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Deformation (volcanology)
In volcanology, deformation is any change in the shape of a volcano or the land surrounding it. This can be in the form of inflation, which is a response to pressurization, or deflation, which is a response to depressurization. Inflation is represented by swelling of the ground surface, a volcanic edifice, or a subsurface magma body. It can be caused by magma accumulation, exsolution of volatiles, geothermal processes, heating, and tectonic compression. Deflation is represented by shrinking of the ground surface, a volcanic edifice, or a subsurface magma body. It can be caused by magma withdrawal (related to intrusion or eruption), volatile escape, thermal contraction, phase changes during crystallization, and tectonic extension. Deformation is a key indicator of pre-eruptive unrest at many active volcanoes. The term bradyseism is used in the volcanological literature to mean the vertical ground movements associated with the Phlegraean Fields volcanic area west of Naples, Ital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mauna Loa Summit Inflation
Mauna or Mouna may refer to: * Mauna (moth), ''Mauna'' (moth), genus of moths in the family Geometridae * Mauna (silence), silence in Hindu philosophy * Mauna, Käbschütztal, village in Käbschütztal, Germany * A Hawaiian word for mountain, used in the following Hawaiian volcano names: ** Mauna Loa, on Hawai'i ** Mauna Kea, on Hawai'i ** Mauna Ulu, cinder cone of Kīlauea, on Hawai'i ** Mauna Iki, cinder cone of Kīlauea, on Hawai'i ** Mauna Haleakalā, on Maui ** Mauna Hina, cinder cone of Haleakalā {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontiers In Earth Science
Frontiers Media SA is a publisher of peer-reviewed, open access, scientific journals currently active in science, technology, and medicine. It was founded in 2007 by Kamila and Henry Markram, and has since expanded to other academic fields. Frontiers is based in Lausanne, Switzerland, with other offices in London, Madrid, Seattle and Brussels. In 2022, Frontiers employed more than 1,400 people, across 14 countries. All Frontiers journals are published under a Creative Commons Attribution License. As of 2022, Frontiers publishes over 185 academic journals, including 48 journals indexed within the Science Citation Index Expanded, and 4 journals indexed within the Social Sciences Citation Index, with a total of 51 journals ranked with an impact factor. Frontiers journals are included in the Directory of Open Access Journals (DOAJ). Frontiers is also a member of the Open Access Scholarly Publishers Association (OASPA), a participating publisher and supporter of the Initiative for Op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subglacial Volcano
A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava. Today they are most common in Iceland and Antarctica; older formations of this type are found also in British Columbia and Yukon Territory, Canada. During the eruption, the heat of the lava from the subglacial volcano melts the overlying ice. The water quickly cools the lava, resulting in pillow lava shapes similar to those of underwater volcanoes. When the pillow lavas break off and roll down the volcano slopes, pillow breccia, tuff breccia, and hyaloclastite form. The meltwater may be released from below the ice as happened in Iceland in 1996 when the Grímsvötn caldera erupted, melting 3 km3 of ice and giving rise to a large glacial lake outburst flood. The shape of subglacial volcanoes tends to be quite characteristic and unusual, with a flatten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptodome
In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on Earth are lava dome forming. The geochemistry of lava domes can vary from basalt (e.g. Semeru, 1946) to rhyolite (e.g. Chaiten, 2010) although the majority are of intermediate composition (such as Santiaguito, dacite-andesite, present day) The characteristic dome shape is attributed to high viscosity that prevents the lava from flowing very far. This high viscosity can be obtained in two ways: by high levels of silica in the magma, or by degassing of fluid magma. Since viscous basaltic and andesitic domes weather fast and easily break apart by further input of fluid lava, most of the preserved domes have high silica content and consist of rhyolite or dacite. Existence of lava domes has been suggested for some domed structures on the Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicic
Silicic is an adjective to describe magma or igneous rock rich in silica. The amount of silica that constitutes a silicic rock is usually defined as at least 63 percent. Granite and rhyolite are the most common silicic rocks. Silicic is the group of silicate magmas which will eventually crystallise a relatively small proportion of ferromagnesian silicates, such as amphibole, pyroxene, and biotite. The main constituents of a silicic rock will be minerals rich in silica-minerals, like silicic Feldspar or even free silica as Quartz. Example The " Shammar group" is a silicic and volcaniclastic sequence in northwestern Saudi Arabia. See also *Felsic *Mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ... References Igneous rocks {{Petrology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magma Chamber
