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Accessibility: WHEELCHAIR ACCESS
Castle and moat volcano
WHAT'S HERE?
Mt Robertson volcano in 1949 after the scoria cone crater had been enlarged, before quarrying of top
A castle and moat volcano that has been highly modified by quarrying of the scoria cone and housing developments on the tuff ring.
LEARN ABOUT IT
Playing field stadium in enlarged scoria cone crater.
Mt Robertson was named after the local European owner, by Hochstetter when he visited it in 1859. The land was donated to be a park by the Mayor of Otahuhu Alfred Sturges in the early 1900s and the park is named after him. This volcano is one of the least conspicuous volcanoes in Auckland. It erupted about 24,000 years ago.First eruptions were wet explosive (phreatomagmatic) and produced an 800 m wide explosion crater with surrounding tuff (layered ash) ring around the SW, S, SE and E sides.
Eruptions switched to dry magmatic with fire fountaining producing the small 28 m high central scoria cone that you parked on. The scoria cone had a 200 m wide crater that was widened and partly filled to produce the sports stadium in the 1930s-1940s. The top 5 m of the scoria cone was quarried away in the 1950s and 1960s creating the carpark on the south side and playing field on the north.
Parts of Great South Rd and Mangere Rd run along the crest of the tuff ring, and the floor of the southern half of the explosion crater has been turned into playing fields used by Otahuhu College. Otahuhu College is built on the gently sloping southern flanks of the tuff ring.
Eruptions switched to dry magmatic with fire fountaining producing the small 28 m high central scoria cone that you parked on. The scoria cone had a 200 m wide crater that was widened and partly filled to produce the sports stadium in the 1930s-1940s. The top 5 m of the scoria cone was quarried away in the 1950s and 1960s creating the carpark on the south side and playing field on the north.
Parts of Great South Rd and Mangere Rd run along the crest of the tuff ring, and the floor of the southern half of the explosion crater has been turned into playing fields used by Otahuhu College. Otahuhu College is built on the gently sloping southern flanks of the tuff ring.
HAVE A LOOK!
1960 vertical air photo of Mt Robertson volcano. Whites Aviation.
From the carpark can you makeout the tuff ring arc on the south and east sides of the playing fields in the explosion crater?
Can you imagine how high the scoria cone was before the quarrying and modification of the crater?
Can you imagine how high the scoria cone was before the quarrying and modification of the crater?
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Directions/Advisory
From Great South Rd in the middle of Otahuhu shops take Park Ave for 300 m to its end and drive into Sturges Park. Turn left around the crest of the scoria cone and park in the large carpark up there.
Watch out for cars in the park and carpark. Some of the scoria cone slopes can be steep and slippery when wet.
Google Directions
Accessibility:
WHEELCHAIR
The volcano can be viewed from the carpark or you can take a walk around the crest of the scoria cone mainly on the road, or walk down into the explosion crater (moat) on the south side to get a feel for the whole castle and moat volcano.
Features
Volcanic
Landform
Geological Age
Late Quaternary, erupted about 24,000 years ago.
Zealandia Evolution Sequence
Pākihi Supergoup: 5 million years ago – present
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