Jul 1 1996, 12:00 pm - Ruapehu Volcano

Seismic activity recorded at Dome remains at a low level. Small emergent events (which have been correlated with small ash eruptions on previous occasions) appeared on the Dome record this morning, along with a slightly increased number of small high frequency earthquakes, interpreted as occurring at shallow depths beneath the summit.

Reported (ground) observations indicate that Ruapehu has been emitting a white gas-rich plume during most of today. A small, ash-bearing, dark plume was reported observed from Whakapapa Village at about 11:45, although this plume could not be seen from Iwikau or Turoa, suggesting that it did not rise to high altitude. There was no unusual seismicity at this time, suggesting that the ash emission resulted from gentle degassing. Dark ash deposits observed on the fresh snow covering eastern slopes of Ruapehu indicate that similar small ash eruptions probably occurred during the weekend bad weather.

The alert level remains at 3. We intend to obtain another COSPEC measurement in the next 2 - 3 days, and to review the alert level when results are known (provided no change in eruptive activity has occurred).

Ian Nairn
Rostered Volcano Surveillance Manager