测井识别庐枞矿集区科学钻探ZK01孔复杂岩性

Well-logging identifying the complex lithology of scientific drilling ZK01 at Luzong ore concentration area

庐枞矿集区位于长江中下游成矿带内,ZK01孔为深部探测项目在该地区布设的一口科学钻探孔.地球物理测井利用各种仪器在钻孔中连续观测,获取了钻遇地层的视电阻率、极化率、密度、自然伽马、纵波速度和磁化率等物性参数.该孔钻遇岩性复杂,测井曲线难以直接识别岩性,本文基于交会图等技术分析各种岩性测井响应特征,提取各种岩性的物性特征值,建立了砖桥组和岩体组相关岩性的Bayes自动判别模型,其回判正确率分别为85.1%和83%,并在实际判别中取得了较好的应用效果.

Luzong ore concentration area is locating in the middle and lower reaches of the Yangtze River,and ZK01 borehole,a scientific drilling hole, is belonging to the deep exploration projects. With continuous observation in the borehole carried by various instruments, Geophysical logging has obtained several physical parameters like resistivity,polarizability,density,natural gamma,P-wave velocity and magnetic susceptibility,etc. Owing to the complex lithology,it is difficult to directly identify lithology with logging curves, and the paper is to analyze lithological logging response characteristics and then obtain various of physical properties value of the lithology through cross-plot technology,at the same time,building two automatic Bayes lithology identification models： Zhuanqiao formation and Bedrock formation, whose accuracy reaches 85. 1% and 83% respectively and achieves an effective application.