The Mackenzie Large Igneous Province (MLIP) is a major
Mesoproterozoic
The Mesoproterozoic Era is a geologic era that occurred from . The Mesoproterozoic was the first era of Earth's history for which a fairly definitive geological record survives. Continents existed during the preceding era (the Paleoproterozoic), ...
large igneous province
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation ...
of the southwestern, western and northwestern
Canadian Shield
The Canadian Shield (french: Bouclier canadien ), also called the Laurentian Plateau, is a geologic shield, a large area of exposed Precambrian igneous and high-grade metamorphic rocks. It forms the North American Craton (or Laurentia), the anc ...
in
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
. It consists of a group of related
igneous rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others being Sedimentary rock, sedimentary and metamorphic rock, metamorphic. Igneous rock ...
s that were formed during a massive igneous event starting about 1,270 million years ago. The large igneous province extends from the
Arctic
The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...
in
Nunavut
Nunavut ( , ; iu, ᓄᓇᕗᑦ , ; ) is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' ...
to near the
Great Lakes
The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lakes ...
in
Northwestern Ontario
Northwestern Ontario is a secondary region of Northern Ontario in the Canadian province of Ontario which lies north and west of Lake Superior and west of Hudson Bay and James Bay. It includes most of subarctic Ontario. Its western boundary is the ...
where it meets with the smaller
Matachewan dike swarm
The Matachewan dike swarm is a large 2,500 to 2,450 million year old Paleoproterozoic dike swarm of Northern Ontario, Canada. It consists of basaltic dikes that were intruded in greenschist, granite-greenstone, and metamorphosed sedimentary terra ...
. Included in the Mackenzie Large Igneous Province are the large
Muskox layered intrusion, the
Coppermine River flood basalt sequence and the massive northwesterly trending
Mackenzie dike swarm
The Mackenzie dike swarm, also called the Mackenzie dikes, forms a large igneous province in the western Canadian Shield of Canada. It is part of the larger Mackenzie Large Igneous Province and is one of more than three dozen dike swarms in va ...
.
As a large igneous province, it is an extremely large area of related igneous rocks that were emplaced over an extremely short
geological time
The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronol ...
span. The igneous rocks comprising the Mackenzie Large Igneous Province originated from processes not associated with normal
plate tectonics
Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large ...
and
seafloor spreading
Seafloor spreading or Seafloor spread is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.
History of study
Earlier theories by Alfred Wegener an ...
. It is one of the several large igneous provinces scattered throughout the Canadian landscape, which can be thousands of kilometres in volume and area. The Mackenzie Large Igneous Province is one of the world's largest
Proterozoic
The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided ...
magma
Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural sa ...
tic provinces, as well as one of the most well-preserved continental flood basalt
terrain
Terrain or relief (also topographical relief) involves the vertical and horizontal dimensions of land surface. The term bathymetry is used to describe underwater relief, while hypsometry studies terrain relative to sea level. The Latin word ...
s on Earth.
Igneous rocks of the Mackenzie Large Igneous Province are generally
mafic
A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...
in composition, including
basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...
and
gabbro
Gabbro () is a phaneritic (coarse-grained), mafic intrusive igneous rock formed from the slow cooling of magnesium-rich and iron-rich magma into a holocrystalline mass deep beneath the Earth's surface. Slow-cooling, coarse-grained gabbro is che ...
.
Even though the Mackenzie Large Igneous Province is classified as a large igneous province like other extremely large accumulations of igneous rocks on Earth, it is much larger than large igneous province standards. The standard size classification for large igneous provinces is a minimum areal extent of . However, the Mackenzie dike swarm itself occupies an area of at least , making the Mackenzie Large Igneous Province larger than the
Ontong Java Plateau
The Ontong Java Plateau (OJP) is a massive oceanic plateau located in the southwestern Pacific Ocean, north of the Solomon Islands.
The OJP was formed around (Ma) with a much smaller volcanic event around 90 Ma. Two other southwestern Pacific ...
(in the southwestern
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
) and the
U.S. state
In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sover ...
of
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...
.
