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1.
通过研究无烟煤层中泥岩夹矸的岩石矿物学特征，探讨其主要成分高岭石发生转化的主要方向及影响因素。对晋城矿区实地观测，并采集一定量的标本，通过显微镜下鉴定、差热分析、X射线粉晶衍射分析、红外吸收光谱分析等研究，发现无烟煤层泥岩夹矸中高岭石主要向伊利石转化，并有伊利石-蒙脱石(I／M)混层矿物及蒙脱石出现。煤的变质程度升高、夹矸矿物转化的主要原因是区域变质作用及周围介质条件的影响。 相似文献
2.
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（K0.37（NH4）0.03）Al2（Si3.60Al0.40O10）（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。 相似文献
3.
通过研究无烟煤层中泥岩夹矸的岩石矿物学特征,探讨了其主要成分高岭石发生转化的主要方向及影响因素。通过样品的显微镜下鉴定、差热分析、X射线粉晶衍射分析、红外吸收光谱分析等一系列测试结果的分析研究,发现无烟煤层泥岩夹矸中高岭石因受不同因素的影响而发生不同的转化,即:高岭石向伊利石转化,伊利石-蒙脱石(I/M)混层矿物及蒙脱石出现。其主要原因是区域变质作用及周围介质影响所致。 相似文献
4.
5.
无烟煤泥岩夹矸的岩石矿物学特征及其研究意义 总被引：2，自引：0，他引：2
对山西晋城矿区3号无烟煤层进行了实地观测，采集了一定数量的标本，通过显微镜下鉴定、差热分析、X射线粉晶衍射分析、红外吸收光谱分析等一系列测试手段对无烟煤层中泥岩夹矸的岩石矿物学特征进行了研究，对其主要成分高岭石发生变化的主要原因及影响因素进行了探讨。结果发现，无烟煤层中泥岩夹矸的主要成分高岭石因受不同因素的影响而向不同方向发生转化，主要表现在高岭石向伊利石转化，并有伊利石-蒙脱石(I/S)混层矿物及蒙脱石出现。造成这种煤的变质程度升高而其夹矸成分转化的主要原因可能是区域变质作用及周围介质条件影响所致。 相似文献
6.
《矿物岩石地球化学通报》2015,(4)
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。 相似文献
7.
文章以沁水煤田长治首阳山矿15号煤为研究对象,运用电感耦合等离子体质谱(ICP-MS)和X射线荧光光谱(XRF)等方法对煤中的稀土元素进行测试和分析。探讨了15号煤中稀土元素的富集机理、配分模式、赋存状态以及成煤环境等地球化学特征。结果表明:(1)研究区煤层中的稀土元素含量均值为49.28μg/g,整体含量较低;(2) 15~#煤(除SYS15-2外)和夹矸中稀土元素均为轻稀土富集型(LREY),并且夹矸中轻稀土富集更加明显;(3)稀土元素主要赋存在黏土矿物中;(4)成煤环境整体上以弱还原环境为主,稀土元素物质来源主要为陆源碎屑。 相似文献
8.
华北石炭二叠纪煤层含铵云母粘土岩夹矸研究 总被引：5，自引：3，他引：5
含铵云母粘土岩夹矸被广泛分布于华北石炭二叠纪聚煤区太原组及山西组煤层中，其可划分为６种类型。文章详细描述了岩石的特片和铵云母在粘土岩夹矸中的赋存特点，测试结果表明铵云母均为１Ｍ型铵云母，它们是由成煤植物和有机质降解形成的ＮＨ＾＋４离子，促使煤层粘土岩夹矸中的高岭石，伊利石在约１２０℃的酸性条件下转化成的。这种铵云母可以作为煤成气生成和储集的指示矿物。 相似文献
9.
