The Hadean is a geologic eon of the Earth pre-dating the Archean. It began with the formation of the Earth about 4.6 billion years ago and ended, as defined by the ICS, 4 billion years ago. As of 2016, the ICS describes its status as "informal". Geologist Preston Cloud coined the term in 1972 to label the period before the earliest-known rocks on Earth. W. Brian Harland coined an synonymous term, the "Priscoan period", from priscus, the Latin word for "ancient". Other, older texts refer to the eon as the Pre-Archean. "Hadean" describes the hellish conditions prevailing on Earth: the planet had just formed and was still hot owing to its recent accretion, the abundance of short-lived radioactive elements, frequent collisions with other Solar System bodies. Since few geological traces of this eon remain on Earth, there is no official subdivision. However, the Lunar geologic timescale embraces several major divisions relating to the Hadean, so these are sometimes used in an informal sense to refer to the same periods of time on Earth.
The Lunar divisions are: Pre-Nectarian, from the formation of the Moon's crust up to about 3,920 million years ago. Nectarian ranging from 3,920 million years ago up to about 3,850 million years ago, in a time when the Late Heavy Bombardment, according to that theory, was in a stage of decline. In 2010, an alternative scale was proposed that includes the addition of the Chaotian and Prenephelean Eons preceding the Hadean, divides the Hadean into three eras with two periods each; the Paleohadean era consists of the Jacobian periods. The Mesohadean is divided into the Procrustean periods; the Neohadean is divided into the Promethean periods. As of February 2017, this has not been adopted by the IUGS. In the last decades of the 20th century geologists identified a few Hadean rocks from western Greenland, northwestern Canada, Western Australia. In 2015, traces of carbon minerals interpreted as "remains of biotic life" were found in 4.1-billion-year-old rocks in Western Australia. The oldest dated zircon crystals, enclosed in a metamorphosed sandstone conglomerate in the Jack Hills of the Narryer Gneiss Terrane of Western Australia, date to 4.404 ± 0.008 Ga.
This zircon is a slight outlier, with the oldest consistently-dated zircon falling closer to 4.35 Ga—around 200 million years after the hypothesized time of the Earth's formation. In many other areas, xenocryst Hadean zircons enclosed in older rocks indicate that younger rocks have formed on older terranes and have incorporated some of the older material. One example occurs in the Guiana shield from the Iwokrama Formation of southern Guyana where zircon cores have been dated at 4.22 Ga. A sizable quantity of water would have been in the material. Water molecules would have escaped Earth's gravity more when it was less massive during its formation. Hydrogen and helium are expected to continually escape due to atmospheric escape. Part of the ancient planet is theorized to have been disrupted by the impact that created the Moon, which should have caused melting of one or two large regions of the Earth. Earth's present composition suggests that there was not complete remelting as it is difficult to melt and mix huge rock masses.
However, a fair fraction of material should have been vaporized by this impact, creating a rock vapor atmosphere around the young planet. The rock vapor would have condensed within two thousand years, leaving behind hot volatiles which resulted in a heavy CO2 atmosphere with hydrogen and water vapor. Liquid water oceans existed despite the surface temperature of 230 °C because at an atmospheric pressure of above 27 atmospheres, caused by the heavy CO2 atmosphere, water is still liquid; as cooling continued and dissolving in ocean water removed most CO2 from the atmosphere but levels oscillated wildly as new surface and mantle cycles appeared. Studies of zircons have found that liquid water must have existed as long ago as 4.4 billion years ago soon after the formation of the Earth. This requires the presence of an atmosphere; the cool early Earth theory covers a range from about 4.4 to about 4.1 billion years. A September 2008 study of zircons found that Australian Hadean rock holds minerals pointing to the existence of plate tectonics as early as 4 billion years.
If this is true, the time when Earth finished its transition from having a hot, molten surface and atmosphere full of carbon dioxide, to being much like it is today, can be dated to about 4.0 billion years ago. The actions of plate tectonics and the oceans trapped vast amounts of carbon dioxide, thereby reducing the greenhouse effect and leading to a much cooler surface temperature and the formation of solid rock, even life. Chaotian – Proposed era of, or eon preceding, the Hadean eon Formation and evolution of the Solar System – Formation of the Solar System by gravitational collapse of a molecular cloud and subsequent geological history Hadean zircon – The oldest-surviving crustal material from the Earth's earliest geological time period History of Earth – The development of planet Earth from its formation to the present day – the first sections describe the formation of the Earth Oldest dated rocks – Includes rocks over 4 billion years old from the Hadean Eon Precambrian – The earliest part of Earth's history Timeline of natural history Hopkins, Michelle.
