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Lake Hitchcock
Lake Hitchcock was a glacial lake that formed approximately 15,000 years ago in the late Pleistocene epoch. After the Laurentide Ice Sheet retreated, glacial ice melt accumulated at the terminal moraine and blocked up the Connecticut River, creating the long, narrow lake. The lake existed for approximately 3,000 years, after which a combination of erosion and continuing geological changes likely caused it to drain. At its longest, Lake Hitchcock stretched from the moraine dam at present-day Rocky Hill, Connecticut, to St. Johnsbury, Vermont (about ). Although the rift valley through which the river flows above Rocky Hill actually continues south to New Haven, on Long Island Sound, the obstructing moraine at Rocky Hill diverted the river southeast to its present mouth at Old Saybrook. Lake Hitchcock is an important part of the geology of Connecticut. It experienced annual layering of sediments, or varves: silt and sand in the summertime (due to glacial meltwater) and clay in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Lakes Albany, Champlain, Hitchcock, Winsooski, & Merrimack
A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The Last Glacial Period ended about 15,000 years ago. The Holocene is the current interglacial. A time with no glaciers on Earth is considered a Greenhouse and icehouse Earth, greenhouse climate state. Quaternary Period Within the Quaternary, which started about 2.6 million years before present, there have been a number of glacials and interglacials. At least eight glacial cycles have occurred in the last 740,000 years alone. Penultimate Glacial Period The Penultimate Glacial Period (PGP) is the glacial period that occurred before the Last Glacial Period. It began about 194,000 years ago and ended 135,000 years ago, with the beginning of the Eemian interglacial. Last Glacial Period The last glacial period was the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentology
Sedimentology encompasses the study of modern sediments such as sand, silt, and clay, and the processes that result in their formation (erosion and weathering), transport, deposition and diagenesis. Sedimentologists apply their understanding of modern processes to interpret geologic history through observations of sedimentary rocks and sedimentary structures. Sedimentary rocks cover up to 75% of the Earth's surface, record much of the Earth's history, and harbor the fossil record. Sedimentology is closely linked to stratigraphy, the study of the physical and temporal relationships between rock layers or strata. The premise that the processes affecting the earth today are the same as in the past is the basis for determining how sedimentary features in the rock record were formed. By comparing similar features today to features in the rock record—for example, by comparing modern sand dunes to dunes preserved in ancient aeolian sandstones—geologists reconstruct past environmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Former Lakes Of The United States
A former is an object, such as a template, gauge or cutting die, which is used to form something such as a boat's hull. Typically, a former gives shape to a structure that may have complex curvature. A former may become an integral part of the finished structure, as in an aircraft fuselage, or it may be removable, being using in the construction process and then discarded or re-used. Aircraft formers Formers are used in the construction of aircraft fuselage, of which a typical fuselage has a series from the nose to the empennage, typically perpendicular to the longitudinal axis of the aircraft. The primary purpose of formers is to establish the shape of the fuselage and reduce the column length of stringers to prevent instability. Formers are typically attached to longerons, which support the skin of the aircraft. The "former-and-longeron" technique (also called stations and stringers) was adopted from boat construction, and was typical of light aircraft built until the ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Stowe
Lake Stowe was a glacial lake that formed in Central Vermont approximately 15,000 years ago in the late Pleistocene epoch. After the Laurentide Ice Sheet retreated, glacial ice melt accumulated at the terminal moraine. The lake existed until the glacier had completely melted. Then it flowed out through the Lamoille River valley. The lake was named after Stowe, near where evidence of the lake was discovered. See also *Champlain Sea *Lake Albany *Lake Hitchcock *Lake Merrimack Lake Merrimack was a glacial lake that formed during the late Pleistocene epoch. After the Laurentide Ice Sheet retreated, glacial ice melt accumulated at the terminal moraine and blocked up the Merrimack River, creating the narrow lake. The lake ex ... References Former lakes of the United States Stowe, Vermont Lakes of Vermont Proglacial lakes Bodies of water of Lamoille County, Vermont Glacial lakes of the United States {{Vermont-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Merrimack
Lake Merrimack was a glacial lake that formed during the late Pleistocene epoch. After the Laurentide Ice Sheet retreated, glacial ice melt accumulated at the terminal moraine and blocked up the Merrimack River, creating the narrow lake. The lake extended from Manchester to Plymouth, New Hampshire. It is unknown when the lake was drained. Lake Hitchcock is an important part of the geology of New Hampshire. It experienced annual layering of sediments, or varves: silt and sand in the summertime (due to glacial meltwater) and clay in the wintertime (as the lake froze). See also *Lake Winnipesaukee *Champlain Sea *Lake Albany *Lake Hitchcock Lake Hitchcock was a glacial lake that formed approximately 15,000 years ago in the late Pleistocene epoch. After the Laurentide Ice Sheet retreated, glacial ice melt accumulated at the terminal moraine and blocked up the Connecticut River, cre ... * Lake Stowe References External linksInformation on the Pemigewasset River {{DEFAULTSOR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Connecticut
Glacial Lake Connecticut formed over what is now Long Island Sound and coastal Connecticut at the fore edge of the ice sheet of the Wisconsin glaciation, as the lobe of the Laurentide Ice Sheet began to retreat, some 18 to 20,000 years before present. It was dammed by the terminal moraine that now forms the spine of Long Island and Fishers Island. About 15,000 BP, the moraine dam that impounded Lake Connecticut failed; the outlet, known as The Race for its tidal rip current A rip current, often simply called a rip (or misleadingly a ''rip tide''), is a specific kind of water current that can occur near beaches with breaking waves. A rip is a strong, localized, and narrow current of water which moves directly away ...s, lies between the North Fork, Suffolk County, New York, North Fork of Long Island and Fishers Island. For a time, much of the lake bed was exposed to wind-driven erosion: the cue is found in soundings that reveal regional Unconformity, unconformities in the sedi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Albany
