石嘴山矿区煤层中夹矸的矿物岩石学特征

石咀山矿区石炭二叠纪煤层中广泛分布着高岭岩夹矸,其层位稳定,矿物岩石学特征独特,是煤层对比的理想标志层。文章阐述了各夹矸的层位和覃度变化、岩石类型和特征、化学成分和矿物学特点,分析了夹矸的成因。     

韩城矿区煤层结构特征及其对微粒生成的影响

煤层气开发利用具有“资源、安全、环保”多重经济效益和社会效益。韩城矿区是我国煤层气勘探开发试验先导区之一,区内煤层气井中煤粉等固相微粒产出现象较为突出。为了查明韩城矿区煤层结构特征及其对微粒生成的影响作用,分析了煤层气开发主力煤层的煤层结构复杂程度,讨论了3、5和11号煤层中夹矸发育规律,表征了物理模拟实验条件下煤中夹矸与微粒生成的关系。结果表明:按主力煤层由早至晚发育顺序,其煤层结构由复杂趋于简单、夹矸发育层数减小、夹矸总厚降低。3号煤层中夹矸主要发育在桑树坪、下峪口及王峰井田。5号煤层中夹矸发育在矿区南部,夹矸总厚高值区集中在象山、薛峰和龙亭一带。11号煤层中夹矸分布遍及全区,具东部边缘发育程度高、西部发育程度低的特征。在物理破坏、水岩反应和层间压差作用下,煤中夹矸会成为微粒生成层位。泥质夹矸对微粒的生成数量、运移距离及相应的储层渗透性伤害影响尤甚。加强煤层结构特征分析有助于查明煤中夹矸岩性变化及分布特征,进而为有效防治微粒生成提供保障。     

太原西山矿区杜儿坪井田夹矸地球化学特征及其地质意义

为探明太原西山矿区杜儿坪井田夹矸的地球化学特征及其地质成因,用X射线衍射分析(XRD)、电感耦合等离子体质谱(ICP-MS)、电感耦合等离子体发射光谱(ICP-OES)、氢化物-原子荧光光谱(HG-AFS)、发射光谱法(ES)等方法对杜儿坪井田2号、3号和8号煤层夹矸进行了矿物学和地球化学特征研究。结果发现2号、3号和8号煤层夹矸中矿物以高岭石、石英为主;与华北上地壳相比,杜儿坪夹矸中富集有害微量元素Cd、Se、Mo、Pb、Be、Cu、Th和U,山西组夹矸中有害元素含量大于太原组(除Mo、Pb和U);所有夹矸样品中Li、Ga的含量超过了工业品位,其工业利用价值值得关注;山西组夹矸稀土元素总含量高于太原组夹矸,所有夹矸稀土元素分配模式反映其与陆源碎屑关系密切;通过分析得到该区夹矸形成期间的陆源碎屑主要来自北部的花岗岩;太原组夹矸形成过程受海水影响;稀土元素与Al和Si等造岩矿物的聚类分析表明,夹矸中稀土元素主要赋存于高岭石等黏土矿物中。     

霍林河矿区17号煤层夹矸的电子显微学研究

本文用透射电了显微镜和扫描电子显微镜对内蒙霍林河矿区17号煤层夹矸做了系统的观察,在 0.l～10μm的数量级上分析研究了夹矸的矿物形成、结构及演化,总结了一组能说明夹矸成因、指导夹矸用途的电子显微学特征。以此为依据,推测该夹矸的物质来源主要为火山灰,可定名为“tonstcin”。     

含夹矸煤层槽波频散特性及其影响因素分析

槽波地震勘探是常用的井下物探技术,为达到预测煤层夹矸结构的目的,依据弹性波理论,推导了含夹矸煤层的勒夫型槽波频散方程,在此基础上,分析了夹矸的结构和物性变化对槽波频散特性的影响。研究表明槽波频散特性受夹矸厚度、位置以及速度变化的影响较大:夹矸厚度越大,夹矸距离煤层中心位置越近,夹矸速度越大,勒夫型槽波的速度就越大,埃里相特征也就越不明显。     