The Precambrian is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic eon, named after Cambria, the Latinised name for Wales, where rocks from this age were first studied; the Precambrian accounts for 88% of the Earth's geologic time. The Precambrian is an informal unit of geologic time, subdivided into three eons of the geologic time scale, it spans from the formation of Earth about 4.6 billion years ago to the beginning of the Cambrian Period, about 541 million years ago, when hard-shelled creatures first appeared in abundance. Little is known about the Precambrian, despite it making up seven-eighths of the Earth's history, what is known has been discovered from the 1960s onwards; the Precambrian fossil record is poorer than that of the succeeding Phanerozoic, fossils from the Precambrian are of limited biostratigraphic use. This is because many Precambrian rocks have been metamorphosed, obscuring their origins, while others have been destroyed by erosion, or remain buried beneath Phanerozoic strata.
It is thought that the Earth coalesced from material in orbit around the Sun at 4,543 Ma, may have been struck by a large planetesimal shortly after it formed, splitting off material that formed the Moon. A stable crust was in place by 4,433 Ma, since zircon crystals from Western Australia have been dated at 4,404 ± 8 Ma; the term "Precambrian" is recognized by the International Commission on Stratigraphy as the only "supereon" in geologic time. "Precambrian" is still used by geologists and paleontologists for general discussions not requiring the more specific eon names. As of 2010, the United States Geological Survey considers the term informal, lacking a stratigraphic rank. A specific date for the origin of life has not been determined. Carbon found in 3.8 billion-year-old rocks from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have been found in Western Australia. Probable fossils 100 million years older have been found in the same area.
However, there is evidence. There is a solid record of bacterial life throughout the remainder of the Precambrian. Excluding a few contested reports of much older forms from North America and India, the first complex multicellular life forms seem to have appeared at 1500 Ma, in the Mesoproterozoic era of the Proterozoic eon. Fossil evidence from the Ediacaran period of such complex life comes from the Lantian formation, at least 580 million years ago. A diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma; these are referred to as Vendian biota. Hard-shelled creatures appeared toward the end of that time span, marking the beginning of the Phanerozoic eon. By the middle of the following Cambrian period, a diverse fauna is recorded in the Burgess Shale, including some which may represent stem groups of modern taxa; the increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life. While land seems to have been devoid of plants and animals and other microbes formed prokaryotic mats that covered terrestrial areas.
Tracks from an animal with leg like appendages have been found in what was mud 551 million years ago. Evidence of the details of plate motions and other tectonic activity in the Precambrian has been poorly preserved, it is believed that small proto-continents existed prior to 4280 Ma, that most of the Earth's landmasses collected into a single supercontinent around 1130 Ma. The supercontinent, known as Rodinia, broke up around 750 Ma. A number of glacial periods have been identified going as far back as the Huronian epoch 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a "Snowball Earth"; the atmosphere of the early Earth is not well understood. Most geologists believe it was composed of nitrogen, carbon dioxide, other inert gases, was lacking in free oxygen. There is, evidence that an oxygen-rich atmosphere existed since the early Archean. At present, it is still believed that molecular oxygen was not a significant fraction of Earth's atmosphere until after photosynthetic life forms evolved and began to produce it in large quantities as a byproduct of their metabolism.
This radical shift from a chemically inert to an oxidizing atmosphere caused an ecological crisis, sometimes called the oxygen catastrophe. At first, oxygen would have combined with other elements in Earth's crust iron, removing it from the atmosphere. After the supply of oxidizable surfaces ran out, oxygen would have begun to accumulate in the atmosphere, the modern high-oxygen atmosphere would have developed. Evidence for this lies in older rocks that contain massive banded iron formations that were laid down as iron oxides. A terminology has evolved covering the early years of the Earth's existence, as radiometric dating has allowed real dates to be assigned to specific formations and features; the Precambrian is divided into
The Northwest Territories is a federal territory of Canada. At a land area of 1,144,000 km2 and a 2016 census population of 41,786, it is the second-largest and the most populous of the three territories in Northern Canada, its estimated population as of 2018 is 44,445. Yellowknife became the territorial capital in 1967, following recommendations by the Carrothers Commission; the Northwest Territories, a portion of the old North-Western Territory, entered the Canadian Confederation on July 15, 1870, but the current borders were formed on April 1, 1999, when the territory was subdivided to create Nunavut to the east, via the Nunavut Act and the Nunavut Land Claims Agreement. While Nunavut is Arctic tundra, the Northwest Territories has a warmer climate and is both boreal forest, tundra, its most northern regions form part of the Canadian Arctic Archipelago; the Northwest Territories is bordered by Canada's two other territories, Nunavut to the east and Yukon to the west, by the provinces of British Columbia and Saskatchewan to the south.
