兴城气田火山岩储层储集特征研究

 兴城气田火山岩储层岩性复杂,储集性能迥异。为了比较不同火山岩储集特征，寻找优质储集体，从火山岩储层孔隙成因及演化入手，应用岩心分析测试及镜下鉴定手段，对岩石组构、成岩作用以及储层物性对构造作用的响应3个岩石储集性能的影响因素进行研究，分析对比了兴城气田各类火山岩进行储集性能。分析认为，火山岩储层物性主要受成岩作用的类型及发育程度以及构造作用控制，而岩石组构决定了火山岩所发生的成岩作用类型，也决定了构造作用对储层的改造程度，有利的岩石组构是是形成优质储集体的前提；即岩石组构、成岩作用、构造作用三者影响储集空间的演化，岩石组构是火山岩储层储集性能的主要控制因素；研究区内有利岩石组构储集岩性有火山角砾岩、气孔流纹岩、角砾熔岩；其中，角砾熔岩的岩石组构利于原生孔隙的保存与次生孔隙的发育，储集性能最优，火山角砾岩与流纹岩次之，火山集块岩、凝灰岩、致密流纹岩、低孔流纹岩不易形成有效储集体。

Volcanic Reservoir Characteristics in Xingcheng Gas Field

The reservoir in Xingcheng gas field has a complex lithology. In order to study the diversity of the capability of reservoirs and to find a most favorable reservoir, this paper analyzes the pore genesis and evolution, the petrosal structural fabric, and the physical properties related with tectonic disturbance, as the controlling factors of the reservoir storage. The results show that reservoir physical properties influence the diagenesis type and development, and tectonic disturbance. The petrosal structural fabric controls diagenesis and the physical properties related with tectonic disturbance. Advantageous petrosal structural fabric is a very important prerequisite for a favorable reservoir formation and is the main controlling factor for volcanic reservoir properties. In the studied area, the favorable reservoir rocks comprise volcanic rubble, rubble lava, and porous rhyolite, where rubble lava is the most important component, volcanic rubble and porous rhyolite take the second place, volcanic agglomerate, tuff, competent rhyolite, and low-porosity rhyolite can hardly be the effective reservoir rocks.