Reply to comment on Long or short silicic magma residence time beneath Hekla volcano, Iceland? by Sigmarsson O, Bergþórsdóttir I A, Devidal J-L, Larsen G, Gannoun A

We would like to thank Geist et al. (Contrib Miner Petrol, 2023) for the opportunity to further discuss the arguments presented in our paper Long or short silicic magma residence time beneath Hekla volcano, Iceland? (Sigmarsson et al. Contrib Miner Petrol 177:13, 2022). The disagreement centers around the origin of the silicic magmas at Hekla, namely whether it is by (1) fractional crystallization and a long crustal residence time before eruption or (2) partial melting of altered basaltic crust and short transfer time to the surface. We disagree with the arguments presented by Geist et al. (Contrib Miner Petrol, 2023) against the model for the origin of dacite at Hekla from dehydration melting of amphibolite, a model that still explains most if not all results obtained so far on the Hekla magma suite.

Automated summary

This paper discusses the origin of silicic magmas at Hekla volcano and compares two different explanations. The authors argue that the dacite at Hekla volcano is formed through dehydration melting of altered basaltic crust, a model that can explain most of the observed results so far.