UNIVERSITY PARK, Pa. — What does research about the early Earth, the tectonics of the Alps and the collapse of ancient mountains have in common? Understanding of all these important Earth processes can benefit from an advanced mineral dating technique conducted in a new Penn State facility for the first time.
Using equipment in a new laboratory funded by Penn State, geoscientists are able to measure the age of rocks using a process that analyzes the atomic proportions of uranium and lead in the mineral zircon.
“This is exciting because this technique really supports a significant part of our research,” said Andrew Smye, assistant professor of geosciences. “A majority of what geoscientists know about how old the Earth is — the geological time frame, the evolution of Earth and its history — really is pinned to the absolute timing of geological events. And so having the capability to determine the age of key samples in-house is a real step forward.”
The new geochronology lab uses a laser ablation unit to drill into individual mineral grains much smaller in thickness than a human hair. Those samples are then fed into two mass spectrometers, which measure the isotopic composition of the minerals found in the rock. Zircon is typically used because it can accurately and reliably be dated using the uranium-lead decay scheme.