Quantifying Diachroneity and Refining Biostratigraphy in the Mid-Latitudes: Integrating Foraminiferal and Nannofossil Records from the Northwest Pacific

Authors: Helena Kwarteng, Adriane Lam

Field of Study: Science, Technology, Engineering, and/or Math

Faculty Mentors: Adriane Lam

Easel: 1

Timeslot: Midday

Abstract: Accurate age models are essential for reconstructing past oceanographic conditions, refining the geologic time scale, and guiding resource exploration. Planktic foraminifera and calcareous nannofossils remain the most reliable tools for first-order age control due to their widespread distribution and rapid evolution. While tropical-subtropical biozonation schemes are well-documented for the Cenozoic, their applicability to mid-latitudes is uncertain due to regional oceanographic variations and species' diachroneity. In the Northwest Pacific, previous studies have documented diachroneity in planktic foraminifera, but no work has investigated nannofossil diachroneity. This study will address this gap by examining whether similar diachronous trends exist in nannofossils and quantifying such diachroneity. This presentation will focus on Site 1208, located under the modern position of the Kuroshio Current Extension, to determine the degree of diachroneity of calcareous nannoplankton compared to species’ calibrated ages from other parts of the world ocean.