Montserrat Volcano Observatory


Daily Report
Report for the period 16:00 on 14 Jan. 1996
to 16:00 on 15 Jan. 1996


Seismicity during the past twenty four (24) hours was generally similar to that during the past several days in being dominated mainly by repetitive hybrid earthquakes. The period 16:00 to 20:00 on January 14 saw the occurrence of a thirty minutes long episode of low amplitude broadband tremor, a few highly emergent signals probably representing small ash eruptions, two (2) small volcano-tectonic events and very small hybrid earthquakes. At about 20:12 on January 14, a small long period event was followed by five successive seismic signals which probably represent small eruptions and several more of these were recorded up to midnight. From midnight to about 14:00 on January 15, repetitive hybrid events occurred at a rate of about 1 - 3 per minute, with amplitudes considerably smaller that those recorded during the previous 24 hours. Several moderate-sized long period events also occurred during this period. After 14:00, the repetitive hybrid events decreased considerably. The events from January 13 are still being processed but today's hybrid events will be too small to locate individually, although they are likely to be occurring at a shallow depth beneath the crater area. Several small ash eruptions occurred and one at 15:20 today resulted in light ash fall in Plymouth.

EDM measurements were made today on the Lower Amersham to Upper Amersham and Lower Amersham to Chance's Peak Steps. No significant change within the errors of the technique was noted from previous occupations for both of these lines.

No visual observations were made today because of the low cloud cover blanketing the volcano. A number of small ash eruptions were generated by rock falls from the area of active dome growth.


Montserrat Volcano Observatory