鲁西南煤夹矸的矿物学特征研究及应用前景 总被引：3，自引：1，他引：3
对鲁西南上石炭统11层煤和7层煤夹矸的化学成分和矿物学特征进行了研究，结果表明，这两层煤夹矸属于硬质高岭土，成分接近于纯净的高岭石，伴生有石英、黄铁矿、少量长石及微量锆石和磷灰石等矿物。光学及扫描电子显微镜、X射线衍射分析和红外分析等系统性研究的结果表明，高岭石主要有两种存在形式，一种呈蠕虫状集晶，另一种是隐晶质或胶状高岭石，测得其结晶指数分别为0．54—0．74和0．47—0．53，说明其有序度偏高；化学分析结果表明，其化学成分接近于高岭石的理论值，A1203含量达35％—37％，Si02含量为47％—48％，碱金属、碱土金属及其他氧化物含量很低。高岭石泥岩夹矸的矿物、化学成分及工艺物理性能表明：它是一种开采成本低、利用价值高的高岭土资源之一，不仅可作为优质陶瓷原料用来生产长石质瓷，也可用于生产聚合铝及4A分子筛，并且在矿物填料和其他工业部门也有广阔的开发应用前景。 相似文献
10.
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。 相似文献
11.
Stukalova I. E. Petrova V. V. Sakharov B. A. Pokrovskaya E. V. 《Lithology and Mineral Resources》2001,36(3):243-254
The rare mineral, potassium tobelite being the NH4-bearing mica, was first described in Lower Carboniferous coal-bearing rocks of the Egorshin–Kamensk district on the eastern slope of the Urals. It was formed from kaolinite and pyrophyllite at temperature less than 500°C and pressure about 2000 atm. The formation of tobelite was probably favored by postsedimentary stresses. Owing to sharp increase in pressure, gases were released from organic matter of the coal-bearing sequence and transformed into ammonia, which was subsequently incorporated as NH+
4in the structure of clay minerals. The potassium tobelite is an indicator of high-grade metamorphism (up to anthracite rank) of the organic matter in coal-bearing sequences. 相似文献
12.
Burial Metamorphism of the Ordos Basin in Northern Shaanxi 总被引：1，自引：0，他引：1
Zhang Lifei 《《地质学报》英文版》1993,67(2):181-193
Burial metamorphism has been found in the Ordos basin of northern Shaanxi. On the basis of a rather intensive study of burial metamorphism of sandstone, it has been shown that the evolution from diagenesis to metamorphism involves four stages: cementation of clay minerals, regrowth of pressolved quartz and feldspar, cementation of carbonates and formation of laumontite. On that basis it has been put forward that the laumontite is formed by burial metamorphism of clay and carbonate minerals. According to the thermodynamic data of minerals, the conditions under which laumontite is formed are T<250℃ and X_(CO_2)<0.17. High-resolution SEM and TEM studies of clay minerals in mudstone show that there occur a mixed layer assemblage of bertherine and illite/chlorite and transformation from bertherine to chlorite. On that basis coupled by the X-ray diffraction analysis the author suggests the following transformation of clay minerals during burial metamorphism: the earliest smectite-kaolinite assemblage changes into the bertherine-illite mixture with increasing depth, then into the illite/chlorite mixed layer assemblage and finally into dispersed individual illite and chlorite. The reaction of the transformation is:smectite+kaolinite+K~+=illite+chlorite+quartz According to the study of the oxygen isotope thermometry of the coexisting illitequartz pair, the temperature of the above transformation is lower than 180℃. 相似文献
13.
《Applied Geochemistry》2004,19(9):1495-1503
Compositional data from published sources, environmental monitoring and new analyses demonstrate that for a wide range of water types (oilfield water, coal mine water, landfill leachate) NH4+ is present in amounts up to 2200 mg/L. Oilfield waters from Alberta, Canada contain 1–1000 mg/L NH4+, coal mine water (UK) surface discharges 1–45 mg/L NH4+, and landfill leachates (UK) up to 2200 mg/L NH4+. Ammonium contents generally show a positive correlation with K, and increase with increasing salinity. Geochemical modelling of sufficiently complete data using SOLMINEQ88 demonstrates that NH4+ activities vary systematically, and are consistent with a mineralogical control. Sodium–K exchange divides the entire sample suite into at least 4 groups, controlled by reaction temperature and reaction with either albite/K-feldspar or illitic clay minerals. In contrast, comparison of NH4+ and K divides the sample suite into 2 groups. On the basis of geological setting, these correspond to K–NH4+ exchange involving illitic (illite-muscovite) clays (and possibly feldspars) for samples from natural sources, and to exchange involving smectitic clays for samples from landfill sites. This study demonstrates the importance of NH4+ as a constituent of natural groundwaters, requiring that this reservoir of N is taken into account in detailed discussion of hydrological components of the N cycle. 相似文献
14.
