中国非常规天然气勘探雏议

非构造控藏是包括煤层气、页岩气、根缘气、水溶气、水合物等类型在内的几乎所有非常规机理天然气聚集的共同特征，特殊的赋存状态和富集特点使它们在盆地空间内构成了依次渐变的分布序列。其中，根缘气、煤层气和页岩气的勘探开发价值较高，也是目前非常规天然气勘探中的主要类型。致密储层中的根缘气是中国非常规天然气勘探的主要类型，主要在中西部地区具有良好的发育地质条件，砂岩底部含气是其识别和勘探的主要特点。煤层气是吸附状态天然气富集的代表类型，对于大中小型盆地的油气勘探均具有重要意义。页岩气具有煤层气和根缘气在成藏意义上的双重特征，吸附机理的存在提高了页岩气资源量并延伸了勘探领域，页岩气可能是中国南方地区油气进一步勘探的重要突破口。中国非常规天然气具有广阔的勘探前景，加强理论、技术研究及交流，将能够更好地促进非常规天然气的勘探与发展。

REMARKS ON UNCONVENTIONAL GAS EXPLORATION IN CHINA

Nonstructural mechanism is the common feature of unconventional gas accumulation such as coal-bed methane, gas shale, source-contacting gas, water-dissolved gas, gas hydrate and so on. Special mode of occurrence and enrichment characteristics make them accumulated and distributed sequentially to constitute gas spectrums in different basins. As the main targets for unconventional gas exploration, source-contacting gas, coal-bed methane and gas shale have preferable value for exploration and development. Source-contacting gas is one of the most favorable types for unconventional gas exploration in China, especially the Middle and Western basins, of which the occurring from the bottom of tight sand is the general characteristics for identification and exploration. Coal-bed methane is the representative type of enrichment of absorbed gas, which is significant for hydrocarbon exploration in medium and small sized basins in China. Gas accumulation mechanism in shales has not only the characteristics of coal-bed methane but also that of source-contacting gas. Absorption increases the resource quantity of gas in shales and expands the fields for gas exploration. Gas in shales may be the important breakthrough field for further hydrocarbon exploration in Southern China Area. Since unconventional gas has an extensive exploration prospect in China, theory studies, technology improvement, and external academic communion are necessary, which will improve greatly the development of unconventional gas in China.