Geology
Origins
Like most large igneous provinces, the Mackenzie Large Igneous Province has its origins in a
mantle plume
A mantle plume is a proposed mechanism of convection within the Earth's mantle, hypothesized to explain anomalous volcanism. Because the plume head partially melts on reaching shallow depths, a plume is often invoked as the cause of volcanic hot ...
—an upwelling zone of abnormally hot rock within the Earth's
mantle. As the head of the Mackenzie plume encountered the Earth's
lithosphere
A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust (geology), crust and the portion of the upper mantle (geology), mantle that behaves elastically on time sca ...
, it spread out and melted catastrophically to form large volumes of basaltic magma. This resulted in the creation of a stationary volcanic zone west of
Victoria Island
Victoria Island ( ikt, Kitlineq, italic=yes) is a large island in the Arctic Archipelago that straddles the boundary between Nunavut and the Northwest Territories of Canada. It is the List of islands by area, eighth-largest island in the world, ...
that experienced considerable volcanism known as the
Mackenzie hotspot
The Mackenzie hotspot was a volcanic hotspot that existed about 1.3 billion years ago across Canada from the Northwest Territories and Nunavut. It was centred on what is now Darnley Bay on southwestern Victoria Island.
Extent
The Mackenzie ho ...
. Evidence for the Mackenzie hotspot include the existence of the giant mafic Mackenzie dike swarm because of its fanning pattern adjacent to the Muskox intrusion.
The size of the Mackenzie hotspot is considered to have been about in diameter.
This calculation is based on the analysis of magmatic fabric in the Mackenzie dike swarm, which shows that magma flow was only vertical close to the middle of the Mackenzie plume and only subhorizontal away from the plume.
However, if subhorizontal flow is a result of dike ascent to a level of impartial lightness in the Earth's crust, it would not be related to the size of the Mackenzie plume.
Instead, the analysis of dike swarm geometry could possibly maintain evidence for the smallest diameter of the Mackenzie plume.
The outer limit separating the zone of fanning dike geometry and subparallel dikes might be suggestive of the smallest diameter for the Mackenzie plume because it is not probable that the stress related to a magmatic zone has consequence over a region that is lesser than the Mackenzie plume, which created the feature.
From this analysis, the smallest diameter of the Mackenzie plume would have been about .
Uranium-lead dating of certain Mackenzie dikes from an array of distances from an assigned focal point give an age of million years.
This indicates that the Mackenzie hotspot essentially emplaced the Mackenzie Large Igneous Province as a whole throughout the associated landscape.
The associated Mackenzie plume is consistent with mantle plumes that have deep origins within the Earth's mantle.
The Mackenzie hotspot is interpreted to have been similar to the early volcanism of the
Yellowstone hotspot
The Yellowstone hotspot is a volcanic hotspot in the United States responsible for large scale volcanism in Idaho, Montana, Nevada, Oregon, and Wyoming, formed as the North American tectonic plate moved over it. It formed the eastern Snake Ri ...
.
Both hotspots produced massive qualities of basaltic lava flows that were identical with the formation of dike swarms during a short period of time at the beginning of mantle plume volcanism.
It is estimated that the majority of volcanism that formed the Mackenzie Large Igneous Province took place for no more than two million years, and subsequent volcanism is unknown.
However, the younger and smaller
Franklin Large Igneous Province
The Franklin Large Igneous Province is a Neoproterozoic large igneous province in the Canadian Arctic of Northern Canada. It represents one of the largest large igneous provinces in Canada, consisting of the Natkusiak flood basalts on Victoria I ...
just to the northeast is considered to have been formed by a similar mantle plume between 727 and 721 million years ago.
The short time span of two million years for magma emplacement in the Mackenzie Large Igneous Province is also present for the Yellowstone hotspot.
Extensional forces
![MLIP igneous figures](https://upload.wikimedia.org/wikipedia/commons/c/cb/MLIP_igneous_figures.png)
At the beginning of the Mackenzie magmatic event, the Mackenzie hotspot collided with lithosphere that was already in an extensional regime that allowed rifting to occur.
Passive rifting has been interpreted as the mechanism that produced the opening of the former
Poseidon Ocean, the geometry of which would have been partly controlled by dike swarm geometry.
