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128-743: Part of the Canadian Shield, the TGB contains some of the oldest known rocks on Earth. The belt is made up of a number of geologic features such as batholiths , stocks , dikes , volcanic complexes , layered intrusions and deformation zones. These are situated in several geographical townships in the municipality of Temagami, including Chambers , Strathy , Strathcona , Briggs and possibly Best . Geologists assume that greenstone belts were formed by many geological processes, such as tectonism , magmatism , metamorphism and sedimentation . They are important economically for large metal deposits, and for

256-483: A 755 m (2,477 ft) mine shaft . For the first few years after the mine opened, ore trucks were barged down the northeastern arm of Lake Temagami to the town of Temagami, but this soon proved to be too expensive. The result was to create a gravel road from Highway 11 to the eastcentral shore of Lake Temagami. This road, now known as the Lake Temagami Access Road , was completed in 1958 and

384-612: A face-centered cubic lattice and iron cations occupying interstitial sites . Half of the Fe cations occupy tetrahedral sites while the other half, along with Fe cations, occupy octahedral sites. The unit cell consists of thirty-two   O ions and unit cell length is a = 0.839 nm. As a member of the inverse spinel group, magnetite can form solid solutions with similarly structured minerals, including ulvospinel ( Fe 2 TiO 4 ) and magnesioferrite ( MgFe 2 O 4 ). Titanomagnetite, also known as titaniferous magnetite,

512-601: A prehistoric volcano , existed west of Link Lake. Also, coarsest felsic volcanic fragments occur in feldspar-phyric pyroclastic deposits exposed on the Sherman Mine property, suggesting the approximate location of a volcanic vent. Just north of the Milne Townsite lies a minor felsic volcanic vent exposed along the Milne-Sherman Road. A quartz porphyry has intruded mafic and rhyolitic lava flows and

640-591: A 4 km (2.5 mi) length of the deformation zone. The gold deposits are found in many rock types, indicating a stronger gold-bearing system with the potential of larger gold deposits. A number of gold-pyrite deposits exist in felsic volcanic rocks overlying the Older Volcanic Complex, near and on the northwestern part of the Net Lake-Vermilion Lake Deformation Zone. These deposits were likely formed during

768-421: A billion years. Extending from Net Lake to Vermilion Lake lies a northeast–southwest trending high strain zone known as the Net Lake-Vermilion Lake Deformation Zone. Because geologic mapping has not been done comprehensively throughout this zone, its exact width is unknown. The expression of this deformation zone is clearly identifiable by the intense change in volcanic rocks of the TGB. Volcanic units comprising

896-555: A black streak . Small grains of magnetite are very common in igneous and metamorphic rocks . The chemical IUPAC name is iron(II,III) oxide and the common chemical name is ferrous-ferric oxide . In addition to igneous rocks, magnetite also occurs in sedimentary rocks , including banded iron formations and in lake and marine sediments as both detrital grains and as magnetofossils . Magnetite nanoparticles are also thought to form in soils, where they probably oxidize rapidly to maghemite . The chemical composition of magnetite

1024-571: A compass in Tasmania to keep navigation problems to the minimum. Magnetite crystals with a cubic habit are rare but have been found at Balmat, St. Lawrence County, New York , and at Långban, Sweden . This habit may be a result of crystallization in the presence of cations such as zinc. Magnetite can also be found in fossils due to biomineralization and are referred to as magnetofossils . There are also instances of magnetite with origins in space coming from meteorites . Biomagnetism

1152-645: A complex series of chlorite trondhjemite , hornblende quartz diorite and hornblende trondhjemite magmas that were emplaced during more than one magmatic event. The trend of metamorphosed volcanic rocks in Briggs and Strathcona townships is parallel to the intrusion contact. A planar fabric , attributed to the earliest deformation of the TGB, exists in the outer margin of the intrusion. Intrusive dikes composed of quartz and feldspar-quartz porphyry are widespread in Strathy Township. All dike types were placed in

1280-463: A component of protein plaques in the brain. Such plaques have been linked to Alzheimer's disease . Increased iron levels, specifically magnetic iron, have been found in portions of the brain in Alzheimer's patients. Monitoring changes in iron concentrations may make it possible to detect the loss of neurons and the development of neurodegenerative diseases prior to the onset of symptoms due to

1408-536: A crystal structure phase transition from a monoclinic structure to a cubic structure known as the Verwey transition . Optical studies show that this metal to insulator transition is sharp and occurs around 120   K. The Verwey transition is dependent on grain size, domain state, pressure, and the iron-oxygen stoichiometry . An isotropic point also occurs near the Verwey transition around 130   K, at which point

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1536-413: A dike of diorite. In the middle of the intrusive body, the grain size of quartz phenocrysts averages roughly 3 mm (0.12 in) , but become smaller towards the edge of the intrusion. Broken fragmental rocks, interpreted to be carapace breccia, are exposed along the western margin of the intrusion. Exposed near a minor felsic lava dome is a fine grained, quartz-phyric felsic rock that may represent

1664-708: A felsic volcanic vent at the western end of Link Lake. Many dark green, highly vesicular, iron-rich tholeiitic basalts occur in the Turtle Lake Formation, and are interbedded with thin-bedded wackes on the southern limb of the Tetapaga Syncline. The basalts are best exposed along the south shore of Turtle Lake. In some cases, the basalt vesicles are over 1 cm (0.39 in) in diameter and are now filled by white quartz. A series of dark green, massive and pillowed iron-rich tholeiitic basalt lava flows compose an unnamed upper volcanic formation of

1792-565: A heterolithic, volcaniclastic, matrix -supported conglomerate unit that overlies felsic lava flows and pillowed, calc-alkaline basalts of the Link Lake Formation. Many rounded to subangular felsic and mafic volcanic fragments are known to occur in the unit, as well as rare quartz vein fragments and one fragment of white chert. The conglomerate unit passes laterally and vertically into thin bedded deposits. These thin bedded deposits are interpreted to be turbidites that originated from

1920-430: A highly porous high-surface-area material, which enhances its effectiveness as a catalyst. Magnetite micro- and nanoparticles are used in a variety of applications, from biomedical to environmental. One use is in water purification: in high gradient magnetic separation, magnetite nanoparticles introduced into contaminated water will bind to the suspended particles (solids, bacteria, or plankton, for example) and settle to

2048-431: A human health hazard, airborne magnetite is a result of pollution (specifically combustion). These nanoparticles can travel to the brain via the olfactory nerve, increasing the concentration of magnetite in the brain. In some brain samples, the nanoparticle pollution outnumbers the natural particles by as much as 100:1, and such pollution-borne magnetite particles may be linked to abnormal neural deterioration. In one study,

