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Geology of New Caledonia

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Fig. 1 A simplified geological map of New Caledonia with a cross-section, modified by Xu and Liu (2019)[1]

The Geology of New Caledonia includes all major rock types (igneous, sedimentary, and metamorphic), which here range in age from ~290 million years old (Ma) to recent.[2] Plate collisions, rifting and erosion have been the major driving forces to form those rocks and to shape the island group.[2] The mantle-derived Eocene Peridotite Nappe is the most significant and widespread unit (labelled as "Ophiolites" and coloured in bright green in Fig. 1).[2] The unit consists of ore-rich ultramafic rocks thrust onto the main island, hence the mining industry for valuable metals has been an economical pillar of New Caledonia for more than a century.[3][2]

Currently, New Caledonia is located on the Indo-Australian Plate and the largely submerged continent of Zealandia.[4] After New Zealand, it is the second-largest subaerial landmass, and the Northernmost part of this continent.[4] As shown on the map, the landmass is elongated in a NW-SE orientation, which is similar to the distribution patterns of the most geological units. With Mont Panié and Mount Humboldt on the main island (as shown in Fig. 1) being the highest points (over 1,600 m), they provide insight to the rugged topography of the region largely caused by thrusting.[5]

Overview of the regional geology

Topographic map of New Caledonia and the neighboring Vanuatu.

The geology of the Collectivity is divided into two relatively separated parts: the larger Grande Terre in the West and the Loyalty Islands in the East.[2] The smaller islands are younger and are believed to emerge as a volcanic island arc in the Eocene, but is currently covered by coral reefs/ carbonate rocks.[2] For the main island of the Grande Terre, there are diverse geological units. Before illustrating each of them and their implications, here is the table to summarize the units in a reversed chronological order, as the older rocks usually occupy deeper locations:

Brief summary of the rock units on Grande Terre
Geological unit Rock type Formation process/ environment Time of emplacement Ref.
Nepoui series,

Gwa N'doro Formation

Clastic sedimentary Lagoonal to fluvial deposition Since Neogene [2]
[6]
Granitoids Felsic to intermediate intrusive igneous Intrusive volcanism to form plutons and dykes Eocene to Oligocene
Pouebo Terrane,

Diahot Terrane

Foliated metamorphic Subduction zone metamorphism Eocene
Poya Terrane,

Peridotite Nappe

Mafic to ultramafic intrusive and extrusive igneous Volcanism in the ocean, then obducted onto the island during collision between tectonic plates
Montagnes Blanches Nappe,

Bourail Flysch,

Koné Terrane,

Koumac Terrane,

Formation à charbon

Sedimentary Terrestrial towards marine, and back to lacustrine sedimentation Late Cretaceous to Eocene
Boghen Terrane Foliated metamorphic Subduction zone metamorphism Jurassic to Cretaceous
Teremba Terrane,
Central Terrane 		Mostly sedimentary Mainly marine sedimentation Permian to Early Jurassic
Koh Ophiolite Mafic to ultramafic intrusive and extrusive igneous Volcanism beneath the ocean, then transported and scrapped off during collision between tectonic plates Early Permian

In the Permian, the Island was initially located in the Southeastern Margin of the huge supercontinent of Pangea, and then in the united Southern continent of Gondwana.[2] Rocks in Koh-Central, Teremba and Boghen Terranes on the island suggest they were formed in a forearc basin with collisional tectonic movements.[2] That means the geological materials were emplaced and compressed along the plate boundary (between a volcanic arc and the associated subduction zone).

From the Upper Cretaceous to Eocene, proto-New Caledonia transformed into an extensional tectonic setting.[2] It is evidenced by a series of marine sedimentary rocks, and can be regarded as a miniature of rifting within Zealandia, and even the partition of Zealandia from Gondwana.[2] Northern Zealandia separated into the Lord Howe Rise in the East and the narrow strip of Norfolk Ridge in the West, of which New Caledonia is the Northernmost tip.[7] The New Caledonia Basin hence formed between the two blocks, but is still believed to be continental, though highly extended.[7][8] Just like the Lord Howe Rise, the Norfolk Ridge extend from Grande Terre towards New Zealand in the South via its namesake, the Australian Norfolk Island.[7]

The position of New Caledonia (top) in Zealandia

However, these were followed by a new collisional event. The abyssal lithosphere East of Grande Terre subducted under an oceanic plate in the East in the South Loyalty Basin.[2] Hence, the associated volcanism during the Eocene is believed to have created the sinuous volcanic island arc of Loyalty Islands/Ridge as the smaller part of the territory.[2] The epoch also oversaw a series of displacement of the oceanic lithosphere onto the East of the continental Norfolk Ridge.[2] One of the products of these dynamic events is the famous and economically significant Peridotite Nappe.[2][9][10][11][12][13]

After that, the country rocks were intruded by granitoids.[14] Since then, the Island re-emerged from the Pacific due to some minor movements.[2] Processes like exhumation, erosion and shallow-sea sedimentation are recorded by series of fossil-bearing lagoonal and fluvial sedimentary rocks.[2][6] Currently, Grande Terre is surrounded by a barrier reef with a length of 1600 km, thus forming the largest lagoon globally.[15]

