苏里格气田苏48区盒_8—山_1段砂岩储层物性主控因素研究

MAJOR FACTORS CONTROLLING RESERVOIR QUALITY OF P_2X_8 AND P_1S_1 AT SU-48 BLOCK IN SULIGE GAS FIELD

通过岩心观察、物性分析、铸体薄片、扫描电镜、X-衍射等方法,对苏里格气田苏48区块盒8—山1段储层岩心样品进行分析测试,研究储层物性的主控因素。研究表明,苏里格气田苏48区盒8—山1段储层属低、特低孔低渗储层,其物性主要受沉积作用及成岩作用的控制。沉积作用通过控制储层的碎屑成分及沉积微相来控制其物性,心滩、边滩物性最好,分流河道次之,天然堤、分流间湾最差。压实作用是造成原生孔隙减少的主要原因,后期胶结作用产生的硅质、碳酸盐胶结物,特别是石英的次生加大,使得储层物性变差,溶蚀作用产生次生溶蚀孔,改善了储层的储集和渗流能力,微裂隙化作用使储层连通性提高,渗透性也就大大提高,储层物性得到进一步改善。

With the techniques of core observation,physical property analysis,casting section,scanning electron microscopic and XRD,the thesis makes a thorough research on the major factors controlling reservoir quality of P2x8 and P1s1 at Su-48 block in Sulige gas field.Generally,the reservoir of P2x8 and P1s1 at Su-48 block in Sulige gas field belongs to especially low porosity and low permeability reservoir,its physical property is controlled mainly by sedimentation and diagenesis.It is suggested that the depositional facies controls reservoir quality by clastic constituents and sedimentary micro-facies of the sandstones,as a result,the reservoir quality of mid-channel bar and point bar microfacies is better than braided river distributary channel,while the reservoir quality of the natural levee and the inter-distributary deposits is the worst.It is also indicated that diagenesis is another key factor modifying reservoir properties,and the mechanical compaction is the main factor which caused the loss of primary porosity for the sandstones,carbonate ce-ments,secondary enlargement of quartz are the main cementation that reduced the reservoir quality of the sandstones,while the reservoir quality was improved a lot by dissolution and micro-fracture.