The overriding of the L uzon volcanic arc atop the underlying C hinese rifted‐continental margin has caused the formation of the T aiwan mountain belts and a peripheral foreland basin west of the orogen since the late Miocene. In this study, lithofacies analysis and calcareous nannofossil biostratigraphic investigations of the Dahan River section in northwestern ( NW ) T aiwan were performed. Our results offer insights into th...