Taking the temperature of the Anahim Hotspot, British Columbia
Date
2024
Authors
Murray, Paige L.
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Journal ISSN
Volume Title
Publisher
University of Victoria
Abstract
The Northern Cordilleran Volcanic Province is a 1200 km long and 400 km wide group of more than 100 mapped occurrences of volcanism throughout BC. There are several proposed hypotheses for the origin of volcanism: lithospheric extension, subduction and slab window formation, and migration of North America across a hotspot. Lava samples with olivine phenocrysts and Cr-spinel inclusions were collected from the volcanic centres to test whether the lavas are of a hotspot origin. This was done using LA-ICP-MS and electron microprobe to gather geochemical data from the samples. The chemical data was then used to derive the temperature the olivine and lavas crystallized at, which was used to calculate the mantle potential temperature for each volcanic centre. Potential temperatures of the volcanoes were compared to potential temperatures of known world hotspots and were found to be significantly (~200°) cooler, implying the lavas are likely not of a hotspot origin.
Description
Keywords
Olivine, basalt, geothermometry, Anahim Volcanic Belt, Anahim hotspot, mantle potential temperature