2176-583: A large portion of northwestern Strathy Township and is penetrated by mafic intrusions, although the Kanichee Intrusion consists of peridotite and pyroxenite, which are ultramafic rocks. Just to the southeast, the Younger Volcanic Complex consists mainly of mafic volcanic rocks that form four geologic formations . The Arsenic Lake Formation is composed of dark green, iron-rich, massive and pillowed tholeiitic basalts . Throughout

2304-413: A larger area of weakness that was tectonically active over the past billion years. Evidence for early tectonism , likely related to volcanic activity, include the greater density of felsic dikes concentrated immediately around these zones. An example is the north–south trending Big Dan Shear Zone situated near the former garbage dump of Temagami. The felsic dikes near this zone are interpreted to represent

2432-408: A mafic sill in northwest Strathy Township. Within these high-strain zones quartz veins normally contain chalcopyrite, pyrite, pyrrhotite with exsolved pentlandite and traces of sphalerite and galena. Chalcopyrite, pyrrhotite and pentlandite are deposited throughout shear zones which lack quartz veining. These zones are not known to contain large amounts of gold, although investigations are incomplete. It

2560-532: A now abandoned gold mine 3 km (1.9 mi) north of the Temagami, in the early 1900s with the construction of a 17 m (56 ft) mine shaft with 27.3 m (90 ft) of underground workings. In 1909 about 270 tons of ore was shipped out of the shaft. A 160.1 m (525 ft) mine shaft with five levels was constructed during a second period of exploration from 1930 to 1948. About 1,524 m (5,000 ft) of drifting and crosscutting

2688-867: A quartz vein network, enveloped by alteration in tholeiitic basalts, paralleling the Net Lake-Vermilion Lake Deformation Zone. About 1 km (0.62 mi) north of Beanland lies the abandoned Hermiston-McCauley Mine , situated on the northwestern side of the Net Lake-Vermilion Lake Deformation Zone. From 1935 to 1940, a 115.1 m (378 ft) three-compartment mine shaft was constructed. Three levels were created, two of which had 1,853.1 m (6,080 ft) of lateral work. Reserves have been variously estimated at 31,000 tons averaging 0.275 oz (7.8 g) of gold per ton, 45,700 tons averaging 0.30 oz (8.5 g) of gold per ton over 1 m (3.3 ft) , or 9,000 tons averaging 0.5 oz (14 g) of gold per ton over 0.91 m (3.0 ft) . A main and subsidiary quartz-rich zone occur in

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2816-545: A rhyolite lava flow. An igneous body, interpreted to be a subvolcanic intrusion, is exposed approximately 1 km (0.62 mi) to the northwest and might have formed during the same magmatic event as the felsic dome. Exposed along the Sherman Mine railroad west of the former Milne sawmill lumber yard is a porphyritic body composed of quartz-feldspar. It is unknown if this igneous rock is a rhyolitic lava flow or an intrusion. Several north-trending felsic dikes, composed mainly of feldspar and quartz-feldspar, are located north of

2944-409: A ruptured intrusion composed of diorite, which intrudes felsic volcanic rocks in a northwesterly direction with the strike of the Net Lake-Vermilion Lake Deformation Zone. The main vein is at least 76.1 m (250 ft) long and up to 1.5 m (4.9 ft) wide. Pyrite with chalcopyrite and gold occupies the quartz-rich zones as blebs and small veins. Mining operations began at Leckie Mine ,

3072-503: A science important in understanding plate tectonics and as historic data for magnetohydrodynamics and other scientific fields . The relationships between magnetite and other iron oxide minerals such as ilmenite , hematite, and ulvospinel have been much studied; the reactions between these minerals and oxygen influence how and when magnetite preserves a record of the Earth's magnetic field . At low temperatures, magnetite undergoes

3200-742: A section of the property, including the area that was once owned by Strathy Basin Mines. McVeigh conducted geophysical surveys over Strathy Basin's mineralized zone and announced no conductors. From 1974 to 1975 Vale Limited owned an extensive section of the Strathy Township property. They conducted magnetic and electromagnetic surveys, as well as mapping and drilling. Vale announced that they intersected mineralized sulfide zones ranging from 3.1 m (10 ft) to 45.6 m (150 ft) thick. In 1952 Rib Lake Copper Mines explored areas adjacent to Whitney Lake and between Whitney Lake and Rib Lake , by creating trenches and carrying out diamond drilling. Nickel

3328-598: A subvolcanic feeder system to the overlying felsic volcanic rocks. It is probable that the dikes maintained a former zone of weakness now demonstrated by the shear zones. Renewed tectonic activity along the Big Dan Shear Zone is manifested by offset of clastic sediments east of the Ontario Northland Railway . This phase of tectonic activity displaced felsic dikes north of the exposed part of this shear zone. However, considerable displacement of

3456-529: A vast deposit of magnetite-bearing sand dunes in Peru . The dune field covers 250 square kilometers (100 sq mi), with the highest dune at over 2,000 meters (6,560 ft) above the desert floor. The sand contains 10% magnetite. In large enough quantities magnetite can affect compass navigation . In Tasmania there are many areas with highly magnetized rocks that can greatly influence compasses. Extra steps and repeated observations are required when using

3584-416: Is Fe (Fe ) 2 (O ) 4 . This indicates that magnetite contains both ferrous ( divalent ) and ferric ( trivalent ) iron, suggesting crystallization in an environment containing intermediate levels of oxygen. The main details of its structure were established in 1915. It was one of the first crystal structures to be obtained using X-ray diffraction . The structure is inverse spinel , with O ions forming

3712-818: Is a large mass of intrusive igneous rock (also called plutonic rock), larger than 100 km (40 sq mi) in area, that forms from cooled magma deep in the Earth's crust . Batholiths are almost always made mostly of felsic or intermediate rock types, such as granite , quartz monzonite , or diorite (see also granite dome ). Although they may appear uniform, batholiths are in fact structures with complex histories and compositions. They are composed of multiple masses, or plutons , bodies of igneous rock of irregular dimensions (typically at least several kilometers) that can be distinguished from adjacent igneous rock by some combination of criteria including age, composition, texture, or mappable structures. Individual plutons are solidified from magma that traveled toward

3840-517: Is a solid solution between magnetite and ulvospinel that crystallizes in many mafic igneous rocks. Titanomagnetite may undergo oxy-exsolution during cooling, resulting in ingrowths of magnetite and ilmenite. Natural and synthetic magnetite occurs most commonly as octahedral crystals bounded by {111} planes and as rhombic-dodecahedra . Twinning occurs on the {111} plane. Hydrothermal synthesis usually produces single octahedral crystals which can be as large as 10 mm (0.39 in) across. In

