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Sibley Peninsula
The Sibley Peninsula is a and peninsula in Ontario, Canada, on Lake Superior. It projects into the lake from Superior's north shore, and separates Thunder Bay to the west from Black Bay to the east.''Sleeping Giant Background Information'', 3.2 Earth Science, Topography, pp. 11. Sleeping Giant Provincial Park occupies most of the peninsula, while the actual Sleeping Giant rock formation, which resembles a human figure lying on its back, forms the southernmost extension of the peninsula. Twenty native fish species are known from lakes within the park. Also on the peninsula are the Thunder Cape Bird Observatory, at its southern tip, and the small town of Silver Islet. Highway 587 runs along the peninsula from Highway 17 to Silver Islet. The peninsula was named after Alexander H. Sibley, president of the Silver Islet Mining Company that developed a mine there. Geology The peninsula can be separated into two physiographic areas—highlands and lowlands. The highlands do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleeping Giant PP
Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity and interactions with the surrounding environment. While sleep differs from wakefulness in terms of the ability to react to stimuli, it still involves active brain patterns, making it more reactive than a coma or disorders of consciousness. Sleep occurs in repeating periods, during which the body alternates between two distinct modes: rapid eye movement sleep (REM) and non-REM sleep. Although REM stands for "rapid eye movement", this mode of sleep has many other aspects, including virtual paralysis of the body. Dreams are a succession of images, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. During sleep, most of the body's systems are in an anabolic state, helping to restore the immune, nervous, skeletal, and muscular s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Highland (geography)
Highlands or uplands are areas of high elevation such as a mountainous region, elevated mountainous plateau or high hills. Generally, ''upland'' refers to a range of hills, typically from up to , while ''highland'' is usually reserved for ranges of low mountains. However, the two terms are interchangeable and also include regions that are transitional between hilly and mountainous terrain. Highlands internationally Probably the best-known area officially or unofficially referred to as ''highlands'' in the Anglosphere is the Scottish Highlands in northern Scotland, the mountainous region north and west of the Highland Boundary Fault. The Highland council area is a local government area in the Scottish Highlands and Britain's largest local government area. Other highland or upland areas reaching 400 m or higher in the United Kingdom include the Southern Uplands in Scotland, the Pennines, North York Moors, Dartmoor and Exmoor in England, and the Cambrian Mountains in Wales. Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Bay Peninsula
Black Bay Peninsula is a volcanic peninsula in Unorganized Thunder Bay District in Northwestern Ontario, Canada, located on the North Shore of Lake Superior. Shows the extent of the peninsula highlighted on a map. It separates Black Bay and Nipigon Bay and consists of over 300 flood basalt lava flows. Porphyry Island Porphyry Island is an island in Unorganized Thunder Bay District in northwestern Ontario, Canada. It is the last island in a chain stretching south west of the Black Bay Peninsula in Lake Superior. It is located about from Edward Island Pro ..., an island entirely encompassed within Porphyry Island Provincial Park, lies off the tip of the peninsula. A portion of the peninsula has been set aside as the Black Bay Peninsula Enhanced Management Area. References Other map sources: * * Peninsulas of Ontario Landforms of Thunder Bay District Volcanism of Ontario Precambrian volcanism Flood basalts {{NorthernOntario-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woodland Period
In the classification of :category:Archaeological cultures of North America, archaeological cultures of North America, the Woodland period of North American pre-Columbian cultures spanned a period from roughly 1000 BC to European contact in the eastern part of North America, with some archaeologists distinguishing the Mississippian period, from 1000 AD to European contact as a separate period. The term "Woodland Period" was introduced in the 1930s as a generic term for prehistoric, prehistoric sites falling between the Archaic period in the Americas, Archaic hunter-gatherers and the agriculturalist Mississippian cultures. The Eastern Woodlands cultural region covers what is now eastern Canada south of the Subarctic region, the Eastern United States, along to the Gulf of Mexico. This period is variously considered a developmental stage, a time period, a suite of technological adaptations or "traits", and a "family tree" of cultures related to earlier Archaic cultures. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaic Period In The Americas
In the classification of the archaeological cultures of North America, the Archaic period in North America, taken to last from around 8000 to 1000 BC in the sequence of North American pre-Columbian cultural stages, is a period defined by the ''archaic stage'' of cultural development. The Archaic stage is characterized by subsistence economies supported through the exploitation of nuts, seeds, and shellfish. As its ending is defined by the adoption of sedentary farming, this date can vary significantly across the Americas. The rest of the Americas also have an Archaic Period. Classifications This classification system was first proposed by Gordon Willey and Philip Phillips in the widely accepted 1958 book ''Method and Theory in American Archaeology''. In the organization of the system, the Archaic period followed the Lithic stage and is superseded by the Formative stage. # The Lithic stage # The Archaic stage # The Formative stage # The Classic stage # The Post-Cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleo-Indians
