孤岛油田馆陶组河流相储层隔夹层成因研究

Interlayer characterization of fluvial reservoir in Guantao Formation of Gudao Oilfield

隔夹层是形成陆相储层流体流动非均质的主要原因之一,是控制厚油层复杂水淹形式的主要地质因素。研究结果表明,河流相储层隔夹层的成因类型可分为沉积作用形成的隔夹层及成岩作用形成的隔夹层两大类,隔夹层在注采井组范围内的分布状况对油水运动和最终采收率有很大的影响。隔夹层和其他因素共同作用可使厚油层出现多段水淹、强水淹段与未动用段共存的状态。隔夹层的存在有利于正韵律和块状韵律油层扩大纵向波及体积和驱油效率,不利于提高反韵律油层的注水波及效率。

The interlayer is the main cause to form the heterogeneity of fluid flow in the continental reservoir and is also the major geological factor for controlling complex water-flooded modality of thick layer. The interlayer of fluvial reservoir can be divided into two types generated by sedimentary origin and diagenesis. The distribution of interlayer in the injected reservoir has some influence on the distribution and migration of oil and water and controls the ultimate recovery of reservoir. Combined with other factors, the interlayer can result in coexistence of watered, high watered and un-watered areas in thick layers. The existence of interlayer is very favorable to dilate vertical swept volume and efficiency of water drive for the positive rhythm and block rhythm reservoirs, but it is unfavorable to enhance the sweep efficiency in the reverse rhythm reservoir.