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Spawning Lake Stock
The Spawning Lake Stock is an Archean age granitoid stock in Northeastern Ontario, Canada, located in Briggs Township and Chambers Township of Temagami. It intrudes through the Tetapaga Syncline, a major geologic fold in the Temagami Greenstone Belt. However, it remains undeformed by strain associated with the formation of the fold. The stock is intruded by dikes composed of biotite lamprophyre on its outer margins. See also *Iceland Lake Pluton *Chambers-Strathy Batholith The Chambers-Strathy Batholith, also called the Strathy-Chambers Batholith, is a large granitoid batholith complex in the Temagami region of Northeastern Ontario, Canada. Named for the Chambers and Strathy townships, its compositions range from pi ... References Geology of Temagami Archean magmatism Igneous petrology of Ontario Stocks (geology) {{NorthernOntario-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ... during the Archean was mostly a water world: there was continental crust, but much of it was under an ocean deeper than today's ocean. Except for some trace minerals, today's oldest continental crust dates back to the Archean. Much of the geological detail of the Archean has been destroyed by subsequent activity. The Earliest known life forms, earliest known life started in the Archean. Life was simple throughout the Archean, mostly represented by shallow-water microbial mats called stromatolites, and the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temagami Greenstone Belt
The Temagami Greenstone Belt (TGB) is a small 2.7 billion year old greenstone belt in the Temagami region of Northeastern Ontario, Canada. It represents a feature of the Superior craton, an ancient and stable part of the Earth's lithosphere that forms the core of the North American continent and Canadian Shield. The belt is composed of metamorphosed volcanic rocks that range in composition from basalt to rhyolite. These form the east-northeast trend of the belt and are overlain by metamorphosed sedimentary rocks. They were created during several volcanic episodes involving a variety of eruptive styles ranging from passive lava eruptions to viscous explosive eruptions. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archean Magmatism
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 during the Archean was mostly a water world: there was continental crust, but much of it was under an ocean deeper than today's ocean. Except for some trace minerals, today's oldest continental crust dates back to the Archean. Much of the geological detail of the Archean has been destroyed by subsequent activity. The earliest known life started in the Archean. Life was simple throughout the Archean, mostly represented by shallow-water microbial mats called stromatolites, and the atmosphere lacked free oxygen. Etymology and changes in classification The word ''Archean'' comes from the Greek word (), meaning 'beginning, origin'. It was first used in 1872, when it meant 'of the earliest geological age'. Before the Hadean Eon was recognized, the Archea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Temagami
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chambers-Strathy Batholith
The Chambers-Strathy Batholith, also called the Strathy-Chambers Batholith, is a large granitoid batholith complex in the Temagami region of Northeastern Ontario, Canada. Named for the Chambers and Strathy townships, its compositions range from pink to grey quartz monzonite to granodiorite and intrudes through rocks of the Temagami Greenstone Belt. See also *Iceland Lake Pluton *Spawning Lake Stock The Spawning Lake Stock is an Archean age granitoid stock in Northeastern Ontario, Canada, located in Briggs Township and Chambers Township of Temagami. It intrudes through the Tetapaga Syncline, a major geologic fold in the Temagami Greenstone ... References Batholiths of North America Igneous petrology of Ontario Geology of Temagami Strathy Township {{NorthernOntario-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceland Lake Pluton
The Iceland Lake Pluton, formerly known as the Ingall Lake Batholith, is a large granitic intrusion in Briggs and Strathcona townships of Temagami, Northeastern Ontario, Canada. It is one of the three separate granitoid intrusions that constitute the Temagami Greenstone Belt, consisting of rocks ranging from diorite to quartz monzonite. The age of the intrusion is estimated to be about 2,736 million years old, as well as an adjacent rhyolitic lava flow using the uranium–lead dating technique. This suggests that the Iceland Lake Pluton might be the remnants of a magma chamber of a volcano that erupted felsic magma. The pluton is overlain by sediments of the younger Huronian Supergroup. Chlorite trondhjemite of the Iceland Lake Pluton is exposed along the Lake Temagami Access Road and Iceland Lake. See also *Spawning Lake Stock *Chambers-Strathy Batholith The Chambers-Strathy Batholith, also called the Strathy-Chambers Batholith, is a large granitoid batholith complex in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamprophyre
