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Palaeomagnetism
Paleomagnetism (occasionally palaeomagnetism) is the study of prehistoric Earth's magnetic fields recorded in rocks, sediment, or archeological materials. Geophysicists who specialize in paleomagnetism are called ''paleomagnetists.'' Certain magnetic minerals in rocks can record the direction and intensity of Earth's magnetic field at the time they formed. This record provides information on the past behavior of the geomagnetic field and the past location of tectonic plates. The record of geomagnetic reversals preserved in volcanic and sedimentary rock sequences ( magnetostratigraphy) provides a time-scale that is used as a geochronologic tool. Evidence from paleomagnetism led to the revival of the continental drift hypothesis and its transformation into the modern theory of plate tectonics. Apparent polar wander paths provided the first clear geophysical evidence for continental drift, while marine magnetic anomalies did the same for seafloor spreading. Paleomagnetic dat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terranes
In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its distinctive geologic history, which is different from the surrounding areas—hence the term "exotic" terrane. The suture zone between a terrane and the crust it attaches to is usually identifiable as a fault. A sedimentary deposit that buries the contact of the terrane with adjacent rock is called an overlap formation. An igneous intrusion that has intruded and obscured the contact of a terrane with adjacent rock is called a stitching pluton. There is also an older usage of the term ''terrane'', which described a series of related rock formations or an area with a preponderance of a particular rock or rock group. Overview A tectonostratigraphic terrane did not necessarily originate as an independent microplate, since it may not contai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic
Oceanic may refer to: *Of or relating to the ocean *Of or relating to Oceania **Oceanic climate **Oceanic languages **Oceanic person or people, also called "Pacific Islander(s)" Places * Oceanic, British Columbia, a settlement on Smith Island, British Columbia, Canada *Oceanic, New Jersey, an unincorporated community within Rumson Borough, Monmouth County, New Jersey, United States Ships named Oceanic * , the White Star Line's first ocean liner ** Oceanic-class ocean liner, class of liners based on SS ''Oceanic'' (1870) * , a transatlantic ocean liner built for the White Star Line * , a project of the 1930s * , built as SS ''Independence'' in 1950 * , also named ''Big Red Boat I'' by Premier Cruises Art, entertainment, and media Fictional entities * Oceanic Airlines or Oceanic Airways, often used in disaster movies * Oceanic Flight 815, a flight in the television series ''Lost'' Literature * "Oceanic" (novella), a 1998 sci-fi novella by Greg Egan Music ;Artists * Oceanic ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite
A meteorite is a rock (geology), rock that originated in outer space and has fallen to the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a Meteoroid#Fireball, fireball, also known as a shooting star; astronomers call the brightest examples "Bolide#Astronomy, bolides". Once it settles on the larger body's surface, the meteor becomes a meteorite. Meteorites vary greatly in size. For geologists, a bolide is a meteorite large enough to create an impact crater. Meteorites that are recovered after being observed as they transit the atmosphere and impact event, impact Earth are called meteorite falls. All others are known as meteorite finds. Meteorites have traditionally been divided into three broad categories: stony meteorites that are rocks, mainly composed of sil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brunhes–Matuyama Reversal
The Brunhes–Matuyama reversal, named after Bernard Brunhes and Motonori Matuyama, was a geologic event, approximately 781,000 years ago, when the Earth's magnetic field last underwent reversal. Estimations vary as to the abruptness of the reversal. A 2004 paper estimated that it took over several thousand years; a 2010 paper estimated that it occurred more quickly, perhaps within a human lifetime; a 2019 paper estimated that the reversal lasted 22,000 years. The apparent duration at any particular location can vary by an order of magnitude, depending on geomagnetic latitude and local effects of non-dipole components of the Earth's field during the transition. The Brunhes–Matuyama reversal is a marker for the Global Boundary Stratotype Section and Point (GSSP) defining the base of the Chibanian Stage and Middle Pleistocene Subseries at the Chiba section, Japan, which was officially ratified in 2020 by the International Union of Geological Sciences. It is useful in dating oce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the Phanerozoic eon. It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today); a proposed third epoch, the Anthropocene, was rejected in 2024 by IUGS, the governing body of the ICS. The Quaternary is typically defined by the Quaternary glaciation, the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. Research history In 1759 Giovanni Arduino proposed that the geological strata of northern Italy could be divided into four succ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motonori Matuyama
was a Japanese geophysicist who was (in the late 1920s) the first to provide systematic evidence that the Earth's magnetic field had been reversed in the early Pleistocene and to suggest that long periods existed in the past in which the polarity was reversed. He remarked that the Earth's field had later changed to the present polarity. The era of reversed polarity preceding the current ''Brunhes Chron'' of normal polarity is now called the ''Matuyama Reversed Chron''; and the transition between them is called the ''Brunhes–Matuyama'' or ''Matuyama-Brunhes'' reversal. Life Matuyama Motonori was born at Uyeda (now Usa) in Oita prefecture Japan on October 25, 1884, a son of a Zen abbot, Sumie (Sumiye) Tengai. His name was at first registered as Suehara Motonori after his mother’s family name, Suehara Kou, and was later changed to Sumie Motonori when his father became the chief priest at an eminent Zen Buddhist temple in Yamaguchi. In 1910 he was adopted by the Matsuyama (松 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Louis Mercanton