The name is descriptive, adopted by the British government during the colonial era to indicate where it lay in relation to Rupert's Land. It is shortened from North-Western Territory. In Inuktitut, the Northwest Territories are referred to as ᓄᓇᑦᓯᐊᖅ, "beautiful land."There was some discussion of changing the name of the Northwest Territories after the splitting off of Nunavut to a term from an Aboriginal language. One proposal was "Denendeh", among others. One of the most popular proposals for a new name – one to name the territory "Bob" – began as a prank, but for a while it was at or near the top in the public-opinion polls. In the end, a poll conducted prior to division showed that strong support remained to keep the name "Northwest Territories"; this name arguably became more appropriate following division than it had been when the territories extended far into Canada's north-central and northeastern areas. Located in northern Canada, the territory borders Canada's two other territories, Yukon to the west and Nunavut to the east, three provinces: British Columbia to the southwest, Alberta and Saskatchewan to the south.
It meets Manitoba at a quadripoint to the extreme southeast, though surveys have not been completed. It has a land area of 1,183,085 km2. Geographical features include Great Bear Lake, the largest lake within Canada, Great Slave Lake, the deepest body of water in North America at 614 m, as well as the Mackenzie River and the canyons of the Nahanni National Park Reserve, a national park and UNESCO World Heritage Site. Territorial islands in the Canadian Arctic Archipelago include Banks Island, Borden Island, Prince Patrick Island, parts of Victoria Island and Melville Island, its highest point is Mount Nirvana near the border with Yukon at an elevation of 2,773 m. The Northwest Territories extends for more than 1,300,000 km2 and has a large climate variant from south to north; the southern part of the territory has a subarctic climate, while the islands and northern coast have a polar climate. Summers in the north are short and cool, with daytime highs of 14-17 Celsius, lows of 1-5 Celsius. Winters are long and harsh, daytime highs in the mid −20 °C and lows around −40 °C.
Extremes are common with summer highs in the south reaching 36 °C and lows reaching into the negatives. In winter in the south, it is not uncommon for the temperatures to reach −40 °C, but they can reach the low teens during the day. In the north, temperatures can reach highs of 30 °C, lows can reach into the low negatives. In winter in the north it is not uncommon for the temperatures to reach −50 °C but they can reach the single digits during the day. Thunderstorms are not rare in the south. In the north they are rare, but do occur. Tornadoes are rare but have happened with the most notable one happening just outside Yellowknife that destroyed a communications tower; the Territory has a dry climate due to the mountains in the west. About half of the territory is above the tree line. There are not many trees in the north islands; the present-day territory came under government authority in July 1870, after the Hudson's Bay Company transferred Rupert's Land and the North-Western Territory to the British Crown, which subsequently transferred them to Canada, giving it the name the North-west Territories.
