- coal field fire extinguishing
- The ash may be from the north east of theDatong coal field.
- Yangquan City, the northeast corner of the Qinshui coal field.
- Hegang coal field, of the type of a (inland) faulted basin far from the sea, was formed in the early Neo-Jurassic age about 140 million years ago.
- The geology survey of Hegang coal field are introduced and some obvious characters of workable seam are compared.
- The exploration result basically accords with the geologic profile of coal field bores and bore validating of goaf.