Nowadays, the two ridges are generally parallel to each other and connect with the d'Entrecasteaux Ridge in the North.[16] Meanwhile, the North Loyalty Basin is sandwiched by the Eastern side of the Loyalty Ridge, as well as the New Hebrides Trench, where the Australian Plate subducts under the micro New Hebrides Plate.[17] Such plate motion makes the Loyalty being often suffered from earthquakes.[18]

Notably, the French territory also administers two tiny islands on the New Hebrides Plate − Matthew Island and Hunter Island, though disputed.[19] Therefore, their geology is rather related to the archipelago of Vanuatu, which also claims the active volcanic islands with andesitic composition.[19]

Petrology

Grande Terre

Koh-Central and Teremba Terranes

In the fore-arc basin tectonic setting, the suite of Koh Ophiolite is known to be the first terrane to be formed on the island in the early Permian.[9] It is unusual that the unit actually was created by two tholeiitic magmatic episodes, and is divided by a layer of boninite.[20] The older and lower layers are therefore intruded by the younger evolved tholeiite as dykes and sills.[20] The rock suite reveals a supra-subduction setting, where the materials from the oceanic lithosphere were scraped off and retained in the basin during the start of subduction.[21][9] By the U/Pb SHRIMP analysis, its own formation can be traced back to as early as Carboniferous.[21]

The Koh Ophiolite is overlain by a series of sedimentary rocks formed in a marine setting: black shale, greywacke, siltstone and chert.[2][22] Greywacke in there bears some pyroclastic characteristics, which is consistant with the fore-arc setting.[2]

Meanwhile, the clastic and volcanic rocks of Teremba Terrane formed between the Permian and Early Jurassic.[2] The clastic one is mainly greywacke, which could share the same source as those in the Koh-Central Terrane;[23] the composition of the volcanics varies from rhyolitic to andesitic.[2] They are slightly deformed into very-low-grade metamorphic rocks in zeolite facies.[2]

Through basin analysis, it is believed that the two terranes are a pair of "twins": they formed simultaneously, with the former one being formed offshore and the latter one in an onshore setting.[2]

Boghen Terrane

The Boghen Terrane is another group of rocks that formed in that period (Jurassic-Cretaceous).[2] It is basically composed of schists, with the grade ascending from greenschist to blueschist metamorphic facies towards the West.[24] With the protoliths being rocks like tholeiitic basalt and chert, these hint an oceanic origin of the rock, but materials from land or a volcanic arc are also mixed into the rocks.[25]

Their regoliths contain both oceanic and terrigenous material, including volcanic arc detritus, deposited as an accretionary complex.[2] Likely due to a Westward plate subduction, the complex further metamorphosed under high pressure but low temperature in the Late Jurassic to form blueschist.[2][25][26][24]

Nowadays, alongside Koh-Central and Teremba Terranes, the three terranes are found to be lying on the island in a sub-parallel and elongated pattern.[2]

Sedimentary rocks from Upper Cretaceous to Eocene

Sedimentary settled during this period followed a retrogradational parasequence (towards a deep marine environment with the trend of finer sediments).[2] Sandstone, coal-bearing siltstone and tuff as the record of minor volcanism, are among the first rocks formed in the setting.[2][27] Such group is called Formation à charbon, and shares an angular unconformity with the underlying older terranes.[2] Zircon analysis of the Formation reveals that the source of the clasts shall be from the 3 pre-Late Cretaceous Terranes.[27] Presence of angiosperm fossils and coal proved at least some parts of the Island already emerged from sea surface by the Late Cretaceous.[6] However, a shift of fossil records to marine bivalves and gastropods indicate the subsidence of the landmass to turn the sedimentary environment into an estuarine one.[6]

Formation à charbon is overlaid by the Paleocene Koumac Terrane, with the majority of sedimentary black chert and also some argillite.[2][28] Collectively known as phtanites, they mark the complete submergence of New Caledonia.[2] On the other hand, the gradual replacement of siliceous content by calcitic micrite signals a Northward drift of the continent, where a warmer climate favours deposition of calcite.[2]

In Eocene, on one hand there is an abrupt change of white micrite into pink marl, followed by the deposition of limestone breccia and conglomerates in the North of the Island.[2] Such turbidites and coarse-grained rocks collectively form the Bourail Flysch.[29] These all indicate an uplift of the crust, by a shift of the marine sedimentary records into a lacustrine one.[2] On the other hand, the presence of the unconformable shallow-water limestone with the same age represents a constant marine environment.[2] Their erosion is believed to be the result of the emersion because of fore-arc bulge linked to the new subduction zone.[2] The limestone is overlaid by a 3-to-5-km thick turbidite.[2]

"Montagnes Blanches" Nappe and Koné Terrane

The Nappe is a sedimentary rock sequence from argillite, chert, micrite and calci-turbidite, and was formed between the Late Cretaceous and Eocene.[2] Pierre Maurizot, the namer of the Nappe, modelled the younger flysch thrust over the native flysch in the Northern part of the Island to the south to form this newly defined allochthonous unit.[7] It is therefore systematically intercalated between the sedimentary rocks mentioned above, and the overlying obducted ophiolite units across the Island.[7]

The Montagnes Blanches Nappe is also overlain by Koné Terre, which is a pelagic unit of siltstone, argillite and chert.[2] Its presence or exposure is limited to Koné and Koumac, and has been overthrust by the Poya Terrane.[2]

