辽河盆地欧利坨子地区火山岩储集空间特征

辽河盆地欧利蛇子地区火山岩储集空间主要发育于角砾化粗面岩、角砾化熔岩、粗面岩及凝灰质熔岩中,玄武岩中不太发育.储集空间主要分为原生和次生两类,原生储集空间包括原生孔隙如气孔、砾间孔、晶间孔及原生裂缝如收缩缝;次生储集空间主要包括溶蚀孔和构造缝、溶蚀缝等.原生气孔和次生溶蚀孔十分发育,是主要的储集空间,约占65%～70%,收缩缝、构造缝和溶蚀缝不仅是流体运移的通道,使气孔、晶间孔等沟通,同时也提供了一部分储集空间,在Ⅳ类储集空间中,Ⅰ,Ⅱ类由于有大量的气孔,且气孔中易溶组分多,加之又有大量原生孔隙和收缩缝,因而是较好的,Ⅲ,Ⅳ类则较差.本区火山岩储集空间可划分为 4个演化阶段.第一阶段为原生储集空间的形成阶段,第二阶段为风化淋滤阶段.这二个阶段以建设性作用为主.第3阶段为浅埋藏及构造裂隙发育阶段,建设作用和破坏作用共存,但以建设作用为主.第4阶段为深埋藏阶段,则以破坏作用为主.

FEATURES OF VOLCANIC ROCK RESERVOIR SPACES IN OULITUOZI REGION,LIAOHE BASIN

Reservoir spaces of the Tertiary volcanic rocks in Oulituozi region, Liaohe Basin are generally developed in trachyte, tufflava, lava, trachydacite, brecciated trachyte, proclastic rocks, brecciated lava and can be divided into two main types. Primary pores include vesicles, inter-crystal pores, inter-breccia pores, cooling joint; the secondary porosity includes solution fissures, voids and structureal fissures. Vesicles and solution pores are the most important pore types in this area which occupy 65%～70% of the total amount of the porosity. Based on the statistics of mercury method and image plane scanning associated with the ratio curves of porosity and permeability, the reservoirs could be divided into four types. Type-Ⅰ and types-Ⅱ are favorable reservoirs. Four evolution stages of the reservoir spaces have been identified in Oulituozi region. Favorable reservoir spaces were mainly formed in the first and second stages.