coal formation meaning in English

煤生成
煤系

Characteristic of china coal formation kaolinite source and current state of its processing and application
煤系高岭岩及其高白超细全动态煅烧工艺机理初析
This article has analysed the environmental impact characteristics of gangue , which from hunan coal formations , simultaneously according to the material composition characteristics of gangue to propose the reasonable comprehensive utilization way
摘要文章对湖南各煤系煤矸石的环境影响特性进行了分析，同时根据各煤系煤矸石的物质组成特点提出合理的综合利用途径。
The fast development constructs which along with the present domestic highway , the , tunnel increases day by day in highway application , carried on the tunnel construction in the coal formation stratum land sector still the not mature construction safety control measure , this article in detail sunjiazhai coal bed tunnel succeeded the construction control technology , will have certain model function to the next similar project construction
摘要随着目前国内高速公路建设的快速发展，隧道在高速公路中的应用日益增多，在煤系地层地段进行隧道施工尚无成熟的施工安全拉制措施，详细介绍孙家寨煤层隧道成功的施工控制技术，对今后类似工程的施工有一定的借鉴作用。