This immense region comprised all of today's Canada except that, encompassed within the early signers of Canadian Confederation, that is, British Columbia, early forms of present-day Ontario and Quebec, the Maritimes, the Labrador coast, the Arctic Islands, except the southern half of Baffin Island. The first residential school opened in 1867 in Fort Resolution, followed by several others in regions across the territory, thus contributing to the Northwest Territories reaching the highest percentage of students in residential schools of any area in Canada. After the 1870 transfer, some of the North-west Territories was whittled away; the province of Manitoba was created on July 15, 1870, at first a small square area around Winnipeg
Ontario is one of the 13 provinces and territories of Canada and is located in east-central Canada. It is Canada's most populous province accounting for 38.3 percent of the country's population, is the second-largest province in total area. Ontario is fourth-largest jurisdiction in total area when the territories of the Northwest Territories and Nunavut are included, it is home to the nation's capital city and the nation's most populous city, Ontario's provincial capital. Ontario is bordered by the province of Manitoba to the west, Hudson Bay and James Bay to the north, Quebec to the east and northeast, to the south by the U. S. states of Minnesota, Ohio and New York. All of Ontario's 2,700 km border with the United States follows inland waterways: from the west at Lake of the Woods, eastward along the major rivers and lakes of the Great Lakes/Saint Lawrence River drainage system; these are the Rainy River, the Pigeon River, Lake Superior, the St. Marys River, Lake Huron, the St. Clair River, Lake St. Clair, the Detroit River, Lake Erie, the Niagara River, Lake Ontario and along the St. Lawrence River from Kingston, Ontario, to the Quebec boundary just east of Cornwall, Ontario.
There is only about 1 km of land border made up of portages including Height of Land Portage on the Minnesota border. Ontario is sometimes conceptually divided into Northern Ontario and Southern Ontario; the great majority of Ontario's population and arable land is in the south. In contrast, the larger, northern part of Ontario is sparsely populated with cold winters and heavy forestation; the province is named after Lake Ontario, a term thought to be derived from Ontarí:io, a Huron word meaning "great lake", or skanadario, which means "beautiful water" in the Iroquoian languages. Ontario has about 250,000 freshwater lakes; the province consists of three main geographical regions: The thinly populated Canadian Shield in the northwestern and central portions, which comprises over half the land area of Ontario. Although this area does not support agriculture, it is rich in minerals and in part covered by the Central and Midwestern Canadian Shield forests, studded with lakes and rivers. Northern Ontario is subdivided into two sub-regions: Northeastern Ontario.
The unpopulated Hudson Bay Lowlands in the extreme north and northeast swampy and sparsely forested. Southern Ontario, further sub-divided into four regions. Despite the absence of any mountainous terrain in the province, there are large areas of uplands within the Canadian Shield which traverses the province from northwest to southeast and above the Niagara Escarpment which crosses the south; the highest point is Ishpatina Ridge at 693 metres above sea level in Temagami, Northeastern Ontario. In the south, elevations of over 500 m are surpassed near Collingwood, above the Blue Mountains in the Dundalk Highlands and in hilltops near the Madawaska River in Renfrew County; the Carolinian forest zone covers most of the southwestern region of the province. The temperate and fertile Great Lakes-Saint Lawrence Valley in the south is part of the Eastern Great Lakes lowland forests ecoregion where the forest has now been replaced by agriculture and urban development. A well-known geographic feature is part of the Niagara Escarpment.
The Saint Lawrence Seaway allows navigation to and from the Atlantic Ocean as far inland as Thunder Bay in Northwestern Ontario. Northern Ontario occupies 87 percent of the surface area of the province. Point Pelee is a peninsula of Lake Erie in southwestern Ontario, the southernmost extent of Canada's mainland. Pelee Island and Middle Island in Lake Erie extend farther. All are south of 42°N – farther south than the northern border of California; the climate of Ontario varies by location. It is affected by three air sources: cold, arctic air from the north; the effects of these major air masses on temperature and precipitation depend on latitude, proximity to major bodies of water and to a small extent, terrain relief. In general, most of Ontario's climate is classified as humid continental. Ontario has three main climatic regions; the surrounding Great Lakes influence the climatic region of southern Ontario. During the fall and winter months, heat stored from the lakes is released, moderating the climate near the shores of the lakes.
This gives some parts of southern Ontario milder winters than mid-continental areas at lower latitudes. Parts of Southwestern Ontario have a moderate humid continental climate, similar to that of the inland Mid-Atlantic states and the Great Lakes portion of the Midwestern United States; the region has warm to cold winters. Annual precipitation is well distributed throughout the year. Most of this region lies in the lee of the Great Lakes. In December 2010, the snowbelt set a new record when it was h
Greenland is an autonomous constituent country of the Kingdom of Denmark between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for more than a millennium; the majority of its residents are Inuit, whose ancestors began migrating from the Canadian mainland in the 13th century settling across the island. Greenland is the world's largest island. Three-quarters of Greenland is covered by the only permanent ice sheet outside Antarctica. With a population of about 56,480, it is the least densely populated territory in the world. About a third of the population live in the capital and largest city; the Arctic Umiaq Line ferry acts as a lifeline for western Greenland, connecting the various cities and settlements. Greenland has been inhabited at intervals over at least the last 4,500 years by Arctic peoples whose forebears migrated there from what is now Canada.
