|Region:||Iceland and Arctic Ocean|
|Measurement method(s):||InSAR, GPS - continuous, GPS - campaign, Levelling, Strainmeter, Tiltmeter, EDM|
|Duration of observation:||2009 to 2011 (published results); continuous|
|Inferred cause of deformation:|
|Characteristics of deformation:|
Michalczewska et al. (2011) show continuous inflation the Krísuvík geothermal area in early 2009 using continuous GPS and ENVISAT InSAR data. The authors show that uplift “continued until fall of 2009 when the area began to subside reaching the pre-inflation state in early spring 2010. In April 2010 another uplift episode started”. Up to 2011, the inflation continued at a comparable deformation rate to the pre-deflation one.
In 2011, the Krísuvík area was monitored with continuous and campaign GPS measurements and InSAR. The deformation registered by the GPS stations suggests an inflation source at 4-5 km depth located beneath Sveifluháls area, with uplift rates exceeding 50 mm/yr at stations closest to the inflation center, just north of Seltún geothermal area. TerraSAR-X data indicate the extent of the uplift.
Seismic activity in the Krísuvík area over two years (~2009-2011?) indicate more frequent earthquakes during the inflation periods while fewer during the deflating phase. The authors show that the earthquakes lineate a N-S trending structure and coseismic GPS displacements suggest right lateral rupture on a N-S trending strike-slip fault.
From Guðjónsdóttir (2014): “Recent studies of resistivity measurements in the Krýsuvík system have shown signals of a deep seated conductive body at approximately 2 to 5 km depth, (Didana, 2010). This body is located near the central part of the Krýsuvík geothermal area with an approximate size of 10 km2 and coincides well with an inflation source at 4-5 km depth as suggested by GPS recordings (Hersir et al., 2013).
The Icelandic Meteorological Office (IMO) leads long-term monitoring of geohazards in Iceland and is responsible for maintaining instrument networks for this purpose. FutureVolc detail a description of in-situ monitoring networks in Iceland and available results. In-situ instrumentation to monitor geological hazards in Iceland includes seismic, GPS, strain, hydrological, radar, infrasound networks, and scanning DOAS spectrometers. With InSAR, the volcanoes in Iceland are not covered by a single systematic study but 85% of them have been included in separate studies of volcanic, seismic, cryospheric or geothermal processes (Biggs et al., 2014).
|Reference:||Smithsonian Institution Global Volcanism Program |
|Reference:||Michalczewska, K., S. Hreinsdottir, T. Arnadottir, S. Hjaltadottir, T. Agustsdottir, M. T. Gudmundsson, H. Geirsson, F. Sigmundsson, G. Gudmundsson (2011) Inflation and deflation episodes in the Krisuvik volcanic system (abstract V33A-2843), Fall AGU|
|Reference:||Didana, Y, L., 2010. Multidimensional Inversion of MT data from Krýsuík high|
temperature geothermal field, SW-Iceland, and a study of how 1D and 2D inversion can
repoduce a given 2D/3D resitivity structure using synthetic MT data. Unpublished MS
thesis, University of Iceland, Reykjavik, 119 pp.
|Reference:||Hersir, G., Árnason, K., Vilhjálmsson, A., 2013. 3D inversion of Magnetotelluric (MT)|
resistivity data from Krýsuvík high temperature geothermal area in SW Iceland.
PROCEEDINGS, Thirty-eighth workshop on Geothermal Reservoir Engineering, Stanford
University, Stanford, California, February 11-13, 2013. SGP-TR-198. 14 pp.
|Reference:||Guðjónsdóttir, S. R. (2014). Gas emissions from the Krýsuvík high-temperature geothermal system, Iceland.|
View of Krisuvik volcano. Source: Smithsonian Institution Global Volcanism Program
Sourced from FutureVolc (http://futurevolc.hi.is/volcanoes-and-monitoring): “Iceland: volcanoes and present long-term monitoring stations. The volcanic areas consist of volcanic systems, made of central volcanoes, calderas and fissure swarms. Western Eastern, and Northern volcanic zones marked (WVZ, EVZ, NVZ) are located on the divergent plate boundary between the North-American and Eurasian plates. Iceland’s most active volcanoes are Grímsvötn (G) and Bárðarbunga (B) under the Vatnajökull ice cap, Katla (K) under Mýrdalsjökull ice cap, and Hekla (H). Eyjafjallajökull vocano is labelled E”.