美国密歇根盆地安特里姆页岩气区带成藏特征

安特里姆页岩广泛覆盖在北美古大陆的中下泥盆统之上，其中，生物成因的天然气富集于埋深浅、欠压实、富含有机质的页岩储集层内，气体多被有机质和黏土吸附。诺伍德段和拉钦段有机质含量最高，为区带内最主要的页岩气勘探层。对密歇根盆地的安特里姆页岩气区带的烃源岩及其厚度、物性特征、矿物含量以及裂缝系统和成藏作用进行了探讨，并对区带的勘探潜力进行了评价。该区安特里姆页岩经历较深的埋深后又被抬升遭受大气淡水淋滤，在适宜的条件下生成生物气并成藏。安特里姆页岩气成藏特征的研究将会对中国页岩气勘探有所裨益。

The Reservoir Characteristics of Antrim Shale Gas Play in Michigan Basin,USA

The Antrim shale gas play that is composed of such four sections as Norwood, Paxton, Lachine and Upper Member widely covers above the Middle?Lower Devonian in North America’s ancient continent, where the biogenic gas is mainly distributed in the shallow, under?compaction and organic?rich shale reservoirs and usually absorbed by the organic matter and clay. The Norwood and Lachine sections have the highest contents of organic matter as major zones for shale gas exploration in this area. This paper analyzes the source rock, thickness, physical property, mineral content, fracture system and its reservoir?forming role of this play, and then evaluates its explorative potentials.It is concluded that it is easy to generate biogas if the shale gas is deposited in deeper depth, then uplifted and suffered air and fresh water leaching, followed by forming the gas accumulation under suitable geological conditions. This study will be helpful for China’s shale gas exploration in the future