Norsemen settled the uninhabited southern part of Greenland beginning in the 10th century, having settled Iceland to escape persecution from the King of Norway and his central government. These Norsemen would set sail from Greenland and Iceland, with Leif Erikson becoming the first known European to reach North America nearly 500 years before Columbus reached the Caribbean islands. Inuit peoples arrived in the 13th century. Though under continuous influence of Norway and Norwegians, Greenland was not formally under the Norwegian crown until 1262; the Norse colonies disappeared in the late 15th century when Norway was hit by the Black Death and entered a severe decline. Soon after their demise, beginning in 1499, the Portuguese explored and claimed the island, naming it Terra do Lavrador. In the early 18th century, Danish explorers reached Greenland again. To strengthen trading and power, Denmark–Norway affirmed sovereignty over the island; because of Norway's weak status, it lost sovereignty over Greenland in 1814 when the union was dissolved.
Greenland became Danish in 1814, was integrated in the Danish state in 1953 under the Constitution of Denmark. In 1973, Greenland joined the European Economic Community with Denmark. However, in a referendum in 1982, a majority of the population voted for Greenland to withdraw from the EEC, effected in 1985. Greenland contains the world's largest and most northerly national park, Northeast Greenland National Park. Established in 1974, expanded to its present size in 1988, it protects 972,001 square kilometres of the interior and northeastern coast of Greenland and is bigger than all but twenty-nine countries in the world. Greenland is divided into five municipalities – Sermersooq, Qeqertalik and Avannaata. Greenland does not have an independent seat at the United Nations. In 1979, Denmark granted home rule to Greenland, in 2008, Greenlanders voted in favor of the Self-Government Act, which transferred more power from the Danish government to the local Greenlandic government. Under the new structure, in effect since 21 June 2009, Greenland can assume responsibility for policing, judicial system, company law and auditing.
It retains control of monetary policy, providing an initial annual subsidy of DKK 3.4 billion, planned to diminish over time. Greenland expects to grow its economy based on increased income from the extraction of natural resources; the capital, held the 2016 Arctic Winter Games. At 70%, Greenland has one of the highest shares of renewable energy in the world coming from hydropower; the early Norse settlers named the island as Greenland. In the Icelandic sagas, the Norwegian-born Icelander Erik the Red was said to be exiled from Iceland for manslaughter. Along with his extended family and his thralls, he set out in ships to explore an icy land known to lie to the northwest. After finding a habitable area and settling there, he named it Grœnland in the hope that the pleasant name would attract settlers; the Saga of Erik the Red states: "In the summer, Erik left to settle in the country he had found, which he called Greenland, as he said people would be attracted there if it had a favorable name."The name of the country in the indigenous Greenlandic language is Kalaallit Nunaat.
The Kalaallit are the indigenous Greenlandic Inuit people. In prehistoric times, Greenland was home to several successive Paleo-Eskimo cultures known today through archaeological finds; the earliest entry of the Paleo-Eskimo into Greenland is thought to have occurred about 2500 BC. From around 2500 BC to 800 BC, southern and western Greenland were inhabited by the Saqqaq culture. Most finds of Saqqaq-period archaeological remains have been around Disko Bay, including the site of Saqqaq, after which the culture is named. From 2400 BC to 1300 BC, the Independence I culture existed in northern Greenland, it was a part of the Arctic small tool tradition. Towns, including Deltaterrassern
North American Cordillera
The North American Cordillera is the North American portion of the American Cordillera, a mountain chain along the western side of the Americas. The North American Cordillera covers an extensive area of mountain ranges, intermontane basins, plateaus in western North America, including much of the territory west of the Great Plains, it is sometimes called the Western Cordillera, the Western Cordillera of North America, or the Pacific Cordillera. The precise boundaries of this cordillera and its subregions, as well as the names of its various features, may differ depending on the definitions in each country or jurisdiction, depending on the scientific field; this cordillera extends from the U. S. state of Alaska to the southern border of Mexico. The North American Cordillera includes some of the highest peaks on the continent, its mountain ranges run north to south along three main belts: the Pacific Coast Ranges in the west, the Nevadan belt in the middle, the Laramide belt in the east. These three orogenic belts arose due to the engagement of tectonic plates which deformed the Earth's lithosphere.
