Aug 5 1996, 3:00 pm - Ruapehu Volcano

Tremor levels at Dome were very low until about 20:00 yesterday, when they increased to moderate levels, continuing until about 07:00 this morning. Bursts of moderate amplitude tremor which occurred during this period appear to have accompanied ash emissions, although these were not observed due to bad weather. Very light overnight ash fall has been reported from Napier. very light ash fall was occurring on the Desert Road at 11:00 this morning, while tremor was at low-moderate level. Continuing bad weather this morning has prevented visual observations of the volcano summit.

A discrete earthquake at 06:04 this morning was recorded occurring close to Dome. It appears similar to the earthquake which accompanied a landslide on April 21 this year. Coincidentally, the Tranzrail lahar warning gauge on the Whangaehu River was triggered at Level 1 at 09:00 this morning. This would be an appropriate travel time for a lahar generated at about 06:00, but Tranzrail staff reported no sign of a high river level after inspection of the gauge at about 10:30 this morning. They regard the alarm as a malfunction.

The COSPEC gas flight originally planned for August 1 still has not occurred due to the poor weather conditions.

The Alert Level remains at 3.

Ian Nairn
rostered Volcano Operations Manager