Collaborative RUI: Uranium-Series Constraints on Melting in the Jan Mayen Region

University Of Wyoming, Laramie WY

Investigators

Abstract

The Mid-Atlantic Ridge, particularly its segments in the Arctic Ocean north of Iceland, produce new crust that has a trace element-rich geochemical signature that differs from normal mid-ocean ridge basalts. This unusual chemistry is an enigma and its origins are disputed, with some evidence indicating that the lavas are of hotspot origin, but not related to the closest known hotspot which is under Iceland, and other evidence pointing to the melting of trapped subcontinental material resulting from the geologically recent opening of the Greenland Basin 53-55 million years ago. Resolution of this question impacts our understanding of the mantle with implications for other regions along the mid-ocean ridge system that experience anomalous volcanism such as the Azores and Ascension. This research examines geochemically anomalous lavas from Jan Mayen Island on the Kolbeinsey Ridge near Iceland to determine their source and the timing and mechanisms of melt generation and transport. Both in-hand samples and those to be collected on a German high-resolution field mapping cruise to the area will be analyzed for radiogenic isotopes (Sr, Nd, Pb, and Hf) and U-series isotopes. A better understanding of the region under investigation will provide important information about how melting occurs at depth and leads to volcanic activity. Broader impacts of the work include support of an early-career investigator from a group under-represented in the sciences at a women's liberal arts college and training of female undergraduate students in state-of-the-art high-end Uranium series dating techniques. The work also involves extensive international collaboration with Swedish, UK, and German scientists and cross training of students in other laboratories as well as having them participate in an international oceanographic cruise to the Arctic.