Poya Terrane and the Peridotite Nappe

The two units collectively form Tethyan-style ophiolites.[10] The underlying Poya Terrane is located on the Western coast, pillow and massive undepleted mid-oceanic ridge basalts (MORB) are found with uplifts of m- to km- scale of thickness.[2][21][30] K-Ar dating suggest their age to be 61-38 Ma.[2]

The upper Peridotite Nappe not only covers a quarter of the surface of the landmass, but also spreads to the offshore Southern part of the Norfolk Ridge.[11] In particular, the large exposure of the unit in the South is known as "Massif du Sud", where profitable metal ores are enriched.[2] As the name suggests, peridotite, particularly harzburgite and lherzolite, are the major components, and are overlain by some dunite and wehrlite.[2][31] Such composition suggests the unit is originated from the uppermost part of the mantle and overthrusted the terranes below, including the Poya Terrane.[2] This is supported by the crustal gabbronorites at the flat top of the Nappe.[28] Yet, sheeted dykes and pillow basalt layers are absent above the gabbro, which is unusual for an ophiolitic suite.[12] The fault caused by overthrusting is therefore formed with a dip of 20°, with the presence of porphyroclastic mylonite to mark the shear zone.[2] It is further crosscut by varied types of the younger intrusive rocks, for instance, the sheared mafic amphibolites and felsic granitoids.[14][32] It has currently been heavily eroded and leached as laterite, with number of endemic flora only found on the rare ultrabasic leached product.[33][34][2]

Their presence is unusual already, as oceanic lithospheres should have subducted rather than obducted onto less dense continental basements under the ordinary circumstances. Moreover, since their relative positions are reversed compared to the other ophiolitic suites, their genetic relationships are disputed.[35][36] One of the explanations is that during the uplift by compression, the top mafic Terrane slid off by faulting and gravity onto the Norfolk Ridge, followed by the ultramafic Nappe.[36] This is based on a lack of obduction-induced thickening or deformation in the Nappe.[36]

Simplified cross-sectional evolution of the Eocene and granitoid units with respect to New Caledonia tectonics at that period, modified from Cluzel et al. (2005 and 2012), Patriat et al. (2018).[14][2][11] Things are not drawn to scale.

The two units sandwich another two formations: the Nepoui Flysch and Koumac Olistostrome.[2] The former one is thinner with biocalcarenite at the bottom, then argillite, arenite and dolomicrite.[2] Originated from the Poya Terrane, the arenite contains clasts of clinopyroxene, ilmenite and magnetite.[2] The latter one's thickness is about 300m, with the sequence from the bottom as the mass flow breccia along some dolomicrite, then peridotite-associated sands.[2] These may represent the marine deposition above the Poya Terrane before obduction.[2]

Eocene metamorphic complex

The complex consists of two parts: the Pouébo and Diahot Terranes.[2] They both have experienced clockwise P/T paths of metamorphism with similar age (44-34Ma), which is typical for metamorphic rocks that formed along a subducting slab.[2] With the forming conditions of high pressure but low temperature, it is therefore believed to be formed together with the detached Australian slab of the oceanic lithosphere, right before the obduction of the Eocene ophiolite.[2]

Sharing the same sedimentary sequence, the Diahot Terrane is regarded as the metamorphosed layer of the Montagnes Blanches Nappe and the Koné Terrane.[2] The Terrane itself consists of blueschist and eclogite in albite–epidote–omphacite, as well as ferroglaucophane–lawsonite mineral zones.[37] Such mineral assemblage helps the estimation of the burial depth to be 50km.[2]

As the Pouebo Terrane is formed deeper in the mantle (80km), the rocks have a higher-grade garnet-bearing greenish eclogite and glaucophanite.[2][28] It also contains eclogitic mélange that is believed to be originated from the dragged-down and the subduct part of the Poya Terrane.[2] [38]

Models suggest the complex have isostatically rebounded to form the Mount Panie antiform during an extensional event with Diahot in the West, and Pouebo in the East, after obduction later on.[2][11] This could indicate a renewed compression afterwards.[39]

Eocene dykes and Oligocene plutonic rocks

After the obduction event, there were several intrusions of granitoid magmas into the allochthon that could be initiated by the subduction of the New Caledonia Basin.[14] Some form dykes in Eocene to crosscut the Peridotite Nappe, while the others form plutons in Oligocene.[2] The dykes' composition varies from dioritic to trondhjemitic.[34] The plutonic magmas were heterogeneous in composition, possibly related to the post-obduction detached slab.[2][14] Moreover, their presence could imply a short-lived post-obduction reactivated subduction from the East due to compression.[14] The composition of the plutons ranges from high-K to medium-K calc-alkaline, hence forming granodiorite and adamellite.[2][14]

Rock formations since Miocene

Sedimentary rocks of the Nepoui Series are spotted in places like Nepoui Bay, which include lagoonal limestone, calcareous sand to slightly unconformable conglomerate and sands again.[2] Re-emergence of plant fossils after obduction is spotted in the latter layer.[6] The regolith pebbles in the conglomerate are well-rounded and cover and consists of pre-existing local rocks like peridotite.[2][40] Similar conglomerates and breccias are also found in the Gwa (or Goa) N'doro Formation near Houaïlou, and represents the remnants of a river network developed since Miocene.[2][40][28] These all witness the uplift, erosion, then deposition of the Island since Oligocene.[2][15]

