中国含油气盆地深层勘探的主要进展与科学问题

Main advances and key issues for deep-seated exploration in petroliferous basins in China

中国沉积盆地深层的油气勘探实践不断取得进步,提出了与之密切相关的油气地质基础科学问题,凝练与分析这些问题将为深化我国沉积盆地深层地质研究与油气勘探提供引领。近年来,我国在深层海相碳酸盐岩、砂砾岩、火山岩、变质岩与页岩气等勘探领域中发现了一系列大型油气田,油气勘探发现深度推进到7 000～8 500m,勘探前景良好。但由于沉积盆地深层经历了长期构造演化,温、压场与应力场变化大,地质结构多变,油气成藏过程复杂,深层油气勘探面临着一系列关键地质问题,主要包括:中国大陆的形成演化及其构造-古地理,中国小克拉通地块之上海相盆地的原型及演化,中国沉积盆地的多期改造过程与叠加地质结构,沉积盆地的成因机制与动力学演化,深层烃源岩发育、成烃机制及其演化,深层储集体的形成机制与分布,深层油气成藏机制,多期叠加、改造背景下油气聚集与分布规律,深层页岩气赋存机制与分布规律,过程导向的沉积盆地4D动态模拟。我国沉积盆地深层的油气地质基础研究与实际应用需求相比有较大差距,需要立足于中国大陆实际,在盆地的形成演化过程与油气成藏动力学等方面进行深入探索,期望在活动论构造-古地理、三维构造复原、流体-岩石相互作用与四维动态模拟方面取得实质性进展。

Oil and gas exploration of deep-seated plays in sedimentary basins in China has gained a series of progresses,raising key petrogeological questions in related fields.Insights from these questions will deepen our understanding of deep basin geology and thus guide oil and gas exploration in China.In recent years, giant oil and gas fields are discovered in China in the exploration areas of marine carbonates,sandyconglomerates,volcanic and metamorphic rocks,and shale gas.The exploration targets have reached 7000 - 8500 m in burial depth,with good prospects.However,as the deep-seated basins had experienced long period of tectonic evolution,large variations in temperature,pressure and tectonic stress field,different geological architecture and frameworks,and complex oil and gas pool-formation processes,its exploration has been challenging.The key geological questions are:formation and evolution of China's continents and its tectonopaleogeography;prototype basins and their evolution in the small-scale cratonic continental blocks in China;multi-stage modification and superimposed geological architecture of sedimentary basins in China;mechanism for and dynamic evolution of sedimentary basins;occurrence of deep-lying source rocks and mechanism for hydrocarbon generation and evolution;formation mechanism for and distribution of deepseated reservoirs;pool-formation processes in deep basins;oil and gas accumulation and distribution under multi-stage superimposition and modification;mechanism for deep-seated shale gas occurrence;and processoriented 4-D dynamic modeling of sedimentary basins.Today,basic research on the geology of deep-seated oil and gas is still lagging far behind practical requirements.Therefore,in-depth investigation of basin formation and evolution and geodynamics of oil and gas pool-formation,based on China's continental reality,is much needed.We also look forward to key advances in mobile tectonopaleogeography,3-D structural restoration,fluid-rock interaction,and 4-D dynamic modeling.