珠江口盆地W油田低阻油层特殊成因机理

Special origins of low-resistivity oil layers in W oilfield,Pearl River Mouth basin

针对珠江口盆地W油田典型的正常油层c-I和低阻油层c-II,以国内外低阻油层研究成果为理论指导,对其岩石粒度、泥质与粘土矿物成分及分布、孔隙结构、束缚水饱和度、导电矿物等因素进行了对比分析,认为储层内由自生粘土矿物形成的网状导电通路以及测井仪器在砂泥岩薄互层的局限性是W油田低阻油层的特殊成因。在油田开发时应充分考虑这些因素,并制定出相应的应对措施。

Based on the domestic and foreign research results about low-resistivity oil reservoirs, a typical normal oil layer （c-I） and a low-resistivity oil layer （c-l]） in W oilfield, Pearl River Mouth basin, were compared in their rock grain size, mineral composition and distribution of shale and clay, pore structure, irreducible water saturation and conductive minerals. It was concluded that the netlike conductivity channels formed by authigenic clay minerals within a reservoir and the limitation of logging instruments for thin sand-shale interlayers may be the special origins of the low-resistivity oil layers in W oilfield. These factors should be sufficiently considered and the responding measures should be adopted during development of such oilfields.