Melt movement through the Icelandic crust. ...

We use both seismology and geobarometry to investigate the movement of melt through the volcanic crust of Iceland. We have captured melt in the act of moving within or through a series of sills ranging from the upper mantle to the shallow crust by the clusters of small earthquakes it produces as it...

Full description

Bibliographic Details
Main Authors: White, Robert S, Edmonds, Marie, Maclennan, John, Greenfield, Tim, Agustsdottir, Thorbjorg
Format: Article in Journal/Newspaper
Language:English
Published: The Royal Society 2019
Subjects:
Online Access:https://dx.doi.org/10.17863/cam.30426
https://www.repository.cam.ac.uk/handle/1810/283064
Description
Summary:We use both seismology and geobarometry to investigate the movement of melt through the volcanic crust of Iceland. We have captured melt in the act of moving within or through a series of sills ranging from the upper mantle to the shallow crust by the clusters of small earthquakes it produces as it forces its way upward. The melt is injected not just beneath the central volcanoes, but also at discrete locations along the rift zones and above the centre of the underlying mantle plume. We suggest that the high strain rates required to produce seismicity at depths of 10-25 km in a normally ductile part of the Icelandic crust are linked to the exsolution of carbon dioxide from the basaltic melts. The seismicity and geobarometry provide complementary information on the way that the melt moves through the crust, stalling and fractionating, and often freezing in one or more melt lenses on its way upwards: the seismicity shows what is happening instantaneously today, while the geobarometry gives constraints averaged ...