Paleo-Indians were the first peoples who entered and subsequently inhabited the Americas towards the end of the Late Pleistocene period. The prefix ''paleo-'' comes from . The term ''Paleo-Indians'' applies specifically to the lithic period in the Western Hemisphere and is distinct from the term ''Paleolithic''.''Paleolithic'' specifically refers to the period between million years ago and the end of the Pleistocene in the Eastern Hemisphere. It is not used in New World archaeology. Traditional theories suggest that big-animal hunters crossed the Bering Strait from North Asia into the Americas over a land bridge ( Beringia). This bridge existed from 45,000 to 12,000 BCE (47,000–14,000 BP). Small isolated groups of hunter-gatherers migrated alongside herds of large herbivores far into Alaska. From BCE ( BP), ice-free corridors developed along the Pacific coast and valleys of North America. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuesta
A cuesta () is a hill or ridge with a gentle slope on one side, and a steep slope on the other. In geology, the term is more specifically applied to a ridge where a harder sedimentary rock overlies a softer layer, the whole being tilted somewhat from the horizontal. This results in a long and gentle backslope called a dip slope that conforms with the dip of resistant strata, called caprock. Where erosion has exposed the frontslope of this, a steep slope or escarpment occurs. The resulting terrain may be called scarpland. Definition In general usage, a cuesta is a hill or ridge with a gentle slope (backslope) on one side, and a steep slope (frontslope) on the other. The word is from Spanish: "flank or slope of a hill; hill, mount, sloping ground". In geology and geomorphology, cuesta refers specifically to an asymmetric ridge with a long and gentle backslope called a dip slope that conforms with the dip of a resistant stratum or strata, called caprock. The outcrop of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rocks
Sedimentary rocks are types of rock formed by the cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or deposited at Earth's surface. Sedimentation is any process that causes these particles to settle in place. Geological detritus originates from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus is formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies ( marine snow). Sedimentation may also occur when dissolved minerals precipitate from water solution. The sedimentary rock cover of the continents of the Earth's crust is extensive (73% of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sill (geology)
In geology, a sill is a tabular sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava or tuff, or along the direction of foliation in metamorphic rock. A sill is a ''concordant intrusive sheet'', meaning that it does not cut across preexisting rock beds. Stacking of sills builds a sill complex. and a large magma chamber at high magma flux. In contrast, a dike is a discordant intrusive sheet, which does cut across older rocks. Formation Sills are fed by dikes, except in unusual locations where they form in nearly vertical beds attached directly to a magma source. The rocks must be brittle and fracture to create the planes along which the magma intrudes the parent rock bodies, whether this occurs along preexisting planes between sedimentary or volcanic beds or weakened planes related to foliation in metamorphic rock. These planes or weakened areas allow the intrusion of a thin sheet-like body of magma paralleling the existi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dike (geology)
In geology, a dike or dyke is a sheet of rock that is formed in a fracture of a pre-existing rock body. Dikes can be either magmatic or 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) reaches the surface. They are studied by geologists for the clues they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabase
Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grained to aphanitic chilled margins which may contain tachylite (dark mafic glass). ''Diabase'' is the preferred name in North America, while ''dolerite'' is the preferred name in the rest of the English-speaking world, where sometimes the name ''diabase'' refers to altered dolerites and basalts. Some geologists prefer to avoid confusion by using the name ''microgabbro''. The name ''diabase'' comes from the French , and ultimately from the Greek 'act of crossing over, transition', whereas the name ''dolerite'' comes from the French , from the Greek 'deceitful, deceptive', because it was easily confused with diorite. Petrography Diabase normally has a fine but visible texture of euhedral lath-shaped plagioclase crystals (62%) set i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lowland
Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a plain that are conditionally categorized by their elevation above the sea level. Lowlands are usually no higher than , while uplands are somewhere around to . On unusual occasions, certain lowlands such as the Caspian Depression lie below sea level. Uplands areas tend to spike into valleys and mountains, forming mountain ranges while lowland areas tend to be uniformly flat, although both can vary such as the Mongolian Plateau. Upland habitats are cold, clear and rocky whose rivers are fast-flowing in mountainous areas; lowland habitats are warm with slow-flowing rivers found in relatively flat lowland areas, with water that is frequently colored by sediment and organic matter. These classifications overlap with the geological definitions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
