共查询到18条相似文献，搜索用时 265 毫秒
1.
新疆准东煤田五彩湾矿区西山窑组煤层厚度稳定,分布广泛,煤质优良.笔者从成因角度运用煤田地质学、煤岩学、煤地球化学及沉积学等,进一步探讨西山窑组巨厚煤层煤岩组分特征、煤相类型.结果表明,煤层微观煤岩以镜质组为主,惰性组次之,含少量壳质组.相学分析表明,该区聚煤沼泽类型以湿地森林沼泽相为主,干燥森林沼泽相次之.少数样品指示成煤过程中短时期、周期性深覆水或开阔水域沼泽相存在.煤相分析显示威煤环境具网状河三角洲沼泽相沉积特征.煤岩和煤相分析为聚煤环境分析、煤质评价和预测、煤的可选性评价等提供科学依据. 相似文献
2.
3.
应用煤岩学、煤化学、煤地球化学理论以及多种煤相学的参数及其组合对新疆准东煤田五彩湾矿区ZKL805钻孔西山窑组巨厚煤层进行了煤岩煤质、煤相特征及成煤环境分析,并在巨厚煤层内部识别出了若干水进水退含煤小旋回。该巨厚煤层宏观煤岩类型以暗淡型煤为主,其次为半亮型煤及半暗型煤。煤层有机显微组分组总体以惰性组含量占优势,镜质组次之,壳质组含量极低。煤相类型主要为干燥森林沼泽,其次为潮湿森林沼泽。依据煤相参数的垂向演化,巨厚煤层内部识别出4个水进型、4个水退型及1个加积型含煤小旋回。巨厚煤层形成于覆水较浅、水体活动性较弱的稳定泥炭沼泽环境,垂向上由这些水退水进含煤小旋回叠加构成。 相似文献
4.
《中国煤炭地质》2015,(8)
以大同煤田王坪井田太原组8号煤层为研究对象,采用光学显微镜、煤质分析、电感耦合等离子质谱(ICPMS)和X射线荧光光谱(XRF)等方法探讨了其煤岩学、煤质和煤地球化学特征,并在此基础上分析了其煤相特征。结果表明:(1)王坪井田太原组8号煤层宏观煤岩类型为半亮煤和半暗煤,显微组分以镜质组和惰质组为主,显微煤岩类型为微暗亮煤和微亮暗煤;(2)8号煤为低水、中低灰、中低硫和中高挥发分气煤;(3)煤层顶部和底部属于陆相-过渡相,其余分层为海相-过渡相;(4)成煤环境为三角洲平原的泛滥盆地,煤相基本为开阔水域沼泽相,部分为湿地草本沼泽相;煤层自下而上经历了水位升降两个过程,并由于水位过深发生一次煤层聚集间断,反映了沼泽环境及成煤植物的演化规律。 相似文献
5.
6.
7.
塔里木盆地东南缘下—中侏罗统煤层沿阿尔金山前断续分布,其煤岩、煤质与典型的西北侏罗纪煤层具有明显不同。通过对和田布雅、于田普鲁、且末红柳沟等煤矿主采煤层样品进行煤岩、煤质鉴定及煤化指标等一系列综合研究分析,结果表明,主采煤层以光亮煤、半亮煤为主,其次是半暗煤、暗淡煤;煤岩组分以镜质组为主,壳质组含量少,具中-高镜惰比。因成煤沼泽的还原程度促进了无机硫分的形成,煤中全硫含量随镜质组含量的增加呈现逐渐增高的趋势,且煤层硫分与灰分整体具有明显的负相关关系。此外,煤层挥发分受不同种类硫分的影响,亦有明显差异性变化。在民丰凹陷中-高硫煤中,硫分以无机硫为主,随着硫分的升高挥发分亦有升高趋势;瓦石峡凹陷中-低硫煤受有机硫控制,对挥发分产率的影响不明显。民丰凹陷煤层的灰分指数高于瓦石峡凹陷,可见后者的成煤沼泽环境潜水面要比前者高得多。针对上述诸多因素分析,进一步揭示塔东南地区煤岩、煤质多样性变化受断陷湖盆以及局部水体较深的还原型沼泽环境控制,最终形成了中-高挥发分、中-低灰分、中-低硫分的煤质及富镜贫惰的煤岩特征。 相似文献
8.
