泥晶碳酸盐岩的超微结构分析及其成岩作用

Analysis of Ultrastructure and Diagenesis of Micritic Carbonate Rocks

以超微技术手段研究细粒碳酸盐岩的结构,可探讨其多种原因,成岩次生变化和孔隙类型,并对其储集性能进行评价。通过SEM扫描分析已证明化学成因的碳酸盐岩具有自形程度不同的等粒和不等粒结构,晶间孔发育;生物成因的岩石中可见残留的生物屑和藻迹或清晰的孢子囊、藻管和藻团,岩石以粒内孔和粒间孔为主;机械成因的泥晶碳酸盐岩则具泥屑结构。细粒碳酸盐岩中粘土矿物的鉴定有助于判断沉积和成岩环境。 综合研究我国南、北方不同时代细粒岩石,可查明泥晶岩石的原生和次生孔隙类型及演化历史。

Studying fine-grained carbonate rocks by ultra-technique can inquire into its vari-ous origin, secondary change in diagenesis and type of pores and evaluate its reservior properties. Analysis by SEM proved that chemogenic carbonate rocks have the equigran-ular and inequigranular texture with various euhedral degree, and the inter-crystaline pores are abundant. The remains of fossil fragment, algae trace or distint sporangia, algae tube, algae ball can be seen under SEM system in biogenic carbonote rocks. Pores in this kind of rocks are mainly inter- particle and intra-particle. The micritic carbonate rocks of mechanical origin have mud-debris structure. Identification of clay minerals in fine-grained carbonote rocks is useful, in deterimning the sedimentary and diagenetic environment.By synthetical study on fine-grained carbonate rocks of various ages in southern and northern China, we can find out the primary and secondary types of pores and its developmental history which is of practical significance in calculate the potential reservoir beds.