Mt Tongariro

‘Tongariro is not a simple mountain, but a highly complex volcanic system’

Bernard Friedlander (1898)

Five key concepts

• Draw a table into your booksTen Key Concepts for Mt Tongariro

Cones

• Ngauruhoe is one of the many cones of Tongariro, it has been built by a large number of eruptions

Vents

• Many of Tongariro’s explosions vents are active, with Ngauruhoe being the most active

Craters• The central and south craters of Tongariro are now

believed to be depressions and not explosion centres, so are not true craters

Dykes and Sills• The unusual feature in the Red crater is a dyke• Sills and dykes may help to reinforce the structure of the

volcano, but may in time be exposed by erosion• The feature in the yellow oval is a dyke

– The magma rose to the surface through a crack and sank again without reaching the surface

– Lava cooled and hardened on the outside but the centre retreated, leaving it hollow

– The dyke was revealed when the surface of the crater was eroded

Hot springs and fumeroles

• Magma sometimes takes thousands of years to cool and remains just below the surface

• The escaping gases heat ground water and generates steam

• Ketetahi springs, Te Mari and Red craters are examples

Mt Ruapehu

• Why is Mt Ruapehu the most ‘hazardous’ mountain in the TVC?

• Use text from page 27, 28, 29, 30 to write answering – Why is Mt Ruapehu the most hazardous volcanic cone in

the TVC?– How may these hazards be minimised?

• 1,000 – 1,500 words• Pick out bullet points from the text first• Organise ideas into paragraphs• Then write into essay form with intro, body and

conclusion• These will be marked, hand in on Wed 26/03/08

Essay