Boggust Park Crater
Encyclopedia
Boggust Park Crater is a volcano
in Auckland
, New Zealand
. Located in the Favona
area of the Mangere
suburb, it is one of Auckland city's older volcanoes. It was first recognised as a volcano in 2011. The park in which it is located is named after Ralph Boggust, former superintendent of Manukau Parks Dept.
The volcano has a 300–400 m diameter crater
surrounded on three sides by a 6–8 m high semi-circular tuff ring with steep inner slopes and gentler outer slopes. In places the crest of the tuff ring has been flattened off by bulldozing during subdivision in the 1990s. The tuff ring is breached to the north-east, presumably by the sea during the Last Interglacial warm period
, about 130,000 years ago, when the sea level was 5–6 m above the present. The present floor of the crater is about 5 m above present high tide level and slopes down to the edge of Harania Creek estuary on the Manukau Harbour
. After eruption, Boggust Crater would have become a freshwater lake, before it was breached by the sea to become an intertidal lagoon
for a few thousand years, rather like Panmure Basin
today. The sea level dropped about 120,000 years ago and the crater became a swampy depression until 1 m of fill was added and drainage installed to make it a recreational sports field.
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...
in Auckland
Auckland
The Auckland metropolitan area , in the North Island of New Zealand, is the largest and most populous urban area in the country with residents, percent of the country's population. Auckland also has the largest Polynesian population of any city in the world...
, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. Located in the Favona
Favona
Favona is mostly industry-dominated suburb of Auckland, New Zealand, and is part of the Mangere area. The suburb is in the Manukau ward, one of the thirteen administrative divisions of Auckland city, and is under governance of the Auckland Council....
area of the Mangere
Mangere
Māngere is one of the larger suburbs in South Auckland, in northern New Zealand.The suburb is located on flat land at the northeastern shore of the Manukau Harbour, to the northwest of the centre of Manukau city and 15 kilometres south of Auckland city centre...
suburb, it is one of Auckland city's older volcanoes. It was first recognised as a volcano in 2011. The park in which it is located is named after Ralph Boggust, former superintendent of Manukau Parks Dept.
The volcano has a 300–400 m diameter crater
Volcanic crater
A volcanic crater is a circular depression in the ground caused by volcanic activity. It is typically a basin, circular in form within which occurs a vent from which magma erupts as gases, lava, and ejecta. A crater can be of large dimensions, and sometimes of great depth...
surrounded on three sides by a 6–8 m high semi-circular tuff ring with steep inner slopes and gentler outer slopes. In places the crest of the tuff ring has been flattened off by bulldozing during subdivision in the 1990s. The tuff ring is breached to the north-east, presumably by the sea during the Last Interglacial warm period
Interglacial
An Interglacial period is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age...
, about 130,000 years ago, when the sea level was 5–6 m above the present. The present floor of the crater is about 5 m above present high tide level and slopes down to the edge of Harania Creek estuary on the Manukau Harbour
Manukau Harbour
Manukau Harbour is the second largest natural harbour in New Zealand by area. It is located to the southwest of the Auckland isthmus, and is an arm of the Tasman Sea.-Geography:...
. After eruption, Boggust Crater would have become a freshwater lake, before it was breached by the sea to become an intertidal lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
for a few thousand years, rather like Panmure Basin
Panmure Basin
The Panmure Basin, also sometimes known as the Panmure Lagoon, is a tidal estuary within a volcanic crater or maar in New Zealand's Auckland Volcanic Field. It is located to the south of Panmure town centre....
today. The sea level dropped about 120,000 years ago and the crater became a swampy depression until 1 m of fill was added and drainage installed to make it a recreational sports field.