摘要
鲁西南地区煤炭资源丰富,煤质较好,煤变质作用主要属于区域变质,部分地区接触变质作用明显。通过对煤田煤质特征的研究,探讨了不同时期主导煤变质作用的类型及其对煤变质程度的影响。结果表明,三叠纪以前研究区在构造作用下沉降,煤变质主要受深成变质作用影响且各地差别不大,至三叠纪末期煤的变质程度已经接近长焰煤;三叠纪以后南北煤田R值出现显著差异,中北部各煤田煤变质仍然由深成作用主导,而南部济宁、巨野、滕南等煤田在侵入体的作用下,区域岩浆热变质作用开始主导煤变质,接触变质作用发生在巨野、滕南等有岩浆侵入或接近煤层的局部地区;在东部煤田含有大量无烟煤和天然焦,肥煤所占比例明显比中西部大,这是由于郯庐断裂剧烈的水平地层错动,煤系受到动力变质作用影响。
Coal resources in the southwestern Shandong area are abundant. Coal metamorphism mainly belongs to regional metamorphism, but locally obvious contact metamorphism. After studies on coalfield coal quality, discussed the leading coal metamorphism types and their impact on coal metamorphism degree during different periods in southwestern Shandong. The study area had been subsided before Triassic under tectonism, coal metamorphism mainly impacted by hypozonal metamorphism and difference between areas is not large, coal rank was already close to long flame coal to the end of Triassic. After Triassic the R values of coalfields in the south and north present obvious difference, coalfields metamorphism in middle and northern parts were still leading by hypozonal metamorphism, while in southern coalfields such as Jining, Juye and Tengnan coalfields had been impacted by magmatic intrusion, thus the magmatic thermometamorphism was the leading coal metamorphism, the contact metamorphism had happened in local parts of Juye,Tengnan coalfields with magmatic intrusion into or near coal seams. In eastern part coalfields have abundant anthracite and natural coke, the proportion of fat coal is obviously larger than in middle and western parts coalfields, thus because of impact from severe horizontal strata dislocation of the Tancheng-Lujiang fault caused dynamic metamorphism in coal measures.
出处
《中国煤炭地质》
2015年第10期6-9,共4页
Coal Geology of China
基金
国家自然科学基金"环渤海湾地区晚古生代海侵事件沉积等时性及时限尺度的研究"(41202070)
山东省优秀中青年科学家科研奖励基金计划项目"大型陆表海盆地海侵事件沉积及事件古地理特征--以华北板块晚古生代盆地为例"(BS2011SF017)联合资助
关键词
鲁西南
煤变质
煤类分布
southwestern Shandong
coal metamorphism
coal ranks distribution
