Abstract: Radioisotope multichannel X ray fluorescence method is a kind of nuclear geophysical prospecting technique with high speed, non destruction of samples, low cost and multi element analysis. By using this technique, the radioactive intensities of Ca, Fe, and Ba elements are measured from the Jialingjiang Formation of the Lower Triassic in the Miaoba section, Huayingshan region. The results of measureement are successfully applied to the study of chemostratigraphy and sequence stratigraphy, which shows wide application perspectives of this method.