3968-493: Is about 60 m (200 ft) long. Layered chert-magnetite and lesser chert-pyrite-pyrrhotite iron formations are located at the base of the Arsenic Lake Formation. Former drilling near Vermilion Lake and spatial relationships observed on the surface, suggest that the sulfide-rich iron formation lies up to 10 m (33 ft) stratigraphically under the oxide facies iron formation. Iron production from

Temagami Greenstone Belt - Misplaced Pages Continue

4096-703: Is also a chemical basis for cellular sensitivity to electric and magnetic fields ( galvanotaxis ). Pure magnetite particles are biomineralized in magnetosomes , which are produced by several species of magnetotactic bacteria . Magnetosomes consist of long chains of oriented magnetite particle that are used by bacteria for navigation. After the death of these bacteria, the magnetite particles in magnetosomes may be preserved in sediments as magnetofossils. Some types of anaerobic bacteria that are not magnetotactic can also create magnetite in oxygen free sediments by reducing amorphic ferric oxide to magnetite. Several species of birds are known to incorporate magnetite crystals in

4224-482: Is also manifest as 1 m (3.3 ft) wide veins that have been traced along strike for more than 100 m (330 ft) . Basalt has been replaced by calcite in a restricted area just north of the Temagami's former garbage dump. Although developed adjacent to the Link Lake Shear Zone, rocks within and just outside the calcite alteration zone do not normally contain significant foliation. Thus, if

4352-501: Is also unknown if platinum group metals (which include platinum , palladium , rhodium , iridium , osmium and ruthenium ) exist in these zones because no searches for platinum group elements have been undertaken. Gold and copper values occupy a northeast-trending iron formation within the Net Lake-Vermilion Lake Deformation Zone. This mineralization is only known to exist southeast of Cooke Lake and immediately south of Net Lake. A unit of chert, magnetite and pyrrhotite outcrops along

4480-426: Is burnt (oxidized) to give magnetite or wüstite of a defined particle size. The magnetite (or wüstite) particles are then partially reduced, removing some of the oxygen in the process. The resulting catalyst particles consist of a core of magnetite, encased in a shell of wüstite, which in turn is surrounded by an outer shell of iron metal. The catalyst maintains most of its bulk volume during the reduction, resulting in

4608-458: Is evidence that the sulfide mineralization does not have a volcanogenic origin. An unusual feature of this sulfide deposit is the large degree of magnetite at the actual showing. Studies have shown that the chert-magnetite iron formations in the West and North Pits of Sherman Mine extend under and along a series of small lakes from Vermilion Lake to Net Lake. These iron formations are located at roughly

4736-478: Is fairly clean and rounded rock faces. A well-known result of this process is Half Dome in Yosemite Valley . Magnetite Magnetite is a mineral and one of the main iron ores , with the chemical formula Fe Fe 3+ 2 O 4 . It is one of the oxides of iron , and is ferrimagnetic ; it is attracted to a magnet and can be magnetized to become a permanent magnet itself. With

4864-729: Is found throughout the belt, indicating lava erupted underwater. Its pyroclastic deposits are remnants of explosive volcanism . The oldest exposed rocks within the belt are fine to medium-grained basalts and andesites . Lava flow units range in thickness from 90 m (300 ft) to 1,500 m (4,900 ft) . Mafic agglomerate and breccia are relatively abundant, being either massive and undeformed, or sheared . Dacitic lava flows or tuffs overlie these metamorphosed volcanic rocks along with intermediate volcanic breccias, and are overlain by rhyolite lava flows and tuffs. Acidic lava flow units range in thickness from 90 m (300 ft) to 900 m (3,000 ft) and are common in

4992-457: Is located within felsic volcanic rocks of the Older Volcanic Complex and is capped by large, dark green, iron-rich tholeiitic basalts of the Arsenic Lake Formation. It has been interpreted that the sulfide zone represents a volcanogenic massive sulfide ore deposit based on the structure of the sulfide zone and the associated rock types. These ore deposits are created by volcanic-associated hydrothermal events in submarine environments. However, there

5120-491: Is minimal in contrast to that which creates rocks such as gneiss . Other rock alterations include small veins of quartz and epidote , vesicles filled with quartz, calcite and chlorite, extensive replacement of volcanic rock by silica or calcite, and calcite precipitation in extension fractures. Outcrops of silicified mafic pillow lava are found along and west of the Ontario Northland Railway, east of

5248-579: Is represented by basal mafic volcanic rocks in the nearby Huronian Supergroup. Final breakup formed a large group of mafic dike and sill swarms in the North American provinces 2.2–2.1 billion years ago. By the Paleoproterozoic era Kenorland had already rifted apart, and the TGB formed a small part of the supercontinent Columbia starting 1.9–1.8 billion years ago. Eastern India, Australia, Laurentia , Baltica , North China ,

Temagami Greenstone Belt - Misplaced Pages Continue

5376-492: Is roughly 3 km (1.9 mi) long and at least 0.5 km (0.31 mi) wide. It is uncertain if this deformation zone extends east of Tasse Lake. Many forms of rock alteration can be seen in the TGB. Its overall structure has attained greenschist grade metamorphism, even though amphibolite grade metamorphism surrounds the Chambers-Strathy Batholith. The metamorphism that creates greenschist

5504-453: Is severe foliation and minor ferroan carbonate across an area about 1 km (0.62 mi) wide. The Link Lake Deformation Zone, also known as the Link Lake Shear Zone, is an area of deformation 0.5 km (0.31 mi) wide and over 3 km (1.9 mi) long in Strathy Township. It extends through Link Lake to east of Highway 11, but it is uncertain whether it extends west of Link Lake because no expression of it has been found in

5632-606: Is sometimes found in large quantities in beach sand. Such black sands (mineral sands or iron sands ) are found in various places, such as Lung Kwu Tan in Hong Kong; California , United States; and the west coast of the North Island of New Zealand. The magnetite, eroded from rocks, is carried to the beach by rivers and concentrated by wave action and currents. Huge deposits have been found in banded iron formations. These sedimentary rocks have been used to infer changes in

5760-453: Is still not well understood, and there has been a general lag in applying more modern, interdisciplinary techniques to the study of biomagnetism. Electron microscope scans of human brain-tissue samples are able to differentiate between magnetite produced by the body's own cells and magnetite absorbed from airborne pollution, the natural forms being jagged and crystalline, while magnetite pollution occurs as rounded nanoparticles . Potentially

