U‐Pb Geochronology and Lu‐Hf Isotopic Characterization of the Canadian High Arctic Large Igneous Province (HALIP): Comparison to Oceanic Plateau Magmatism

Abstract Recent high‐precision geochronological studies have delineated three main pulses of basaltic magmatism between ca. 130‐80 Ma in the Cretaceous High Arctic Large Igneous Province (HALIP) in northern Canada. Here we report new U‐Pb TIMS baddeleyite and zircon dates for samples from Axel Heiberg and Ellesmere Islands, which further support the duration and pulsed nature of the magmatism previously documented. We add new LA‐ICPMS U‐Pb zircon dates on samples analyzed in a previous study to help resolve age heterogeneity observed in some samples. We also report the first LA‐ICPMS zircon Lu‐Hf results from HALIP intrusives to better constrain the HALIP mantle source composition. Initial εHf zircon results for five HALIP basalts with minimal evidence for continental crustal contamination from the Canadian Arctic Islands range from +9.0 to +14.7, and indicate extraction from a depleted mantle source similar to plume‐derived oceanic plateaux such as Kerguelen.