Lamprophyres () are uncommon, small-volume ultrapotassic igneous rocks primarily occurring as dikes, lopoliths, laccoliths, stocks, and small intrusions. They are alkaline silica-undersaturated mafic or ultramafic rocks with high magnesium oxide, >3% potassium oxide, high sodium oxide, and high nickel and chromium. Lamprophyres occur throughout all geologic eras. Archaean examples are commonly associated with lode gold deposits. Cenozoic examples include magnesian rocks in Mexico and South America, and young ultramafic lamprophyres from Gympie in Australia with 18.5% MgO at ~250 Ma. Petrology Modern science treats lamprophyres as a catch-all term for ultrapotassic mafic igneous rocks which have primary mineralogy consisting of amphibole or biotite, and with feldspar in the groundmass. Lamprophyres are not amenable to classification according to modal proportions, such as the system QAPF due to peculiar mineralogy, nor compositional discrimination diagrams, such as TAS be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biotite
Biotite is a common group of phyllosilicate minerals within the mica group, with the approximate chemical formula . It is primarily a solid-solution series between the iron-endmember annite, and the magnesium-endmember phlogopite; more aluminous end-members include siderophyllite and eastonite. Biotite was regarded as a mineral ''species'' by the International Mineralogical Association until 1998, when its status was changed to a mineral ''group''. The term ''biotite'' is still used to describe unanalysed dark micas in the field. Biotite was named by J.F.L. Hausmann in 1847 in honor of the French physicist Jean-Baptiste Biot, who performed early research into the many optical properties of mica. Members of the biotite group are sheet silicates. Iron, magnesium, aluminium, silicon, oxygen, and hydrogen form sheets that are weakly bound together by potassium ions. The term "iron mica" is sometimes used for iron-rich biotite, but the term also refers to a flaky micaceous form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dike (geology)
A dike or dyke, in Geology, geological usage, is a sheet of rock that is formed in a Fracture (geology), fracture of a pre-existing rock body. Dikes can be either Intrusive rock, magmatic or Sedimentary rock, sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetapaga Syncline
The Tetapaga Syncline, also known as the Lake Tetapaga Syncline, is a northeasterly trending syncline in Northeastern Ontario, Canada, located in Strathy Township of the municipality of Temagami. It represents a major structural feature in the Temagami Greenstone Belt, with dark green, massive and pillow lava, pillowed iron-rich tholeiitic basalts forming its core. References Structural geology Geology of Temagami {{struct-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granitoid
A granitoid is a generic term for a diverse category of coarse-grained igneous rocks that consist predominantly of quartz, plagioclase, and alkali feldspar. Granitoids range from plagioclase-rich tonalites to alkali-rich syenites and from quartz-poor monzonites to quartz-rich quartzolites. As only two of the three defining mineral groups (quartz, plagioclase, and alkali feldspar) need to be present for the rock to be called a granitoid, foid-bearing rocks, which predominantly contain feldspars but no quartz, are also granitoids. The terms ''granite'' and ''granitic rock'' are often used interchangeably for granitoids; however, granite is just one particular type of granitoid. Granitoids are diverse; no classification system for granitoids can give a complete and unique characterization of the origin, compositional evolution, and geodynamic environment for the genesis of a granitoid. Accordingly, multiple granitoid classification systems have been developed such as those based o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrusive Rock
Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form ''Igneous intrusion, intrusions'', such as batholiths, dike (geology), dikes, Sill (geology), sills, laccoliths, and volcanic necks.Intrusive RocksIntrusive rocks accessdate: March 27, 2017.Igneous intrusive rocks, accessdate: March 27, 2017.Britannica.comintrusive rock , geology , Britannica.com accessdate: March 27, 2017. Intrusion is one of the two ways igneous rock can form. The other is extrusive rock, extrusion, such as a Types of volcanic eruptions, volcanic eruption or similar event. An intrusion is any body of intrusive igneous rock, formed from magma that cools and solidifies within the crust of the planet. In contrast, an ''extrusion'' consists of extrusive rock, formed above the surface of the crust. Some geologists use the term plutonic rock synonymously with intrusive rock, but other geologists subdivide intrusive rock, by crystal size, into coarse-grai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