5888-875: Is the Sierra Nevada Batholith , which is a continuous granitic formation that makes up much of the Sierra Nevada in California. An even larger batholith, the Coast Plutonic Complex , is found predominantly in the Coast Mountains of western Canada; it extends for 1,800 kilometers and reaches into southeastern Alaska. A batholith is an exposed area of (mostly) continuous plutonic rock that covers an area larger than 100 square kilometers (40 square miles). Areas smaller than 100 square kilometers are called stocks . However,

6016-480: Is unclear whether volcanic rocks in the Rib Lake area are part of the TGB, as they have not been mapped in any detail. With the existence of Early Archean age tholeiitic and/or calc-alkaline mafic to intermediate volcanic rocks, they may represent a minor continuation of the belt, which is located about 6 km (3.7 mi) to the southwest. Small intrusions and pyroclastics of mafic composition are also present in

6144-452: Is usually related to the presence of biogenic crystals of magnetite, which occur widely in organisms. These organisms range from magnetotactic bacteria (e.g., Magnetospirillum magnetotacticum ) to animals, including humans, where magnetite crystals (and other magnetically sensitive compounds) are found in different organs, depending on the species. Biomagnetites account for the effects of weak magnetic fields on biological systems. There

6272-527: The Congo craton to form the supercontinent Pannotia 600 million years ago. In contrast to Rodinia, Pannotia was short-lived. It rifted apart 545 million years ago, or only 65 million years after it formed. This resulted in the creation of at least four continents, namely Baltica, Siberia , Gondwana and Laurentia. By the Early Cambrian 514 million years ago, Laurenta was located on

6400-483: The Iceland Lake Pluton , as well as an adjacent rhyolitic lava flow, is about 2,736 million years old. Therefore, at least some intrusions were likely formed during the first volcanic phases in the belt and may have been conduits for volcanic eruptions. The variety of volcanic deposits and intrusions in the TGB indicates that magmatic activity played a significant part in its formation. Pillow lava

6528-587: The Late Triassic period some 152 million years ago, Pangaea split into two large continents, namely Gondwana and Laurasia . The TGB represented a minor portion of western Laurasia until it divided into Eurasia and North America about 94 million years ago. Since the Middle Miocene 14 million years ago, the TGB has been part of the Americas , a north–south trending landmass comprising

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6656-681: The Tetapaga Syncline , along the Milne-Sherman Road. Its colouration is from weathering of plagioclase , which comprises more than 50% of the intrusive rock. Several east-trending high-strain zones related to the Link Lake Deformation Zone , less than 1 m (3.3 ft) wide, are found in the intrusion, indicating that it formed at least before the last increment of strain along the Link Lake Deformation Zone. The dioritic intrusion might be

6784-579: The equator , Baltica was south of Laurenta, Siberia was just south of the equator east of Laurenta, and Gondwana lay mostly in the Southern Hemisphere . Subsequently, Baltica, Laurenta and microcontinent Avalonia collided in the Devonian period (416-359 million years ago) to form the continent Euramerica . This eventually started to collide with Gondwana and other landmasses to form supercontinent Pangaea 255 million years ago. In

6912-557: The 1995 claim block. A 21.2 m (70 ft) wide rusted zone within a dike was announced as containing values of $ 7.50 combined gold, copper and nickel . Little work has been completed in this area. In 1959 and 1960, Goldfields Mining conducted a basic airborne electromagnetic survey and magnetic survey over the property. Several holes were drilled and intersected mostly mafic to intermediate volcanic rocks and areas of stringer sulfides with pyrrhotite, pyrite and some chalcopyrite. No assays were reported. In 1970 E. L. McVeigh occupied

7040-479: The Amazon shield and portions of Antarctica formed the landmass until it ruptured 1.5–1.4 billion years ago. In the late Mesoproterozoic era 1.1 billion years ago, the Temagami belt was part of another supercontinent. This former supercontinent, known as Rodinia , included Oaxaquia, Rockall, Laurentia, Baltica, Australia, West Africa , South China , Amazonia, Mawson and Río de la Plata cratons, as well as

7168-709: The Arsenic Lake Formation are feldspar-phyric basaltic lava flows. This type of basalt contains tabular feldspar phenocrysts that range up to 2 cm (0.79 in) in cross section. Both pillowed and massive lava flows have been known to contain coarse feldspar. Coarse feldspar-bearing, iron tholeiitic basalts are more common east of Highway 11. A number of volcanic rocks comprise the Link Lake Formation, such as feldspar-phyric, calc-alkaline basalt and andesite lava flows and less abundant quartz and quartz-feldspar-phyric felsic lava flows. Feldspar-phyric basalt lava flows are normally pillowed. Pyroclastic deposits, quartz-phyric and feldspar-felsic rocks are also present. The largest of

7296-484: The Big Dan Shear Zone and adjacent to Outlet Bay and Boot Bay of Net Lake. This form of alteration occurs in deformation zones and is the product of low temperature seawater alteration. Volcanic rock replaced by carbonate is commonly found in the Northeast Arm Deformation Zone, the Link Lake Shear Zone and in the Net Lake-Vermilion Lake Deformation Zone. Within the high strain zones, carbonate

7424-561: The Copperfields mill had treated 9,125 oz (258,700 g) of gold, 175,979 oz (4,988,900 g) of silver and 76,982,986 lb (34,918,895 kg) of copper. Along the southeastern margin of the Net Lake-Vermilion Lake Deformation Zone lies the abandoned Beanland Mine property. Exploration work in 1937–1938 resulted in the creation of a three level 154 m (505 ft) mine shaft. In February 1992, Deak Resources completed diamond drilling and bulk sampling at

7552-477: The Earth's crust during the formation of the TGB. At least some of these dikes may have been subvolcanic feeders that produced known calc-alkalic felsic volcanic events in the belt. Many pyroxenite dikes less than 2 m (6.6 ft) wide intrude every geologic formation in the township. A pyroxenite dike east of Highway 11 extends roughly to the north-northwest while two others, north of Arsenic Lake , extend to

7680-478: The Geographical Names Board of Canada agreed to change the name spelling to Temagami on March 27, 1968. Nevertheless, the original spelling (Timagami) has appeared in documents published after the renaming, including Kent C. Condie's 1981 book Archean Greenstone Belts . In May 1995 Pacific Mariner Exploration carried out a small drilling program on its properties in Strathy Township to estimate

7808-431: The Link Lake Deformation Zone. These dark compressed pyroclastics have been interpreted to be pumice . Some of the subsequence pyroclastic deposits contain fragments of pyrite and quartz, suggesting that discharged sulfide hydrothermal activity took place throughout the volcanic source area. Resedimented felsic, epiclastic and turbiditic sediments compose the Turtle Lake Formation. The base of this formation consists of