薄互煤层中透射槽波探测断层的正演模拟

为了研究西南地区矿井薄互煤层中透射槽波探测断层的可行性,选择具有代表性的攀枝花煤业集团某矿为研究对象,根据实际地质资料建立不含夹矸、含3层夹矸、含3层夹矸和断层的3个薄互煤层的地质模型,通过三维弹性波正演模拟分析槽波的波场特征和频散特征,总结振幅衰减系数成像在薄互煤层中槽波探测断层发育位置及延展方向的有效性;并结合实际应用,探讨了透射槽波在薄互煤层中的传播速度及频散特征,以及断层、夹矸对槽波传播的影响。结果表明:薄互煤层中透射槽波探测,断层在影响薄互煤层槽波传播中占主导作用;0.5 m以下夹矸对槽波的发育和能量成像影响不大;在煤厚相同的情况下,含夹矸层状模型相比不含夹矸层状模型的槽波主频低,槽波对煤厚2 m、夹矸厚度0.5 m以下的薄互煤层能够进行比较准确的探测。透射槽波可在薄互煤层中探测断距大于1/2煤厚的断层位置、走向及延展长度,可为西南地区薄互煤层中构造探查提供参考。      

陕西渭北煤田5#煤层粘土岩夹矸的研究

渭北煤田面积约１０万ｋｍ２。分布于太原组顶部５＃煤层中的粘土岩夹矸，上部层位分为两上分层，上分层夹矸厚度薄，下分层夹矸厚约０２ｍ，俗称“２００矸”；下部层位夹矸厚度变化较大。该文详细论述了粘土岩夹矸的岩矿特征。根据“２００矸”中含有副象β－石英、高透长石、锆石、磁铁矿等高温矿物组合，特有的粒序层理和岩性在全煤田十分稳定等特点，表明其原始物质来源于降落火山灰。根据ＴｉＯ２／Ａｌ２Ｏ３比值的明显变化，探讨了陆源组分的加入对火山灰蚀变粘土岩夹矸化学成分的影响。以“２００矸”为等时标志层，解决了５＃煤层在区域上的对比。     

用高岭石夹矸层对比茂名煤田煤层

我队在开展广东茂名煤田的普查勘探工作中,发现下第三系褐煤里具有一定对比特征的高岭石泥岩夹矸层。此种高岭石泥岩夹矸层在煤田中分布面积广,岩性特征明显,层位稳定,在煤田普查勘探中,凭它进行煤层对比,方法简单,依据可靠,从而解决了煤田煤层对比问题。      

煤层夹矸的褶皱成因

煤层中夹石层（夹矸）形状比较复杂,就岩性来说是多种多样的,常见的是粘土岩、炭质泥岩或粉砂岩,有时为石灰岩、硅质岩、油页岩、细砂岩甚至砾岩。一般认为,煤层夹矸是沉积过程中的夹层。是植物遗体堆积速度和沼泽水面上升速度之间出现“不足补偿”造成的,即“当沼泽水面上升速度大于植物遗体堆积速度时”,“沼泽水不断加深,沼泽环境发生变化,泥炭作用也就停止,代之以泥沙沉积物,形成煤层顶板或煤层夹矸”[1]。      

华北地区京西煤田侏罗纪煤层中伊利石矿物学特征及成因

为了探讨伊利石对煤化作用和沉积环境的指示作用，以华北地区京西煤田侏罗纪煤层夹矸为研究对象，采用X射线衍射方法（XRD）和X射线荧光方法（XRF）分别测定煤层夹矸的矿物组成和化学组成，研究夹矸中伊利石矿物学特征及成因。结果表明，京西煤田侏罗纪煤层夹矸主要由伊利石、绿泥石和石英组成，其中，伊利石质量分数平均为62.92%。将XRD数据和XRF数据进行对比分析，计算得到伊利石平均化学式为（K_0.37（NH₄）_0.03）Al₂（Si_3.60Al_0.40O₁₀）（OH）₂。京西煤田煤层夹矸中伊利石主要由高岭石转化而来，伊利石的NH₄+占层间阳离子的比例具有随沉积古盐度升高而逐渐升高的趋势，n（Si）/n（Al）Ⅳ具有随煤化程度升高而逐渐降低的趋势，这表明京西煤田侏罗纪煤层夹矸中的伊利石矿物学特征对沉积环境和煤化作用具有一定的指示作用。      

