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Iron Range
The term Iron Range refers collectively or individually to a number of elongated iron-ore mining districts around Lake Superior in the United States and Canada. Much of the ore-bearing region lies alongside the range of granite hills formed by the Giants Range batholith. These cherty iron ore deposits are Precambrian in the Vermilion Range and middle Precambrian in the Mesabi and Cuyuna ranges, all in Minnesota. The Gogebic Range in Wisconsin and the Marquette Iron Range and Menominee Range in Michigan have similar characteristics and are of similar age. Natural ores and concentrates were produced from 1848 until the mid-1950s, when taconites and jaspers were concentrated and pelletized, and started to become the major source of iron production. The mining districts are in Minnesota's Arrowhead region. The region's far eastern area, containing the Duluth Complex along the shore of Lake Superior, and the far northern area, along the Canada–U.S. border, are not associated w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Ranges
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 front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron Age. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duluth Complex
The Duluth Complex, the related Beaver Bay Complex, and the associated North Shore Volcanic Group are rock formations which comprise much of the basement bedrock of the northeastern part of the U.S. state of Minnesota in central North America. The Duluth and Beaver Bay complexes are intrusive rocks formed about 1.1 billion years ago during the Midcontinent Rift; these adjoin and are interspersed with the extrusive rocks of the North Shore Volcanic Group produced during that same geologic event. These formations are part of the Superior Upland physiographic region of the United States, which is associated with the Laurentian Upland of the Canadian Shield, the core of the North American Craton. Location The Duluth Complex includes much of Minnesota's Arrowhead Region north of Lake Superior. From the west near Duluth, Minnesota, it arcs north and northeast to about 48° north latitude south of Knife Lake, proceeds east at that latitude some five to twenty kilometers distant from an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoproterozoic
The Paleoproterozoic Era (;, also spelled Palaeoproterozoic), spanning the time period from (2.5–1.6 Ga), is the first of the three sub-divisions (eras) of the Proterozoic Eon. The Paleoproterozoic is also the longest era of the Earth's geological history. It was during this era that the continents first stabilized. Paleontological evidence suggests that the Earth's rotational rate ~1.8 billion years ago equated to 20-hour days, implying a total of ~450 days per year. Atmosphere Before the enormous increase in atmospheric oxygen, almost all existing lifeforms were anaerobic organisms whose metabolism was based on a form of cellular respiration that did not require oxygen. Free oxygen in large amounts is toxic to most anaerobic organisms. Consequently, most died when the atmospheric free oxygen levels soared in an extinction event called the Great Oxidation Event, which brought atmospheric oxygen levels to up to 10% of their current level. The only creatures that survi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Twin Metals Mine
Twin Metals LLC is seeking approval to create and operate a copper sulfide mine near Ely, Minnesota, on Superior National Forest land. There has been significant opposition to the proposed mine, most notably because of its proximity to the Boundary Waters Canoe Area Wilderness, location within a watershed that drains into the BWCA, and the air, water, light and noise pollution and traffic effects of converting a forested area bordering the BWCA into a substantial industrial mining facility. Twin Metals is a subsidiary of the Chilean conglomerate Antofagasta, which is controlled by billionaire Andrónico Luksic. The original lease is a 1966 lease to the International Nickel Corporation. The leases were terminated under the Obama administration but renewed under the Trump administration. Critics have objected to and filed lawsuits against various aspects of the lease renewal and regulatory processes. In March 2021, President Joe Biden announced that the Interior and Agriculture depart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Range Resources And Rehabilitation Board
The Minnesota Department of Iron Range Resources and Rehabilitation (IRRRB) is an economic development agency of the State of Minnesota, designed to advance growth on Minnesota's Iron Range. Founded in 1941, the board is tasked with using proceeds from taconite mining to spur broader development in the region. The mission of IRRRB is to "invest in resources to foster vibrant growth and economic prosperity in northeastern Minnesota by enhancing livable communities, maximizing collaborations and partnerships and strengthen businesses and worker education. The agency provides vital funding, including low or no interest loans and grants for businesses relocating or expanding in the region. Additionally, a variety of grants are available to local units of government, education institutions, and nonprofits that promote workforce development and sustainable communities." The board is headquartered in Eveleth, Minnesota. The board's commissioner is appointed by the sitting governor and se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crow Wing County, Minnesota
