Seismicity during the past 24 hours has been of a variable nature with long period earthquakes still the most dominant feature. The larger long period earthquakes (magnitude 1.0 to 1.5) were located, at depths of between 0.2 and 0.9 km, beneath the crater area. Numerous other long period earthquakes, which are too small to locate, occurred at a rate of approximately one per minute throughout the review period. The low to moderate level broadband tremor, observed at 16:00 yesterday, increased in amplitude at approximately 13:30 today (29 February) and has continued until the end of this present review period. Two small volcano-tectonic earthquakes were detected, on the seismograph stations nearest to the volcano, at 22:23 on 28 February and at 00:16 and 09:42 on 29 February; they were all located at shallow depths beneath the volcano. Other seismic signals, associated with rock fall events, were detected throughout the review period. The largest of these signals occurred at 09:18 this morning; a light ash fall was reported after this event. The Montserrat seismic network also recorded a magnitude 3.5 regional earthquake at 18:06 last night, 28 February, with a location approximately 200 km southwest of the island.
EDM measurements were done at the eastern and northern triangles of the volcano today under good viewing conditions and once again there were no significant changes between the measured lines.
Visual observations were made in the early afternoon from the helicopter in good conditions. Rock falls indicative of continued dome growth were seen in the central and western parts of the dome.