|
Animikie Group
The Animikie Group is a geologic group composed of sedimentary and metasedimentary rock, having been originally deposited between 2,500 and 1,800 million years ago during the Paleoproterozoic era, within the Animikie Basin. This group of formations is geographically divided into the Gunflint Range, the Mesabi and Vermilion ranges, and the Cuyuna Range. On the map, the Animikie Group is the dark gray northeast-trending belt which ranges from south-central Minnesota, U.S., up to Thunder Bay, Ontario, Canada. The Gunflint Iron Range is the linear black formation labeled G, the Mesabi Iron Range is the jagged black linear formation labeled F, and Cuyuna Iron Range is the two black spots labeled E. The gabbro of the Duluth Complex, intruded during the formation of the Midcontinent Rift, separates the Mesabi and Gunflint iron ranges; it is shown by the speckled area wrapping around the western end of Lake Superior. Banded-iron formations are iron formations which formed about 2,00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siderite
Siderite is a mineral composed of iron(II) carbonate (FeCO3). Its name comes from the Ancient Greek word (), meaning "iron". A valuable iron ore, it consists of 48% iron and lacks sulfur and phosphorus. Zinc, magnesium, and manganese commonly substitute for the iron, resulting in the siderite-smithsonite, siderite-magnesite, and siderite-rhodochrosite solid solution series. Siderite has Mohs hardness of 3.75 to 4.25, a specific gravity of 3.96, a white streak and a vitreous or pearly luster. Siderite is antiferromagnetic below its Néel temperature of that can assist in its identification. It crystallizes in the trigonal crystal system; crystals are rhombohedral in shape, typically with curved and striated faces. It also occurs in masses. Color ranges from yellow to dark brown or black, the latter being due to the presence of manganese. Siderite is commonly found in hydrothermal veins, and is associated with barite, fluorite, galena, and others. It is also a common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limonite
Limonite () is an iron ore consisting of a mixture of hydrated iron(III) oxide-hydroxides in varying composition. The generic formula is frequently written as , although this is not entirely accurate as the ratio of oxide to hydroxide can vary quite widely. Limonite is one of the three principal iron ores, the others being hematite and magnetite, and has been mining, mined for the production of iron since at least 400 BC. Names Limonite is named for the Ancient Greek word ( ), meaning "wet meadow", or ( ), meaning "marshy lake", as an allusion to its occurrence as in meadows and marshes. In its brown form, it is sometimes called brown hematite or brown iron ore. Characteristics Limonite is relatively density, dense with a specific gravity varying from 2.7 to 4.3.Northrop, Stuart A. (1959) "Limonite" ''Minerals of New Mexico'' (revised edition) University of New Mexico Press, Albuquerque, New Mexico, pp. 329–333, It is usually medium to dark yellowish brown in color. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematite
Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of . It has the same crystal structure as corundum () and ilmenite (). With this it forms a complete solid solution at temperatures above . Hematite occurs naturally in black to steel or silver-gray, brown to reddish-brown, or red colors. It is mined as an important ore mineral of iron. It is electrically conductive. Hematite varieties include ''kidney ore'', ''martite'' ( pseudomorphs after magnetite), ''iron rose'' and ''specularite'' ( specular hematite). While these forms vary, they all have a rust-red streak. Hematite is not only harder than pure iron, but also much more brittle. The term ''kidney ore'' may be broadly used to describe botryoidal, mammillary, or reniform hematite. Maghemite is a polymorph of hematite (γ-) with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precipitation (chemistry)
In an aqueous solution, precipitation is the "sedimentation of a solid material (a precipitate) from a liquid solution". The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant. The clear liquid remaining above the precipitated or the centrifuged solid phase is also called the supernate or supernatant. The notion of precipitation can also be extended to other domains of chemistry (organic chemistry and biochemistry) and even be applied to the solid phases (e.g. metallurgy and alloys) when solid impurities segregation (materials science), segregate from a solid phase. Supersaturation The precipitation of a compound may occur when its concentration exceeds its solubility. This can be due to temperature changes, solvent evaporation, or by mixing solvents. Precipitation occurs more rapidly from a strongly supersaturated solution. The formation of a pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Oxide
An iron oxide is a chemical compound composed of iron and oxygen. Several iron oxides are recognized. Often they are non-stoichiometric. Ferric oxyhydroxides are a related class of compounds, perhaps the best known of which is rust. Iron oxides and oxyhydroxides are widespread in nature and play an important role in many geological and biological processes. They are used as iron ores, pigments, catalysts, and in thermite, and occur in hemoglobin. Iron oxides are inexpensive and durable pigments in paints, coatings and colored concretes. Colors commonly available are in the " earthy" end of the yellow/orange/red/brown/black range. When used as a food coloring, it has E number E172. Stoichiometries Iron oxides feature as ferrous ( Fe(II)) or ferric ( Fe(III)) or both. They adopt octahedral or tetrahedral coordination geometry. Only a few oxides are significant at the earth's surface, particularly wüstite, magnetite, and hematite. * Oxides of FeII ** FeO: ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seawater
Seawater, or sea water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, 35 ppt, 600 mM). This means that every kilogram (roughly one liter by volume) of seawater has approximately of dissolved salts (predominantly sodium () and chloride () ions). The average density at the surface is 1.025 kg/L. Seawater is denser than both fresh water and pure water (density 1.0 kg/L at ) because the dissolved salts increase the mass by a larger proportion than the volume. The freezing point of seawater decreases as salt concentration increases. At typical salinity, it freezes at about . The coldest seawater still in the liquid state ever recorded was found in 2010, in a stream under an Antarctic glacier: the measured temperature was . Seawater pH is typically limited to a range between 7.5 and 8.4. However, there is no universally accepted reference pH-scale for seawater and the difference between measuremen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chert
Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a precipitation (chemistry), chemical precipitate or a diagenesis, diagenetic replacement, as in petrified wood. Chert is typically composed of the petrified remains of siliceous ooze, the biogenic sediment that covers large areas of the deep ocean floor, and which contains the silicon skeletal remains of diatoms, Dictyochales, silicoflagellates, and radiolarians. Precambrian cherts are notable for the presence of fossil cyanobacteria. In addition to Micropaleontology, microfossils, chert occasionally contains macrofossils. However, some chert is devoid of any fossils. Chert varies greatly in color, from white to black, but is most often found as gray, brown, grayish brown and light green to rusty redW.L. Roberts, T.J. Campbell, G.R. Rapp Jr., ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron is a chemical element; it has symbol Fe () 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, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michigan
Michigan ( ) is a peninsular U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, Upper Midwestern United States. It shares water and land boundaries with Minnesota to the northwest, Wisconsin to the west, Indiana and Illinois to the southwest, Ohio to the southeast, and the Canadian Provinces and territories of Canada, province of Ontario to the east, northeast and north. With a population of 10.14 million and an area of , Michigan is the List of U.S. states and territories by population, 10th-largest state by population, the List of U.S. states and territories by area, 11th-largest by area, and the largest by total area east of the Mississippi River.''i.e.'', including water that is part of state territory. Georgia (U.S. state), Georgia is the largest state by land area alone east of the Mississippi and Michigan the second-largest. The state capital is Lansing, Michigan, Lansing, while its most populous city is Detroit. The Metro Detroit r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
