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1.
样品采自伊敏褐煤盆地中一个因次火山活动形成的烟煤区,包含了从褐煤到瘦煤的变质系列。红外光谱分析表明,煤的含氧基团在褐煤阶段已开始消失,烷基和芳环同步增加,在R^O=1.10%时达最大值。顺磁共振自由其浓度和X-衍射参数La/Lc介于区域变质和岩浆接触热变质煤之间,芳核外官能团的热演化超前于芳核骨架及R^o的演化。  相似文献   

2.
用IR-1600系列傅利叶变换红外线分光光度计对腐植煤系列的褐煤、长焰煤、气煤、工、焦煤、瘦煤、贫煤和无烟煤煤样的镜质作了测定,共红外光谱特征反映了它们在变质程度上的区别。得出的镜质体芳核C=C键红外吸收波数随煤级变化曲线,反映腐植煤的芳核C=C键红外吸收波 随煤化程度增加而降低或向低波娄迁移的规律。有理由相信、腐植煤的煤化程度或牌号煤也可以用红我光谱方法精确确定。  相似文献   

3.
伊敏五牧场区煤质特征及变质规律   总被引:3,自引:0,他引:3  
陈冰冰  池海 《中国煤田地质》2005,17(5):34-36,86
伊敏五牧场区存在着从褐煤到贫煤完整的变质系列,其主要煤变质类型为接触变质.在本区煤系地层底部有一酸性侵入岩体,该侵入岩体是引起本区煤变质的直接热源,它提供了褐煤向烟煤转化的热动力.本区出现的隐爆角砾岩也是受热不均匀或热叠加造成煤类复杂多变的原因.区内构造十分发育,构造条件是煤变质的又一主要因素.研究该区煤变质规律对伊敏煤田及海拉尔褐煤盆地烟煤预测具有指导作用.  相似文献   

4.
中国煤的叠加变质作用   总被引:12,自引:0,他引:12  
杨起 《地学前缘》1999,6(Z1):1-8
中国煤变质具有多阶段演化与多热源叠加变质的特点;部分中国煤经历过3个变质演化阶段:以深成变质作用为主的第1演化阶段。以多热源叠加变质作用为特征的第2演化阶段和以奠定煤变质格局为主的第3演化阶段。除煤的深成变质普遍存在外,区域岩浆热变质为另一种中国煤的主要变质模型;多热源叠加变质是中国大多数中、高煤级煤产生的主要原因,其中区域岩浆热变质作用的影响最显著;中国煤的叠加变质作用主要发生在第2演化阶段;文中归纳出5种叠加变质作用类型。  相似文献   

5.
区域岩浆热变质作用及其对我国煤质的影响   总被引:5,自引:0,他引:5  
本文根据中国煤变质的特点分析了促使煤变质演化的地质条件,阐述了接触变质作用和动力变质作用的局限性,主要是深成变质作用使中国煤演化到低变质阶段,燕山期岩浆活动导致的区域岩浆热变质作用弥补了这一缺点,使很大一部分中国煤增高了煤级,形成了储量丰富,多用途的中、高变质煤。并根据岩浆性质、侵入规模、侵入层位和深度以及沉积盖层的封闭程度对区域岩浆热变质作用进行分类,划分出三个亚型:深成岩浆热变质作用、中深成岩浆热变质作用和浅成岩浆热变质作用,总结了区域岩浆热变质作用的鉴定特征及其对中国煤质的影响。  相似文献   

6.
杨起教授     
杨起院士长期从事煤地质学、煤沉积环境、煤变质作用、盆地热史演化、煤聚积规律等的教学和研究工作,近期又拓宽至煤中有害物质、燃煤污染和煤层气温地质的研究。他和课题组针对我国一些煤层的盖层较而煤胡却高的特征,提出了中国煤的多阶段演化与多热源叠加变质的理论,提出中国部分煤的煤胡高是深成变质煤叠加了以区域岩浆热变质为主或其它类型变质作用的结果,并认为中国煤极总估自北向南自西向东增高的规律主要是太平洋板块古向俯冲的影响。上述理论对我国煤田预测、煤盆地有机质热演化、煤层气选区评价、煤成烃成困和赋存规律的古代有…  相似文献   

