鹤岗煤田深部煤炭资源潜力分析研究

根据矿区已有地质资料,从构造、沉积古地理环境分析,认为鹤岗煤田深部与煤田现生产区属同一个沉积环境,其古构造条件、沉积体系及成煤环境相同,煤田深部预测区是生产区的延深。依据钻探、物探对深部构造及煤层的控制,证实煤田深部煤层发育较稳定,具有一定的煤炭资源潜力,值得进一步勘查和开发利用。     

美国印第安纳州宾夕法尼亚系含煤地层和煤层简介

美国中部伊利诺伊煤田(跨伊利诺伊、印第安纳、肯塔基等三个州)的含煤地层为上石炭统宾夕法尼亚系。美国印第安纳地质研究所2006年编制的印第安纳州基岩综合地层柱状图建立了宾夕法尼亚系含煤地层的岩相层序,现将此岩相层序介绍到国内,对我们了解美国晚古生代煤田地质及阅读国外文献资料颇有帮助。     

河北南部峰峰煤田山西组沉积特征与沉积环境演化

通过研究峰峰煤田山西组岩性和沉积构造特征,将山西组划分为四个沉积旋回,根据沉积环境的演化,分析了其对成煤作用的影响,认为区内山西组为典型的河控浅水三角洲沉积,该沉积体系中的聚煤作用较强,尤其是分流间洼地持续发展的部位形成了较厚煤层,由于分流河道的迁移作用,煤层分叉现象,而且成煤后遭河道冲刷导致变薄或缺失。     

利用地震属性预测煤层厚度及古河流冲刷带的方法

根据山西宁武煤田某煤矿2#煤层采掘及钻孔揭露情况,发现该井田中部和南部存在古河流冲刷带。通过对比基于优选的4个地震属性的四元一次、四元二次多项式回归模型与BP神经网络预测模型,决定将BP人工神经网络模型预测煤层厚度数据应用于整个测区古河流冲刷带的预判工作。首先利用GeoFrame系统和Landmark公司Poststack模块,提取2#煤层反射波的各类沿层切片,分析并圈定出2#煤层古河流冲刷带的大致范围,在此基础上,利用垂直时间剖面中2#煤层反射波的各种波形特征,进一步判别2#煤层古河流冲刷带解释的可靠性,然后结合BP神经网络预测模型获得的2#煤层厚度变化趋势图,最终解释出2#煤层古河流冲刷带范围:勘探区内2#煤层厚度变化范围0～5.3m,根据其煤层厚度变化趋势,将全区划分出一大二小3个古河流冲刷带。     

山东阳谷茌平煤田阿城井田山西组煤岩层对比研究

通过对山西组沉积特征及聚煤变化规律的研究,采用煤岩层组合特征、标志层、层间距、测井曲线形态和地震物性特征等方法,对井田内山西组的煤、岩层进行综合对比。确定了山西组主采煤层的赋存层位、形态及区内的构造方案,对周边地区找煤工作具有指导作用。     

陕西黄陇煤田侏罗系煤层气开发关键技术

黄陵煤田侏罗纪煤层裂隙发育,渗透率高,煤层气开发的地质条件优越,即将成为我国煤层气开发一个重要的潜在接替领域,根据焦坪矿区和彬长矿区煤层气开发取得的成果,详细探讨了煤层气开发方式、井位部署、钻完井工艺、压裂工艺和排采工艺等关键技术,指出欠平衡钻进、基于储层保护的洞穴完井和分层控压联合排采将是该区煤层气开发技术发展的方向。     

矿井涌水量预测的几种常用方法对比——以宁夏宁东煤田鸳鸯湖矿区麦垛山煤矿11采区水文地质补勘为例

我国许多煤矿区,由于地下水频繁突入,造成淹井或因突水威胁使大量煤炭资源难以开发。因此,准确预测矿井涌水量,为矿井防治水提供依据,对煤矿床安全开采和长远发展至关重要。以宁东煤炭基地麦垛山煤矿为例,采用解析法、水文地质比拟法和三维渗流数值法等六种预测方法,对该煤矿11采区110203、110208工作面2#煤顶板直罗组底部砂岩含水层进行了涌水量预测。通过各种方法的分析比较,最后推荐采用最小二乘比拟法预算结果做最终矿井涌水量。     

福建煤田深孔钻探施工技术探讨

福建煤田地质构造复杂,断层发育,岩层极其破碎且较松软,泥岩受挤压破碎为薄片状或烂泥状,给钻探施工造成许多困难,比如泥页岩水化膨胀,孔壁失稳导致孔内坍塌严重等。采用绳索取心技术,优选金刚石钻头,科学确定泥浆配比和钻进参数,成功解决了这些孔内技术难题,提高了钻探效率,降低了生产成本,取得的施工经验可供该矿区或该类地层的钻探施工借鉴。     

Mine-drainage water from coal mines of Kerman region,Iran

Two types of mine-drainage water were recognized in Kerman coalfield, namely neutral to alkaline and acid (AMD). Both types contain a high level of trace-metal concentrations with a higher level in AMD. Trace metals from the coal-mine waters of Kerman coalfield are mainly present as adsorption on Fe and Mn oxide and hydroxide particles, and to a lesser extent as sulfate, simple metal ions and as metal sorption on clay particles and hydrous aluminum oxides.     

Electrical Resistivity Imaging technique to delineate coal seam barrier thickness and demarcate water filled voids

Exploration and exploitation of coal seams is one of the major resources for the energy sector in any country but at the same time water filled voids/water logged areas in the old workings of these seams are very critical problems for the coal mining industry. In such situations, disasters like inundation, landslides, collapsing of the old seams may occur. In this regard, it is necessary to find out the water saturated/water filled voids and zones in the mining areas. Since no established technique is available to find such zones, an experimental study using Electrical Resistivity Imaging (ERI) has been carried out in one of the coal mining areas near Dhanbad, to find out the feasibility of finding the barrier thickness and the water logged area in underground coal mines. The area under study forms part of Jharia coalfield in Dhanbad district, Jharkhand state. The coal bearing rocks of Barakar Formation of Lower Permian age (Gondwana period) occur in the area under a thin cover (10 m to15 m) of soil and or alluvium. Coal bearing Barakar Formations consist mainly of sandstone of varying grain size, intercalation of shale and sandstone, grey and carbonaceous-shale and coal seams. Since the water saturation reduces the resistivity of a formation to a large extent, water filled voids and old coal workings are expected to have significant resistivity contrast with the surrounding host rock. Hence, ERI technique was applied in such an environment as this technique uses high-density data acquisition both laterally and vertically by using multiple number of electrodes. Along with ERI, mise-à-la-masse (also called charged body) technique was also employed at one of the promising sites to find out the connectivity of water logged areas and also detection of these old workings from the surface measurements was analyzed. The interpreted 2D resistivity sections have clearly indicated the water bearing zone(s) along the profile which was well confirmed with the existing water level in the nearby borewells. On the other hand, this technique did not identify the size of the coal pillar and gallery (air filled voids), which might be due to the small size of the voids (i.e. about 2 m × 2 m) below a depth of 15m and more but have indicated altogether as a high resistive zone ranging from 600–1000 Ohm-m.