UEDIN.DGG: University of Edinburgh, Department of Geology and Geophysics

UEDIN.DGG was responsible for Subproject 3, Shear-wave splitting to monitor in situ stress changes before earthquakes and eruptions. The contractor was Stuart Crampin. UEDIN.DGG has fulfilled its commitments in the workprogramme as a whole. However, frequent earthquakes in the Hengill-Ölfus area in SW-Iceland made it significant to change the emphasis of individual tasks to be carried out. This was reflected later in this report, in detailing the work carried out. All the problems addressed in the workprogramme are however addressed in the work carried out. The emphasis on continuous survey of temporal variations of shear-wave splitting from local earthquakes at a few stations in SW-Iceland has shown that it may be possible in many cases to see stress changes related to build-up of earthquakes or volcanic eruptions. In particular, observed temporal variations in shear-wave splitting in SW-Iceland was a basic observation in the successful forecast of the time and magnitude of a magnitude M=5 earthquake in SW-Iceland in November 1998. The success of this Subproject in explaining the relation between shear-wave splitting variations and effects of stress changes, as well as the successful stress forecast has initiated a new EU project within "Support for research infrastructures" (SMSITES: Developing stress monitoring sites and infrastructure for forecasting earthquakes, contract no. EVR1-CT1999-40002), which began on January 1, 2000. In all tasks above there was a close cooperation with IMOR.DG as concerns basic evaluation of and in providing data and applying the forecasts.