Lake Pupuke is a heart-shaped freshwater lake occupying a volcanic
explosion crater (or maar) between the suburbs of Takapuna and
Milford on the North Shore of Auckland, New Zealand.
Separated from the sea by less than 200 m at one point, it has a
circumference of about 4.5 km and reaches 57 m in depth.
It is popular for recreational activities and the lakefront
property around it.
Pupuke volcano is one of the oldest in the Auckland Field, possibly
as old as 150 000 years. It does not have the height people often
associate with a volcano because it is an explosion crater.
The Auckland Volcanic Field is comprised of monogenetic
volcanoes which means it is unlikely that Pupuke or any of the
existing volcanoes will erupt again. The next eruption will
probably occur in a new location.
Early eruptive activity at the Pupuke volcano (Lake Pupuke)
generated thin, overlapping lava flows. Lava flowing back down the
throat of the volcano probably formed the large collapsed crater.
Explosive eruptions then ejected ash, generated a low tuff ring
around the crater. The tuff ring slopes gently away from the
lake.
On the western flanks of the volcano, a small scoria mound was
formed from minor fire-fountaining of frothy lava. After the
volcanic activity ended, the crater filled with fresh water to form
Lake Pupuke.
Along the coast, many tree moulds (stumps and logs) are exposed
in the lava. This ancient fossil forest can be seen at the northern
end of Takapuna beach.
Other examples of explosion craters in Auckland are Panmure Basin
and Orakei Basin.
Lake Pupuke is a valuable recreational asset. It is used for
water sports such as small sail boating, kayaking, water skiing,
and fishing. In 1884 Lake Pupuke was used to provide a water supply
to Devonport Borough. The water supply quickly became insufficient
and the old pump house (now a theatre) ceased operation in
1944.
Key facts
Maori name: Pupuke, shortened form of Pupukemoana, 'over
flowing lake'.
Location: North Shore City, map reference NZMS 260:
R11/680896
Depth: 64m
Age: Formed 140,000-150,000 years ago
Volume lava: approximately 26 million cubic metres
(equivalent to 5,200 Olympic sized swimming pools)
Volume tuff/ash/pyroclastics: approximately 34 million cubic
metres (equivalent to 6,800 Olympic sized swimming pools)