浅析贵州二叠系上统龙潭组27号煤层的聚煤规律

通过对27号煤层沉积背景、环境演化过程、分布特点、赋存状态、结构特点和煤厚变化特征进行分析，认为27号煤层主要沉积于海陆交互相环境，赋存在龙潭组中下部，厚0．1～4．8m，为薄-中厚煤层。该煤层在威宁-毕节以东、兴仁-贵阳-遵义以西范嗣内都有分布，夹石0～5层，～般为3层，向两南方向夹层增多。煤层厚度有北薄南厚、由西向东为薄-厚-薄的变化规律，六盘水煤田、织纳煤田为聚煤中心地带，     

复合煤层中夹矸对槽波探测解释断层落差的影响

槽波地震勘探技术在探测工作面内部断层、陷落柱发育情况、煤厚变化等方面已经取得较好的应用效果，现已成为井下地质构造探测的首选方法。但对于含夹矸的复合煤层地质构造的探测，槽波方法还存在一定的问题，为研究复合煤层中夹矸对槽波地震探测中断层落差解释的影响，通过建立不同的数值模型进行正演分析，并选取山西某矿复合煤层进行槽波探测试验。研究结果表明:复合煤层中的夹矸对槽波探测解释断层落差有较大影响，夹矸的厚度与煤层差异较小时，槽波探测解释断层落差时的单位煤厚标准应为复合煤层的总厚度；差异较大时，单位煤厚标准应为激发接收层的单一煤层厚度。研究结果可为槽波实际资料的解释、分析提供参考依据。      

Mercury in Western Canadian subbituminous coal—a weighted average study to evaluate potential mercury reduction by selective mining

Western Canadian subbituminous coal is mined using strip-mining methods. The coal is used to feed coal-fired power plants for electricity generation. Parameters that influence the mercury content of these coals include the occurrence and frequency of partings in the seam, weathering, and epigenetic mineralization. Most partings have higher mercury content than the coal layers in the same seam, with the single bentonite bed having the highest Hg content. However, some high ash components, such as sandy siltstone, do not follow this trend. The incorporation of the high mercury partings into the as-mined coal may increase the Hg content in the feed coal. Epigenetic mineralization may also increase the mercury content of coal, depending on the nature of the mineralization.Calculation of the weighted mean of mercury content for various combination of lithological components of a seam illustrates how these components influence the total mercury content of the seam. This approach also suggests how selective mining might be used to reduce mercury in “as-mined” coal.Results of weighted average calculations of mercury indicate that the thin lithological units with moderate mercury may not necessarily influence that overall weighted average of Hg for a seam. However, there can be exception, such as presence of thin (3.5 cm) bentonite parting with high mercury in a 94.5 cm seam that increased the mercury content of seam by 83.4%.     

Preparation and analysis of coal seam data utilizing paleoenvironment modeling,hazard #7 coal,Eastern Kentucky

Pennsylvanian strata of the Hazard coalfield, Eastern Kentucky, contain fluvial, upper-delta plain facies characterized by thick localized coals, bay-fill shales, levee silt- and sandstones, and channel-fill sands and gravels. Although the deltaic nature of these sediments has long been established, mining and exploration activities in the district require a thorough understanding of small areas within the delta environment. Coal quantity and quality trends in the Hazard #7 seam, the major producer in the area, have been examined in detail.The #7 coal accumulated in a peat swamp restricted laterally by a major fluvial channel. Three types of non-coal parting are recognized. Thin, tabular, fine-grained partings resulted from periods of increased terrigenous influx into the swamp. Lenticular crevasse-splay deposits locally split the coal. Wedge-shaped, fine- to coarse-grained partings, of probable levee origin, are found along the channel margin. Post-swamp deposits consist of thick bay-fill shales, thin shales, silt- and sandstones deposited on floodplains, and channel-fill sandstones and gravels.The modeling technique discussed provides guidance for mine development and regional exploration by prediction of coal seam quantity and quality trends from local geologic features. The thickest #7 coal is split by thin tabular partings and is overlain by thick shale sequences. Coal overlain by silt and sandstone is thinner and unsplit, and typically of higher heat value. Regional seam thinning due to channel scour is recognized. Factors which control the configuration of the coal seam include position within the peat swamp, proximity to the fluvial channel, swamp burial processes, and paleochannel sinuosity.     

