movement between the two plates sometimes causes earthquakes.
In this area the center of the earthquakes is usually very deep
so violent quakes are not typical. Above the edge of the diving
Pacific Plate - about 75km underground by this stage - there are
a line of volcanoes. They run in a north easterly direction
from Ruapehu to Taupo, Rotorua, and onwards through White Island.
an eruption, as the Magma rises, gas is released in a similar
way to opening a soft drink bottle. The amount of gas varies according
to the makeup of the magma and is one of the things that give
a more energetic eruption. On your visit to Lake Taupo, try throwing
one of the beach rocks into the water - they float! The pumice
rocks from Lake Taupo are very porous, suggesting an extremely
violent eruptions. There are a few other clues to the violence
of Lake Taupo's eruptions, like the size of the hole it has left
behind - the lake is the same size as Singapore!