Rare metals in coal deposits have attracted much attention in recent years because of their potential economic significance. This paper reports the abundance and enrichment origin of rare metals in the Late Permian coals (K1 and K2 Coals) of the Moxinpo Coalfield, Chongqing, southwestern China. The K1 Coal is characterized by highly-elevated concentrations of U-Re-V-Cr-Se and Nb(Ta)-Zr(Hf)-REE assemblages; the latter assemblage is also enriched in the K2 Coal. The high temperature ash (815 °C) of the K1 Coal is enriched in V, Cr, Se, Re, U and REE; the ash of the K2 Coal, and also the floor strata of each seam, are enriched in REE, potentially making all of the units economically viable sources for these elements.The minerals in the K1 Coal are mainly represented by kaolinite, illite and mixed-layer illite/smectite, and pyrite, while the minerals in the K2 Coal consist mainly of kaolinite and tobelite [(NH4,K)Al2(AlSi3O10)(OH)2]. Authigenic roscoelite [K(V3 +,Al)2(AlSi3O10)(OH)2] is commonly observed in the K1 Coal under the SEM, and was probably formed by interaction of kaolinite with V derived from permeating U-Re-V-Cr-Se-rich solutions during early diagenesis. The tobelite enriched in the K2 Coal was formed by reaction between kaolinite already present in the coal and NH4 + derived from decomposition of the organic matter during hydrothermal alteration at a relatively high temperature.The mafic tuffs directly underlying the K1 Coal and containing limestone residual breccias not only served as the substrate for coal accumulation but also as the source of sediment from the uplifted areas around the coal basin. The latter is indicated by low Al2O3/TiO2 ratios (from 10.09 to 14.24), positive Eu anomalies enrichment of medium rare earths (relative to upper continental crust), and detrital calcite of terrigenous origin. The highly-elevated concentrations of U-Re-V-Cr-Se assemblages in the coal were derived from exfiltrational hydrothermal solutions and were then deposited in a euxinic environment. The terrigenous materials in the K2 Coal, however, were derived from felsic-intermediate rocks at the top of the Kangdian Upland, although the elevated concentrations of Nb(Ta)-Zr(Hf)-REE assemblages are attributed to the input of hydrothermal solutions. 相似文献
15.
全风化花岗岩化学及矿物成份在全土和粘粒中的不同表征 总被引：1，自引：0，他引：1
对全风化花岗岩化学和矿物成份的测试常用全土和粘粒部分(粒径<2μm)分别进行。业已发现两者由于物质组成和结构特征的差异,对土工程地质性质所起作用不同。本文给出了6个全风化花岗岩样品的全土和粘粒部分筛分法和移液管法测定粒度成份,用X荧光光谱仪做全量化学分析,及XRD矿物学分析的结果。对比这两部分数据发现,属于含砾土的这些样品化学成份的变化同矿物一致,尤其是同粘土矿物成份含量变化很一致。同全岩相比,粘粒化学成份中的SiO2减少了近50%,K2O含量也降低,而Al2O3、Fe2O3和H2O+都明显升高。粘粒中氧化物相对含量升高者居多;全岩矿物成份以石英、粘土矿物和长石为主,粘粒中埃洛石和高岭石占大多数,其次为伊利石;粒度成份、化学成份和矿物含量相关性比较明显的是:石英和角砾正相关,和砂粒负相关,长石和砂粒正相关,粘土矿物含量和Al2O3、烧失量(LOI)和埃洛石含量正相关。 相似文献
16.
针对赣南风化淋积型稀土矿中稀土元素的分异现象,通过研究该稀土矿的主要矿物成分——高岭石和埃洛石-7的矿物特征及其在不同条件下的吸附特征,探讨了该类型稀土矿的成矿机制和稀土元素分异机理。高岭石和埃洛石-7吸附稀土元素的能力受体系p H值以及金属阳离子钾、钠的的影响,且埃洛石-7吸附稀土元素的能力高于高岭石。横向对比实验结果表明当体系中赋存有K+时,两种粘土矿物对稀土元素的吸附呈现出分化趋势,其中高岭石主要吸附中-重稀土元素,埃洛石-7反之,因此风化淋积型稀土矿风化过程中释放出的K+可能会使高岭石和埃洛石-7呈现出差异吸附特征,进而反过来影响稀土矿中稀土元素的配分。 相似文献
17.