A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces buoyant forces on the magma that tend to drive it upwards. If the magma finds a path to the surface, then the result will be a volcanic eruption; consequently, many volcanoes are situated over magma chambers. These chambers are hard to detect deep within the Earth, and therefore most of those known are close to the surface, commonly between 1 km and 10 km down. Dynamics of magma chambers Magma rises through cracks from beneath and across the crust because it is less dense than the surrounding rock. When the magma cannot find a path upwards it pools into a magma chamber. These chambers are commonly built up over time, by successive horizontal or vertical magma injections. Influx of new magma causes reaction of pre-existing crystals and the pressure in the chamber to increase. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prediction Of Volcanic Activity
Prediction of volcanic activity, or volcanic eruption forecasting, is an interdisciplinary monitoring and research effort to predict the time and severity of a volcano's eruption. Of particular importance is the prediction of hazardous eruptions that could lead to catastrophic loss of life, property, and disruption of human activities. Seismic waves (seismicity) General principles of volcano seismology * Seismic activity (earthquakes and tremors) always occurs as volcanoes awaken and prepare to erupt and are a very important link to eruptions. Some volcanoes normally have continuing low-level seismic activity, but an increase may signal a greater likelihood of an eruption. The types of earthquakes that occur and where they start and end are also key signs. Volcanic seismicity has three major forms: short-period earthquake, long-period earthquake, and harmonic tremor. * Short-period earthquakes are like normal fault-generated earthquakes. They are caused by the fracturing of bri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deformation Monitoring
Deformation monitoring (also referred to as deformation survey) is the systematic measurement and tracking of the alteration in the shape or dimensions of an object as a result of stresses induced by applied loads. Deformation monitoring is a major component of logging measured values that may be used for further computation, deformation analysis, predictive maintenance and alarming. Deformation monitoring is primarily related to the field of applied surveying, but may also be related to civil engineering, mechanical engineering, construction, and geology. The measuring devices used for deformation monitoring depend on the application, the chosen method, and the preferred measurement interval. Measuring devices Measuring devices (or sensors) can be sorted in two main groups—geodetic and geotechnical sensors. Both measuring devices can be seamlessly combined in modern deformation monitoring. *Geodetic measuring devices measure georeferenced (relative to established locations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United Nations Educational, Scientific And Cultural Organization
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations (UN) aimed at promoting world peace and security through international cooperation in education, arts, sciences and culture. It has 193 member states and 12 associate members, as well as partners in the non-governmental, intergovernmental and private sector. Headquartered at the World Heritage Centre in Paris, France, UNESCO has 53 regional field offices and 199 national commissions that facilitate its global mandate. UNESCO was founded in 1945 as the successor to the League of Nations's International Committee on Intellectual Cooperation.English summary). Its constitution establishes the agency's goals, governing structure, and operating framework. UNESCO's founding mission, which was shaped by the Second World War, is to advance peace, sustainable development and human rights by facilitating collaboration and dialogue among nations. It pursues this objective th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical region. Italy is also considered part of Western Europe, and shares land borders with France, Switzerland, Austria, Slovenia and the enclaved microstates of Vatican City and San Marino. It has a territorial exclave in Switzerland, Campione. Italy covers an area of , with a population of over 60 million. It is the third-most populous member state of the European Union, the sixth-most populous country in Europe, and the tenth-largest country in the continent by land area. Italy's capital and largest city is Rome. Italy was the native place of many civilizations such as the Italic peoples and the Etruscans, while due to its central geographic location in Southern Europe and the Mediterranean, the country has also historically been home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naples
Naples (; it, Napoli ; nap, Napule ), from grc, Νεάπολις, Neápolis, lit=new city. is the regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 909,048 within the city's administrative limits as of 2022. Its province-level municipality is the third-most populous metropolitan city in Italy with a population of 3,115,320 residents, and its metropolitan area stretches beyond the boundaries of the city wall for approximately 20 miles. Founded by Greeks in the first millennium BC, Naples is one of the oldest continuously inhabited urban areas in the world. In the eighth century BC, a colony known as Parthenope ( grc, Παρθενόπη) was established on the Pizzofalcone hill. In the sixth century BC, it was refounded as Neápolis. The city was an important part of Magna Graecia, played a major role in the merging of Greek and Roman society, and was a significant cultural centre under the Romans. Naples served a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
