松辽盆地长岭断陷营城组火山岩储集空间特征及演化

通过对长岭断陷营城组火山岩岩心、铸体薄片的详细观察和物性资料的统计分析认为,该区储层岩石类型多样,主要有流纹岩、流纹质晶屑凝灰岩和原地自碎角砾化熔岩等,不同岩石类型其储集空间发育特征不同,但主要由原生气孔、次生溶孔和裂缝组合构成储集空间。储集空间演化过程可分为三个阶段:原生储集空间形成阶段、表生淋滤作用阶段和埋藏成岩作用阶段,在以上演化过程中,储集性能受岩性岩相、构造运动和风化淋滤溶蚀作用的共同影响,在受深大断裂控制的火山机构近火山口相带、古构造高部位的溶蚀岩相带,裂缝及后期溶蚀孔隙发育,是优质储层分布区。

Reservoir space characteristics and evolution of the volcanic rocks in Yingcheng Formation of Changling fault depression, Songliao Basin

By careful observation on volcanic drilling cores, casting thin sections and statistical analysis of petrophysical properties, it can be suggested that the igneous rock reservoir of the Yingcheng Formation in the Changling fault depression is composed of different rock types, mainly ryholite, ryholitic crystal tuff and in-situ autoclastic brecciation lava. There are different reservoir spaces in various lithological igneous rocks, but they are mainly composed of primary stomata, secondary solution pores and fractures. Their evolution processes can be divided into three stages: The primary reservoir space, exogenic leaching process and burial diagenesis. During the process, the reservoir qualities are affected by lithology and lithofacies, tectonics and dissolutions due to weathering leaching. Therefore, the near-crater facies of volcanic apparatus, which are distributed along the deep faults and dissolution zones on the high position of paleo-structures, are the favorable places for the high-quality volcanic reservoirs in the Changling fault depression.