Glacial Lake Albany was a prehistoric North American proglacial lake that formed during the end of the Wisconsinan glaciation. It existed between 15,000 and 12,600 years ago and was created when meltwater from a retreating glacier, along with water from rivers such as the Iromohawk, became ice dammed in the Hudson Valley. Organic materials in Lake Albany deposits have been carbon dated to approximately 11,700 years ago. The lake spanned approximately from present-day Poughkeepsie to Glens Falls. Lake Albany drained about 10,500 years ago through the Hudson River due to post-glacial rebound. When the lake drained it exposed the sandy and gravelly glaciolacustrine deposits left by the glacier, along a broad plain just west of Schenectady, where the Mohawk emptied into the lake. Dune and deltaic A river delta is a landform shaped like a triangle, created by deposition of sediment that is carried by a river and enters slower-moving or stagnant water. This occurs where a river ente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Champlain Sea
The Champlain Sea (french: Mer de Champlain) was a prehistoric inlet of the Atlantic Ocean into the North American continent, created by the retreating ice sheets during the closure of the last glacial period. The inlet once included lands in what are now the Canadian provinces of Quebec and Ontario, as well as parts of the American states of New York and Vermont. Origins The mass of ice from the continental ice sheets had depressed the rock beneath it over millennia. At the end of the last glacial period, while the rock was still depressed, the Saint Lawrence and Ottawa River valleys, as well as modern Lake Champlain, at that time the Lake Vermont, were below sea level and flooded with rising worldwide sea levels, once the ice no longer prevented the ocean from flowing into the region. As the land gradually rose again, in the process known as isostatic rebound, the sea coast gradually retreated to its current location. The sea lasted from about 13,000 years ago to about ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amherst College
Amherst College ( ) is a private liberal arts college in Amherst, Massachusetts. Founded in 1821 as an attempt to relocate Williams College by its then-president Zephaniah Swift Moore, Amherst is the third oldest institution of higher education in Massachusetts. The institution was named after the town, which in turn had been named after Jeffery, Lord Amherst, Commander-in-Chief of British forces of North America during the French and Indian War. Originally established as a men's college, Amherst became coeducational in 1975. Amherst is an exclusively undergraduate four-year institution; 1,971 students were enrolled in fall 2021. Admissions is highly selective, and it frequently ranks at or near the top in most rankings of liberal arts schools. Students choose courses from 41 major programs in an open curriculum and are not required to study a core curriculum or fulfill any distribution requirements; students may also design their own interdisciplinary major. Amherst competes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edward Hitchcock
Edward Hitchcock (May 24, 1793 – February 27, 1864) was an American geologist and the third President of Amherst College (1845–1854). Life Born to poor parents, he attended newly founded Deerfield Academy, where he was later principal, from 1815 to 1818. In 1821 he was ordained as a Congregationalist pastor and served as pastor of the Congregational Church in Conway, Massachusetts, 1821–1825. He left the ministry to become Professor of Chemistry and Natural History at Amherst College. He held that post from 1825 to 1845, serving as Professor of Natural Theology and Geology from 1845 until his death in 1864. In 1845, Hitchcock became President of the College, a post he held until 1854. As president, Hitchcock was responsible for Amherst's recovery from severe financial difficulties. He is also credited with developing the college's scientific resources and establishing its reputation for scientific teaching. In addition to his positions at Amherst, Hitchcock was a we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brickworks
A brickworks, also known as a brick factory, is a factory for the manufacturing of bricks, from clay or shale. Usually a brickworks is located on a clay bedrock (the most common material from which bricks are made), often with a quarry for clay on site. In earlier times bricks were made at brickfields, which would be returned to agricultural use after the clay layer was exhausted. Equipment Most brickworks have some or all of the following: *A kiln, for firing, or 'burning' the bricks. *Drying yard or shed, for drying bricks before firing. *A building or buildings for manufacturing the bricks. *A quarry for clay. *A pugmill or clay preparation plant (see below). Brick making Bricks were originally made by hand, and that practice continues in developing countries and with a few specialty suppliers. Large industrial brickworks supply clay from a quarry, moving it by conveyor belt or truck/lorry to the main factory, although it may be stockpiled outside before entering the mac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varve
A varve is an annual layer of sediment or sedimentary rock. The word 'varve' derives from the Swedish word ''varv'' whose meanings and connotations include 'revolution', 'in layers', and 'circle'. The term first appeared as ''Hvarfig lera'' (varved clay) on the first map produced by the Geological Survey of Sweden in 1862. Initially, "varve" referred to each of the separate components comprising a single annual layer in glacial lake sediments, but at the 1910 Geological Congress, the Swedish geologist Gerard De Geer (1858–1943) proposed a new formal definition, where varve means the whole of any annual sedimentary layer. More recently introduced terms such as 'annually laminated' are synonymous with varve. Of the many rhythmites in the geological record, varves are one of the most important and illuminating in studies of past climate change. Varves are amongst the smallest-scale events recognised in stratigraphy. An annual layer can be highly visible because the particles wash ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