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7936-458: The Northeast Arm Deformation Zone, the Link Lake Shear Zone and the Net Lake-Vermilion Lake Deformation Zone are obvious high potential areas. A number of scattered pyrite deposits can be found throughout the Northeast Arm Deformation Zone. The high frequency of gold mineralization in and near the Net Lake-Vermilion Lake Deformation Zone suggests that this deformation zone may very well also contain gold deposits; at least 11 have been discovered within

8064-687: The Pampean terrane. Laurentia, which included the Superior craton and the TGB, is interpreted to have formed the core of Rodinia because it is surrounded by passive margins formed during the breakup of the supercontinent some 750 million years ago. After Rodinia broke apart, its southern half traveled south and crossed the South Pole while its northern half traveled northward to the North Pole . The two halves of Rodinia eventually collided with

8192-527: The QFM buffer. At still lower oxygen levels, magnetite forms a buffer with wüstite known as the MW buffer. The QFM and MW buffers have been used extensively in laboratory experiments on rock chemistry. The QFM buffer, in particular, produces an oxygen fugacity close to that of most igneous rocks. Commonly, igneous rocks contain solid solutions of both titanomagnetite and hemoilmenite or titanohematite. Compositions of

8320-508: The Sherman Mine area. Therefore, the Link Lake Shear Zone might be a northern extension of the Northeast Arm Deformation Zone further south. Strain intensity of the Link Lake Shear Zone is diverse. Generally, the greatest strain intensity is throughout pyroclastic rocks. Extending from the western boundary of central Chambers Township through Tasse Lake to the east is the Tasse Lake Deformation Zone . This deformation zone

8448-459: The Temagami belt because they are adjacent to rocks that contain certain types of mineralization . At the Link Lake Formation, good evidence for copper - zinc massive sulfide deposits has been discovered in associated volcanic rocks. Some gold mineralization may also be associated with volcanic vents. Studies of greenstone terranes in the Superior craton have shown that large gold deposits are associated with regional deformation zones. Therefore,

8576-534: The Vermilion Lake and Link Lake areas. The felsic tuffs are normally altered and sheared. The most recent intrusive activity in the TGB was the formation of a rhyolite porphyry dike 2687 ± 2 million years ago. This age correlates well with the 2675–2700 million year old intrusions throughout the Abitibi Subprovince, but the 2736 million year old magmatic events in the TGB are older than

8704-491: The West and North Pits of Sherman Mine came from this chert-magnetite iron formation unit while chert-magnetite iron formations at the South and East Pits compose the Turtle Lake Formation. The South and East Pit iron formations reach thicknesses of 30 m (98 ft) and overlie a thinly bedded turbidite package on the southern limb of the Tetapaga Syncline. A white palladium mercury telluride mineral known as temagamite

8832-429: The Younger Volcanic Complex. It is situated in the core of the Tetapaga Syncline. Not much is known about this volcanic formation because only a small portion of it remains exposed in western Strathy Township. Many north-trending shear zones intersect iron-rich tholeiitic basalts of the Arsenic Lake Formation. These zones range in width from less than 1 m (3.3 ft) up to 5 m (16 ft) , and might maintain

8960-493: The area. In 1956 Silanco carried out geophysics south of Whitney Lake. In 1964 Nickel Rim Mines Ltd. had a greatest result of 1.30 oz (37 g) of gold per ton. The exploration and mining activity south of Gillies Limit Township observed nickel, copper and platinum group metals at Cuniptau Mine and gold, silver and copper at the Big Dan and Little Dan mines. Because of the high mineralization, several mines have opened in

9088-506: The belt. Sherman Mine, northwest of the town of Temagami, was a major producer of iron ore . Mining operations began in 1968, and workings consisted of seven open pits : North Pit, East Pit, South Pit, West Pit and three relatively small open pits known as the Turtle Pits. A railroad was built from the Ontario Northland Railway to Sherman Mine in the 1960s to make transportation and shipping of iron ore easier and faster across Ontario. To

9216-460: The bottom of the fluid, allowing the contaminants to be removed and the magnetite particles to be recycled and reused. This method works with radioactive and carcinogenic particles as well, making it an important cleanup tool in the case of heavy metals introduced into water systems. Another application of magnetic nanoparticles is in the creation of ferrofluids . These are used in several ways. Ferrofluids can be used for targeted drug delivery in

9344-410: The brain – magnetite, hemoglobin (blood) and ferritin (protein), and areas of the brain related to motor function generally contain more iron. Magnetite can be found in the hippocampus . The hippocampus is associated with information processing, specifically learning and memory. However, magnetite can have toxic effects due to its charge or magnetic nature and its involvement in oxidative stress or

9472-452: The calcite alteration zone was located within the Link Lake Shear Zone, it did not form inside the zone of the highest strain. The TGB contains massive banded iron formations and several precious metal and base metal deposits. The banded iron formations range from 1 m (3.3 ft) to 2 m (6.6 ft) to more than 150 m (490 ft) thick. Remnants of volcanic vents are an important locator for mineral potential in

9600-565: The characteristic nanoparticles were found in the brains of 37 people: 29 of these, aged 3 to 85, had lived and died in Mexico City, a significant air pollution hotspot. Some of the further eight, aged 62 to 92, from Manchester, England, had died with varying severities of neurodegenerative diseases. Such particles could conceivably contribute to diseases like Alzheimer's disease . Though a causal link has not yet been established, laboratory studies suggest that iron oxides such as magnetite are

9728-683: The closest exposed portion of the Abitibi Subprovince, about 120 km (75 mi) north of Kirkland Lake . Along with nearby granitic intrusions, the TGB is bounded by layers of rock comprising the Huronian Supergroup . Strathy Township is dominated by metamorphosed volcanic rocks of the northeastern portion of the belt. It is approximately 24 km (15 mi) north of the Grenville Front Tectonic Zone . The volcanic rocks possibly total as much as 6,000 m (20,000 ft) thick. However, portions of

9856-418: The coarse thicker parts of lava flows, but are interpreted to be partly intrusive, likely conduits that produced mafic volcanism. A layered intrusion composed of diorite, pyroxenite , gabbro and anorthositic gabbro has been found in northwestern Strathy Township. Pyrrhotite is common in associated pyroclastic rock . Several northeast-trending shear zones less than 5 m (16 ft) wide intersect