In Quaternary, wind-transported aeolianites and the barrier reef is developing the coastal area, as the newest formations above the sea level.[40]

Loyalty Islands

Compared to Grande Terre, the islands are the younger part of the territory with no common geological units between them. The islands and the submerged parts of the Loyalty Ridge are overlain by Miocene carbonate sedimentary rocks, as well as modern coral reefs.[2] These makes investigations on its formation more complicated, but geophysical and bathymetrydata found the seamounts are just similar to the other island arcs.[2] Moreover, Eocene andesitic rocks have been drilled there, while ocean island basalt (OIB) on Mare Island hints the Islands could represent a North-South trending hotspot.[2] Combining the features of the subduction-obduction complex on Grande Terre, the explanation of the island arc is more likely. Although their formation is disputed, it is believed the recent forearc bulge of the Vanuatu arc in the Northeast has led to their uplift and emergence.[2] That means the crust is shortened and thickened due to great compressional force as the subduction zone is nearby.

Tectonic evolution

Simplified tectonic evolution of New Caledonia; not drawn to scale, and only related continental blocks are colored. Modified from Cluzel et al. (2012).[2]

By observing the properties and also the age of the rocks in different terranes, the tectonic evolution of the region can be reconstructed into three phases, with each phase illustrated in the sections below.[2]

Pre-Early Cretaceous subduction of Phoenix Plate

The first phase starts from the Permian to the upper Cretaceous and is also known as the Gondwana Phase.[2] Combined analysis of the three terranes suggests the proto-New Caledonia formed at the Eastern edge of a supra-subduction-related volcanic forearc.[2][21] In particular, the supra-subduction zone type Koh ophiolite marks the initiation of the subduction.[9] The subduction of the volatile-bearing slab then caused partial melting, leading to volcanic eruptions, as evidenced by the Teremba volcanic rocks.[2] Indeed, during that period, the extinct Phoenix Plate subducted under the united Southern continent of Gondwana.[41] Related magmatism persisted until mid-Cretaceous time.[27] Also, as the deep-sea sedimentary rocks show, the region was located at Southeast-Gondwana marginal basin system that opened between the Permian and the Cretaceous, with Australia being the source of the sediments.[2] Yet, fossil records also reveal part of the landmass was already terrestrial by the Late Jurassic.[6]

Rifting from Upper Cretaceous to Eocene

Simplified map of New Caledonia tectonics in Eocene, modified from Cluzel et al. (2019) and Patriat et al. (2018).[2][14] For the cross-section, please refer to the graph in the sub-section "Poya Terrane and the Peridotite Nappe".

In the Late Cretaceous, marginal rifting occurred on the Island, led to the complete submergence of the Island.[2][6] On a macro-scale, as evidenced by the presence of endemic fossil species, Zealandia drifted away from the rest of Gondwana, particularly the Australian land mass.[2] These are probably accommodated by the trench rollback of the previous subduction zone.[42][43] Units like the Formation à charbon and the Koné Terrane are all consistent to the hypothesis that Grande Terre laid on a passive margin.[2][6] Meanwhile, the Boghen Terrane's high-pressure schists exhumed due to rifting and unloading.[2]

Subductions and obduction in Eocene and Oligocene

Entering the Eocene, the presence of the subduction-obduction complex suggests a sequence of a new intra-oceanic subduction zone with dextral components.[2][13] The interception of the trench and the Norfolk Ridge evolved into Grande Terre.[13] The basaltic Poya Terrane and the South Loyalty Basin can be interpreted as the forearc, with an extinct trench along the Basin, while the North Loyalty Basin is the backarc.[2] As the oceanic lithosphere of the Australian Plate was subducting under an oceanic plate in the Northeast, the descending slab metamorphosed to become the Diahot and Pouebo Terranes under high pressure.[2] The moisture released from metamorphism caused partial melting, initiating a series of extrusive volcanism to form the arc of Loyalty Ridge and Islands.[2] The oblique subduction was then jammed by the lighter continental lithosphere of the Norfolk Ridge, which could not sink further into the mantle.[2][44] Instead, the oceanic lithosphere obducted above the Poya Terrane on the Norfolk Ridge, thus bringing the units like the Poya Terrane and the Peridotite Nappe.[2][36]

After obduction, the uplift and exhumation of the metamorphic core complex between Oligocene and Miocene are either simultaneous, or resultant of an extensional event i.e. unloading due to slab detachment.[11] Intrusion of granitoids into the Peridotite Nappe also happened in the Oligocene, possibly due to a short-term reactivated subduction from the New Caledonia Basin.[14] Such hypothesis is synchronized with the proposed relationship between the metamorphic antiform and a renewed compression by such motion.[39]

Re-emergence of New Caledonia after Oligocene

Miocene Nepoui Series witnessed the uplift of Grande Terre at that time, possibly by the forearc bulge in response to the nearby subduction to Vanuatu.[2] After that, it is followed by erosion with deposition happening again, along with the development of fluvial network(s).[2][40] Nowadays, the tropical climate on the Island facilitates heavy erosion, while the coral reef surrounding the islands has started developing only since 0.4 Ma.[2]

Meanwhile, as the New Hebrides Trench is approaching the Loyalty Ridge from the East recently, seismic activities are triggered with potential orogeny in the future.[45]

Geological resources

Thanks to the obduction of the Peridotite Nappe, where its origin is the metal-enriched mantle, metal ores are concentrated as the main earth resources in the region.[2]

Nickel and cobalt

Main article: Nickel mining in New Caledonia
Laterite in the Goro mine.

