Task 3: To search for time and space patterns in the multiplicity of information in the SIL data

Start: June 1996 (month 4)
End: February 1998 (month 24)
Responsible partner: IMOR.DG
Cooperative partners: UUPP.DGEO, NVI

Results have been obtained on basis of investigation of recent high seismic activity near the Hengill triple junction in SW-Iceland, spatial and temporal variations of activity have been studied and migration within the area (Figure 4) [,].

  

Figure: Earthquakes in the Hengill volcanic area, SW-Iceland. The red lines show the location and orientation of fault planes estimated from the relative location of earthquakes. The black lines are mapped surface faults, green lines are roads. The inset rose diagram shows the orientation of the faults mapped using accurate relative locations of earthquakes.

The seismicity of Katla volcano which is beneath the Mýrdalsjökull glacier has been studied. Eruptions in Katla pose a considerable danger because of enormous water- and mudflows which accompany the eruptions. It is one of the objectives of the SIL network and the attached alert system to help to warn for the the future eruptions [33].

Spatial changes in seismicity have been studied in an area along the Reykjanes Peninsula, the South Iceland Lowland, into the eastern volcanic zone, and off coast of North Iceland [37,,].

Work has been carried out to find 3-D crustal velocity structure in SW-Iceland from local earthquake tomography in cooperation with UUPP.DGEO [86,].

Based on historical data and recent historical data research work has started on known earthquake premonitory changes [75].

Much work has been carried out in interpreting data from volumetric borehole strainmeters, which has lead to very significant results. Premonitory and coseismic changes, volumetric strain, and foreshocks of the magnitude 5.8 earthquake at Vatnafjöll, near the eastern end of the SISZ, have been studied. These can be interpreted and have been modelled as magmatic fluids intrusion coinciding with the foreshocks and the main shock [5,].