| Abstract |
Surface manifestations at Red Crater,. Mt Tongariro, consist of steaming ground, a few fumaroles (T max = 94.5"C) and numerous steaming vents. The steaming ground covers a total area of about 8000 m2. Cooled condensates enriched in Si02 drain into the Oturere Valley. The total natural heat loss at Red Crater was estimated to be about 20 MW. Steaming ground in the Te Mari craters covers an area of about 3000 m2; maximum temperatures of 95.5"C were observed in most of the steam vents. The natural heat loss is of the order of 5 MW. Steam discharged in both areas is at local boiling point temperature. The manifestations at Red Crater, in the Te Mari craters and the Ketetahi fumarole field (36 MW) are fed by steam escaping from the Tongariro geothermal system, a vapour dominated system which underlies the three thermal areas. |