摘要
It′s a challenge for log evaluation in identifying the reservoir lithology and calculating the porosity of Fengcheng Formation in Wuerhe nose belt,northwestern margin of Junggar Basin.The conventional methods lose their roles in lithology identification and porosity calculation because of the complex lithology.Based on the optimization method and using the rock volume physical model,six kinds of minerals have been identified and the relative volume content for different kinds of minerals and formation porosities have been calculated.The reliability and dependability of this optimization method were verified by the comparison.The calculated results can offer faithful measurement parameters for effective reservoir identification and reserves calculation.