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Caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the structural integrity of such a chamber, greatly diminishing its capacity to support its own roof and any substrate or rock resting above. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface (from one to dozens of kilometers in diameter). Although sometimes described as a Volcanic crater, crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur over the course of a century, the formation of a caldera is a rare event, occurring only a few times within a given window of 100 years. Only eight caldera-forming collapses are known to have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caldera De Taburiente
Caldera de Taburiente National Park () is a national park on the island of La Palma, Canary Islands, Spain. It contains the Caldera de Taburiente, which dominates the northern part of the island, and was designated as a national park in 1954. The telescopes of the Roque de los Muchachos Observatory are situated very close to the summit. Toponym The word ''caldera'' means cauldron in Spanish. ''Taburiente'' is not a Spanish word but derives from the Guanche language and means "plain, level". Geography The Caldera de Taburiente is a topographic depression about 10 km across, and in places the walls tower 2000 m over the caldera floor. The highest point is the Roque de los Muchachos on the northern wall, at 2426 m altitude, which can be reached by road. The ''Cumbrecita'' is at a lower point in the south-eastern part of the caldera's rim. In the south-west, the caldera opens to the sea, through a river-floored valley called the Barranco de las Angustias. (The river is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Palma
La Palma (, ), also known as ''La isla bonita'' () and historically San Miguel de La Palma, is the most northwesterly island of the Canary Islands, a Spanish autonomous community and archipelago in Macaronesia in the North Atlantic Ocean. La Palma has an area of making it the fifth largest of the eight main Canary Islands. The total population at the start of 2023 was 84,338, of whom 15,522 lived in the capital, Santa Cruz de La Palma and 20,375 in Los Llanos de Aridane. Its highest mountain is the Roque de los Muchachos, at , being second among the peaks of the Canaries after the Teide massif on Tenerife. In 1815, the German geologist Leopold von Buch visited the Canary Islands. It was as a result of his visit to Tenerife, where he visited the Las Cañadas caldera, and then later to La Palma, where he visited the Taburiente caldera, that the Spanish word for cauldron or large cooking pot – "caldera" – was introduced into the geological vocabulary. In the center of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and because most of Earth's plate boundaries are underwater, most volcanoes are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes resulting from divergent tectonic activity are usually non-explosive whereas those resulting from convergent tectonic activity cause violent eruptions."Mid-ocean ridge tectonics, volcanism and geomorphology." Geology 26, no. 455 (2001): 458. https://macdonald.faculty.geol.ucsb.edu/papers/Macdonald%20Mid-Ocean%20Ridge%20Tectonics.pdf Volcanoes can also form where there is str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring Dike
A ring dike or ring dyke is an Intrusive rock, intrusive igneous body that is circular, oval or arcuate in plan and has steep contacts. While the widths of ring dikes differ, they can be up to several thousand meters. The most commonly accepted method of ring dike formation is directly related to collapse calderas.Gudmundsson, Agust. "Formation of collapse calderas." ''Geology'' 16.9 (1988): 808–10. Caldera collapse and ring dike formation Collapse calderas form due to the emptying of a magma chamber. Effusive eruptions that take place on the flanks of the associated volcano and a Fissure vent, fissure system that direct magma away from the chamber are both mechanisms that can empty a magma chamber. As pressure in the magma chamber changes, an increase in tensile stresses create tension fractures at the surface of the volcano. The geometry of the top of the magma chamber dictates the location and magnitude of the tension fractures. In addition, it was found that the higher th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canary Islands
The Canary Islands (; ) or Canaries are an archipelago in the Atlantic Ocean and the southernmost Autonomous communities of Spain, Autonomous Community of Spain. They are located in the northwest of Africa, with the closest point to the continent being 100 kilometres (62 miles) away. The islands have a population of 2.25 million people and are the most populous overseas Special member state territories and the European Union, special territory of the European Union. The seven main islands are from largest to smallest in area, Tenerife, Fuerteventura, Gran Canaria, Lanzarote, La Palma, La Gomera, and El Hierro. The only other populated island is Graciosa, Canary Islands, La Graciosa, which administratively is dependent on Lanzarote. The archipelago includes many smaller islands and islets, including Alegranza, Islote de Lobos, Isla de Lobos, Montaña Clara, Roque del Oeste, and Roque del Este. It includes a number of rocks, including Roque de Garachico, Garachico and Roques de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Eruption