The nickel and cobalt ore minerals are enriched in laterite, a material deposit at the lower part of the weathering profile of the Peridotite Nappe.[46] The tropical climate provides perfect conditions of its formation through hydrolysis of olivine and pyroxene in the rock.[28] There are three types of the Ni-rich laterite: Fe oxy-hydroxide deposits like goethite, hydrous Mg silicate deposits like Mg-Ni talc, and clay silicate deposits.[7] Among these, only the first type is rich in Co too.[7]

Being the most important earth resource in the territory, the nickel mining industry has contributed to the high local GDP per capita in the past decades.[47] With more than 10 million tonnes of ore reserves, New Caledonia is the fourth largest nickel exporter in the world.[48]

Cobalt mining was also very important, but is no longer in operation since the 1920s.[7] From being first mined in 1876 to 1906, the territory was the monopoly of the cobalt exportation, and the ore was mined in different sites from that of nickel.[7]

Chromium

Chromite distribution in New Caledonia, by USGS (2012).[49]

The mantle-derived Peridotite Nappe also consists of dunite in the harzburgite–lherzolite transition zone.[49] In particular, the rock podiform chromitite bears chromite, which is one of the ore minerals of chromium.[49] Over 3 million tonnes of ore had been mined since the 1880s, but the last mine has been closed in the 1990s.[2][49]

Iron

Sharing the same source as nickel, the iron ore of ferricrete is extensively found on the top of the laterite profiles.[7] It is mined and exported until 1960, when its high impurities of nickel and chromium make the ore unsuitable for the new smelting industry.[7]

Other metals

Gold was extracted in the Fern Hill Mine in the late 19th century, while its occurrence in other places on the island lacks economic importance.[2] Copper, lead and silver were also found in the Diahot Terrane at the same time, with discontinued mining happening in the mid 20th Century.[2][28]

Manganese ore, in the form of small pods, were extracted from the Poya basalts and the altered Peridotite Nappe, from 1918 to 1922 and again from 1949 to 1953.[28]

Sibnite, the antimony-bearing ore mineral found in quartz veins, was also mined shortly between 1883 and 1884.[28]

Platinum group elements are also present on Grande Terre.[7] Osmium, Iridium and ruthenium are enriched in the podiform chromitites from the Peridotite Nappe, but the concentrations are still not high enough for extraction.[7]

Non-metals

There are also some minor non-metal resources. For instance, phosphate was mined on the small Walpole Island of the Loyalty Islands from 1888 to 1914.[50]

Limestone formations, except for those which were formed in the Paleocene, has been mined for local cement industry, as well as for hydrometallurgic Ni industry.[50]

Hydrocarbons are also found onshore and offshore of Grande Terre.[50] Coal in the Formation à Charbon were mined near Moindou on the west coast shortly between 1924 and 1930 and was consumed in the first Ni smelters in Nouméa.[50] Furthermore, there are potentials for petroleum and gas extractions off the West coast of the Grande Terre, which belongs to the Tasman Frontier area of northern Zealandia.[50]