For example, the Laramide orogeny changed the topography of the central Rocky Mountains and adjoining Laramide regions during the Late Cretaceous 80 million years ago. Prior to this time the Rocky Mountain region was occupied by a broad basin. Further topographical evolution occurred during the Eocene and Oligocene, but since that time the region has been stable. Speaking, it will be convenient here to consider these three belts going west to east, north to south. In Alaska, south of the Interior Plains area, is the Rocky Mountain System the Intermontane Basins and Ranges, in the southern part of the state are the Pacific Mountains and Valleys. In the Alaska panhandle, the mainland mountain ranges and offshore islands are extensions of respective ranges further south. In Canada, the North American Cordillera is divided into three physiographic regions: the western system, the interior system, the eastern system; the western system includes the Coast Mountains, the interior system includes the Columbia Mountains, the eastern system includes the Canadian Rockies.
At its midsection between San Francisco and Denver, the North American Cordillera is about 1,000 miles wide, its physiographic provinces at this midpoint are as follows, going from west to east: the Pacific Coast Ranges, the Central Valley, the Sierra Nevada, the Basin and Range Province, the Colorado Plateau, the Rocky Mountains. In the United States, another major feature of the Cordillera is the Columbia Plateau, located north of California between the Cascade Range —, a northern extension of the Sierra Nevada — and the Rocky Mountains. In Mexico, the Sierra Madre Occidental, the Sierra Madre Oriental further east, surround the Mexican Plateau. To the west of the Sierra Madre Occidental, the Peninsular Ranges border the Pacific Ocean, the Sierra Madre del Sur is the southern extension of the Peninsular Ranges. Sierra Madre means "Mother Range" in Spanish; the Nevadan belt runs down the middle of the North American Cordillera. Therefore, the intermontane areas of the cordillera can be divided up into the areas east of the Nevadan belt, those west of the Nevadan belt.
The Pacific Coast Ranges, comprising the Pacific Coast Belt, parallel the North American Pacific Coast, comprise several mountain systems. Along the British Columbia and Alaska coast, the mountains intermix with the sea in a complex maze of fjords, with thousands of islands. Off the Southern California coast the Channel Islands archipelago of the Santa Monica Mountains extends for 160 miles. In southern Alaska, the primary mountain ranges are the Alaska Range, Wrangell Mountains, Saint Elias Mountains, Kenai Mountains, Chugach Mountains, Talkeetna Mountains; the Yukon Ranges comprise the mountains in the southeastern part of the U. S. state of Alaska and most of the Yukon, Canada. This range has an area of 364,710 km2; the Coast Mountains run from the lower Fraser River and the Fraser Canyon northwestward, separating the Interior Plateau from the Pacific Ocean. Their coastal flank is characterized by an intense network of fjords and associated islands similar to the Norwegian coastline, while their inland side against the plateau they transition to the high plateau in dryland valleys notable for a series of large lakes similar to the alpine lakes of southern Switzerland, beginning in deep mountains and ending in flatland.
They are subdivided in three main groupings, the Pacific Ranges between the Fraser and Bella Coola, the Kitimat Ranges from there northwards to the Nass River and the Boundary Ranges from there to their terminus in the Yukon Territory at Champagne Pass and Chilkat Pass northwest of Haines, Alaska. The Saint Elias Mountains lie to their west and northwest, while the Yukon Ranges and Yukon Basin lie to their north. On the inland side of the Boundary Ranges are the Tahltan and Tagish Highlands and the Skeena Mountains, part of the Interior Mountains system, which extend southwards on the inland side of the Kitimat Ranges; the terrain of the main spine of the Coast Mountains is typified by heavy glaciation, including several large icefields of varying elevation. Of the three subdivisions, the Pacific Ranges are the highest and are crowned by Mount Waddington
Wisconsin is a U. S. state located in the Midwest and Great Lakes regions. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, Lake Superior to the north. Wisconsin is the 20th most populous; the state capital is Madison, its largest city is Milwaukee, located on the western shore of Lake Michigan. The state is divided into 72 counties. Wisconsin's geography is diverse, having been impacted by glaciers during the Ice Age with the exception of the Driftless Area; the Northern Highland and Western Upland along with a part of the Central Plain occupies the western part of the state, with lowlands stretching to the shore of Lake Michigan. Wisconsin is second to Michigan in the length of its Great Lakes coastline. During the 19th and early 20th centuries, a large number of European settlers entered the state, many of whom emigrated from Germany and Scandinavia. Like neighboring Minnesota, the state remains a center of German American and Scandinavian American culture.
