Acquisition and Commissioning of a Carbonate Preparation Device for Stable Isotope Analysis

点击翻译按钮获取中文摘要

This project supports the purchase, installation, and commission of a new computer-automated device that dissolves fossil shells and other mineral materials made of calcium carbonate, to prepare them for specialized analysis of their carbon and oxygen isotopic composition at high precision. The investment in this equipment enhances the analytical capabilities of a stable isotope facility that is used by a large community of US scientists and will facilitate a broad range of experiments for decades. Isotopes of carbon in fossil shells are useful as a chemical fingerprint of how carbon moves between various forms such as carbon dioxide in the atmosphere, dissolved carbon in the ocean, and as carbon incorporated into organic materials formed by plants and animals. Isotopes of oxygen are typically used to trace changes in physical environments, such as past temperature changes, and movement of water through evaporation, rain, or snow, growth or melting of glaciers, and freshwater flows into the ocean. This is important for fundamental understanding of the natural interactions between climate and life on earth, and provides scientific background for policy interests of the United States related to changes in natural environments. The equipment supports education and training of students, including experiential learning in STEM fields. The Kiel-IV high-vacuum acid-digestion device acquired through this project is enabling new research directions and improves the analytical capabilities of the Oregon State University/College of Earth, Ocean, and Atmospheric Sciences Stable Isotope Laboratory for measuring oxygen and carbon isotopes in ultra-small samples of carbonate (such as fossil foraminifera and other biogenic carbonates). The instrument is attached as an inlet system to an existing ThermoFisher 253Plus isotope-ratio mass spectrometer. This new equipment serves a large community of NSF-funded investigators, so will facilitate many projects. Primary applications are in paleoclimatology and paleoceanography. The equipment is also used in STEM experiential learning for students at the undergraduate and graduate levels. Over the past five years, more than 100 students from institutions throughout the US have used the existing facility; educational opportunities are expected to grow as the facility is updated with modern state-of-the-art equipment.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.