Petrography and depositional conditions of the 64/65 coal seam in the Intrasudetic Basin,SW Poland

Variation in petrological composition of the coal of the 64/65 seam has been studied. Two types of vertical lithotype succession were distinguished. The first type is represented by bright lithotypes interlayered with clastic partings, while the second one shows a succession of lithotypes from bright to dull between clastic partings. The occurrence of these two types is believed to be the result of a different rate of subsidence. A trend of upward-decreasing vitrinite content has been observed in the seam with the second type of the vertical succession. This pattern was frequently interrupted by clastic partings. This tendency was not developed in the seam of the first succession type.On the basis of microlithotype and maceral composition it is found that the 64/65 seam represents a wide range of peat-forming environments from telmatic forest moor to open moor. Almost all bright-banded and banded coals were deposited in telmatic forest moor facies, while dull-banded coal, depending upon its petrographic composition, represents telmatic forest moor, telmatic reed moor, limno-telmatic forest moor and limno-telmatic reed moor. Dull coal represents only an open moor environment.Facial analysis of clastic sediments surrounding the seam revealed that there was a relationship between coal and clastic sedimentation. The features of the seam are strongly related to sub-peat topography, distance from active distributaries, and stability of the area.Sulfur and ash contents as well as character of clastic partings and petrology of the seam suggest conditions typical for groundwater and surface dominated swamps with pH a little higher than 4.     

龙口海域煤田地震资料夹矸异常分析

龙口煤矿主要为新生界古近系含煤建造,共含煤1、煤2、煤3、煤4四层煤,煤2为全区稳定可采煤层。以往的地震勘探剖面上反映煤2反射特征明显,断点干脆。在新采集的海上三维地震剖面上,煤2局部存夹矸,致使煤2反射波表现异常。通过正演模拟,总结出夹矸层厚度与频率的相互关系及其反射波特征。从实际资料的处理中,可以看出,经保幅处理后的叠前时间偏移剖面,比常规时间叠加剖面更能准确的反映出夹矸层的透镜体反射特征,特别是透镜体的上、下部同相轴反射波组强弱之分更加明显。实际采掘数据表明,地震剖面解释的夹矸分布范围,与实际情况吻合较好。     

鄂尔多斯盆地北缘延安组2号煤层稀土元素异常原因及其地质意义

鄂尔多斯盆地北缘延安组2号煤层稀土元素的异常原因一直存在着争议,以2号煤发育较完整的榆林大海则煤矿为例,运用电感耦合等离子质谱（ICP-MS）、扫描电子显微镜（SEM）等方法,分析煤及夹矸中稀土元素（REE）含量及其矿物学特征,并揭示稀土元素异常原因。结果显示:煤中总稀土元素（∑REE）含量为3.71~46.21 μg/g,轻稀土元素（LREE,La-Eu）比重稀土元素（HREE,Gd-Lu）更富集;稀土元素标准化配分模式图显示少数样品为Eu正异常;稀土元素含量较高的样品和拥有Eu正异常的样品主要分布在与夹矸距离较近的煤层中,表明煤中稀土元素分布受到了夹矸的影响;在夹矸中发现很多晶型较好的锆石、磷灰石、透长石及锐钛矿,这些矿物是在聚煤过程中接受火山物质的直接证据。综合认为,鄂尔多斯盆地延安组2号煤沉积期,盆地周缘存在一次火山活动,火山灰降落覆盖在泥炭沼泽之上,影响了聚煤作用,致使煤中稀土元素分布异常。研究结果解释了鄂尔多斯盆地北缘的煤中稀土元素异常原因,为研究区煤的加工利用方式提供参考。      

张家口市万全煤田煤层地下气化开发条件研究

根据万全煤田地质构造、水文地质、地层岩性、煤类与煤质、煤层(组)厚度与夹矸的具体分布特点，对万全煤田煤层地下气化开发条件及其前景进行了较为全面的分析和研究，对今后本区煤炭资源开发利用具有一定的指导意义。