7.
华北晚古生代煤变质演化及煤质预测   总被引:1,自引:0,他引:1  
华北晚古生代煤具有中部和南部变质程度较高而南部边缘和北部低的特点。这是华北晚古生代经历了3个阶段变质演化的结果。华北地台稳定阶段除个别地区外,深成变质作用使绝大多数晚古生代煤只演化到低变质阶段;地台活化早期叠加的区域岩浆热变质作用造成部分低煤级媒提高到中、高变质阶段;地台活化晚期紫荆关断裂的右旋移动奠定了华北晚古生代煤变质分布的格局。根据岩浆性质、侵入规模等特点将区域岩浆热变质作用划分为3个亚型。区域岩浆热变质煤的分布受燕山期岩浆沿一定方向断续侵入的控制。从成因上阐述区域岩浆热变质作用的主要特点。基于地质因素分析和煤变质作用类型预测华北晚古生代煤级分布,新的预测增加了炼焦煤的储量,且部分已被钻探证实。  相似文献   

8.
作者对采自霍林河南露天矿14层、17层褐煤的4个样品粉碎过40~80目分别地处理,经干体系热模拟实验,计算出露林河煤田煤变质作用中温度与R_(0.max)、压力与R_(0,max)自然界的与人工煤变质作用关系。认为经人工处理的褐煤,可在低压条件下,温度达450℃时,就具有焦煤性质。  相似文献   

9.
南票热变煤中不溶有机质的谱学研究   总被引:1,自引:0,他引:1  
通过对南票热变煤的Ⅰ·R、Rock—eval与XRD的研究,对其成煤母质、煤级、矿物与热变煤的物理化学结构演化等方面有了新的认识:该煤生成有低等生物参与;煤脱矿作用使脂肪结构优先低温氧化,煤中矿物对S2峰影响较大;Tmax、TPI、OPI、d002、Lc等为较好的成熟度参数,而HI、A因子、C因子、脂芳比受成熟度与母质双重因素影响;d002、Lc与温度和有机质受热速度有关;镜质体反射率主要取决于稠环芳香结构规整程度;La、Lc下降与La/Lc>1是热变煤特征;热变煤的物理化学结构演化类似区域变质煤。  相似文献   

10.
湘赣中南部地区煤的岩浆热变质作用   总被引:6,自引:0,他引:6  
潘伟尔  杨起 《现代地质》1993,7(3):326-336,T002
湘赣中南部地区的煤主要是高变质煤。虽然深成变质作用存在,但煤本身变化显著,煤与石墨、天然焦同层异矿,煤层围岩蚀变和煤变质带展布与侵入岩体及火山岩的分布密切相关等,都证明岩浆热变质作用是湘赣中南部地区煤变质作用的主要类型。印支—燕山期的岩浆活动形成广阔的高温区,从而形成这一地区大量的高变质烟煤和无烟煤。侵入岩体周围形成煤变质正向环带,岩体群之间则形成反向环带;接触带煤变质呈现向石墨或天然焦两个不同的演化方向;叠加在深成变质作用基础上的岩浆热变质作用控制了这一地区煤变质带展布的格局。  相似文献   

11.
准噶尔盆地南缘煤成油的地球化学特征   总被引:3,自引:3,他引:3  
齐古油田的原油来源于准噶尔盆地南缘中、下侏罗统的煤系地层.具有饱和烃与芳烃含量高,Pr/Ph>2.5的特征.原油与母岩的碳同位素组成有较好的一致性,都富集重组分.色质分析结果表明,离子特征峰具有典型陆源高等植物输入的标志.泥岩有机质的显微富氢组分占20%以上,它们富集于河流三角洲和水下冲积扇等地.在弱还原-还原环境的低演化阶段形成天然气,也能形成石油,在该盆地沿边缘呈带状分布。  相似文献   