Fahrig (1987) proposed that the Mackenzie plume impact resulted in the emplacement of a
triple junction
A triple junction is the point where the boundaries of three tectonic plates meet. At the triple junction each of the three boundaries will be one of three types – a ridge (R), trench (T) or transform fault (F) – and triple junctions can b ...
that had a large mafic dike swarm on every rift arm.
Two of the first arms formed the Poseidon Ocean basin and the third arm failed thus forming an
aulacogen
An aulacogen is a failed arm of a triple junction. Aulacogens are a part of plate tectonics where oceanic and continental crust is continuously being created, destroyed, and rearranged on the Earth’s surface. Specifically, aulacogens are a rift ...
.
This tectonic setting suggestion can be comparable with the early volcano-tectonic evolution of the Yellowstone hotspot, which developed two arms instead of three, followed by failure of both arms.
At the Mackenzie hotspot, rifting is considered to have been passive and to have taken place in the crust above the hotspot that should have been weakened by the Mackenzie plume.
Crustal uplift may have also provided stresses contributing to rifting.
A slightly younger but possibly related geologic feature is the long
Midcontinent Rift System
The Midcontinent Rift System (MRS) or Keweenawan Rift is a long geological rift in the center of the North American continent and south-central part of the North American plate. It formed when the continent's core, the North American craton, be ...
adjacent to the southern end of the Mackenzie Large Igneous Province.
The
Lake Superior
Lake Superior in central North America is the largest freshwater lake in the world by surface areaThe Caspian Sea is the largest lake, but is saline, not freshwater. and the third-largest by volume, holding 10% of the world's surface fresh wa ...
portion of the Midcontinent Rift System is bounded on the south by pre-existing continental faults that had substantial right-lateral movement before the formation of the Midcontinent Rift System.
This period of rifting was a large event for
copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
mineralization, and the rifting event later deceased when the
Grenville orogeny
The Grenville orogeny was a long-lived Mesoproterozoic mountain-building event associated with the assembly of the supercontinent Rodinia. Its record is a prominent orogenic belt which spans a significant portion of the North American continent, ...
collision occurred.
Magmatic history
The massive extent of the Mackenzie Large Igneous Province contains a number of magmatic features that were formed during the extensive Mackenzie magmatic event. This includes
flood basalt
A flood basalt (or plateau basalt) is the result of a giant volcanic eruption or series of eruptions that covers large stretches of land or the ocean floor with basalt lava. Many flood basalts have been attributed to the onset of a hotspot reach ...
s,
layered intrusion
A layered intrusion is a large sill-like body of igneous rock which exhibits vertical layering or differences in composition and texture. These intrusions can be many kilometres in area covering from around to over and several hundred metres to ...
s,
sills and
dikes
Dyke (UK) or dike (US) may refer to:
General uses
* Dyke (slang), a slang word meaning "lesbian"
* Dike (geology), a subvertical sheet-like intrusion of magma or sediment
* Dike (mythology), ''Dikē'', the Greek goddess of moral justice
* Dikes, ...
, which are widespread throughout the large igneous province. With an area of , the Mackenzie event is the largest magmatic event ever to occur on the Canadian landscape. At least two magmatic formations can be considered large igneous provinces in their own advantage, both of which cover an area of more than .
Placement of the Muskox intrusion
![Muskox intrusion and groups](https://upload.wikimedia.org/wikipedia/commons/6/6d/Muskox_intrusion_and_groups.png)
Adjacent to McGregor Lake in western
Nunavut
Nunavut ( , ; iu, ᓄᓇᕗᑦ , ; ) is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' ...
lies the massive Muskox intrusion. It remains as one of the largest and most studied
layered intrusion
A layered intrusion is a large sill-like body of igneous rock which exhibits vertical layering or differences in composition and texture. These intrusions can be many kilometres in area covering from around to over and several hundred metres to ...
s on Earth, as well as one of the most valuable from an economic perspective. The intrusion represents the oldest igneous formation of the Mackenzie magmatic event, having formed between 1,905 and 1,155 million years ago. It maintains a triangular trough-shaped
magma chamber
A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces buoyant forces on the magma that tend to drive it upw ...
that extends below the surface.
