苏里格庙地区凝灰质溶蚀作用及其对煤成气储层的影响  

Dissolution of Tuff Filling and Its Effects on the Porosity of the Coal-formed Gas Reservoir in the Suligemiao Area of the Ordos Basin

作　　者：张凡芹[1] 王伟锋[1] 王建伟[2] 孙粉锦[3] 刘锐娥[3] 

机构地区：[1]中国石油大学地球资源与信息学院,山东东营257061 [2]胜利油田现河采油厂地质所,山东东营257062 [3]中国石油勘探开发研究院廊坊分院,河北廊坊065007

出　　处：《吉林大学学报（地球科学版）》2006年第3期365-369,共5页Journal of Jilin University：Earth Science Edition

基　　金：国家重点基础研究发展规划项目(G19990433)

摘　　要：苏里格庙地区二叠系煤成气储层非均质性明显,次生孔隙发育,砂岩中含有大量不稳定凝灰质填隙物。溶蚀模拟实验表明,在酸性水环境中,凝灰质填隙物发生明显溶蚀,并且酸性介质浓度越高溶蚀作用越强烈。在有残余粒间孔隙或裂缝沟通的较开放环境里凝灰质填隙物溶蚀作用强烈;而在较封闭的环境中,溶蚀作用不能充分进行,凝灰质填隙物保存较好。凝灰质填隙物溶蚀产生的次生孔隙,改善了煤成气储层的储集性能;但由于异地胶结作用,又在一定程度上损害了煤成气储层的整体连通性,这是鄂尔多斯盆地二叠系煤成气储层强非均质性和低渗透性的根本原因。The Permian coal-formed gas reservoir in the Suligemiao area is characterized by heterogeneity, secondary pore and abundant non-stable tuff fillings. The simulative experiment shows that tuff fillings is obviously dissolved under the acid conditions. And with higher acid concentration, the dissolving ability of tuff fillings is intensive. However, the simulative experiment reflects only the dissolution of tuff fillings under open water environment. But under enclosed burial water environment, because the dissolvable products can not be discharged in time and acid becomes weaker, the dissolution of tuff fillings can not be processed fully and tuff fillings is preserved well. The secondary pores induced by dissolution of tuff fillings may improve the storage capacity of reservoir, but they also destroy the intercon- nection of reservoir to some extent. This is just the reason why the Permian coal-formed gas reservoir under study is heterogeneous and is of very low permeability.

关 键 词：苏里格庙地区 煤成气储层 凝灰质填隙物 溶蚀作用 次生孔隙 

分 类 号：P618.13[天文地球—矿床学]