中国石墨矿成矿特征及成矿区带划分

石墨广泛应用于冶金、机械、航空、航天、电子信息、新能源汽车等领域,已成为高新技术领域中的重要原料。近年来陆续发现了内蒙古查汗木胡魯、四川南江等大型区域变质型石墨矿,尤其在新疆黄羊山地区发现了特大型岩浆岩型晶质石墨矿,为石墨成矿规律研究提供了新的方向。本文在广泛收集和研究以往石墨成果的基础上,结合野外实地调研和最新石墨勘查成果,系统总结了石墨时空分布规律、成矿地质作用,划分了石墨成矿区带。中国石墨矿矿床类型以区域变质型为主,成矿期以前寒武纪为主,其形成的石墨鳞片大,结晶程度高,经济意义大;岩浆岩型晶质石墨矿赋矿围岩为海西期碱性花岗岩,成矿时代与岩浆侵入时代一致;接触变质型石墨矿赋矿层位较集中在二叠—侏罗纪,其成矿作用与燕山期—海西期中酸性岩浆活动密切相关。稳定隆起区的大型复式褶皱构造翼部及转折端是石墨成矿有利的构造单元。初步划分了石墨成矿区带21个,提出佳木斯—兴凯(地块)石墨成矿带、华北陆块北缘中段石墨成矿带、胶北隆起石墨成矿带、准噶尔地块石墨成矿带、华北陆块南缘—秦岭等石墨成矿带较为重要。本次石墨成矿规律总结及成矿区带初步划分对指导石墨找矿勘查部署具有一定意义。

Metallogenic characteristics and metallogenic zoning of graphite deposits in China

Graphite is widely used in such fields as metallurgy, machinery, aviation, aerospace, electronic information, and new energy vehicles, and has become an important raw material in the high technology. In recent years, Chahanmuhulu deposit in Inner Mongolia, Nanjiang deposit in Sichuan and and some other large-sized metamorphic graphite ore deposits have been found, especially the discovery of the Huangyangshan magmatic type crystalline graphite deposit in Xinjing has indicated a new direction for the study of the metallogenic regularity of graphite deposits. Based on the extensive collection and study of the past graphite achievements, combined with field research and latest graphite exploration results, the authors systematically summed up temporal and spatial distribution regularity and metallogenic factors of graphite deposits, and divided the metallogenic zone of graphite deposits. In China, the graphite ore deposits are dominated by regional metamorphic type, and the main metallogenic period is Precambrian; the deposits formed in this period have large graphite scale, high crystallinity and great economic significance. The host rock of magmatic rock type graphite deposit is Hercynian alkaline granite, whose metallogenic age is the same as the age of magma invasion; the contact metamorphic graphite ore deposits are mainly concentrated in the Permian Jurassic period, and their mineralization was closely related to the intermediate acid magmatism of the Hercynian period. The large fold structure and the transitional end of the large fold structure in the stable uplift area are favorable structural units for the formation of graphite. The authors preliminarily divided the country into 21 graphite metallogenic zone, and pointed out that Jiamusi-Xingkai (massif) graphite metallogenic belt, middle northern margin of North China block graphite metallogenic belt, Jiabei uplift metallogenic belt, Junggar massif metallogenic belt, southern margin of the North China continental block, Qinling and some other graphite metallogenic belts are especially important. The summary of the metallogenic regularity of the graphite deposits and the preliminary division of metallogenic belts are of significance for guiding the prospecting and exploration of graphite deposits.