12.
The judicious choice of dipolar dephasing times or carbon magnetization holding times has been shown to improve resolution in solid state nuclear magnetic resonance (NMR) spectra of complex materials. Signals from protonated and alkylated aromatic carbons are reduced to enhance resolution of aromatic oxygenated groups. Rapidly rotating methyl groups can be resolved from other aliphatic carbon types. These techniques were used to investigate the structure of a brown coal, xylite fractions of a brown coal, a bituminous coal, an oil shale and a solvent-refined coal. The results allow estimates of the fraction of aromatic carbon that is protonated in coal to be made, and demonstrate that methyl groups in coal rotate rapidly at room temperature.  相似文献   

13.
选择四个不同变形程度的中阶煤样品作为研究对象,通过开展煤样的等温CH4吸附/解吸实验、X射线衍射(XRD)和傅里叶变换红外光谱(FT-IR)测试分析,研究了构造煤等温吸附/解吸性随煤变形程度的演化特征及其地球化学机理.结果表明,构造煤等温CH4吸附和解吸曲线随压力升高均呈现先快速增大后逐渐稳定的变化趋势,符合I型等温线...  相似文献   

14.
Three Australian brown coals have been separated into humin and humic acid fractions and studied by high resolution solid state 13C NMR spectroscopy and Fourier transform IR spectroscopy. The aromatic rings of the humic acids are highly substituted showing that extensive cross linking must have occurred during formation from wood lignin and tannin. However, the humins contain more aliphatic carbon and hydrogen than the corresponding humic acids. This shows that little cross linking has occurred with other components of the brown coal such as resins, waxes cutin and algal detritus, and cross linking has not rendered the aromatics alkali insoluble. The kinetics of extraction are complex and not simple first order. This is reflected in the chemical composition of the humic acid which is extraction temperature dependent. We also observed that there is a conversion of aromatic carbon to aliphatic carbon and gas during extraction, probably by alkaline oxidation, resulting in ring opening. A range of suitable model compounds have been studied to confirm this finding. Such a mechanism may account for the modification of lignin in oxidising environments such as those occurring in the initial stages of coalification (lignite or brown coal formation) and in soils.  相似文献   

15.
Cyclic terpenoids present in the solvent extractable material of fossil woods, ambers and brown coals have been analyzed. The sample series chosen consisted of wood remains preserved in Holocene to Jurassic sediments and a set of of ambers from the Philippines (copalite), Israel, Canada and Dominican Republic. The brown coals selected were from the Fortuna Garsdorf Mine and Miocene formations on Fiji.The fossil wood extracts contained dominant diterpenoid or sesquiterpenoid skeletons, and aromatized species were present at high concentrations, with a major amount of two-ring aromatic compounds. Tricyclic diterpenoids were the predominant compounds in the ambers. Aromatized derivatives were the major components, consisting of one or two aromatic ring species with the abietane and occasionally pimarane skeletons. The saturated structures were comprised primarily of the abietane and pimarane skeletons having from three to five carbon (C1, C2, etc.) substituents. Kaurane and phyllocladane isomers were present in only minor amounts. Bicyclic sesquiterpenoids as saturated and partial or fully aromatized forms were also common in these samples, but only traces of sesterterpenoids and triterpenoid derivatives were found.The brown coal extracts were composed of major amounts of one- and two-ring aromatized terpenoids, with a greater proportion of triterpenoid derivatives than in the case of the woods and ambers. This was especially noticeable for the German coal, where the triterpenoids were predominant. Open C-ring aromatized structures were also present in this coal. Steroid compounds were not detectable, but some hopanes were found as minor components in the German brown coal.An overview of the skeletal structure classes identified in each sample, as well as the general mass spectrometric characteristics of the unknown compounds are included in the present paper. It can be concluded from these structural distributions that aromatization is the main process for the transformation of terrestrial cyclic terpenoids during diagenesis, constituting a general pathway for all terpenoids.  相似文献   

