New K-Ar age determinations of basalt samples from three drill holes and outcrops on the Franz Josef Land suggest that flood volcanism throughout the archipelago fits in a very narrow age interval (116±5 Ma). For 95% of the samples we studied, age scatter is within analytical uncertainty. New data on basaltic bulk-rock, trace element, and REE compositions point to mantle plume affinity for Early Cretaceous magmatism on the Franz Josef Land, which preceded the onset of seafloor spreading in the Canada Basin.

Supplement to: Grachev, A F; Arakelyantz, M M; Lebedev, V A; Musatov, Evgeny E; Stolbov, N M (2001): New K-Ar ages for basalts from Franz Josef Land. Russian Journal of Earth Sciences, 3(1), 79-82