摘要
为了正确认识渝东南地区下寒武统牛蹄塘组黑色页岩储层特征与主控因素,对采自渝科1井和酉科1井的岩心样品,进行了系统的黏土矿物及全岩X-射线衍射分析、岩石常规物性分析、比表面和孔径分析、岩石有机碳分析、镜质体反射率(R_o)及显微组分测试。测试分析结果表明:牛蹄塘组页岩储层碎屑矿物含量平均为51.34%,黏土矿物含量平均为32.74%,有效孔隙度平均为1.2%,渗透率平均为8.0×10^(-3)mD,属于特低孔、特低渗储层。孔隙以中孔为主,约占总孔体积的73%。BET(Brunauer、Emmett和Teller)比表面积平均为7.75 m^2/g,平均孔直径为5.3 nm。总有机碳含量(TOC)平均为2.29%,R_o平均为3.12%,属于过成熟阶段。进一步统计分析表明:TOC与微孔体积呈正相关,黏土矿物总量与之呈负相关;TOC、黏土矿物总量、碳酸盐矿物含量均与中孔体积呈正相关;TOC、碳酸盐矿物含量均与宏孔体积呈正相关,碎屑矿物含量与之呈弱的正相关,黏土矿物总量与之呈负相关。用常规测井方法对牛蹄塘组页岩的孔隙度和TOC进行了计算,发现利用中子曲线计算的孔隙度与岩心分析结果在两口井中均吻合较好,但浅层不含油气情况下,自然伽马曲线(GR)与岩心分析TOC之间无明显相关关系。
To correctly recognize reservoir characteristics and their controlling factors of the Lower Cambrian black shales of Niutitang Formation in southeast Chongqing, the following tests are systematically performed on the core samples collected from Well Yuke 1 and Well Youke 1, including clay minerals and whole rock X-rays diffraction analysis, and analyses on common petrophysical properties, pore size and specific surface area, organic carbon in rock, vitrinite reflectance （Ro） and maceral composition. The test results show that the average content of detrital minerals and clay minerals in the shale reservoirs of Niutitang Formation is 51.34% and 32.74%, and the average effective porosity and permeability is 1.2% and 8.0×10-3 mD respectively, demonstrating these reservoirs are of ultra-low porosity and permeability. Moreover, mesopores as the main type account for 73% of the total pore volume. The average BET （Brunauer, Emmett and Teller） specific surface area is 7.75 m2/g, and the pore diameter is 5.3 nm~ the total con- tent of organic carbon （TOC） has an average of 2.29%, and the average Ro is 3.12%, indicating that the shale reservoirs are in the over-mature stage. Further statistical analysis shows that TOC is positively correlated with micropore volume, while the total con- tent of clay minerals is negatively correlated with it; TOC, the total content of clay minerals and the content of carbonate minerals are positively correlated with mesopore volume; TOC and the content of carbonate minerals are positively correlated with macropore volume, and the content of detrital minerals has weakly positiue Correlation with it, whereas the total content of clay minerals is neg- atively correlated with it. The TOC and porosity of shales in Niutitang Formation are calculated using conventional logging method. It is discovered that the porosity calculated according to the neutron curve fits well with core analysis results in both Well Yuke 1 and Well Youke 1. However, in the shallow layers without gas and oil,
出处
《石油学报》
EI
CAS
CSCD
北大核心
2014年第2期233-244,共12页
Acta Petrolei Sinica
基金
高等学校博士学科点专项科研基金优先发展领域课题"中国南方海相富有机质页岩天然气吸附机理与储气性能研究"(20120022130001)
国土资源部全国页岩气资源战略调查项目(2009GYXQ15-04)资助
关键词
页岩
储层特征
多元线性回归
牛蹄塘组
渝科1井
shale
reservoir characteristics
muhiple linear regression
Niutitang Formation
Well Yuke 1
