Deformation studies by repeated GPS measurements have been carried out in Iceland since 1986 by several groups. They have shown significant variability of deformation rates, both in time and space. This technique has successfully been used for deformation studies and modeling of rifts, transform and volcanic zones in Iceland. All GPS data previously acquired in Iceland potentially represent an opportunity to have a coverage of the deformation at a large-scale.
Semi-continuous GPS measurements at one SIL station in the South Iceland
seismic zone have shown the overall plate motion. Continuous GPS
measurements (CGPS) is an extremely valuable method to provide temporal
coverage of the deformation, in addition to borehole volumetric strainmeter
recordings. CGPS measurements have been initiated for seismic and volcanic
risk mitigation purposes at four sites in the Hengill area, Southwest Iceland.
Four other CGPS stations are planned in the seismic risk area near Húsavík, North Iceland, also for that purpose. Two CGPS stations in South Iceland are
currently operated by the IGS and EUREF permanent networks, for determining
coordinates and velocities of reference points and satellite orbits.
These new CGPS stations create a start, but an incomplete network
of CGPS in Iceland.
Because of the significant build-up and operation of
continuous deformation measurements already in the lowland seismic risk
areas of Iceland it is a scientific necessity to improve the infrastructure
with CGPS stations where we most probably could observe, localize, and
quantify the initial effects of crustal deformation related to the mantle
plume activity, that is near the Hotspot center, in the highlands.
To reach this goal we will start to collect and process data from
CGPS stations in Iceland and unite all ongoing CGPS networks in
We also propose to improve the infrastructure in the highlands and install
facilities to encourage scientists and surveyors
to temporarily leave their GPS
instruments in the network for semi-continuous measurements.