Abstract: This paper puts forward a method to distinguish reservoir types in carbonate formation based on the electrical conduction efficiency.Relationships between the rock electrical conduction efficiency and the cave size,fracture width,and throat diameter are presented.These relationships show that, 1) In the condition that only fractures and caves exit,the electrical conduction efficiency of the rock increases rapidly along with the increasing of fracture width, especially when caves are small; 2)When only throats and caves exist,the electrical conduction efficiency of the rock increases along with the increasing of throat diameter; 3) The electrical conduction efficiency of the rock decreases along with the increasing of cave size.Thus,the rocks electrical conduction efficiency is high when fractures exit in rocks,while low when caves exits. Electrical conduction efficiency can be used to distinguish types of carbonate reservoir.This method has been applied in the Ordovician carbonate reservoir located in the middle of the Tarim Basin of China with good results.

Key words: well logging, well logging interpretation, carbonate rock, reservoir type, electrical conduction efficiency

摘要： 提出由岩石导电效率区分碳酸盐岩储层类型的原理和方法.推导了岩石导电效率与岩石中孔洞大小、裂缝宽度以及导电效率与孔洞大小、喉道直径之间的关系式.关系式表明:1若岩石中仅存在裂缝和孔洞,随裂缝宽度的增大,导电效率很快增大,尤其是当孔洞较小时;2若岩石中仅存在喉道和孔洞,随喉道直径的增大,导电效率缓慢增大;3随孔洞尺寸的增大,岩石导电效率降低.因此,裂缝型储层的导电效率远高于孔洞型储层的导电效率,用岩石导电效率这一参数,可以区分碳酸盐岩储层的储集空间类型.通过在塔里木盆地奥陶系碳酸盐岩地层中的应用表明,该方法具有较好的应用效果.

关键词: 测井, 测井解释, 碳酸盐岩, 储层类型, 导电效率