A volcanic eruption occurs when material is expelled from a volcanic vent or fissure. Several types of volcanic eruptions have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series. There are three main types of volcanic eruptions. Magmatic eruptions involve the decompression of gas within magma that propels it forward. Phreatic eruptions are driven by the superheating of steam due to the close proximity of magma. This type exhibits no magmatic release, instead causing the granulation of existing rock. Phreatomagmatic eruptions are driven by the direct interaction of magma and water, as opposed to phreatic eruptions, where no fresh magma reaches the surface. Within these broad eruptive types are several subtypes. The we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kīlauea
Kīlauea ( , ) is an active shield volcano in the Hawaiian Islands. It is located along the southeastern shore of Hawaii (island), Hawaii Island. The volcano is between 210,000 and 280,000 years old and grew above sea level about 100,000 years ago. Since the islands were settled, it has been the most volcano#Active, active of the Hawaii (island)#Volcanism, five volcanoes that together form the island and among the most active volcanoes on Earth. The most recent eruption began in December 2024, with episodic lava fountains and flows continuing into 2025. Kīlauea is the second-youngest product of the Hawaiian hotspot and the current eruptive center of the Hawaiian–Emperor seamount chain. Because it lacks topographic prominence and its activities historically coincided with those of Mauna Loa, Kīlauea was once thought to be a satellite of its much larger neighbor. Kīlauea has a large, fairly recently formed caldera at its summit and two active rift zones, one extending east ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leopold Von Buch
Christian Leopold von Buch (26 April 1774 – 4 March 1853), usually cited as Leopold von Buch, was a German geologist and paleontologist born in Stolpe an der Oder (now a part of Angermünde, Brandenburg) and is remembered as one of the most important contributors to geology in the first half of the nineteenth century. His scientific interest was devoted to a broad spectrum of geological topics: volcanism, petrology, fossils, stratigraphy and mountain formation. His most remembered accomplishment is the scientific definition of the Jurassic, Jurassic system. Biography Buch studied with Alexander von Humboldt under Abraham Gottlob Werner at the Technical University of Bergakademie Freiberg, mining school in Freiberg, Saxony. He afterwards completed his education at the universities of University of Halle, Halle and University of Göttingen, Göttingen. German and Italian explorations He began writing on geological topics early in life. His ''Versuch einer mineralogischen Besch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenerife
Tenerife ( ; ; formerly spelled ''Teneriffe'') is the largest and most populous island of the Canary Islands, an Autonomous communities of Spain, autonomous community of Spain. With a land area of and a population of 965,575 inhabitants as of April 2025, it is the most populous island in Spain and the entire Macaronesia region. Tenerife is also home to 42.7% of the total population of the archipelago. More than seven million tourists (7,384,707 in 2024) visit Tenerife each year, making it by far the most visited island in the archipelago. It is one of the most important tourist destinations in Spain and the world, hosting one of the world's largest carnivals, the Carnival of Santa Cruz de Tenerife. The capital of the island, , is also the seat of the island council (). That city and are the co-capitals of the Autonomous communities of Spain, autonomous community of the Canary Islands. The two cities are both home to governmental institutions, such as the offices of the preside ... [...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. The influx of new magma causes reaction of pre-existing crystals and the pressure in the chamber to increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Crater
A volcanic crater is an approximately circular depression in the ground caused by volcanic activity. It is typically a bowl-shaped feature containing one or more vents. During volcanic eruptions, molten magma and volcanic gases rise from an underground magma chamber, through a conduit, until they reach the crater's vent, from where the gases escape into the atmosphere and the magma is erupted as lava. A volcanic crater can be of large dimensions, and sometimes of great depth. During certain types of explosive eruptions, a volcano's magma chamber may empty enough for an area above it to subside, forming a type of larger depression known as a caldera. Geomorphology In most volcanoes, the crater is situated at the top of a mountain formed from the erupted volcanic deposits such as lava flows and tephra. Volcanoes that terminate in such a summit crater are usually of a conical form. Other volcanic craters may be found on the flanks of volcanoes, and these are commonly refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinkhole
A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water enters into underground passages known as ''ponor'', swallow hole or swallet. A ''cenote'' is a type of sinkhole that exposes groundwater underneath. ''Sink'', and ''stream sink'' are more general terms for sites that drain surface water, possibly by infiltration into sediment or crumbled rock. Most sinkholes are caused by Karst topography, karst processes – the chemical dissolution of carbonate rocks, collapse or suffosion processes. Sinkholes are usually circular and vary in size from tens to hundreds of Metre, meters both in diameter and depth, and vary in form from soil-lined bowls to bedrock-edged chasms. Sinkholes may form gradually or suddenly, and are found worldwide. Formation Natural processes Sinkholes may capture surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
