Dienstag, Feb 19, 2013
An increased number of earthquakes and possibly a weak tremor pulses appear on today's seismic recording. [mehr]
On 14 February GeoNet reported that Tongariro remained quiet with no eruptive activity being detected since the explosion on 21 November 2012. Steam-and-gas plumes rose from the Te Maari Craters, and were unusually strong during the recent weeks possibly due to weather conditions. The Aviation Colour Code remained at Yellow (second lowest on a 4 four-color scale) and the Volcanic Alert Level remained at 1 (on a scale of 0-5). [mehr]
Tongariro VulkanTongariro volcano is a large complex volcano with about 12 craters and vents, including the steep stratovolcano Ngauruhoe, which is the focus of most activity in recent times.
Tongariro with its colorful crater lakes, hot springs, fumaroles, numerous cones and lava deserts is one of the major tourist attractions of the North Island, and the famous "Tongariro crossing" is generally regarded as one of the most scenic hikes in the world.
Beschreibung:Tongariro is a large andesitic volcanic massif, located immediately NE of Ruapehu volcano, that is composed of more than a dozen composite cones constructed over a period of 275,000 years.
Vents along a NE-trending zone extending from Saddle Cone (below Ruapehu volcano) to Te Mari crater (including vents at the present-day location of Ngauruhoe) were active during a several hundred year long period around 10,000 years ago, producing the largest known eruptions at the Tongariro complex during the Holocene. North Crater stratovolcano, one of the largest features of the massif, is truncated by a broad, shallow crater filled by a solidified lava lake that is cut on the NW side by a small explosion crater.
The youngest cone of the complex, Ngauruhoe, has grown to become the highest peak of the massif since its birth about 2500 years ago. The symmetrical, steep-sided Ngauruhoe, along with its neighbor Ruapehu to the south, have been New Zealand's most active volcanoes during historical time.
6 August 2012 eruption
A brief but violent phreatic eruption occurred at 23:50 local time on 6 August from new vents near the Te Mari crater of Tongariro.
The explosion followed several weeks of increased earthquakes under the volcano. It produced a 7 km tall ash plume and threw ballistic blocks of up to 1 m diameter to 1.5-2 km distance.
An interesting news article with eyewitness accounts and other information: First Tongariro eruption in over 100 years ...mehr