See also

References

  1. ^ Xu, Yang; Liu, Chuan-Zhou (2019-06-01). "Subduction-Induced Fractionated Highly Siderophile Element Patterns in Forearc Mantle". Minerals. 9: 339. doi:10.3390/min9060339.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be bf bg bh bi bj bk bl bm bn bo bp bq br bs bt bu bv bw bx by bz ca cb cc cd ce cf cg ch ci cj ck cl cm cn co cp cq cr cs Cluzel, Dominique; Maurizot, Pierre; Collot, Julien; Sevin, Brice (March 2012). "An outline of the Geology of New Caledonia; from Permian-Mesozoic Southeast Gondwanaland active margin to Cenozoic obduction and supergene evolution". EPISODES. 35: 72-86. doi:10.18814/epiiugs/2012/v35i1/007. Retrieved September 2021. {{cite journal}}: Check date values in: |access-date= (help)
  3. ^ Lillie, A. R.; Brothers, R.N. "The geology of New Caledonia". New Zealand Journal of Geology and Geophysics. 13 (1): 145-183. doi:10.1080/00288306.1970.10428210. Retrieved 2 October 2021. {{cite journal}}: External link in |ref= (help)
  4. ^ a b Wood, Ray; Stagpoole, Vaughan; Wright, Ian; Davy, Bryan; Barnes, Phil (2003). New Zealand's Continental Shelf and UNCLOS Article 76 (PDF). Institute of Geological and Nuclear Sciences Limited. Institute of Geological and Nuclear Sciences series 56. Wellington, New Zealand: National Institute of Water and Atmospheric Research. p. 16. NIWA technical report 123. Archived from the original (PDF) on 21 February 2007. Retrieved 22 February 2007.
  5. ^ "Données Géographiques". Nouvelle-caledonie.gouv.fr (in French). Archived from the original on 30 October 2012. Retrieved 2013-01-30.
  6. ^ a b c d e f g h Garrouste, Romain; Munzinger, Jérôme; Leslie, Andrew; Fisher, Jessica; Folcher, Nicolas; Locatelli, Emma; Foy, Wyndy; Chaillon, Thibault; Cantrill, David J.; Maurizot, Pierre; Cluzel, Dominique; Lowry II, Porter P.; Crane, Peter; Bahain, Jean-Jacques; Voinchet, Pierre; Jourdan, Hervé; Grandcolas, Philippe; André, Nel (15 September 2021). "New fossil discoveries illustrate the diversity of past terrestrial ecosystems in New Caledonia". Scientific Reports. 11. doi:https://doi.org/10.1038/s41598-021-97938-5. Retrieved 3 October 2021. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  7. ^ a b c d e f g h i j k l m Maurizot, Pierre (2011). "First sedimentary record of the pre-obduction convergence in New Caledonia: formation of an Early Eocene accretionary complex in the north of Grande Terre and emplacement of the 'Montagnes Blanches' nappe". Bulletin de la Société Géologique de France. 182 (6): 479-491. Retrieved 1 October 2021.
  8. ^ Geoscience Australia (n.d.). "Fairway Basin and Ridge New Caledonia Basin and Norfolk Ridge". Geoscience Australia. Retrieved 1 November 2021.{{cite web}}: CS1 maint: url-status (link)
  9. ^ a b c d Pearce, J. A.; Lippard, S. J.; Roberts, S. (1 January 1984). "Characteristics and tectonic significance of supra-subduction zone ophiolites". Geological Society, London, Special Publications. 16: 77-94. Retrieved 2 October 2021.
  10. ^ a b Edwards, Sarah J.; Schellart, Wouter P.; Duarte, Joao C. (25 June 2015). "Geodynamic models of continental subduction and obduction of overriding plate forearc oceanic lithosphere on top of continental crust". Tectonics. 34 (7): 1494-1515. doi:https://doi.org/10.1002/2015TC003884. Retrieved 7 October 2021. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  11. ^ a b c d e Patriat, Martin; Collot, Julien; Etienne, Samuel; Poli, Sara; Clerc, Camille; Montmier, Nick; Pattier, France; Juan, Caroline; Roeset, Walter R.; VESPA scientific voyage team (08 March 2018). "New Caledonia Obducted Peridotite Nappe: Offshore Extent and Implications for Obduction and Postobduction Processes". Tectonics. 37 (4): 1077-1096. Retrieved 1 October 2021. {{cite journal}}: Check date values in: |date= (help)
  12. ^ a b Lagabrielle, Yves; Chauvet, Alain; Ulrich, Marc; Guillot, Stéphane (1 November 2013). "Passive obduction and gravity-driven emplacement of large ophiolitic sheets: The New Caledonia ophiolite (SW Pacific) as a case study?". Bulletin de la Société Géologique de France. 184 (6): 545-556. Retrieved 2 October 2021.
  13. ^ a b c Gautier, Pierre; Quesnel, Benoit; Boulvais, Philippe; Cathelineau, Michel (2016). "The emplacement of the Peridotite Nappe of New Caledonia and its bearing on the tectonics of obductio". Tectonics. 35: 3070-3094. doi:10.1002/2016TC004318. Retrieved 7 October 2021.
  14. ^ a b c d e f g h i Cluzel, Dominique; Bosch, Delphine; Paquette, Jean-Louis; Lemennicier, Yves; Montjoie, Philippe; Ménot, René-Pierre (September 2005). "Late Oligocene post-obduction granitoids of New Caledonia: A case for reactivated subduction and slab break-off". Island Arc. 14: 254-271. doi:10.1111/j.1440-1738.2005.00470.x. Retrieved 3 October 2021.
  15. ^ a b Neall, Vincent E; Trewick, Steven A (3 September 2008). "The age and origin of the Pacific islands: a geological overview". PMID 18768382. Retrieved 2 October 2021. {{cite journal}}: Cite journal requires |journal= (help)
