Eruption age of the Sverrefjellet volcano, Spitsbergen Island, Norway

• Published in: Polar Research
• Main Author: Allan H. Treiman
• Format: Article in Journal/Newspaper
• Language: English
• Published: Norwegian Polar Institute 2012
• Subjects: Svalbard; Spitsbergen; basalt; Knipovich Ridge; Ar–Ar; geo; archeo; Norway; Svalbard Archipelago; Sverrefjellet; Polar Research
• Online Access: https://doi.org/10.3402/polar.v31i0.17320; https://doaj.org/article/06de31fc436d49448e97274ebde19f1b

Sverrefjellet is a Pleistocene-age basaltic volcanic construct on north-western Spitsbergen Island (Svalbard Archipelago, Norway). Published ages for the Sverrefjellet eruption range between 6000 years and ca. 1 million years before present. The age of eruption is dated here as 1.05±0.07 (1σ) My, consistent with Ar–Ar isochron and plateau ages of several analysed samples. Radiogenic Ar represents a small proportion of the released Ar, 40Ar/36Ar = 295.5), low-temperature alterations (Ar release at low temperature, with high Cl/K), carbonates and zeolites (Ar release at intermediate temperature) and xenolithic material (Ar release at high temperature, high Ca/K). The effects of the largely non-radiogenic argon sources are also seen in the total-gas Ar–Ar “ages”, which range from 1.3 to 10.3 My, significantly larger than the inferred eruption age. It is likely that total-gas Ar–Ar “ages” and whole-rock K–Ar “ages” of similar basalts also exceed their true eruption ages.To access the supplementary material to this article please see Supplementary files under Article Tools online.