__NOTOC__ Paul-Louis Mercanton (11 May 1876 – 25 February 1963) was a Swiss glaciologist, meteorologist and Arctic explorer. Biography Mercanton was born in Lausanne on 11 May 1876, the son of Eugène Mercanton, a lawyer, and Félicie Marie Lavanchy. He graduated in electrical engineering from the University of Lausanne in 1899, and obtained a doctorate in physics from the same university in 1901. Mercanton was a professor of physics and electricity, then of meteorology and geophysics, at Lausanne from 1904 to 1938. He married Alice Marguerite Colomb in 1907. Mercanton directed Vaud's meteorological service from 1911 to 1941 and the Swiss Central Meteorological Station in Zurich from 1934 to 1941, and was editor and co-author of ''Variations périodiques des glaciers des Alpes suisses'' ("Periodic Variations of the Glaciers of the Swiss Alps") between 1907 and 1954. He also regularly wrote reports on other glaciers of Europe. Mercanton was a pioneer by publishing in 191 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bernard Brunhes
Antoine Joseph Bernard Brunhes (3 July 1867 – 10 May 1910) was a French geophysicist known for his pioneering work in paleomagnetism, in particular, his 1906 discovery of geomagnetic reversal. The current period of normal polarity, ''Brunhes Chron'', and the Brunhes–Matuyama reversal are named for him. Brunhes was educated at the École Normale Supérieure in Paris, from which he graduated as an '' agrégé'' qualified in physics. Appointed at Université Lille Nord de France, he taught physics and electrical engineering at École centrale de Lille from 1893 to 1895. In November 1900, he was appointed as head of the Puy-de-Dôme Observatory, built on an extinct volcano in the Auvergne region of France, where he worked until his death in 1910. It was during his time at the observatory that he made the crucial observation that led to his discovery of geomagnetic reversal. In 1905, he found that rocks in an ancient lava flow at Pontfarin in the commune of Cézens (part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightning Strike
A lightning strike or lightning bolt is a lightning event in which an electric discharge takes place between the atmosphere and the ground. Most originate in a cumulonimbus cloud and terminate on the ground, called cloud-to-ground (CG) lightning. A less common type of strike, ground-to-cloud (GC) lightning, is upward-propagating lightning initiated from a tall grounded object and reaching into the clouds. About 25% of all lightning events worldwide are strikes between the atmosphere and earth-bound objects. Most are intracloud (IC) lightning and cloud-to-cloud (CC), where discharges only occur high in the atmosphere.Cooray, Vernon. (2014). Lightning Flash (2nd Edition) - 1. Charge Structure and Geographical Variation of Thunderclouds. Page 4. Institution of Engineering and Technology. Lightning strikes the average commercial aircraft at least once a year, but modern engineering and design means this is rarely a problem. The movement of aircraft through clouds can even cause lightn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetization
In classical electromagnetism, magnetization is the vector field that expresses the density of permanent or induced magnetic dipole moments in a magnetic material. Accordingly, physicists and engineers usually define magnetization as the quantity of magnetic moment per unit volume. It is represented by a pseudovector M. Magnetization can be compared to Polarization density, electric polarization, which is the measure of the corresponding response of a material to an electric field in electrostatics. Magnetization also describes how a material responds to an applied magnetic field as well as the way the material changes the magnetic field, and can be used to calculate the forces that result from those interactions. The origin of the magnetic moments responsible for magnetization can be either microscopic electric currents resulting from the motion of electrons in atoms, or the Spin (physics), spin of the electrons or the nuclei. Net magnetization results from the response of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Von Humboldt
Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 1769 – 6 May 1859) was a German polymath, geographer, natural history, naturalist, List of explorers, explorer, and proponent of Romanticism, Romantic philosophy and Romanticism in science, science. He was the younger brother of the Prussian minister, philosopher, and linguistics, linguist Wilhelm von Humboldt (1767–1835). Humboldt's quantitative work on botany, botanical geography laid the foundation for the field of biogeography, while his advocacy of long-term systematic geophysical measurement pioneered modern Earth's magnetic field, geomagnetic and meteorology, meteorological monitoring. Humboldt and Carl Ritter are both regarded as the founders of modern geography as they established it as an independent scientific discipline. Between 1799 and 1804, Humboldt travelled extensively in the Americas, exploring and describing them for the first time from a non-Spanish European scientific point of view. His des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outcrop
An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth and other terrestrial planets. Features Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by soil and vegetation and cannot be seen or examined closely. However, in places where the overlying cover is removed through erosion or tectonic uplift, the rock may be exposed, or ''crop out''. Such exposure will happen most frequently in areas where erosion is rapid and exceeds the weathering rate such as on steep hillsides, mountain ridges and tops, river banks, and tectonically active areas. In Finland, glacial erosion during the last glacial maximum (ca. 11000 BC), followed by scouring by sea waves, followed by isostatic uplift has produced many smooth coastal and littoral outcrops. Bedrock and superficial deposits may also be exposed at the Earth's surface due to human exca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