In the process of steam stimulation exploitation of viscous crude oil, the injected water, at high temperature and under high pressure, reacts intensively with the host rock. This kind of water–rock interaction in Liaohe Shuguang Oil Field was studied on the basis of analysis of water composition changes, laboratory experiments, mineral saturation indices analysis, and mass balance calculation. Compared with the injected water, the changes of the composition of discharged water are mainly the distinct decrease of pH, Na+, SiO2 and Cl−, as well as the increase of K+, Ca2+, Mg2+, SO
4
2−
and HCO
3
−
. Laboratory experiments under field conditions showed: the dissolution sequence of minerals quantitatively is quartz>potassium feldspar>albite, and the main change of clay minerals is the conversion of kaolinite to analcime. Mass balance calculation indicated during the process of steam stimulation, large quantities of analcime are precipitated with the dissolution of large amounts of quartz, kaolinite, potassium feldspar, and CO2. These results correlated very well with the experimental results. The calculated results of Liaohe Shuguang Oil Field showed that during the steam stimulation for viscous crude oil, the amounts of minerals dissolved (precipitated) are huge. To control the clogging of pore spaces of oil reservoirs, increased study of water–rock interaction is needed. 相似文献
18.
Isotopic composition of salt efflorescence from the sandstone castellated rocks of the Bohemian Cretaceous Basin (Czech Republic) 总被引：1，自引：0，他引：1
The origin of sulphates in sulphate-rich efflorescences on quartz sandstones with a clay matrix, exposed in rural areas of
the Czech Republic is interpreted, based upon an isotopic study of S and O. Sulphates such as gypsum and/or alums exhibit
δ34S ranging from +1.3 to +6.1‰ and δ18O from +5.3 to +8.8‰. The low variability of S and O isotopes indicates a common source of the sulphur and a similar mode
of sulphate formation. Atmospheric sulphates with a similar isotopic signature occur in the area, due to the combustion of
sulphurous coal in power plants, located a few tens of kilometres from the sampling points. The sulphates crystallize from
supersaturated pore waters that represent atmospheric precipitation, rich in sulphates, having percolated through the porous
sandstone system. The previously proposed model of efflorescence growth (that it is due to the oxidation of pyrite) can be
excluded, due to both the rare occurrence of pyrite and also to its different isotopic signature (δ34S about −22‰). Although gypsum prevails in the central and eastern part of the studied area, the north and north-west of the
Bohemian Cretaceous Basin (the most polluted region) exhibits a significant presence of alums (NH4
+ or K+−NH4
+-rich). Formation of alums can be explained by the partial dissolution of clay minerals or feldspars present in the sandstone
matrix. Release of alumina from these phases is facilitated by the low pH of the precipitation (pH 4–4.5) and also locally
by organic acids, traces of which were found in the studied efflorescences by the use of infrared spectroscopy. 相似文献
19.
20.
The mobility of strontium in subsurface is largely influenced by sorption on to clay minerals. In the present study, kaolinite
clay samples collected from the Kalpakkam nuclear plant site were employed to understand the sorption characteristics of strontium
by batch method. The effect of several parameters such as time, strontium ion concentration, pH, temperature and ionic strength
was investigated. The kinetic studies suggested pseudo-second-order mechanism. The experimental sorption data was fitted to
Langmuir adsorption model for obtaining the sorption capacity of the sorbent. The maximum sorption capacity was 5.77 mg/g
at 298 K and was found to increase with an increase in temperature. It was observed that the distribution coefficient (K
d) of strontium on clay increased as the pH of the solution increased. The distribution coefficient was found to decrease with
an increase in concentration of Na+ and Ca2+ ions. This variation of K
d suggests that cation exchange is the predominant sorption process. It was also observed that sorption process is endothermic.
The thermodynamic parameters such as ∆G
0, ∆H
0 and ∆S
0 were calculated. The negative values obtained for ∆G
0 indicated that the sorption of strontium on clay was spontaneous at all studied concentrations. ∆G
0 becomes more negative with an increase in temperature, suggests that the sorption process is more favorable at higher temperatures. 相似文献