Identification of metamorphic rocks in the CCSD main hole

It is more difficult to identify metamorphic rocks than sedimentary rocks by well logs. In order to identify metamorphic rocks, eight types of well logs were chosen for the identification of metamorphic rocks in China Continent Science Drilling (CCSD) main hole. We use stepwise discrimination method to recognize metamorphic rocks. The first step is to establish Back-Propagation artificial neural network model to recognize general types of metamorphic rocks. Then the Bayes discrimination function was established to recognize detailed types of metamorphic rocks.