苏丹穆格莱德盆地古近系储层微观特征分析

从储层的岩性、成岩作用、孔隙类型及影响孔隙结构的因素等方面，对苏丹穆格莱德盆地古近系储层的孔隙结构特征进行了分析，揭示了该储层的微观特征及其对开发的影响。研究结果表明，该储层以岩屑石英砂岩及长石石英砂岩为主，结构成熟度低。成岩作用类型多样，成岩阶段进入早成岩B亚期。孔隙类型以原生粒间孔为主，有少量溶蚀孔。孔隙结构以粗孔粗喉型为主，少量中孔中喉型。压实作用、岩石粒度及泥质含量是影响研究区储层孔隙结构的主要因素。同时还指出，储层岩石粒度、泥质含量受沉积相控制，须加强沉积微相的研究；粘土矿物以高岭石为主，具有速敏性，在油田注水开发时为防止伤害孔隙结构和破坏储层，应采取适当的注水速度。

Microcosmic characteristic analysis of Paleogene reservoir in Melut Basin of Sudan

The pore structure character of reservoir of Paleogene in Melut Basin of Sudan was analyzed by studying the effect of lithology, diagenesis, pore types and clay minerals on pore structure. This reveals micro-features of the reservoir and its effects on development result. Reservoir lithology is mainly lithic quartz arenite and feldspathic quartz arenite, which has low textural maturity. It has various kinds of diagenesis types and its diagenesis stage belongs to B stage of early diagenesis. Original inter-granular pore is major pore type along with a few secondary pores among types of pore in the reservoir. Pore structure is mainly large pore with large throat, a few being medium pore with medium throat. Diagenesis, granularity and shale content have main effect on pore structure, Sedimentary micro-facies controlling granularity and shale content should be studied. Among clay minerals, the content of kaolinite is the highest and is of destructed role to pore structure because of fast water injection. To prevent damaging pore structure in watered exploiting, the flowing velocity of iniected fluid should be suitable.