世界巨型气田分布特征及其启示

Distribution characteristics of giant gas fields in the world and its enlightenment

截至2018年底,全球共发现巨型气田(原始可采储量大于1×10^12m^3)28个,分布于12个国家的12个盆地中,总体分布极不均衡.28个气田中有21个纯气田、4个气顶气田、3个凝析气田;除俄罗斯麦德维热气田为致密砂岩气外,其余皆为常规天然气.巨型气田的储集层和烃源岩大多位于古生界和中生界,从巨型气田的储量和数量来说,志留系和白垩系是全球巨型气田的主要烃源岩,白垩系和二叠系是全球巨型气田的主要储集层.巨型气田储集层岩性以砂岩和灰岩为主,烃源岩岩性以泥页岩为主.参照全球巨型气田富集规律,结合我国实际地质情况,初步建议我国巨型、大型气田的寻找应加强大区域全盆地的综合研究,加强煤成气、深部天然气的勘探.

By the end of 2018,28 giant gas fields(recoverable reserves more than 1 trillion cubic meters)have been found in the world,distributed in 12 basins of 12 countries,and the distribution of giant gas fields is extremely uneven.Among them,there are 21 pure gas fields,4 gas cap fields,3 condensate gas fields.All the natural gas fileds are conventional gas fields except that the Medvezhye gas field is a tight gas field.The reservoir and source rock distribution of the giant gas fields are mostly located in the Paleozoic and Mesozoic.In terms of quantity and reserves of giant gas fields,the Silurian and the Cretaceous are the main source rocks and the Cretaceous and the Permian are the main reservoirs of the global giant gas fields.The lithology of the reservoir are dominated by sandstone and limestone,and the lithology of the source rock is dominated by shale.The exploration for giant and large gas fields in China should strengthen the comprehensive research of the whole basin in the large area,and the exploration of coal-formed gas and deep gas.