9984-540: The community. This caused a large attitudinal change from a few months earlier when the mine was associated with much of Temagami. The closure also had a significant impact on the economy of Temagami. There is still iron ore at Sherman Mine, but Dofasco were able to obtain it more cheaply elsewhere. The Kanichee Mine property, formerly known as Cuniptau Mine, was first discovered in the early 1900s just before World War I began. A 7.3 m (24 ft) mine shaft with 670 m (2,200 ft) of underground lateral workings

10112-555: The continents of North America and South America . The name "Temagami" is Ojibwe in origin, meaning "deep clear water"; until 1968 it was spelt as "Timagami". This spelling of the name appeared on all official maps and related documents when it was adopted on June 25, 1906. In early 1968 the Canada Post Office applied to the Geographical Names Board of Canada for a spelling reform to Temagami at

10240-720: The creation of the Net Lake-Vermilion Lake Deformation Zone. At the Younger Volcanic Complex, gold exists in quartz veins containing base metal sulfides. It is also known to exist in pyrite associated with deformed magnetite-rich iron formations, sericitized and carbonatized felsic volcanic rock, quartz- pyrrhotite - chalcopyrite - pentlandite -pyrite zones within deformation zones and in north-trending, chloritized shear zones containing arsenopyrite , pyrrhotite, pyrite and chalcopyrite. A variety of iron, copper, arsenic and zinc ores such as arsenopyrite, pyrrhotite, pyrite and chalcopyrite with sphalerite, are present as small veins and in quartz veins throughout north-trending shear zones that cut

10368-479: The deformation zone. The TGB consists of two large volcanic sequences that were formed during several phases of volcanic activity. These two sequences, known as the Older and Younger volcanic complexes, consist of volcanic rocks ranging in composition from felsic to mafic. The Older Volcanic Complex is composed mainly of felsic lava flows and pyroclastic deposits with smaller amounts of mafic volcanic rocks. It underlies

10496-459: The dikes at this location is unknown. The most recent phase of tectonic activity along the Big Dan Shear Zone resulted in the displacement of a Proterozoic dike composed of diabase, which intersects the zone. A similar abundance of felsic dikes are adjacent to Arsenic Lake just west of Highway 11, indicating similar repetitive tectonism also occurred along that structural zone. Therefore, the north-trending shear zones may have been active for at least

10624-611: The east. This includes a dike exposed along the Kanichee Mine Road in Temagami North , where it intrudes the large granitic Chambers-Strathy Batholith. A series of northwest-trending dikes composed of diabase may represent extensions of the 1,250 million year old Sudbury dike swarm . This dike swarm is older than the Lake Wanapitei impact crater but younger than the meteorite impact that created

10752-610: The edifice, extending along the Net Lake-Vermilion Lake Deformation Zone . This layered intrusion might be similar in age to the Kanichee layered intrusive complex , and may represent a magma chamber that was the source of tholeiitic volcanic activity. The Kanichee layered intrusive complex, also known as the Kanichee Intrusion and Ajax Intrusion, is the most voluminous mafic- ultramafic body in metamorphosed felsic and mafic volcanic rocks of

10880-406: The exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetized pieces of magnetite, called lodestone , will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism. Magnetite is black or brownish-black with a metallic luster, has a Mohs hardness of 5–6 and leaves

11008-442: The existence of two felsic lava flows that outcrop between Link Lake and Turtle Lake . The aspect of the most extensive felsic lava flow indicates that the volcanic vent they erupted from was adjacent to the western portion of Link Lake. Additionally, differentiation of facies and directions in which the lava traveled exist in course grained, resedimented conglomerate . This suggests that a more prominent structure, perhaps evidence of

11136-544: The formation of the supercontinent Kenorland between 2.8 and 2.6 billion years ago. This large landmass consisted of the Baltic and Siberian shields of Eurasia and Archean provinces of North America, including the Superior craton of which the Temagami belt occupies a part. Rifting of Kenorland began 2.45 billion years ago in Ontario with the formation of several large igneous provinces . Initial rifting

11264-423: The former Temagami garbage dump. These dikes are not known to extend across the Link Lake Deformation Zone, suggesting that they might represent the feeders of a minor volcanic vent, manifest now by felsic lava flows. Because certain lithologies can be correlated through the Link Lake Deformation Zone, it is unlikely that the lack of felsic dikes south of the former town dump area is an expression of displacement along

11392-402: The human body. The magnetization of the particles bound with drug molecules allows "magnetic dragging" of the solution to the desired area of the body. This would allow the treatment of only a small area of the body, rather than the body as a whole, and could be highly useful in cancer treatment, among other things. Ferrofluids are also used in magnetic resonance imaging (MRI) technology. For

11520-483: The insight they provide into crustal evolution and the tectonics of the early Earth. The TGB is 25 km (16 mi) wide and 32 km (20 mi) long. It contains the southernmost remnants of Archean intrusive and supracrustal rocks in Eastern Ontario , as well as some of the most ancient felsic magmatic events in this section of the Superior craton. Uranium-lead dating has established that

11648-611: The instigation of the general public. The Executive Secretary of this committee subsequently applied to the Lands and Surveys Branch of the Ontario Department of Lands and Forests. This former department, now part of Ministry of Natural Resources , corresponded with the proposed renaming of Timagami on March 20, 1968, as well as for Lake Timagami, Timagami Island and the Timagami River. Further improvements occurred when

11776-414: The iron-rich tholeiitic basalts of the Arsenic Lake Formation. Dikes composed of quartz-feldspar porphyry run parallel to or lie within the shear zones and are cut by the mineralization. Chalcopyrite occupies later fractures which intersect massive arsenopyrite. Sparse quartz veins normally exist in or adjacent to the arsenopyrite-rich zones. Several northeast-trending deformation zones intersect pyroxenite of

11904-581: The large Sudbury Basin crater about 1,850 million years ago. Therefore, the TGB predates these two impact craters, the Sudbury crater of which is the seconed largest known impact crater on Earth. Volcanic vents composed of felsic rocks are thought to have been located at the iron-bearing Sherman Mine, the former Temagami garbage dump and adjacent to the Milne Townsite . Remnants of a large volcanic vent are present west of Sherman Mine, including

12032-674: The less common felsic lava flows is located between Link Lake and Turtle Lake. It is 2.5 km (1.6 mi) long and less than 200 m (660 ft) thick. The thickest portion of this lava flow or dome is located at the western end of Link Lake, where it is likely associated with a volcanic vent. The bulk of felsic rock in the Link Lake Formation occurs as subaqueous pyroclastic flow deposits. Subaerial pyroclastics are normally quartz-phyric and range up to 30 cm (12 in) in crosssection. Dark green subaerial pyroclastics composed of chlorite and sericite are uncommon and have sustained preferential compression in response to shear throughout

