Bill Haarlow ’25



Project Title

Metal Isotopes in Ancient Carbonates

I gathered data about various isotopes in ancient carbonates, including lithium, carbon and oxygen, to study how their concentrations changed over time and with ocean depth. These ancient carbonates included limestones and dolomites from around the world, ranging from formations in the United States to the middle of the Pacific Ocean. The carbonate rocks studied may preserve information from ancient surface environments about their local climate and ecosystems and may thus serve as proxy archives of paleoclimate at various times in the ancient past. We used column chromatography and mass spectroscopy to determine the compositions and concentrations of isotopes within the carbonates. The isotopic records for many different elements are incomplete due to the recency of the work. It was awesome to work with people at the cutting edge of the field. Through this internship, I gained experience in experimental design and learned to use common technology used in the field, including automatic ion chromatography machines, ion columns and mass spectroscopy machines. These skills will be useful in my ongoing research projects at Princeton and my future career.

Internship Year


Project Category

Climate and Environmental Science


Higgins Lab, Department of Geosciences, Princeton University - Princeton, New Jersey


John Higgins, Professor of Geosciences; Matthew Nadeau, Ph.D. candidate, Geosciences