9.
10.
《新疆地质》2020,(3)
为了揭示潘吉塔格矿区不同煤岩煤质形成条件及其垂向变化特征,探讨该区煤岩煤质与成煤环境的关系,采用煤岩学和地球化学等方法,基于对主采煤层样品煤岩鉴定、工业分析及灰成分指标等数据分析,研究结果表明:该煤矿主要煤层以半亮型煤为主,富镜质组、贫惰质组,煤质呈低灰、低硫、高挥发分特征,煤灰成分以SiO2为主,煤变质阶段较低,煤类均属长焰煤。煤层由深至浅垂向演化呈镜惰比由小到大,灰分由高变低,挥发分由低变高,硫含量先增大后减小再增大,成煤环境由弱氧化-还原型到还原型的变化趋势。综合分析表明,研究区中—下侏罗统主要煤层形成于湖泊-三角洲淡水沉积环境,具陆相成煤特征,成煤环境温暖潮湿。其中西山窑组煤岩煤质特征与八道湾组有显著区别,成煤环境迥异。 相似文献
11.
Weihua Ao Wenhui Huang Chengmin Weng Xiuling Xiao Dameng Liu Xiuyi Tang Ping Chen Zhigen Zhao Huan Wan Robert B. Finkelman 《地学前缘(英文版)》2012,3(1):85-95
Multiple sets of thick coal beds characterized by simple structure and shallow burial depth were developed in the Early and Middle Jurassic strata of the Ordos Basin,northwestern China.The huge reserves of this high quality coal have a high commercial value.We studied the coal’s petrologic characteristics and its maceral distribution to determine the maceral’s contribution to generation of oil and gas.The results show that the Jurassic coals in the Ordos Basin have special penological features because of the Basin’s unique depositional environment which was mainly a series of high-stand swamps in the upper fluvial system.These petrographic features are a result of the development of typical inland lakes where some sand bodies were formed by migrating rivers.After burial,the peat continued to undergo oxidizing conditions,this process generated extensive higher inertinile contents in the coals and the vitrinite components were altered to semi-vitrinite.The macroscopic petrographic types of these Jurassic coals are mainly semi-dull coal,dull coal,semilustrous and lustrous coal.The proportions of semi-dull coal and dull coal are higher in the basin margins,especially in the area near the northern margin.The numbers of semilustrous and lustrous coals increase southwards and towards the central basin.This situation indicates that different coal-forming swamp environments have major controlling effects on the coal components.Another observation is that in the Ordos" coal sequences,especially in the lower part,some sandstone beds are thick,up to 20 m with a coarse grain size.The higher fusinite content in the macerals accompanies a higher semi-vitrinite content with more complete and regular plant cell structure.The fusinite structure is clear and well preserved.After burial,the lithology of the roof and floor rocks can continue to affect the evolution of coal petrology.The sand bodies in the roof and floor exhibit good physical conditions so that pore water can maintain a long-term state of oxidation,circulation and connection to the coal.So coal components remain in an oxidation environment for a long time.Conversely,in the basin center,lacustrine facies developed and peat was rapidly covered by mudstone after burial and subsequent coal beds rapidly entered a reducing environment.As a result,abundant gelatification occurred and the vitrinite content increased.Exinite often accumulated in a specific position in the coal bed.Although the average exinite content is not high on the whole,it does significantly contribute to the total hydrocarbon generation. The exinite content has been underestimated,especially the amorphous bituminous fluid and its importance is emphasized here.The reason is that the fluid flows easily into fusinite which has strong rigidity,or flows into some fissures,where it is commonly neglected. 相似文献
12.
