Sæl öll,
Assuming that epicentral locations are accurate, the ongoing icequake swarm at
Skeiðarárjökull is occurring within the subglacial catchment of Súla.
For the latest epicentres, see: http://hraun.vedur.is/ja/viku/2004/vika_42/bab.gif
This suggests that either a minor jökulhlaup from Grænalón is in progress, or
that rainfall within the last 24 hours has caused increased sliding at the
glacier bed. Skeiðarárjökull has received at least 40-mm of rainfall since
~08.00 hours yesterday, so we presently suspect that rainfall is forcing the
seismicity, either directly due to meltwater reaching the glacier bed, or
indirectly through rainfall-induced leakage from Grænalón. Rainfall is
expected to intensify over Skeiðarárjökull today.
If seismicity levels increase, or if new epicentres appear on the eastern side
of Skeiðarárjökull, then we will send another up-date.
Með bestu kveðjur,
Matthew Roberts og Halldór Geirsson
Eðlisfræðisviði, VÍ
