Banks Peninsula Volcano

Banks Peninsula Volcano
Stratigraphic range: Late Miocene (11–5.8 Ma however has earlier 98 Ma volcanics)[1] PreꞒ Ꞓ O S D C P T J K Pg N
Banks Peninsula with Akaroa Harbour (West, Lower) and Lyttelton Harbour (East, Upper)
Type	Volcanic Complex
Sub-units	Diamond Harbour Volcanic Group, Mount Herbert Volcanic Group, Akaroa Volcanic Group, Lyttelton Volcanic Group
Overlies	Torlesse Composite Terrane and Mount Somers Volcanics
Thickness	Originally c.1500m
Lithology
Primary	Basalt
Other	Andesite, trachytes and rhyolite
Location
Coordinates	43°44′58″S 172°52′10″E / 43.74944°S 172.86944°E / -43.74944; 172.86944
Map of South Island centred on Banks Peninsula. Clicking on the map enlarges it, and enables panning and mouseover of volcano name/wikilink and ages before present. Key for the volcanics that are shown with panning is:   basalt (shades of brown/orange),   monogenetic basalts,   undifferentiated basalts,   arc basalts,   arc ring basalts,   olivine (basalts shades of olive),   phonolite (pale salmon),   dacite,   andesite (shades of red),   basaltic andesite,   rhyolite, (ignimbrite is lighter shades of violet), and   plutonic or intusive (gray) - so dolerite/diabase/microgabbro will have shadings towards gray compared to erupted basalt.

The Banks Peninsula Volcano is an extinct volcanic complex to the east of Christchurch on New Zealand's South Island.^[2] While the volcano is highly eroded it still forms the majority of Banks Peninsula with a highest point of 919 m (3,015 ft).^[3] It is a composite of two main eruptive centres one originating at Lyttelton Harbour, the other at Akaroa Harbour. The eruptions were predominantly basaltic, with associated andesite and trachytes, with minor rhyolite. The volcanic activity occurred in the Late Miocene and possibly extended into the Early Pliocene. There are four volcanic groups, all of which are within the Māui Supergroup.^[4] The Christchurch earthquakes led to rumors of a possible eruption, however, there is no known magma chamber beneath the volcano and there has not been any sign of volcanic activity in the last 5 million years.^[5]