地下煤火在人类出现前就已存在,或瓦斯在高温中自燃,或煤层被雷电触燃,或森林草原烈火向煤矿蔓延。到今天,由于人类的失火、纵火,地下煤火越烧越旺,火点越来越多。自燃加人为,使每年有数以10亿吨计的煤炭白白焚毁。全球地下煤火约有1万点以上,有的已经延烧几百年、几千年。美国16个州至少有260个煤井在燃烧,既有被遗弃的废井,也有未采的煤层和露天 Underground coal fire existed before the advent of humankind, or spontaneous combustion of gas at high temperatures, or the seam was ignited by thunder and lightning, or forest fires spread to coal mines. Today, due to human misfire, arson, underground fire burned more prosperous, fire more and more. Combustion and man-made, so that each year hundreds of tons of coal burned in vain. There are over 10,000 underground coal fires in the world, and some have been burning for hundreds or thousands of years. At least 260 coal mines are burning in 16 U.S. states, including abandoned abandoned wells, unsuspended coal seams and open-air