摘要
NATURAL gases usually refer to the inflammable gases dominated by methane from the angle of research on energy gases. Three genetic types of natural gases can be recognized according to the process of methane generation: (ⅰ) biogenic (bacterial) gas, mainly the gas formed by the decomposition of organic matter in sediments under the action of anaerobic bacteria; (ⅱ) thermogenic gas, mainly the gas formed by the degradation of organic matter in sediments under the action of certain temperature and pressure; (ⅲ) abiogenic gas, mainly the
