摘要
热液白云岩储层的岩石特征与密西西比 Pb-Zn 硫化矿床的白云岩容矿层相似,以广泛发育的基质交代型和孔-缝充填的鞍形白云石为标型特征,同时含有少量其他热液矿物如闪锌矿、方铅矿、石英、黄铁矿、重晶石以及萤石等,另外还经常可见被鞍形白云石充填的因剪切应力形成的微裂缝、斑马纹构造和白云岩角砾。由于热液流体对原碳酸盐岩(主要是灰岩)的差异性溶蚀,往往保留了未被充满的孔洞、缝,为油气的充注提供了空间。输导热液流体的断裂系统通常为张性或扭张性断裂系统,白云岩化作用主要发生在断裂系统的上盘,并沿着孔渗性相对较好的原岩侧向推进。借助于高分辨率地震属性分析和成像技术,可以对热液白云岩储层进行表征和预测,从而为油气勘探决策提供依据。
Sharing similar lithologic characteristics with dolomite seam hosting MVT Pb-Zn sulfide ores, hydro- thermal dolomite reservoirs contains mainly massive-matrix-replacement dolomites and void- or fracture-filling saddle dolomite dotted with small amount of other hydrothermal ores, such as sphalerite, galena, quartz, pyrite, barite, and fluorite. Saddle dolomite-filling microfractures and zebra textures formed by shear stress and dolomite breccias are also common in these reservoirs. Unfilled vugs, fractures, and pores from differential dissolution of the original carbonates （mainly limestone）provide the necessary spaces for later hydrocarbon charges. The hydrothermal fluids preferentially flow upwards along the extensional and transtensional fault systems, where dolomiti- zation preferentially occurs on the hanging walls and extends laterally in the course of fault propagation. The bydrothermal dolomite reservoir can be well characterized and predicted through high-resolution seismic attribute analysis and imaging.
出处
《石油与天然气地质》
EI
CAS
CSCD
北大核心
2008年第5期614-622,共9页
Oil & Gas Geology
基金
国家自然科学基金资助项目(40372062)
关键词
伸展断层
扭张断层
构造控制
热液白云岩
白云岩储层
extensional fault
transtensional fault
structural control
hydrothermal dolomite
dolomite reservoir
作者简介
陈代钊（1963-），研究员，碳酸盐沉积学和地球化学。
