In order to study the dominant seepage channel of the third member of Weizhou formation (Ew₃) in Weizhou 12-X oilfield, Weixinan Sag, Beibu Gulf Basin, and tap the potential of remaining oil. The distribution and causes of the anomalously high permeability zones in Weizhou Formation were studied by using conventional core physical property analysis, scanning electron microscope, laser particle size analysis, X-ray diffraction and thin section microscopic identification. As the results show, vertically,there are three anomalously high permeability zones in the A₁¹, A₁² and A₂¹ micro-stage of the middle diagenetic stage, with the depth range of 2300 m ~ 2400 m, 2400 m ~ 2600 m, 2600 m ~ 2900 m respectively. Grain size, sorting, dissolution and early emplacement of hydrocarbons are the main causes of anomalously high permeability zones. Although both grain size and sorting affect porosity and permeability, the effect of grain size on permeability is stronger than sorting, and sorting has a stronger effect on porosity than grain size. Magmatic hydrothermal and organic acid promote dissolution and concomitant porosity and permeability increase by dissolving unstable minerals. The early emplacement of hydrocarbons retard the cementation and accompanying porosity and permeability reduction by reducing the water-rock ratio. Finally, sandstone reservoirs in the Ew₃ are characterized by anomalously high permeability zones.

为研究北部湾盆地涠西南凹陷涠洲12-X油田涠洲组三段（E w _{3 ）优势渗流通道，挖掘剩余油潜力。}采用常规岩心物性分析、扫描电镜、激光粒度分析、X射线衍射和薄片显微鉴定等手段，研究了涠洲组异常高渗带分布及成因。结果表明，在纵向上，A ₁ ¹、A ₁ ²和A ₂ ^{1有3个异常高渗透带。}中成岩阶段的微观阶段，深度范围分别为2300 m~2400 m、2400 m~2600 m、2600 m~2900 m。烃类的粒度、分选、溶解和早期就位是异常高渗透带的主要原因。虽然粒度和分选都会影响孔隙度和渗透率，但粒度对渗透率的影响比分选强，而分选对孔隙率的影响要强于粒度。岩浆热液和有机酸通过溶解不稳定的矿物促进溶解和伴随的孔隙度和渗透率增加。烃类的早期就位通过降低水岩比来延缓胶结作用和随之而来的孔隙度和渗透率降低。最后，E w _{3砂岩储层}以异常高渗透率区为特征。