Wisconsin is known as "America's Dairyland" because it is one of the nation's leading dairy producers famous for its cheese. Manufacturing, information technology, cranberries and tourism are major contributors to the state's economy; the word Wisconsin originates from the name given to the Wisconsin River by one of the Algonquian-speaking Native American groups living in the region at the time of European contact. French explorer Jacques Marquette was the first European to reach the Wisconsin River, arriving in 1673 and calling the river Meskousing in his journal. Subsequent French writers changed the spelling from Meskousing to Ouisconsin, over time this became the name for both the Wisconsin River and the surrounding lands. English speakers anglicized the spelling from Ouisconsin to Wisconsin when they began to arrive in large numbers during the early 19th century; the legislature of Wisconsin Territory made the current spelling official in 1845. The Algonquin word for Wisconsin and its original meaning have both grown obscure.
Interpretations vary. One leading theory holds that the name originated from the Miami word Meskonsing, meaning "it lies red", a reference to the setting of the Wisconsin River as it flows through the reddish sandstone of the Wisconsin Dells. Other theories include claims that the name originated from one of a variety of Ojibwa words meaning "red stone place", "where the waters gather", or "great rock". Wisconsin has been home to a wide variety of cultures over the past 14,000 years; the first people arrived around 10,000 BCE during the Wisconsin Glaciation. These early inhabitants, called Paleo-Indians, hunted now-extinct ice age animals such as the Boaz mastodon, a prehistoric mastodon skeleton unearthed along with spear points in southwest Wisconsin. After the ice age ended around 8000 BCE, people in the subsequent Archaic period lived by hunting and gathering food from wild plants. Agricultural societies emerged over the Woodland period between 1000 BCE to 1000 CE. Toward the end of this period, Wisconsin was the heartland of the "Effigy Mound culture", which built thousands of animal-shaped mounds across the landscape.
Between 1000 and 1500 CE, the Mississippian and Oneota cultures built substantial settlements including the fortified village at Aztalan in southeast Wisconsin. The Oneota may be the ancestors of the modern Ioway and Ho-Chunk tribes who shared the Wisconsin region with the Menominee at the time of European contact. Other Native American groups living in Wisconsin when Europeans first settled included the Ojibwa, Fox and Pottawatomie, who migrated to Wisconsin from the east between 1500 and 1700; the first European to visit what became Wisconsin was the French explorer Jean Nicolet. He canoed west from Georgian Bay through the Great Lakes in 1634, it is traditionally assumed that he came ashore near Green Bay at Red Banks. Pierre Radisson and Médard des Groseilliers visited Green Bay again in 1654–1666 and Chequamegon Bay in 1659–1660, where they traded for fur with local Native Americans. In 1673, Jacques Marquette and Louis Jolliet became the first to record a journey on the Fox-Wisconsin Waterway all the way to the Mississippi River near Prairie du Chien.
Frenchmen like Nicholas Perrot continued to ply the fur trade across Wisconsin through the 17th and 18th centuries, but the French made no permanent settlements in Wisconsin before Great Britain won control of the region following the French and Indian War in 1763. So, French traders continued to work in the region after the war, some, beginning with Charles de Langlade in 1764, settled in Wisconsin permanently, rather than returning to British-controlled Canada; the British took over Wisconsin during the French and Indian War, taking control of Green Bay in 1761 and gaining control of all of Wisconsin in 1763. Like the French, the British were interested in little but the fur trade. One notable event in the fur trading industry in Wisconsin occurred in 1791, when two free African Americans set up a fur trading post among the Menominee at present day Marinette; the first permanent settlers French Canadians, some Anglo-New Englanders and a few African American freedmen, arrived in Wisconsin while it was under British control.
Charles Michel de Langlade is recognized as the first settler, establishing a trading post at Green Bay in 1745, moving there permanently in 1764. Settlement began at Prairie du Chien around 1781; the French residents at the trading post in what is now Green Bay, referred to the t