Cambrian Lithostratigraphy Division and Comparison in Northwest China under the Time Scale with Four Series

Based on the comprehensive analysis of paleontology, isotopic ages and the contact relations between upper and inner lithostratigraphic units, and under the new global Cambrian framework with four series and ten ages, stratigraphic units of sixteen stratigraphic areas of northwestern China were redefined. By comparative study, the lithostratigraphy divison framework of northwest China was preliminarily established. This study would provide scientific evidence for stratigraphic studies in northwestern China.