中国北方不同成煤时代煤中金属矿点(床)分布及资源前景

在特定环境下,煤中能够富集锗、镓、锂、稀土等金属元素。我国北方煤炭资源丰富,已发现大量的煤-金属矿点(床),并且这些矿点(床)的分布展现出一定的时空特征:石炭-二叠纪煤中金属主要以镓、锂富集矿点为主,主要分布在华北赋煤区北部煤田及山西平朔、晋城等矿区;早-中侏罗世煤,以镓富集为主,主要集中在新疆准东、吐哈盆地,青海木里等煤田,二连盆地早侏罗世煤发现煤-稀土异常,是很好的找矿线索;早白垩世煤主要以二连盆地、海拉尔盆地煤中锗矿点为主。我国北方聚煤期时间跨度大,聚煤环境多样,含煤盆地类型多样,聚煤期和成煤后北方频繁剧烈的大地构造演化过程、多样的煤岩类型,能为煤中不同微量元素的富集提供物质来源、迁移条件与通道和沉积聚集条件,具有良好的煤中金属资源前景。建议进一步加强煤中,尤其是煤矸石、粉煤灰中金属矿点(床)资源的调查研究工作,为煤中金属资源赋存与预测提供参考,并加强金属的提取利用技术研究,同时通过制定资源保护政策,加强对煤中金属资源的保护。

Distribution and resource prospect of metal ore spots(deposits) in coal of different coal-forming ages in northern China

In some cases, metals such as germanium, gallium, lithium and rare earth elements can be enriched in coal, which is an important potential source of these metals. There are abundant coal resources in northern China, and a large number of coal-metal ore spots(deposits) have been found, and the distribution of these ore spots(deposits) shows certain temporal and spatial characteristics:Metals in Permo-Carboniferous coal occur mainly as gallium and lithium-enriched ore spots, mainly are distributed in the northern coalfields of North China coal bearing regions and mining areas such as Pingshuo and Jincheng in Shanxi Province; the metal enrichment in Early-Middle Jurassic coal is mainly concentrated in Zhundong, Tuha in Xinjiang Autonomous Region, Muli coalfield in Qinghai Province, and is mainly gallium-enriched in coal, coal-rare earth elements anomaly has been found in the Early Jurassic coal in Erlian basin, which is a good prospecting clue; the Early Cretaceous coal mainly contains germanium in Erlian basin and Hailar basin. The time span of coal-accumulating period in north China is long, the coal-accumulating environments are diverse, the types of coal-bearing basins are diverse, the frequent and violent tectonic evolution process in north China after coal-accumulating period and coal formation, and the diverse types of coal rocks could provide material source, migration condition, channel and sedimentary accumulation condition for the enrichment of different trace elements in coal, which has a good prospect of metal resources in coal. It is suggested to further enhance the investigation and research work of key metal ore spots(deposits) resources in coal, especially in gangue and fly ash, so as to provide reference for the occurrence and prediction of key metal resources in coal, strengthen the extraction and utilization technology of key metals, and the protection of key metal resources in coal by formulating resource protection policies.