页岩气储层表征评价技术进展与思考

油气勘探理论与技术的进步使非常规油气勘探开发不断取得新的突破。复杂的微-纳米级孔隙体系与特殊的流体赋存方式是页岩有别于常规储层的显著特征,并对储层表征评价内容、方法与技术手段的针对性、准确性和适用性提出了更高要求。在充分调研国内外页岩气储层表征评价技术的基础上,重点介绍了页岩气储层岩相划分与预测、矿物组分、孔隙结构、可压裂性及多尺度/手段联合方法等储层表征评价技术进展。同时,提出未来发展趋势应聚焦于以下几个方面:(1)精度与针对性的进一步提高;(2)多技术、多尺度深度融合;(3)原地/原位条件储层评价;(4)储层动态监测评价;(5)大数据油气储层评价。最后,针对中国页岩气地质条件与勘探开发现状,提出未来页岩气储层表征技术与研究发展方向应重点聚焦于以下4个方面:(1)细粒沉积特征;(2)储层时空演化特征;(3)可压裂性评价;(4)储层评价技术的融合、引进与创新。

Advancement and trends of shale gas reservoir characterization and evaluation

Breakthroughs in shale gas exploration and development are inseparable from advancement in exploration theories and technologies.The complex micro-nano scale pore systems prevalent in shale and the unique occurrence of shale gas that distinguishes itself from conventional gases require the characterization of shale gas reservoirs to be more pertinent, accurate and applicable in terms of evaluation objects, methods and techniques.On the basis of a thorough investigation on shale gas reservoir characterization and evaluation status quo around the world, this paper focuses on the advancement of such technologies as lithofacies division and prediction, mineral composition and pore structure analyses, fracability evaluation and multi-scale/technique integration.It proposes that future shale gas reservoir characterization and evaluation pivots around (1) accuracy and pertinence enhancement; (2) further integration of multiple-scale techniques; (3) in-situ condition; (4) dynamic monitoring and assessment; and (5) application of big data.In view of geological conditions, exploration and development practices of shale gas in China, the paper again proposes four aspects as the focuses of future shale gas reservoir characterization and evaluation: (1) fine-grained sedimentary characteristics; (2) temporal and spatial evolution traits; (3) fracability evaluation of reservoirs; as well as (4) integration of different technologies, introduction of foreign technologies, and most of all, innovation.