12160-549: The likelihood of base metal deposits. A 215 m (705 ft) hole was drilled under Net Lake in Temagami North, but its collapse prevented the survey's completion. As a result, little is known about its geophysical features. Most of the property was influenced by Net Lake and included ten adjacent mining claims. At least five explorations took place in the Strathy Township property before 1995. In 1934 Strathy Basin and Erie Canadian Mines conducted prospected sections of

12288-448: The magnetic fields the organism was exposed to, potentially allowing scientists to learn about the migration of the organism or about changes in the Earth's magnetic field over time. Living organisms can produce magnetite. In humans, magnetite can be found in various parts of the brain including the frontal , parietal , occipital , and temporal lobes , brainstem , cerebellum and basal ganglia . Iron can be found in three forms in

12416-461: The magnetite with needle-shaped particles of gamma ferric oxide (γ-Fe 2 O 3 ). Approximately 2–3% of the world's energy budget is allocated to the Haber Process for nitrogen fixation, which relies on magnetite-derived catalysts. The industrial catalyst is obtained from finely ground iron powder, which is usually obtained by reduction of high-purity magnetite. The pulverized iron metal

12544-455: The majority of batholiths visible at the surface (via outcroppings) have areas far greater than 100 square kilometers. These areas are exposed to the surface through the process of erosion accelerated by continental uplift acting over many tens of millions to hundreds of millions of years. This process has removed several tens of square kilometers of overlying rock in many areas, exposing the once deeply buried batholiths. Batholiths exposed at

12672-472: The mine and 3,000 tons of rock was shipped to its Kerr Mill in Virginiatown . The estimated reserves, before this work, were 8,778 tons averaging 0.31 oz (8.8 g) of gold per ton across a 1.7 m (5.6 ft) mining width and 24,000 tons averaging 0.21 oz (6.0 g) of gold per ton across a 1.6 m (5.2 ft) mining width. The mineralized zone is described as

12800-417: The mine. The municipality of Temagami made several approaches to Dofasco before the closer of Sherman Mine, offering a partnership in the community's future in terms of shared funding for a Sherman Park. However, it was informed during discussions with Dofasco's media executives that in the future they could not be counted on for maintenance funds for parks or anything else that was being done in partnership with

12928-418: The mineral pairs are used to calculate oxygen fugacity: a range of oxidizing conditions are found in magmas and the oxidation state helps to determine how the magmas might evolve by fractional crystallization . Magnetite also is produced from peridotites and dunites by serpentinization . Lodestones were used as an early form of magnetic compass . Magnetite has been a critical tool in paleomagnetism ,

13056-596: The mineral. In the municipalities of Molinaseca, Albares, and Rabanal del Camino, in the province of León (Spain), there is a magnetite deposit in Ordovician terrain, considered one of the largest in Europe. It was exploited between 1955 and 1982. Deposits are also found in Norway , Romania , and Ukraine . Magnetite-rich sand dunes are found in southern Peru. In 2005, an exploration company, Cardero Resources, discovered

13184-540: The nearby fold axis of the Tetapaga Syncline, but remains undeformed by the western expression of the Net Lake-Vermilion Lake Deformation Zone. To the north and northeast, the massive Chambers-Strathy Batholith was formed during one magmatic event. It consists of intrusive rocks ranging from pink to grey quartz monzonite to granodiorite and intrudes metamorphosed volcanic rocks of the TGB. The Iceland Lake Pluton, situated in Strathcona and Briggs townships, consists of

13312-412: The north, Temagami North was constructed as a resource town in the 1960s to supply Sherman Mine. With an average overall grade of 25% iron, the mine produced approximately 10,700 tons of crude ore per day and its mill capacity was 1,000,000 long tons (1.0 × 10 kg) of iron ore pellets per year. Operations at Sherman Mine ceased in 1990 after its owner Dofasco announced that they would be closing

13440-405: The northern TGB. It is an oval-shaped layered intrusion that was formed during five phases of magmatic activity. A series of south-southeast dipping cyclic magmatic layers make up the intrusion, similar to those of the surrounding metamorphosed volcanic rocks, indicating that the rocks of the intrusion were formed horizontally and likely close to the surface. Numerous magmatic events may have breached

13568-599: The northwestern portion of the shear zone have shifted to the northeast while the volcanic rocks comprising its southeastern portion have shifted to the southwest. Along the northeastern arm of Lake Temagami in Strathcona Township lies the Northeast Arm Deformation Zone . This northeast-trending shear zone has not been studied in detail, but casual studies of many islands along the northeastern arm of Lake Temagami have shown that there

13696-702: The oxygen content of the atmosphere of the Earth. Large deposits of magnetite are also found in the Atacama region of Chile ( Chilean Iron Belt ); the Valentines region of Uruguay; Kiruna , Sweden; the Tallawang region of New South Wales; and in the Adirondack Mountains of New York in the United States. Kediet ej Jill , the highest mountain of Mauritania , is made entirely of

13824-403: The presence of mineralizers such as 0.1   M HI or 2   M NH 4 Cl and at 0.207   MPa at 416–800 °C, magnetite grew as crystals whose shapes were a combination of rhombic-dodechahedra forms. The crystals were more rounded than usual. The appearance of higher forms was considered as a result from a decrease in the surface energies caused by the lower surface to volume ratio in

13952-405: The production of free radicals . Research suggests that beta-amyloid plaques and tau proteins associated with neurodegenerative disease frequently occur after oxidative stress and the build-up of iron. Some researchers also suggest that humans possess a magnetic sense, proposing that this could allow certain people to use magnetoreception for navigation. The role of magnetite in the brain

14080-534: The relationship between magnetite and ferritin . In tissue, magnetite and ferritin can produce small magnetic fields which will interact with magnetic resonance imaging (MRI) creating contrast. Huntington patients have not shown increased magnetite levels; however, high levels have been found in study mice. Due to its high iron content, magnetite has long been a major iron ore . It is reduced in blast furnaces to pig iron or sponge iron for conversion to steel . Audio recording using magnetic acetate tape

14208-493: The remains of a magma chamber that was the product of calc-alkaline feldspar - phyric felsic volcanism, the erupted products of which are mostly located in the Sherman Mine area. At least three large granitoid intrusions penetrate the TGB. The Spawning Lake Stock in Briggs and Chambers townships contains megacrysts that reach 2 cm (0.79 in) to 3 cm (1.2 in) in diameter. It shears through

