湖相泥页岩脆性指数计算方法探讨与应用——以黄骅坳陷沧东凹陷孔二段为例  

Discussion and application of the calculation method or the brittleness index of flacustrine shale:Taking the Second Member of Kongdian Formation in Cangdong Sag,Huanghua Depression as an example

作　　者：王冠 刁丽颖 赵玥 杨飞 任仕超 WANG Guan;DIAO Liying;ZHAO Yue;YANG Fei;REN Shichao(Exploration and Development Research Institute of PetroChina Dagang Oilfield Company,Tianjin 300280,China;No.5 Oil Production Plant of PetroChina Dagang Oilfield Company,Tianjin 300280,China)

机构地区：[1]中国石油大港油田分公司勘探开发研究院,天津市300280 [2]中国石油大港油田分公司第五采油厂

出　　处：《录井工程》2021年第2期39-44,共6页Mud Logging Engineering

摘　　要：在评价湖相泥页岩脆性过程中,应用广义脆性指数计算结果值偏大,而应用狭义脆性指数计算结果值明显偏小,且二者均与实测工程力学脆性指数没有良好的对应关系,无法客观反映泥页岩的脆性特征。在对黄骅坳陷沧东凹陷孔二段泥页岩系统取样分析的基础上,通过建立岩石矿物成分与工程弹性参数之间的关系,确定了利用岩石矿物成分加权计算脆性指数的方法。岩石矿物成分与工程弹性参数计算的脆性指数回归可以得到泥页岩脆性指数计算公式,公式表明石英对脆性贡献最大,白云石、长石次之,方解石、黄铁矿、方沸石影响较弱,黏土对脆性贡献最小。利用该方法对沧东凹陷GA井孔二段进行计算,指导压裂方案设计,取得了良好的应用效果。When evaluating the brittleness of lacustrine shale,index calculated by generalized brittleness is too large,while that by narrow brittleness is obviously too small.Moreover,neither of them has a good corresponding relationship with measured engineering mechanics brittleness index,failing to objectively reflect the brittleness features of shale.Based on systematic sampling and analysis of the shale in the Second Member of Kongdian Formation in Cangdong Sag,Huanghua Depression,by establishing the relationship between rock mineral composition and engineering elastic parameters,a calculation method for brittleness index by weighting the rock mineral composition is determined.The calculation formula obtained by the brittleness index regression of rock mineral composition and engineering elastic parameters indicates that quartz contributes the most to brittleness,followed by dolomite and feldspar,calcite,pyrite and analcime have weaker effects,and clay contributes the least to brittleness.This method is used to calculate the GA well in the Second Member of Kongdian Formation in Cangdong Sag and guide fracturing scheme design,achieving good application results.

关 键 词：沧东凹陷 孔二段 泥页岩 脆性指数 矿物成分 弹性指数 

分 类 号：TE132.1[石油与天然气工程—油气勘探]