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Taconic Orogeny
The Taconic orogeny was a mountain building period that ended 440 million years ago (Ma) and affected most of modern-day New England. A great mountain chain formed from eastern Canada down through what is now the Piedmont of the east coast of the United States. As the mountain chain eroded in the Silurian and Devonian periods, sediment spread throughout the present-day Appalachians and midcontinental North America. New England and Canada Beginning in Cambrian time, about 550 Ma, the Iapetus Ocean began to close. The weight of accumulating sediments, in addition to compressional forces in the crust, forced the eastern edge of the North American continent to fold gradually downward. In this manner, shallow-water carbonate deposition that had persisted on the continental shelf margin through late Cambrian into early Ordovician time, gave way to fine-grained clastic deposition and deeper water conditions during the middle Ordovician. In this period a convergent plate boundary deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydration Reaction
In chemistry, a dehydration reaction is a chemical reaction that involves the loss of an H2O from the reacting molecule(s) or ion(s). This reaction results in the release of the H2O as water. When the reaction involves the coupling of two molecules into a single molecule it is referred to as a condensation reaction. Dehydration reactions are common processes in the manufacture of chemical compounds as well as naturally occurring within living organisms. The reverse of a dehydration reaction is called a hydration reaction. The reverse of a condensation reaction yielding water is called hydrolysis. Condensation reactions occurring in living organisms Condensation dehydration reactions are fundamental to the existence of life as this type of reaction produces proteins from amino acids, DNA and RNA from nucleotides, fats from fatty acids, and polysaccharides (eg. cellulose, starch, sugar, lactose) from monosaccharides (eg. glucose and fructose). The formation of the pyrophosphat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Bronx
The Bronx ( ) is the northernmost of the five Boroughs of New York City, boroughs of New York City, coextensive with Bronx County, in the U.S. state of New York (state), New York. It shares a land border with Westchester County, New York, Westchester County to its north; to its south and west, the New York City borough of Manhattan is across the Harlem River; and to its south and east is the borough of Queens, across the East River. The Bronx, the only New York City borough not primarily located on an island, has a land area of and a population of 1,472,654 at the 2020 United States census, 2020 census. It has the fourth-largest area, fourth-highest population, and third-highest population density of the boroughs.New York State Department of Health''Population, Land Area, and Population Density by County, New York State – 2010'' retrieved on August 8, 2015. The Bronx is divided by the Bronx River into a hillier section in the West Bronx, west, and a flatter East Bronx, easte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York City
New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive with a respective county. The city is the geographical and demographic center of both the Northeast megalopolis and the New York metropolitan area, the largest metropolitan area in the United States by both population and urban area. New York is a global center of finance and commerce, culture, technology, entertainment and media, academics, and scientific output, the arts and fashion, and, as home to the headquarters of the United Nations, international diplomacy. With an estimated population in 2024 of 8,478,072 distributed over , the city is the most densely populated major city in the United States. New York City has more than double the population of Los Angeles, the nation's second-most populous city. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connecticut
Connecticut ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the south. Its capital is Hartford, Connecticut, Hartford, and its most populous city is Bridgeport, Connecticut, Bridgeport. Connecticut lies between the major hubs of New York City and Boston along the Northeast megalopolis, Northeast Corridor, where the New York metropolitan area, New York-Newark Combined Statistical Area, which includes four of Connecticut's seven largest cities, extends into the southwestern part of the state. Connecticut is the List of U.S. states and territories by area, third-smallest state by area after Rhode Island and Delaware, and the List of U.S. states and territories by population, 29th most populous with more than 3.6 million residents as of 2024, ranking it fourth among the List of states and territories of the Unite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture (geology)
In structural geology, a suture is a joining along a major fault zone, of separate terranes, tectonic units that have different plate tectonic, metamorphic and paleogeographic histories. The suture is often represented on the surface by an orogen or mountain range. Overview In plate tectonics, sutures are the remains of subduction zones, and the terranes that are joined are interpreted as fragments of different palaeocontinents or tectonic plates. Outcrops of sutures can vary in width from a few hundred meters to a couple of kilometers. They can be networks of mylonitic shear zones or brittle fault zones, but are usually both. Sutures are usually associated with igneous intrusions and tectonic lenses with varying kinds of lithologies from plutonic rocks to ophiolitic fragments. An example from Great Britain is the Iapetus Suture which, though now concealed beneath younger rocks, has been determined by geophysical means to run along a line roughly parallel wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cameron's Line
Cameron's Line is an Ordovician suture fault in the northeast United States that formed as part of the continental collision known as the Taconic orogeny around 450 million years ago. Named after geologist Eugene N. Cameron, who first published a description in the 1950s, it ties together the North American continental craton, the prehistoric Taconic island volcanic arc, and the bottom of the ancient Iapetus Ocean. Cameron himself credited his colleague William M. Agar with the initial discovery. Location Cameron's Line winds southward out of New England through western Connecticut. It has been identified in western Connecticut near Ridgefield before it heads into Westchester County, New York, then the Bronx, along the East River in Manhattan, through New York Bay, Staten Island, and into New Jersey. Geology The basement rocks of the Manhattan Formation located on the western side of Cameron's Line are metamorphosed sedimentary rocks and can be thought of as the remnan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphism
Metamorphism is the transformation of existing Rock (geology), rock (the protolith) to rock with a different mineral composition or Texture (geology), texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chemically active fluids, but the rock remains mostly solid during the transformation. Metamorphism is distinct from weathering or diagenesis, which are changes that take place at or just beneath Earth's surface. Various forms of metamorphism exist, including Regional metamorphism, regional, Contact metamorphism, contact, Hydrothermal metamorphism, hydrothermal, Shock metamorphism, shock, and Dynamic metamorphism, dynamic metamorphism. These differ in the characteristic temperatures, pressures, and rate at which they take place and in the extent to which reactive fluids are involved. Metamorphism occurring at increasing pressure and temperature conditions is known as ''prograde metamorphism'', while decreasin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology), crust result from the action of Plate tectonics, plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction, subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the Plane (geometry), plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geological maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fold (geology)
In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary rock, sedimentary stratum, strata, that are bent or curved (''"folded"'') during permanent deformation (engineering), deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur as single isolated folds or in periodic sets (known as ''fold trains''). wikt:synsedimentary, Synsedimentary folds are those formed during sedimentary deposition. Folds form under varied conditions of stress (physics), stress, pore pressure, and temperature gradient, as evidenced by their presence in soft sedimentary rock, sediments, the full spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogeny, orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Rock
Igneous rock ( ), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava. The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms, orogens, basins, large igneous provinces, extended crust and oceanic crust. Geological significance Igneous and metamorphic rocks make up 90–95% of the top of the Earth's crust by volume. Igneous rock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), 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 wasting, 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 aqueous solution, water solution. The sedimentary rock cover of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
