渤海湾盆地歧口凹陷中新生代火成岩储层特征

Characteristics of the Mesozoic-Cenozoic igneous reservoirs in the Qikou depression of Bohai Bay Basin

在岩心观察基础上,根据大量常规薄片与铸体薄片的鉴定与统计,通过孔隙度与渗透率测定等手段,对歧口凹陷中新生代火成岩储层的岩石类型、储集空间类型、物性特征等进行了详细研究,同时对火成岩储层发育的主控因素进行了阐述和分析。结果表明:歧口凹陷中新生代火成岩可分为6大类20余种火成岩岩石类型;其中,以安山岩和玄武岩类物性最好,其次为辉绿岩和凝灰岩,英安岩最差;火成岩储层的形成与储集性能的改善主要与构造作用、风化淋滤作用、溶蚀作用、蚀变作用有关。

The Mesozoic-Cenozoic igneous reservoirs in the Qikou depression of Bohai Bay Basin are studied for rock type,reservoir space and physical property based on identification and statistics of core observation,conventional thin section and cast thin section,as well as porosity and permeability measurements. The major control factors of igneous reservoir development are demonstrated and analyzed. The results show that the Mesozoic-Cenozoic igneous rocks in the Qikou depression can be classified into more than 20 types in six categories. The best physical property is found in andesite and basalt,then in diabase and tuff,and the poorest is in dacite. The formation and quality improvement of igneous reservoirs are closely related to tectonism,weathering,leaching,dissolution and alteration.