With a width of and a length of over , the Muskox intrusion is overlain by a sequence of Coppermine flood basalts that remains thick.
The Muskox intrusion can be separated into three sections, including an olivine gabbro feeder dike to the intrusion, another contact margin zone, and an upper layered series.
Because of different levels of erosion and outcroppings of the Muskox intrusion at higher structural levels, north of the
Coppermine River
The Coppermine River is a river in the North Slave and Kitikmeot regions of the Northwest Territories and Nunavut in Canada. It is long. It rises in Lac de Gras, a small lake near Great Slave Lake, and flows generally north to Coronation Gulf, a ...
the overlying margin zone and layered series covers the feeder dike section.
The layering series dips gently north as do the overlying Coppermine flood basalts.
Weathering of the Muskox dipping sequence has exposed a cross-section through the entire dipping sequence, starting with the Coppermine flood basalts in the north above the roof of the magma chamber, down through the igneous layering of the Muskox intrusion and into the keel region of the intrusion and its intersection with the olivine gabbro feeder dike that forms the southernmost sector.
The margin zone characterizes the western and eastern outer limits of the intrusion.
Construction of the Mackenzie dike swarm
Widespread throughout the Mackenzie Large Igneous Province is the Mackenzie dike swarm. This extensive group of radially oriented dikes is more than wide and long, extending from Northwestern Ontario through northern
Manitoba
Manitoba ( ) is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population o ...
and northern
Saskatchewan
Saskatchewan ( ; ) is a Provinces and territories of Canada, province in Western Canada, western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on t ...
to Nunavut and the
Northwest Territories
The Northwest Territories (abbreviated ''NT'' or ''NWT''; french: Territoires du Nord-Ouest, formerly ''North-Western Territory'' and ''North-West Territories'' and namely shortened as ''Northwest Territory'') is a federal territory of Canada. ...
. The Mackenzie dike swarm was emplaced into older metamorphic and igneous rocks of the Canadian Shield about 1,200 million years ago. Individual dikes of the Mackenzie swarm are respectively to long and thick.
This indicates that the Mackenzie dikes are larger than those associated with the
Columbia River Basalt Group
The Columbia River Basalt Group is the youngest, smallest and one of the best-preserved continental flood basalt province on Earth, covering over mainly eastern Oregon and Washington, western Idaho, and part of northern Nevada. The basalt grou ...
in the United States, which are respectively to long and to thick.
The size differentiation of the Columbia River and Mackenzie dikes suggests that the crude estimates for both dike length and thickness ratio are within the ranges for the Mackenzie hotspot and for the early stage of the Yellowstone hotspot.
![Mackenzie dike swarm](https://upload.wikimedia.org/wikipedia/commons/4/43/Mackenzie_dike_swarm.png)
The Mackenzie dike swarm is the largest dike swarm known on Earth and is one of the several dike swarms found throughout the Canadian Shield.
Mafic dikes cut
Archean
The Archean Eon ( , also spelled Archaean or Archæan) is the second of four geologic eons of Earth's history, representing the time from . The Archean was preceded by the Hadean Eon and followed by the Proterozoic.
The Earth
Earth ...
and
Proterozoic
The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided ...
rocks of the Canadian Shield, including those in the
Athabasca Basin
The Athabasca Basin is a region in the Canadian Shield of northern Saskatchewan and Alberta, Canada. It is best known as the world's leading source of high-grade uranium and currently supplies about 20% of the world's uranium.
The basin i ...
in Saskatchewan, the Thelon Basin in Nunavut and the Baker Lake Basin in the Northwest Territories.
The mafic dikes display evidence that the unmetamorphosed
basin-fill sequence was deposited before the Mackenzie dikes were intruded into the associated basins.
When the giant Mackenzie dike swarm intruded into the Canadian Shield, it partly uplifted and intruded the
Slave craton
The Slave Craton is an Archaean craton in the north-western Canadian Shield, in Northwest Territories and Nunavut. The Slave Craton includes the 4.03 Ga-old Acasta Gneiss which is one of the oldest dated rocks on Earth.