Crow Wing County is a county in the East Central part of the U.S. state of Minnesota. As of the 2020 census, the population was 66,123. Its county seat is Brainerd. The county was formed in 1857, and was organized in 1870. Crow Wing County is included in the Brainerd, MN Micropolitan Statistical Area. History This area was long occupied by the Ojibwe people, also known as Chippewa. In addition, numerous Dakota people lived in central and southern Minnesota before European settlement. European Americans established a trading post by 1837 in this area, on the east side of the Mississippi River opposite the mouth of the Crow Wing River. The post (named Crow Wing) soon became a center of trading with the region's Native Americans, with a general-supply store that served the area. By 1866, the village contained about 600 whites and Chippewa; it was a major population center. The territorial government enacted the county's creation on May 23, 1857, and named Crow Wing the county ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 total area. Its southern and western border with the United States, stretching , is the world's longest binational land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Indigenous peoples have continuously inhabited what is now Canada for thousands of years. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast. As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gunflint Range
The Gunflint Range is an iron ore deposit in northern Minnesota in the United States and Northwestern Ontario, Canada. The range extends from the extreme northern portion of Cook County, Minnesota into the Thunder Bay District, Ontario. The Gunflint Iron Formation is a continuation of the Mesabi Range to the southwest. The two have been separated by the intrusion of the Duluth Gabbro complex. The iron deposit is a banded iron formation of the Early Proterozoic Animikie Group. The Gunflint Iron Formation is overlain by "brecciated and complexly deformed iron formations", which in turn is overlain by ejecta from the " Sudbury meteorite impact event." This Sudbury Impact Layer is overlain by the Rove Formation. Stromatolite structures are evident within the Gunflint Iron Formation. The cherts of the Gunflint (the Gunflint Chert) are noted for containing Precambrian microfossils. See also *Midcontinent Rift System * Paulson Mine * Cuyuna Range *Vermilion Range (Minnesota) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermilion Range (Minnesota)
The Vermilion Range exists between Tower, Minnesota and Ely, Minnesota, and contains significant deposits of iron ore. Together with the Mesabi and Cuyuna Ranges, these three constitute the Iron Ranges of northern Minnesota. While the Mesabi Range had iron ore close enough to the surface to enable pit mining, mines had to be dug deep underground to reach the ore of the Vermilion and Cuyuna ranges. The Soudan mine was nearly 1/2 mile underground and required blasting of Precambrian sedimentary bedrock.Jackson, Judy"Notes from Underground" ''Ferminews'', July 19, 2002. The banded iron formation in the range consists of a "interbedded sequence" of chert, magnetite and hematite. Eleven mines operated in the range, with five in the Ely area. The Ely Trough, a synclinal fold, produced 70 million metric tons from the Chandler, Pioneer, Zenith, Sibley and Savoy mines. The largest mine in the range, Soudan, was closed in 1962, and the last mine in the Ely area closed in 1964. Despite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minnesota Historical Society
The Minnesota Historical Society (MNHS) is a nonprofit educational and cultural institution dedicated to preserving the history of the U.S. state of Minnesota. It was founded by the territorial legislature in 1849, almost a decade before statehood. The Society is named in the Minnesota Constitution. It is headquartered in the Minnesota History Center in downtown Saint Paul. Although its focus is on Minnesota history it is not constrained by it. Its work on the North American fur trade has been recognized in Canada as well. MNHS holds a collection of nearly 550,000 books, 37,000 maps, 250,000 photographs, 225,000 historical artifacts, 950,000 archaeological items, of manuscripts, of government records, 5,500 paintings, prints and drawings; and 1,300 moving image items. ''MNopedia: The Minnesota Encyclopedia'', is since 2011 an online "resource for reliable information about significant people, places, events, and things in Minnesota history", that is funded through a Legacy A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology
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] |