  16. ^ Collot, J. Y.; Daniel, J.; Burne, R. V. (1985). "Recent tectonics associated with the subduction/collision of the D'Entrecasteaux zone in the central New Hebrides" (PDF). Tectonophysics. 112 (1): 325–356. Bibcode:1985Tectp.112..325C. doi:10.1016/0040-1951(85)90185-4. Retrieved 7 January 2017.
  17. ^ Calmant, S.; Pelletier, B.; Lebellegard, P.; Bevis, M.; Taylor, F. W.; Phillips, D. A. (2003). "New insights on the tectonics along the New Hebrides subduction zone based on GPS results". J. Geophys. Res. 108 (B6): 2319. Bibcode:2003JGRB..108.2319C. doi:10.1029/2001JB000644.
  18. ^ "M 7.7 - southeast of the Loyalty Islands". USGS. USGS. Retrieved 4 October 2021.
  19. ^ a b Maillet, P.; Monzier, M.; Lefevre, C. (1986). "Petrology of Matthew and Hunter volcanoes, south New Hebrides island arc (southwest Pacific)". J. Volcanol. Geotherm. Res. 30 (1): 1–27. Bibcode:1986JVGR...30....1M. doi:10.1016/0377-0273(86)90065-X.
  20. ^ a b Meffre, Sébastien; Aitchison, Jonathan C.; Crawford, Anthony J. (February 1996). "Geochemical evolution and tectonic significance of boninites and tholeiites from the Koh ophiolite, New Caledonia" (PDF). Tectonics. 15 (1): 67-83. Retrieved 7 October 2021.
  21. ^ a b c d Ali, Jason R.; Aitchison, Jonathan C. (7 June 2001). "Paleomagnetic-tectonic study of the New Caledonia Koh Ophiolite and the mid-Eocene obduction of the Poya Terrane". New Zealand Journal of Geology & Geophysics. 45: 313-322. Retrieved 1 October 2021.
  22. ^ Meffre, S.; Aitchison, J. C.; Crawford, A. J. (January 1996). "Geochemical stratigraphy of boninites and tholeiites from the Permo-Triassic Koh Ophiolite, New Caledonia". Tectonics. 15: 67-83.
  23. ^ Adams, C. J.; Cluzel, D.; Griffin, W.L. (2009). "Detrital zircon ages andprovenance of sedimentary rocks in basement Mesozoic terranes of NewCaledonia". Australian Journal of Earth Sciences. 56: 1023-1047.
  24. ^ a b Campbell, Matthew J.; Shannon, U.; Rosenbaum, G.; Allen, C. M.; Cluzel, D.; Maurizot, P. (April 2008). "Permian rifting and isolation of New Caledonia: Evidence from detritalzircon geochronology". Gondwana Research. 60: 54-68. doi:10.1016/j.gr.2018.04.004. Retrieved 9 October 2021.
  25. ^ a b Cluzel, Dominique; Meffre, Sébastien (2002). "The Boghen Terrane (New Caledonia, SW Pacific): a Jurassic accretionary complex. Preliminary U-Pb radiochronological data on detrital zircon". Comptes Rendus Geoscience. 334 (11): 867-874. doi:https://doi.org/10.1016/S1631-0713(02)01823-0. Retrieved 4 October 2021. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  26. ^ Aitchison, J. C.; Clarke, G. L.; Meffre, S.; Cluzel, D. (January 1995). "G. L." Geology. 23 (2): 161-164. doi:10.1130/0091-7613(1995)023<0161:EACCIN>2.3.CO;2. Retrieved 6 October 2021.
  27. ^ a b c Cluzel, Adams, Meffre, Campbell, Maurizot, Dominique, C. J., Sébastien, Pierre (11 Mar 2020). "Discovery of Early Cretaceous rocks in New Caledonia; new geochemical and U-Pb zircon age constraints on the transition from subduction to marginal breakup in the Southwest Pacific". Journal of Geology, University of Chicago Press. 118 (4): 381-397. Retrieved 31 September, 2021. {{cite journal}}: Check date values in: |access-date= (help)CS1 maint: multiple names: authors list (link)
  28. ^ a b c d e f g h Pirard, Cassian (2007). New Caledonia : Geology and Mining. JogMeg Mineral Ressource Information. p. 58. Retrieved 2 October 2021.
  29. ^ Maurizot, P; Cluzel, D (2014-04). "Pre-obduction records of Eocene foreland basins in central New Caledonia: an appraisal from surface geology and Cadart-1 borehole data". New Zealand Journal of Geology and Geophysics. 57 (3): 300–311. doi:10.1080/00288306.2014.885065. ISSN 0028-8306. {{cite journal}}: Check date values in: |date= (help)
  30. ^ Nicholson, K. N.; Picard, C.; Black, P. M. (15 December 2000). "A comparative study of Late Cretaceous ophiolitic basalts from New Zealand and New Caledonia: implications for the tectonic evolution of the SW Pacific". Tectonophysics. 327 (3–4): 157-171. doi:https://doi.org/10.1016/S0040-1951(00)00167-0. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  31. ^ Secchiari, A.; Montanini, A.; Bosch, D.; Macera, P.; Cluzel, Dominique (2018). "The contrasting geochemical message from the New Caledonia gabbronorites: insights on depletion and contamination processes of the sub-arc mantle in a nascent arc setting". Contributions to Mineralogy and Petrology. 173: 1-26. doi:10.1007/s00410-018-1496-8.
  32. ^ Soret, M.; Agard, P.; Dubacq, B.; Vitale-Brovarone, A.; Monié, P.; Chauvet, A.; Whitechurch, H.; Villemant, B. (December 2015). "Strain localization and fluid infiltration in the mantle wedge during subduction initiation: Evidence from the base of the New Caledonia ophiolite". Lithos. 244. doi:10.1016/j.lithos.2015.11.022.
  33. ^ Pelletier, Bernard (January 2006). "Geology of the New Caledonia region and its implications for the study of the New Caledonian biodiversity". {{cite journal}}: Cite journal requires |journal= (help)