14336-427: The rounded crystals. Magnetite has been important in understanding the conditions under which rocks form. Magnetite reacts with oxygen to produce hematite , and the mineral pair forms a buffer that can control how oxidizing its environment is (the oxygen fugacity ). This buffer is known as the hematite-magnetite or HM buffer. At lower oxygen levels, magnetite can form a buffer with quartz and fayalite known as

14464-444: The same stratigraphic position as the magnetite-bearing iron formation on the southwestern shore of Net Lake. A northwest-trending cross fault is accompanied by drag folding of a chert-magnetite iron formation unit southeast of Cooke Lake. Also exposed in this area is a dark yellow 40 cm (16 in) wide quartz vein composed of pyrite that cross cuts the iron formation at the northeastern end. This west-northwest trending quartz vein

14592-747: The sequence might have been repeatedly sheared by one or several local fault zones. Every large volcanic event is capped by metamorphosed sedimentary rocks and/or iron formations . The metamorphosed sedimentary units range in thickness from 60 m (200 ft) to 300 m (980 ft) and consist of laminated slate and greywacke with or without volcanogenic tuffs. The iron formations are composed of alternate layers of magnetite , white quartzite , jasper , grey cherty quartz, and/or tremolite - chlorite tuff. They are intruded by sills composed of medium-grained, white-weathering, quartz diorite that range in thickness from 100 m (330 ft) to 210 m (690 ft) . These rocks are similar to

14720-420: The sign of the magnetocrystalline anisotropy constant changes from positive to negative. The Curie temperature of magnetite is 580 °C (853 K; 1,076 °F). If magnetite is in a large enough quantity it can be found in aeromagnetic surveys using a magnetometer which measures magnetic intensities. Solid magnetite particles melt at about 1,583–1,597 °C (2,881–2,907 °F). Magnetite

14848-531: The size of the open pit and removed the shaft pillar. The open pit and underground workings have remain flooded since the mine closed in the 1970s. Copperfields Mine , originally known as Temagami Mine, extracted both base and precious metals on Temagami Island in Lake Temagami from March 1955 until its closer in February 1972. A 200-ton mill refined ore from two open pits and underground workings off

14976-424: The southwest shore of Net Lake at Temagami North. Pyrrhotite, the most common sulfide mineral, occurs as small veins and disseminations. Small amounts of pyrite, sphalerite and exsolved pentlandite and chalcopyrite are present with the pyrrhotite. The main exposure lies immediately south of the Kanichee Mine Road, which branches off Highway 11. Minor gold and copper values constitute this zone. This sulfide-bearing unit

15104-465: The surface are subjected to huge pressure differences between their former location deep in the earth and their new location at or near the surface. As a result, their crystal structure expands slightly over time. This manifests itself by a form of mass wasting called exfoliation . This form of weathering causes convex and relatively thin sheets of rock to slough off the exposed surfaces of batholiths (a process accelerated by frost wedging ). The result

15232-405: The surface from a zone of partial melting near the base of the Earth's crust. Traditionally, these plutons have been considered to form by ascent of relatively buoyant magma in large masses called plutonic diapirs . Because the diapirs are liquified and very hot, they tend to rise through the surrounding native country rock , pushing it aside and partially melting it. Most diapirs do not reach

15360-652: The surface to form volcanoes , but instead they slow down, cool, and usually solidify 5 to 30 kilometers underground as plutons (hence the use of the word pluton ; in reference to the Roman god of the underworld Pluto ). An alternate view is that plutons are formed by aggregation of smaller volumes of magma that ascend as dikes . A batholith is formed when many plutons converge to form a huge expanse of granitic rock. Some batholiths are mammoth, paralleling past and present subduction zones and other heat sources for hundreds of kilometers in continental crust . One such batholith

15488-405: The surface to produce volcanic eruptions. The overall structure of the intrusion indicates it is cylindrical in shape and has a long axis plunging to the southeast at a somewhat steep angle. Its fairly steep angled axis was formed by at least one period of deformation that similarly folded and deformed the surrounding volcanic rocks. An intrusion of light-coloured diorite lies at the northern end of

15616-453: The upper beak for magnetoreception , which (in conjunction with cryptochromes in the retina ) gives them the ability to sense the direction, polarity , and magnitude of the ambient magnetic field . Chitons , a type of mollusk, have a tongue-like structure known as a radula , covered with magnetite-coated teeth, or denticles . The hardness of the magnetite helps in breaking down food. Biological magnetite may store information about

15744-603: Was completed on all five levels. Production continued at the Big Dan Occurrences during the early 20th century. Two shallow mine shafts were created in 1906 and were used to ship ore out of the mine. At least 0.358 oz (10.1 g) of gold per ton was sent during this period. The mine was constructed in a 610 m (2,000 ft) , north striking mineralized portion of the Big Dan Shear Zone. Batholith A batholith (from Ancient Greek bathos  'depth' and lithos  'rock')

15872-482: Was completed on two levels in 1934. At least 11 mine claims occupied the area at the time. The core of a widespread massive sulfide deposit composed of palladium, nickel, copper, gold, cobalt, platinum and silver was mined out from underground and by an open pit from 1934 to 1936. Since 1938, at least seven different ownerships have held the Kanichee Mine property. Subsequent mining from 1974 to 1975 increased

16000-480: Was developed in the 1930s. The German magnetophon first utilized magnetite powder that BASF coated onto cellulose acetate before soon switching to gamma ferric oxide for its superior morphology. Following World War II , 3M Company continued work on the German design. In 1946, the 3M researchers found they could also improve their own magnetite-based paper tape, which utilized powders of cubic crystals, by replacing

16128-463: Was discovered in 1973 on Temagami Island in Lake Temagami. It is present as microscopic inclusions within chalcopyrite in association with other rare tellurides, such as merenskyite , stuetzite and hessite . Also discovered on the island was an unnamed palladium mercury silver telluride mineral, the composition and optical properties of which are significantly different from those of temagamite. The TGB, at 2.7 billion years old, dates back to

16256-443: Was discovered with widespread pyrrhotite in sheared mafic rocks. Gold mineralization was discovered with pyrite in slightly siliceous tuff. The highest assessment was 1.30 oz (37 g) of gold per ton and 0.99% of nickel over 1.8 m (5.9 ft) , both from the same zone. Detailed work did not occur in the Rib Lake area of southern Gillies Limit Township and northern Best Township until 1968, when mapping took place, but it

16384-493: Was used to transport ore from the mine site. The high-grade copper deposit in which the mine extracted was discovered by Canadian geophysicist Norman Bell Keevil (1910–1989) in the mid-20th century during testing of a newly established airborne metal detector . It was the largest deposit of nearly pure chalcopyrite ever discovered in Canada. Keevil also financed other ventures, including what became Teck Resources . By February 1972,

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