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Index Geophysics

Gravity and elevation changes caused by magma movement beneath the Krafla Caldera, Northeast Iceland

Item

Title (Dublin Core)

en-US Gravity and elevation changes caused by magma movement beneath the Krafla Caldera, Northeast Iceland

Description (Dublin Core)

en-US Prior to the present activity of the Krafla volcano, which started in 1975, levelling and gravity surveys had been carried out in the area. The network has since been extended, and measurements are carried out about every second month. The measurements reveal a quasi-periodic behaviour of the tectonic activity, characterized by slow inflation of the caldera for several weeks or months at a rate of 6–10 mm/d, interrupted by sudden subsidence events lasting for one or a few days. Elevation changes within the caldera are described by a deflation-inflation swelling with its apex near the center of the caldera. Calculations. using a model of a spherical chamber with varying pressure at 3 km depth, show good agreement with the measured elevation values. Comparison of gravity and levelling data, using a Bouguer type relationship, suggests that inflation and deflation of the floor of the caldera is caused entirely by in- and outflow of magma. Some discrepancies between the levelling and gravity data immediately after subsidence events can be explained by additional mass flow of groundwater.
        ARK: https://n2t.net/ark:/88439/y037843
Permalink: https://geophysicsjournal.com/article/99
 

Creator (Dublin Core)

Johnsen, G.Y.
Bjornsson, A.
Sigurdsson, S.

Subject (Dublin Core)

en-US Gravity
en-US Elevation changes
en-US Magma flow
en-US Iceland
en-US Current rifting episode
en-US Geodesy

Publisher (Dublin Core)

en-US Journal of Geophysics

Date (Dublin Core)

1980-01-24

Type (Dublin Core)

info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
en-US Peer-reviewed Article

Format (Dublin Core)

application/pdf

Identifier (Dublin Core)

https://journal.geophysicsjournal.com/JofG/article/view/99

Source (Dublin Core)

en-US Journal of Geophysics; Vol 47 No 1 (1980): Journal of Geophysics; 132-140
2643-2986
2643-9271

Language (Dublin Core)

eng

Relation (Dublin Core)

https://journal.geophysicsjournal.com/JofG/article/view/99/61