介绍该区不同地貌地表条件下,二维地震勘探各种激发方式、采集参数和最终勘探成果,以供读者参考。     

Coalbed methane-produced​ water characteristics and insights from the Jharia coalfield in India

Coalbed methane (CBM) has emerged as one of India’s important unconventional natural gas sources in the past decade. A number of environmental questions flank the commercial development of CBM and its holistic success, one of which is coproduced water management. Present work aims at assessing the geochemistry of co-produced water samples collected from CBM wells in Jharia coalfield, India. It is found that pH is within accepted limits and the bacterial contamination is minimal. The major ions present in the water samples are sodium and bicarbonate. It is observed that the produced water is generally influenced by a mix of evaporite dissolution and silicate weathering and the samples are oversaturated with respect to calcite and dolomite. Subsequently, an assessment of the energy requirements of membrane-based technologies (such as reverse osmosis and nanofiltration) has been performed. The estimated energy consumption is 0.45–1.40 kWh per cubic meter of water, for differing levels of sodium desired in treated water. Membrane-based methods seem to be effective for treatment of CBM co-produced water, and the selection of membranes can be based on the geochemistry and also the level of treatment desired.     

陇东煤田侏罗系煤层气成藏主控因素与模式

鄂尔多斯盆地西南缘陇东煤田低阶煤层气资源丰富,勘查开发处于起步阶段,成藏主控因素及模式认识尚不足。为弄清气体的富集规律,优选勘探靶区,运用钻探(现场解吸、试井、岩芯)、测井、水文、地球化学测试等资料,从构造演化、埋深条件、沉积环境和水文地质条件等方面讨论了气藏的煤储层特征、主控因素和富气成藏机制,划分出4种煤层气富集成藏模式及对应的气藏类型;评价优选出3个有利勘探区。结果表明:陇东地区煤层厚度大,煤系地层非均质性强,煤岩煤化程度低,含气量横向变化大;煤岩生烃能力强,储集性能好,富气成藏的主控因素为盖层的发育程度和后期次生生物气的调整;埋深控藏呈现出"最佳深度"的特征。该结果为后期煤层气勘探的井位部署提供了参考和指导。     

Distribution and significance of＂barkinite＂ in Mowo coal mine of Han-Xing coalfield, North China

In order to study the distribution and significance of "barkinite" in the Han-Xing (Handan-Xingtai) coalfield, northern China, 140 samples were collected from 10 coal mines and then analyzed by maceral separation, Rock-Eval and microscopic method. The results indicate that "barkinite" can be observed in samples from only three mines with a value lower than 2%. The "barkinite" from the Mowo mine was studied in detail because of its relative high content of"barkinite". In addition, the HI value of"barkinite" is higher than that of the coal seam as a whole, showing that "barkinite" has considerable potential for hydrocarbon generation.     

基于抽水试验和放水试验的断层导水性分析北大核心

为了避免断层水害和煤层顶底板砂岩水害的发生,需要准确掌握断层的导水性;通过延安组底部宝塔山砂岩含水层的大流量大降深放水试验,查明了DF_(20)断层在垂向上具有良好的导水性,是各含水层水力联系的重要通道,同时明确了DF_(20)和F_(2)断层在水平方向上具有导水性,三叠系含水层通过DF_(20)和F_(2)断层与宝塔山砂岩含水层等具有水力联系;探查了DF_(20)断层与FD;断层交汇处导水性最强,是各含水层水量交换的主要位置;确定了DF_(20)断层导水性在水平方向上具有不均一性,DF_(20)断层位于井田中部的区域导水性较弱,而井田南部区域导水性较强。结果表明:通过抽水试验和放水试验不仅可以获取断层的水文地质参数,同时可以查明断层的导水性及其空间特征。