Covering about , ...
in the Northwest Territories and Nunavut.
This was the last major event to affect the core of the Slave craton, although later on some younger mafic magmatism registered along its boundaries.
This includes the magmatic events that formed the 723 million year old Franklin Large Igneous Province and the 780 million year old Hottah gabbro sheets.
Since the Mackenzie dike swarm intruded the Slave craton, the craton has been repeatedly submerged under seas.
In northern
Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
, the 1,265 to 1,269 million year old
Bear River dikes The Bear River dikes are a 1,265 to 1,269 million year old group of dikes in northern Yukon, Canada. They represent a feature related to magmatism of the extensive Mackenzie Large Igneous Province and are considered to be the western exten ...
are interpreted to represent the western extension of the Mackenzie dike swarm.
They display geologic similarities with the Mackenzie dike swarm and the Coppermine River flood basalts, and are therefore regarded as products of the Mackenzie plume.
The dikes intrude through Early Proterozoic sedimentary
strata
In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as ei ...
of the Wernecke Supergroup, some of which exist as separate intrusions while others occur in swarms of up to eight dikes.
Individual dikes range from to thick and up to long.
Medium to fine grained
diorite
Diorite ( ) is an intrusive igneous rock formed by the slow cooling underground of magma (molten rock) that has a moderate content of silica and a relatively low content of alkali metals. It is intermediate in composition between low-silic ...
and gabbro comprise the Bear River dikes and are occasionally altered by metamorphism to form
greenschist
Greenschists are metamorphic rocks that formed under the lowest temperatures and pressures usually produced by regional metamorphism, typically and 2–10 kilobars (). Greenschists commonly have an abundance of green minerals such as chlorite ...
.
Apart from two dikes that display differentiation, such as containing weak penetrative
foliation
In mathematics (differential geometry), a foliation is an equivalence relation on an ''n''-manifold, the equivalence classes being connected, injectively immersed submanifolds, all of the same dimension ''p'', modeled on the decomposition of ...
of unknown age and origin and being cross-cut by undated
hematitic veins, the Bear River dikes are interpreted to have formed during a single magmatic phase.
Flood basalts
Between 1,200 and 740 million years ago, a series of flood basalt eruptions took place. At the northern portion of the Mackenzie Large Igneous Province, vast volumes of basaltic lava paved over a large area of the northwestern Canadian Shield. This extensive volcanism constructed a large
lava plateau
A volcanic plateau is a plateau produced by volcanism, volcanic activity. There are two main types: lava plateaus and pyroclastic plateaus.
Lava plateau
Lava plateaus are formed by highly fluid basaltic lava during numerous successive erup ...
with an area of , representing a volume of lavas of at least .
This extensive area of flood basalt lava flows has been termed the Coppermine River flood basalts hence given the location of the flood basalt sequence. With an area of and a volume of , the Coppermine River flood basalt sequence is larger than the Columbia River Basalt Group in the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
and comparable in size to the
Deccan Traps
The Deccan Traps is a large igneous province of west-central India (17–24°N, 73–74°E). It is one of the largest volcanic features on Earth, taking the form of a large shield volcano. It consists of numerous layers of solidified flood ...
in west-central
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
. This makes the Coppermine River flood basalts one of the largest flood basalt events ever to appear on the North American continent, as well as on Earth. The maximum thickness of the Coppermine River flood basalts is and consist of 150 lava flows, each to thick.
The Coppermine River flood basalts were extruded shortly after a period of crustal uplift that later resulted in a short period of collapse in the associated landscape.
This sudden uplift was likely caused by rising magma of the Mackenzie plume, which later resulted in the appearance of the Mackenzie hotspot. The early Muskox intrusion is considered to have originally been a sill-shaped magma reservoir for the overlying Coppermine River flood basalts during their formation.
With the Coppermine River basalts comprising more than 100 individual lava flows, the potential volumes of
silicate
In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is al ...
magma that moved through the Muskox conduit were in the order of .
