The High Arctic Large Igneous Province (HALIP): A study in geochemistry and variations in
lithospheric thickness
D.M. Dockman
The High Arctic Large Igneous Province (HALIP) is a remote and understudied magmatic
province centred on the Queen Elizabeth Islands that extends to Svalbard (Norway), northern Greenland,
and Franz Josef Land (Russia). Magma generated during Late Cretaceous rifting, which separated these
once adjacent islands, is manifested as dykes, sills, and lava flows. Due to complicated logistics and short
field seasons in the high arctic, relatively little research has been done on the HALIP compared to other,
more accessible, large igneous provinces around the world. Current geological maps of arctic Canada
seriously underrepresent the amount of magma that exists in the north, mapping only the sediments and
leaving the high volume of magma as a footnote.
All the samples collected for this study are from dykes and sills on the margin of the Mesozoic
Sverdrup Basin on Ellesmere and Axel Heiberg Islands. Preliminary geochemical results show a basaltic
to mildly alkalic composition. This study will use the rare earth element (REE) chemistry of the magmas
as a proxy for the depth of magma generation during Late Cretaceous extension. The depth at which the
magma formed gives a snapshot of how thick the lithosphere was at the time of magma emplacement.
Using an existing REE inversion model on related nephelinites from Bathurst Island as another depth
marker, a cross-section of Cretaceous lithospheric thickness can be created from the thick cratonic
lithosphere of mainland arctic Canada to the thin, extended Sverdrup Basin on the northern tip of
Nunavut.