Determining Lithology of Igneous Rocks in Deep Northern Songliao Basin Using Correspondence Analysis

The lithology of igneous formations in deep Northern Songliao basin is very complex.There are various igneous rocks from basic to acidic,not only volcanic lavas,but also eruptive tuffs. The log responses of various igneous rock samples are used for correspondence analysis(CA).The important logs which are sensitive to lithologic changes are recognized and the characteristics of log responses of igneous rocks are summarized according to the results of CA.After applying Principle Component Analysis (PCA) to the data of the igneous samples selected according to borehole condition,the first and second principle components from logs are obtained. The igneous rocks of this area are classified depending on the first and second principle components using fuzzy cluster analysis.The recognized lithology is comparable with cores.