Dun Mountain–Maitai terrane

{{Short description|Geological feature in New Zealand}}

{{Use dmy dates|date=July 2022}}{{Use New Zealand English|date=December 2024}}

{{Infobox rockunit

| name = Dun Mountain–Maitai terrane

| image = Dun mountain Nelson New Zealand.jpg

| caption = View of Dun Mountain in Nelson for which the terrane is named

| type = Terrane

| age = Early Permian-Triassic
~{{fossil range|280|200}}

| period = Permian

| prilithology = Basalt, gabbro, peridotite, sedimentary rocks

| otherlithology = Jade

| namedfor = Dun Mountain & Maitai River

| namedby =

| region = Nelson, Tasman, Marlborough, Otago & Southland Regions

| country = New Zealand

| coordinates =

| unitof = Austral superprovince

| subunits = Dun Mountain ultramafics group, Livingstone volcanic group, Maitai group and Otanomomo complex

| underlies = Murihiku Terrane, Momotu & Haerenga Supergroups

| overlies = Caples Terrane

| thickness =

| extent =

| area =

| map = File:Map New Zealand Geology.jpg

| map_caption = Components of the Dun Mountain-Maitai terrane are coloured green in this map. Light green (10) are Permian ophiolites and pyroclastics and dark green (11) are Permian volcanic rocks. Adjacent are more recent greywacke light blue (2), schists dark blue (3), and the most recent sedimentary deposits are yellow (1).

}}

The Dun Mountain–Maitai terrane comprises the Dun Mountain ophiolite belt (also called the mineral belt), Maitai group, and Patuki mélange.{{cite journal|last1=Mortimer|first1=N|last2=Rattenbury|first2=MS|last3=King|first3=PR|last4=Bland|first4=KJ|last5=Barrell|first5=DJA|last6=Bache|first6=F|last7=Begg|first7=JG|last8=Campbell|first8=HJ|last9=Cox|first9=SC|last10=Crampton|first10=JS|last11=Edbrooke|first11=SW|last12=Forsyth|first12=PJ|last13=Johnston|first13=MR|last14=Jongens|first14=R|last15=Lee|first15=JM|last16=Leonard|first16=GS|last17=Raine|first17=JI|last18=Skinner|first18=DNB|last19=Timm|first19=C|last20=Townsend|first20=DB|last21=Tulloch|first21=AJ|last22=Turnbull|first22=IM|last23=Turnbull|first23=RE|title=High-level stratigraphic scheme for New Zealand rocks|journal=New Zealand Journal of Geology and Geophysics|volume=57|issue=4|year=2014|pages=402–419|issn=0028-8306|doi=10.1080/00288306.2014.946062|doi-access=free}} The Dun Mountain Ophiolite is an ophiolite of Permian age located in New Zealand's South Island. Prehistorically this ophiolite was quarried by Māori for both metasomatized argillite and pounamu (jade) which was used in the production of tools and jewellery.{{cite journal | last1 = Walls | first1 = J. Y. | year = 1974 | title = Argillite quarries of the Nelson mineral belt | journal = New Zealand Archaeological Association Newsletter | volume = 7 | issue =1 | pages = 37–43}}

In the late 1800s, the Dun Mountain ophiolite belt was surveyed for its economic potential. During this time the rock types dunite and rodingite (after Dun Mountain and the Roding River) were first named.{{cite journal | last1 = Johnston | first1 = M. R. | year = 2007 | title = Nineteenth-century observations of the Dun Mountain Ophiolite Belt, Nelson, New Zealand and trans-Tasman correlations | url = http://sp.lyellcollection.org/content/287/1/375.abstract | journal = Geological Society, London, Special Publications | volume = 287 | pages = 375–387 | doi=10.1144/sp287.27| bibcode = 2007GSLSP.287..375J }} Discovery of economic deposits of chromite near Nelson lead to the building of New Zealand’s first railway, however, extraction only occurred between 1862 and 1866. In the 20th century, serpentinite was mined for fertiliser and the ophiolite remains one of New Zealand's main sources of pounamu (jade), but all other mineral exploration has failed to find economic deposits.