西南石油大学学报(自然科学版)

• 博导论评 • 上一篇    

川东北地区须三段钙屑砂岩储层特征及控制因素

司马立强*,袁龙,吴思仪,闫建平,曾志凌   

  1. 西南石油大学地球科学与技术学院,四川成都610500
  • 出版日期:2015-04-01 发布日期:2015-04-01
  • 通讯作者: 司马立强,E-mail:smlq2000@126.com
  • 基金资助:

    国家自然科学基金(41202110);西南石油大学校级科技基金(2012XJZ004)。

Reservoir Characteristics and Main Control Factors of Xu3
Member Calcarenaceous Sandstone in Northeast Sichuan Area

Sima Liqiang*, Yuan Long, Wu Siyi, Yan Jianping, Zeng Zhiling   

  1. School of Geosciences and Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China
  • Online:2015-04-01 Published:2015-04-01

摘要:

近两年川东北地区西北部多口井须家河组三段钙屑砂岩测试段获工业气流,表明了研究区储层的含气性及局
部具备油气富集高产的地质条件。通过储层岩性类型、储集空间、物性、电性等特征进行综合分析,得出结论为:主要
储层岩性类型为钙屑砂岩,常伴有微裂缝;储集空间类型多样,主要为残余原生粒间孔、次生溶蚀孔和裂缝;储层表现
为低孔、低渗特征;储层电阻率高,主要原因是碳酸盐岩含量高;储层测井响应为“三低、一高、一降低”,即伽马低值、
声波低值,中子低值,电阻率高值,在高阻的背景下深浅电阻率有所降低。研究区优质钙屑砂岩储层受储集层发育的
有利沉积微相、溶蚀作用、构造裂缝以及一定的储层厚度等综合因素控制。辫状河道、水下分流河道沉积为储层最有
利的沉积相带;在成岩过程发生的溶蚀作用和多期次的断裂影响下形成的构造裂缝都极大地改善了储层的渗透性;一
定厚度的储层改善了裂缝的连通系统。

关键词: 川东北地区, 钙屑砂岩, 微裂缝, 次生溶孔, 辫状河道

Abstract:

In the past two years,industrial gas flow was obtained in Xu3 Member calcarenaceous sandstones segment of Xujiahe
Formation of Northeast Sichuan Area,which suggests that reservoir in Xujiahe Formation of study area shall be hydrocarbon
and has the geological conditions ofhigh yield. We made analysis of the type of reservoir lithology,reservoir space,physical
property,electric property and so on. The researches show that lithology type of reservoir includes calcarenaceous sandstone,
often accompanied by microfracture. It has various pore space which mainly consists of residual original intergranular pore,
secondary dissolution pores and cracks. The reservoir shows low porosity and low permeability. Reservoir resistivity is high,
because of high carbonate content. The reservoir log response shows low GR,AC and CNL and high resistivity decreases under
the background of high resistance. The calcarenaceous sandstone reservoir in the study area is controlled by the comprehensive
factors such as favorable sedimentary microfacies,dissolution,structural fracture and reservoir thickness. The most advantageous
reservoir sedimentary micro-facies is braided river,underwater distributary channel;dissolution during the diagenetic
process and fracture under the influence of multiphase tectonic fissures greatly improves the permeability of reservoir;the certain
thickness reservoir improves the connectivity of fracture system,and is advantageous to oil and gas migration and gather
accumulation.

Key words: Northeast Sichuan Area, calcarenaceous sandstone, Xujiahe Formation, microfracture, secondary solution pores,
braided river