One (1) volcano-tectonic earthquake was located during this period at a depth of approximately 1.5 km (1 mile) just to the north of St George's Hill. Ten (10) long period events were recorded by most of the seismic stations in the network. Broadband tremor has been recorded on the Gages seismic station at various times during this period and occasionally at slightly higher amplitudes than of late. This broadband tremor is thought to be due to continued steam emissions at variable rates from the crater area.
The dry tilt network at Amersham was re-occupied today; this technique measures changes in shape of the volcano sourcing from deep beneath it. The data show that there has been no change since the network was last occupied in mid-October.
EDM measurements to the Castle Peak reflector show no change from yesterday; the lines from Amersham to Chances Peak steps are currently being measured and any changes on these lines will be reported tomorrow.
Visual observations made today from the helicopter although visibility was generally poor due to low cloud and steam in the crater area. No major changes in any part of the new dome were noted; an area on the north side of Castle Peak Dome still appears to be the most active at present. A small ash fall occurred overnight, depositing ash in some parts of Plymouth. This ash was probably produced as the result of a rock avalanche in the crater area and should be no cause for concern.