In October 2019, the Rosselia samples were collected from outcrops beside the Da'an River in Taiwan, belonging to the early Pliocene Yutengping Sandstone Member of the Kueichulin Formation. Samples of the Rosselia were analyzed to explore the potential of the Rosselia as a natural archive for recording paleoenvironmental shifts in seabed sediment origin. Organic carbon measurements (total organic carbon or TOC; and the stable isotopic signature δ13C) were collected from the samples to understand the compositional shifts in the concentric lamination of the Rosselia. An elemental analyzer (Flash EA, Thermo) connected with an isotope ratio mass spectrometry (Delta V, Thermo Finnigan) were used to analyze TOC and δ13C of hand-drilled rock powder samples of the lamination.