迈陈凹陷东部涠洲组储层特征及影响因素——以XW6油藏为例

Reservoir characteristics and influencing factors of Weizhou Formation in eastern Maichen Sag, Beibuwan Basin: A case study of reservoir XW6

陈平 马英俊 施琰 成为

Chen Ping Ma Yingjun Shi Yan Cheng Wei

中国石化 江苏油田分公司 勘探开发研究院, 江苏 扬州 225012

Exploration & Production Research Institute of SINOPEC Jiangsu Oilfield Company, Yangzhou, Jiangsu 225012, China

利用岩石铸体薄片鉴定、扫描电镜分析、X射线衍射分析等测试手段,以XW6油藏为例,对北部湾盆地迈陈凹陷东部涠洲组储层的岩石学特征、物性及孔隙结构特征及影响储层物性的主控因素进行了分析。结果表明,涠洲组储层物性总体较差,涠二段砂岩储层颗粒较细,分选中—差,以中孔—中低渗—中细喉类储层为主,储层物性相对较好;涠三段砂岩储层颗粒较粗,分选差,以特低孔、低孔—超低渗、低渗—细微喉类储层为主,储层物性相对较差。影响储层物性的因素有:压实作用是导致储层物性变差的主要原因;油气充注对溶蚀孔隙的形成和孔渗空间的保存起到了较好的作用;相同埋深情况下,沉积微相和岩石类型对储层的物性起着重要的控制作用。

The lithologic characteristics, physical properties, pore structure and their controlling factors of the XW6 reservoir in the Weizhou Formation in the eastern Maichen Sag were studied based on thin section observations, scanning electron microscopy and X-ray diffraction analysis. The physical propertiesof the Weizhou Formation aregenerally poor with the second member featuring fine grain size, medium-poor sorting, medium porosity, medium-low permeability and medium-narrow throat diameters. The third member has coarse grain size, poor sorting, ultra-low porosity, super-low permeability and microthroat diameters, indicating less favorable physical properties.The controlling factors for physical propertieswere summarized as follows. Compaction made the physical propertiesof the reservoir become worse. Hydrocarbon filling was beneficial for the generation of dissolved pores and the preservation of porosity and permeability. Sedimentary micro-facies and rock type played a very important role in reservoir physical properties.

中国石化股份公司项目"北部湾盆地中部地区油气成藏条件与勘探潜力"(P14088)和江苏石油勘探局项目"徐闻地区油气成藏综合地质研究"(JS13041)资助。

https://doi.org/10.11781/sysydz201504460