Further to the northeast, the
Nauyat Formation
The Nauyat Formation is a Neoproterozoic-Mesoproterozoic geologic formation located on northwestern Baffin Island, Nunavut, Canada. It consists of a series of continental flood basalt lava flows of the Mackenzie Large Igneous Province with a th ...
flood basalts on northwestern
Baffin Island
Baffin Island (formerly Baffin Land), in the Canadian territory of Nunavut, is the largest island in Canada and the fifth-largest island in the world. Its area is , slightly larger than Spain; its population was 13,039 as of the 2021 Canadia ...
of
Nunavut
Nunavut ( , ; iu, ᓄᓇᕗᑦ , ; ) is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' ...
were erupted on a smaller scale about 900 million years ago. These flood basalts reach a thickness of . Just southeast of the
Queen Maud Gulf
Queen or QUEEN may refer to:
Monarchy
* Queen regnant, a female monarch of a Kingdom
** List of queens regnant
* Queen consort, the wife of a reigning king
* Queen dowager, the widow of a king
* Queen mother, a queen dowager who is the mother ...
, the
Ekalulia Formation flood basalts remain to thick.
They appear green in colour and contain the
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
silicate
In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is al ...
mineral
olivine
The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ...
.
Minor
pillow lava
Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava underwater, or ''subaqueous extrusion''. Pillow lavas in volcanic rock are characterized by thick sequences of disconti ...
s also exist in the Ekalulia flood basalts.
Mineralization
Heavy
platinum group
The platinum-group metals (abbreviated as the PGMs; alternatively, the platinoids, platinides, platidises, platinum group, platinum metals, platinum family or platinum-group elements (PGEs)) are six noble, precious metallic elements clustered to ...
elements and copper mineralization exists in the basal margin of the Muskox intrusion.
Research operated by Muskox Minerals Corp. proclaims that this extensive layered intrusion has the possibility to evolve into a massive expected source of copper,
nickel
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to ...
and platinum group metals.
The expected mineralization potential for the Muskox intrusion is supported as a result of its strong similarities to the Noril'sk-Talnakh intrusions in Siberia where the richest
ore
Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 April 2 ...
bodies exist on Earth.
Because the Muskox intrusion has strong similarities to the Noril'sk-Talnakh area in Siberia, a number of mineral explorations have taken place. The first mineral exploration of the Muskox intrusion occurred during the 1950s when surface prospecting began by the International Nickel Company of Canada, which is now known as
Vale Inco
Vale Canada Limited (formerly Vale Inco, CVRD Inco and Inco Limited; for corporate branding purposes simply known as "Vale" and pronounced in English) is a wholly owned subsidiary of the Brazilian mining company Vale. Vale's nickel mining and ...
.
In the 1980s, many small companies with little financing and fragmented claim blocks attended sampling and a number of drilling operations on outcroppings of the Muskox intrusion that contained platinum group elements.
Exposed portions of the feeder dike south of the Coppermine River comprise bodies of large semi-massive and disseminated copper-nickel sulfides rich in platinum group metals.
At the margins of the Muskox intrusion, sulfide bearing zones more than long contain
palladium
Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself na ...
, platinum,
gold
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile met ...
, copper and nickel.
This is the location where casual mineral exploration companies searched the Muskox intrusion in the past.
See also
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Timeline of volcanism on Earth
This timeline of volcanism on Earth includes a list of major volcanic eruptions of approximately at least magnitude 6 on the Volcanic explosivity index (VEI) or equivalent sulfur dioxide emission during the Quaternary period (from 2.58 Mya to th ...
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Volcanology of Canada
Volcanic activity is a major part of the geology of Canada and is characterized by many types of volcanic landform, including lava flows, volcanic plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcanoes, calder ...
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Volcanology of Eastern Canada
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Volcanology of Northern Canada
Volcanism of Northern Canada has produced hundreds of volcanic areas and extensive lava formations across Northern Canada. The region's different volcano and lava types originate from different tectonic settings and types of volcanic eruptions, ra ...
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Volcanology of Western Canada
Volcanism of Western Canada has produced lava flows, lava plateaus
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be eru ...
References
{{Large igneous provinces
Plate tectonics
Mesoproterozoic volcanism
Hotspot volcanism
Rift volcanism
Historical geology
Economic geology