  34. ^ a b Cluzel, Dominique; Meffre, S.; Maurizot, P.; Crawford, A. J. (December 2006). "Earliest Eocene (53 Ma) convergence in the Southwest Pacific: Evidence from pre-obduction dikes in the ophiolite of New Caledonia". Terra Nova. 18 (6): 395-402. doi:10.1111/j.1365-3121.2006.00704.x. Retrieved 7 October 2021.
  35. ^ Eissen, Jean-Philippe; Crawford, Anthony J.; Cotten, Joseph; Meffre, Sébastien; Bellon, Hervé; Delaune, Mireille (30 October 1996). "Geochemistry and tectonic significance of basalts in the Poya Terrane, New Caledonia" (PDF). Tectonophysic. 284: 203-219. Retrieved 2 October 2021.
  36. ^ a b c d Lagabrielle, Yves; Chauvet, Alain; Ulrich, Marc; Guillot, Stephane (November 2013). "Passive obduction and gravity-driven emplacement of large ophiolitic sheets: The New Caledonia ophiolite (SW Pacific) as a case study?". Bulletin de la Societe Geologique de France. 184 (6): 545-556. doi:10.2113/gssgfbull.184.6.545. Retrieved 7 October 2021.
  37. ^ Clarke, G. L.; Aitchison, J. C.; Cluzel, D. (July 1997). "Eclogites and Blueschists of the Pam Peninsula, NE New Caledonia: a Reappraisal". Journal of Petrology. 38 (7): 843-876. doi:https://doi.org/10.1093/petroj/38.7.843. Retrieved 9 October 2021. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  38. ^ Cluzel, Dominique; Whitten, Matthew; Sébastien, Meffre; Aitchison, Jonathan C.; Maurizot, Pierre (9 November 2017). "A Reappraisal of the Poya Terrane (New Caledonia): Accreted Late Cretaceous-Paleocene Marginal Basin Upper Crust, Passive Margin Sediments, and Early Eocene E-MORB Sill Complex". Tectonics. 37 (1): 48-70. Retrieved 2 October 2021.
  39. ^ a b Rawling, Tim; Lister, Gordon (August 2002). "Large-scale structure of the eclogite–blueschist belt of New Caledonia". Journal of Structural Geology. 24 (8): 1239-1258. doi:10.1016/S0191-8141(01)00128-6. {{cite journal}}: |access-date= requires |url= (help)
  40. ^ a b c d Sevin, B.; Maurizot, P.; Cluzel, D.; Tournadour, Elsa; Etienne, S.; Folcher, N.; Jeanpert, J.; Collot, Julien; Iseppi, M.; Meffre, S.; Patriat, Martin (June 2020). "Post-obduction evolution of New Caledonia" (PDF). Geological Society, London, Memoirs. 51 (1): 147-188. Retrieved 2 October 2021.
  41. ^ Babaahmadi, Abbas; Uysal, I. Tonguç; Rosenbaum, Gideon (February 2019). "Late Jurassic intraplate faulting in eastern Australia: A link to subduction in eastern Gondwana and plate tectonic reorganisation". Gondwana Research. 66: 1-12.
  42. ^ Schellart, W. P.; Lister, G. S.; Toy, V. G. (June 2006). "A Late Cretaceous and Cenozoic reconstruction of the Southwest Pacific region: Tectonics controlled by subduction and slab rollback processes". Earth-Science Reviews. 76 (3–4): 191-233. doi:https://doi.org/10.1016/j.earscirev.2006.01.002. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  43. ^ Sutherland, Rupert; Collot, J.; Lafoy, Y.; Logan, G. A.; Hackney, R.; Stagpoole, V.; Uruski, C.; Hashimoto, T. (20 March 2010). "Lithosphere delamination with foundering of lower crust and mantle caused permanent subsidence of New Caledonia Trough and transient uplift of Lord Howe Rise during Eocene and Oligocene initiation of Tonga-Kermadec subduction, western Pacific". Tectonics. 29 (2). doi:https://doi.org/10.1029/2009TC002476. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  44. ^ Cluzel, Dominique; Marion, Iseppi; Chen, Yan (20 July 2021). "Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence". Tectonophysics. 811. doi:https://doi.org/10.1016/j.tecto.2021.228875. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  45. ^ Schellart, W. P.; Lister, G. S.; M. W., Jessell (January 2002). "Analogue modelling of asymmetrical back-arc extension". Journal of the Virtual Explorer. 7: 25-42. doi:10.3809/jvirtex.2002.00046. Retrieved 9 October 2021.
  46. ^ Maurizot, P.; Sevin, B.; Lesimple, S.; Bailly, L.; Iseppi, M.; Robineau, B. (16 June 2020). "Chapter 10 Mineral resources and prospectivity of the ultramafic rocks of New Caledonia". Geological Society, London, Memoirs. 51: 247-277.
  47. ^ Bautzmann, Alexis (May 2021). Mapping the World Atlas géopolitique Mondial Vol.3. Earth View. pp. 36–37. ISBN 978-986-384-482-2.
  48. ^ Sarrailh, Jean Michel; Ayrault, Nathalie (January 2001). "Rehabilitation of nickel mining sites in New Caledonia". Unasylva. 52. Food and Agriculture Organization of the United Nations: 16–20. Retrieved 24 April 2021.
  49. ^ a b c d Mosier, Dan; Singer, Donald; Moring, Barry; Galloway, John (2012). "Podiform Chromite Deposits—Database and Grade and Tonnage Models" (PDF). U.S. Department of the Interior U.S. Geological Survey.
  50. ^ a b c d e Maurizot, P.; Sevin, B.; Lesimple, J.; Jeanpert, J.; Bailly, L.; Robineau, B.; Patriat, M.; Etienne, S.; Monnin, C. (16 June 2020). "Chapter 9 Mineral resources and prospectivity of non-ultramafic rocks of New Caledonia". Geological Society, London, Memoirs. 51: 215-245.
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