陆相致密油微观成藏机理研究进展

Progress of Research on Continental Tight Oil Accumulation Mechanism

通过国内外文献调研,首先分析了致密油术语的应用情况,将广义和侠义之分的产生原因,总结为储层描述、技术开发、宏观统计和成藏成因四种;然后研究致密油的微观成藏机理发展的推动因素,表明致密油储层微观机理的发展得益于水平井分段压采技术、大量致密油资源的特征总结和大面积连续型油气聚集理论的发展。最后总结当前陆相致密油储层微观成藏机理的三方面进展:(1)致密油储层成藏时,油气能否进入储集层的孔隙下限研究。表述的物性孔隙下限有两种不同的定义。不同实验手段得出的结果有所差异;(2)致密油储层的烃源岩特征,生、排烃产生的压力研究。已证明烃源岩生、排烃提供致密油位移的动力,成熟时的排酸现象影响着致密油储层的物性;(3)致密油成藏时,流体在微-纳米孔喉中运移规律研究。在缺乏动力的条件下,流动方式以渗流、滞留为主,受到毛细管阻力、黏滞力和分子作用力,需要"启动压力"才能发生位移。

Through the domestic and foreign literature research gy,divides the causes of the two definitions into four types： , we analyzed the application of the tight oilterminolo- reservoir description, technology development, macro statistics and hydrocarbon formation;Then, the development process driving factors of tight oil microscopic reservoiring mechanism were studied, which indicated that the development of segmental fracturing technology for horizontal wells, characteristics of a large number of tight oil resources and large - scale continuous oil - gas agglomeration theory. finally, the three aspects of microscopic reservoiring mechanism of terrestrial tight oil reservoir were summarized ： ①in the tight oil reservoir accumulation process, oil and gas could enter the reservoir porosity threshold of the study, there are two different definitions to expression of the porosity threshold and different experimental means the difference between the results; ②the tight oil reservoir of hydrocarbon source rocks characteristics, the hydrocarbon generation. The hydrocarbon generation of source rocks provide the motivation of tight oil displacement, and source rocks of the acidic fluid affects the physical properties of tight oil reservoir; ③in the tight oil reservoir accumulation process,the movement law in the micro - the pore throat. Under the condition of lack of motivation,flow mode is seepage and retention. Due to the capillary resistance, viscous force and the molecular force, the start - up pressure is needed.