The Wanganui Basin (also spelled Whanganui Basin) is an onshore-offshore basin on the North Island of

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

. The basin provides an important stratigraphic and palaeontological record of the late Neogene marine environment of New Zealand.

Location and setting

The Wanganui Basin is located on the west coast of the

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

of New Zealand, within the Manawatū-Whanganui and

Taranaki Taranaki is a regions of New Zealand, region in the west of New Zealand's North Island. It is named after its main geographical feature, the stratovolcano Mount Taranaki, Taranaki Maunga, formerly known as Mount Egmont. The main centre is the ...

regions. The basin is roughly oval, with the longer (approximately ) axis running west-south-west/east-north-east, and has a width of approximately . A little under half of the basin is onshore, extending inland around the lower reaches of the

Whanganui Whanganui, also spelt Wanganui, is a city in the Manawatū-Whanganui region of New Zealand. The city is located on the west coast of the North Island at the mouth of the Whanganui River, New Zealand's longest navigable waterway. Whanganui is ...

and

Rangitikei River Rangitikei may refer to the following in New Zealand: * Rangitīkei River, one of country's longest rivers * Rangitikei District, a district council in the Manawatu-Wanganui Region * Rangitīkei (New Zealand electorate), a current general electorate ...

s before terminating at the foot of the

North Island Volcanic Plateau The North Island Volcanic Plateau (often called the Central Plateau and occasionally the Waimarino Plateau) is a volcanic plateau covering much of central North Island of New Zealand with volcanoes, lava plateaus, and crater lakes. It contains t ...

. The southern half of the basin extends into the

South Taranaki Bight The South Taranaki Bight is a large bay on the west coast of New Zealand, south of Taranaki, west of the Manawatu, north and west of the western entrance of Cook Strait and north of the South Island. The name is sometimes used for a much smaller ...

. The major population centre within the basin is along the coast, around the city of

Geology

Stratigraphy

The Wanganui Basin is "one of the most complete late Neogene marine stratigraphic records in the world," and is an important region for geological and palaeontological research. The basin provides the basis for the eponymous Wanganui epoch in the

New Zealand geologic time scale While also using the international geologic time scale, many nations–especially those with isolated and therefore non-standard prehistories–use their own systems of dividing geologic time into epochs and faunal stages. In New Zealand, the ...

, which covers the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

and

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

over the last 5.33 million years. The series was first described in depth and compared to glacial cycles by Charles Fleming, which has had a lasting impact upon subsequent stratigraphic, palaeontological and palaeoecological research. Each stage within the Wanganui epoch is named after regions of the Wanganui Basin series.

Key sites

* Castlecliff * Nukumaru

Palaeontology

Sediments within the basin are rich with shallow marine invertebrate fossils, including

molluscs Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

and

bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic animal, aquatic invertebrate animals, nearly all living in sedentary Colony (biology), colonies. Typically about long, they have a spe ...

ns. The most common fossilized molluscan shells belong to the bivalve genera '' Dosinia'' and ''

Chlamys The chlamys (; genitive: ) was a type of ancient Greek cloak. It was worn by men for military and hunting purposes during the Classical, Hellenistic and later periods. By the time of the Byzantine Empire it was part of the state costume of the ...

'' and the gastropod genera ''

Zethalia ''Zethalia'' is a genus of sea snails in the subfamily Umboniinae of the family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other rela ...

'' and ''

Murex ''Murex'' is a genus of medium to large sized predatory tropical sea snails. These are carnivorous marine gastropod molluscs in the family Muricidae, commonly called "murexes" or "rock snails".Houart, R.; Gofas, S. (2010). Murex Linnaeus, 1 ...

''. Shells of ''

Aeneator An ''aeneator'' ( or ) was a specialized player of wind instruments who was attached to a Roman military unit. The word comes from Latin ''aēneus'' or ''ahēneus'', "brazen", from ''aes'', "copper alloy". While the size of individual Roman milit ...

'', ''

Buccinulum ''Buccinulum'' is a genus of sea snails, marine gastropod molluscs in the whelk family Tudiclidae.MolluscaBase eds. (2020). MolluscaBase. Buccinulum Deshayes, 1830. Accessed through: World Register of Marine Species at: http://www.marinespecies. ...

'', ''

Penion ''Penion'' is a genus of large marine (ocean), marine snails, commonly known as siphon whelks, classified within the mollusc family (biology), family Austrosiphonidae.MolluscaBase eds. (2021). MolluscaBase. Penion P. Fischer, 1884. Accessed throu ...

'', ''

Alcithoe ''Alcithoe'' is a genus of large sea snails, marine gastropod molluscs in the subfamily Cymbiinae of the family Volutidae, the volutes.Marshall, B. & Bail, P. (2015). "''Alcithoe'' H. Adams & A. Adams, 1853". In: MolluscaBase (2015). Accessed ...

'', and ''

Amalda ''Amalda'' is a genus of medium-sized sea snails, a marine gastropod mollusc in the family Ancillariidae, the olives and allies.Bouchet, P. (2014). Amalda H. Adams & A. Adams, 1853. Accessed through: World Register of Marine Species at http://ww ...

'' marine snails are also frequent.

References

{{coord, 40, 0, S, 174, 45, E, display=title Zealandia Geology of New Zealand Manawatū-Whanganui Paleontological sites of New Zealand

Location and setting

Geology

Stratigraphy

Key sites

Palaeontology

See also

References