Boyang Wang Yong Qin Jian Shen Gang Wang Jiuqing Li 《Journal of the Geological Society of India》2018,92(1):111-119
The formation environment of the main coal seam in Shengli coal mine is analyzed, and the effect of coal ash parameters on the coal-forming environment is mainly discussed according to gray component parameters combined with other coal quality test analysis data. Results show that the hydrodynamic conditions of the main coal during coal accumulation have a general pattern of strong northeast and weak southwest, and lakeside swamp is generally in the retrograde process from south to north. The No.5 coal seam is a water entry cycle, and the No.5lower coal is a water withdrawal cycle. The No.6 thick coal seam is formed in the peat swamp environment where the water is shallow and the groundwater activity is weak. The input of terrestrial debris material was most abundant in the formation period of No.5lower coal, followed by No.5 coal, and that in No.6 coal is the least. Vertically, the peat swamp environment changed from weak reduction to weak oxidation to strong reducing environment. The ash yield was low to high to low from bottom to top. The organic sulfur is the main type of sulfur in the main coal seam. The weaker the hydrodynamic condition, the higher the organic sulfur content in the reduction environment, while lower organic sulfur content in the oxidation environment. The peat swamp water of No.5lower coal is medium alkaline, and the peat swamp water of No.5 and No. 6 coals is weakly alkaline or acidic. 相似文献
13.
14.
本文通过滇东田坝黔西土城晚二叠世煤系上段沉积相、煤层特征和煤岩煤质的综合研究,系统分析了区内煤层形成时的沉积环境.按成煤的古地理位置分为上三角洲煤相和上、下三角洲过渡带-下三角洲煤相两大类型.根据成煤的原始质料、结构构造、煤岩特征和成煤前后环境,详细划分出八种泥炭沼泽相.着重探讨3号煤层形成时的泥炭沼泽相特征及其变化. 相似文献
15.
The coal seam No. 207 was a subject of palynological and petrographic studies. According to the results of the vitrinite random reflectance measurements supplemented by moisture and calorific value determinations, the rank of this coal is matching the boundary between sub-bituminous and bituminous coals. The aim was to reconstruct the environmental conditions during the biochemical stage of seam formation, as well as the facies development throughout the seam profile. The maceral (incident and fluorescence mode) and microlithotype compositions (incident light) supplemented by palynological analyses, show that there were two main facies developments. In the authors opinion, they correspond with a phase of ombrogenous, raised bog marked by the presence of crassidurite with Densosporites variabilis and a wet-forest swamp phase represented by vitrite and clarite with more diverse spore assemblage including densospores. Other minor but distinctive sediments, a cannel layer and a reeds facies, both occurring in the lower part of the seam. Above the tonstein horizon, a dry forest type of sedimentation is recognized. 相似文献
16.
乌兰诺尔井田位于内蒙古自治区东北部,含煤地层主要为白垩系下统巴彦花组,6号煤是区内唯一可采煤层,其显微组分镜质组含量为85.2%～91.0%,惰质组含量为2.0%～13.4%,壳质组在2%以下。测试分析表明6号煤属中灰、低—中高硫、高热值褐煤,其挥发分高,化学反应性好,燃烧时速度快,反应充分,是很好的动力燃料,适用于火力发电。 相似文献
17.
对神府大柳塔矿区 2 - 2煤层系统的煤岩学研究表明 ,该煤层以镜质体和丝质体为主 ,其它组分较少 ,矿物质中以粘土类和石英为主 ,显微煤岩类型以两组分微类型为主 ,宏观煤岩类型以半暗煤和半亮煤为主 ,壳质组具有较强的荧光 ,其荧光光谱为单峰形 ,不同的壳质组分其荧光特征不同 相似文献
18.
对陕西黄陇煤田中下侏罗世延安组４号煤进行了煤岩学和孢粉学的详细定量分析，并用计算机对显微组分与孢粉类型之间的的关系作了相关分析，结果表明，煤中显微组分与孢粉类型之间在在相关关采、这种相关关系反映了显微组分的形成与成煤植物之间存在着成因上的联系，即煤中基质状和碎屑状显微组分主要由草本植物和材蕨植物形成，而其细胞结构和条带状的显微组分主要由木本裸子植物形成，，这两种类型显微组分的比值可以反映成煤植被特征。 相似文献