16.
The paper presents the results of petrographic and chemical investigations of xylitic coal, xylite and their ash. As is known, a xylitic coal has the function of a lithotype whereas xylites are inclusions brown coals only. All these xylites were arranged according to the increasing degree of doppleritization of xylem in the sequence: common xylite, poorly, moderately and intensely doppleritized varieties, dopplerite coal. The distinctive criteria were their differentiated physical properties, which are also reflected in the variable petrographic and chemical compositions. The petrographic differences result from the replacement of textinite by ulminite and gelinite, while the differentiation of the chemical constitution is due to the increasing carbon content and the increasing number of functional groups that determine the aromatic nature of the internal structure of the coal. Infrared absorption spectroscopy, Raman spectroscopy and chemical analysis of ash have shown that the aromatization of coal and the resulting increase in the degree of order of the structural unit are due to the formation of organomineral compounds in the course of doppleritization. It appears from the investigations that the doppleritization of vegetable matter gives rise to gels that are a mixture of organo-mineral humic compounds. The process of humification leads to the formation of gel made up of humins. It follows then that there are two ways of initial coalification of plant material, both referred to as biochemical gelification.  相似文献   

17.
利用傅立叶变换红外光谱(FTIR)分析技术,对乌达矿区低温氧化和新鲜煤样进行了红外光谱测试,通过两类煤样的特征官能团吸光度的对比分析.揭示了煤在氧化前后特征官能团的变化规律:氧化后的煤样中脂肪族和芳烃CH减少,酸酐C=O从无到有,芳烃骨架C=C基本不变,进而研究了其对煤自燃倾向性的影响。结果表明脂肪族和羟基含量越高,煤自燃倾向性越大。  相似文献   

18.
Analysis of the tri- and tetraaromatic hydrocarbon fractions of a brown coal sample from the Latrobe Valley, Victoria, Australia indicate the predominance of pentacyclic hydroaromatic components. Many of these have not been previously reported in the literature, but are obviously diagenetically related to triterpenoids naturally occurring in the biosphere. The components whose molecular structures have been confirmed, together with those for which tentative structural assignments are given, offer strong support for a theory of progressive diagenetic aromatization of C-3 oxygenated triterpenoids, commencing from ring A. Other compounds present in smaller amounts suggest that 1,2-methyl shift reactions also occur prior to or during aromatization. There is a notable absence of polycyclic aromatic hydrocarbons (PAH's) which can be diagenetically related to the steroid or extended-side-chain hopane skeletons.  相似文献   

19.
华北板块大羽羊齿植物的成煤古气候含义   总被引:4,自引:0,他引:4  
华北板块存在3个大羽羊齿分布区:Ⅰ—大羽羊齿植物贫乏区;Ⅱ—Gigantonoclea分布区;Ⅲ—Gigantonoclea—Gigantopteris共存分布区。根据大羽羊齿植物的地理限制、叶相特征和其他标志重建了华北板块早二叠世晚期至晚二叠世早期的古气候分带格局:其东南部(Ⅲ区)处于无季节性分化的热带雨林气候,并逐渐向西北过渡为萨旺纳气候(Ⅱ区)和热带草原气候(Ⅰ区)。上述古气候分带的现今取位方向(北东向)是华北板块于二叠纪的北向漂移过程中,伴随35°~45°逆时针旋转造成的。正是这种运动机制,使得华北板块逐渐脱离赤道附近的热带雨林成煤气候带,导致早二叠世早期广泛存在的聚煤作用,在早二叠世晚期—晚二叠世早期收缩至现今华北地台的东南一隅。   相似文献   

20.
滇西褐煤伴生元素锗的富集及评价   总被引:6,自引:0,他引:6  
阐述了滇西褐煤中锗富集规律及其评价方法和回收利用等问题。指出在滇西122个第三系聚煤盆地中,仅有几个矿区褐煤中富锗,而它们仅分布在澜沧江以西大片花岗岩出露区,可见富锗煤矿区只在特定的地球化学环境中才能形成。含锗价值较大矿区在富锗段最小勘探网度应不小于100m,进一步圈定留待开采过程中加密取样。在充分利用了煤的热值后,应在烟尘及煤灰中回收锗,吨煤中锗的价值比煤本身高得多。  相似文献   

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