Ruapehu - IGNS - Science Alert Bulletin V96/09
June 17 1996 (Monday) 0930 NZST (UT +12)
Change In Alert Status
At about 0630h this morning the level of volcanic tremor started to
increase again at Mt Ruapehu. Shortly afterwards (0650h) the first of
several eruption plumes was seen above the volcano. Larger eruption pulses
have been observed at 0710h and 0825h. The pulses rose to elevations of
several kilometres above Ruapehu carrying voluminous amounts of coarse
ash. Large blocks rising to heights of 400 to 500m metres have fallen to
distances of 600 and 700m from the vent. The second pulse which continues
to the present time has been accompanied by a small lahar down the
Whangaehu River valley. Ash fall has been recorded as far north as Turangi
due to the prevailing southerly wind.
At this time we have a scientist on a helicopter flight to make an
assessment at the volcano, and we will update the situation following
reports from the flight.
This activity follows intense volcanic tremor on Saturday
afternoon-evening and early on Sunday morning.
The Alert Level is now raised to 3, and will be reevaluated as more
information becomes available.
BJ Scott Mgr Volcano Surveillance
for CJN Wilson (Volcanology Programme Leader)