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Tanganasoga
Tanganasoga is the main volcano of El Hierro's El Golfo area in the Canary Islands, consisting of a cinder cone. The volcano is part of a much larger shield volcano system. The volcano El Hierro is a 278.5 km2 island, formed approx 1.2 million year agoJuan Carlos Carracedo, Simon Day: ''Canary Islands. Classic Geology in Europe 4.'' Harpenden, Terra, 2002, Page 2 after three successive eruptions, the island emerged from the ocean as a triangle of basaltic dykes topped with a volcanic cone more than 2,000 metres high. With continued activity resulting in the island expanding to have the largest number of volcanoes in the Canaries (over 500 cones, another 300 covered by more recent deposits), together with approximately 70 caves and volcanic galleries, including the Cueva de Don Justo whose collection of channels is over 6 km in length. Landslides have reduced the size and height of the island. Tanganasoga is now the main volcano on the island. Landslides There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanganasoga
Tanganasoga is the main volcano of El Hierro's El Golfo area in the Canary Islands, consisting of a cinder cone. The volcano is part of a much larger shield volcano system. The volcano El Hierro is a 278.5 km2 island, formed approx 1.2 million year agoJuan Carlos Carracedo, Simon Day: ''Canary Islands. Classic Geology in Europe 4.'' Harpenden, Terra, 2002, Page 2 after three successive eruptions, the island emerged from the ocean as a triangle of basaltic dykes topped with a volcanic cone more than 2,000 metres high. With continued activity resulting in the island expanding to have the largest number of volcanoes in the Canaries (over 500 cones, another 300 covered by more recent deposits), together with approximately 70 caves and volcanic galleries, including the Cueva de Don Justo whose collection of channels is over 6 km in length. Landslides have reduced the size and height of the island. Tanganasoga is now the main volcano on the island. Landslides There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanganasoga Panorama
Tanganasoga is the main volcano of El Hierro's El Golfo area in the Canary Islands, consisting of a cinder cone. The volcano is part of a much larger shield volcano system. The volcano El Hierro is a 278.5 km2 island, formed approx 1.2 million year agoJuan Carlos Carracedo, Simon Day: ''Canary Islands. Classic Geology in Europe 4.'' Harpenden, Terra, 2002, Page 2 after three successive eruptions, the island emerged from the ocean as a triangle of basaltic dykes topped with a volcanic cone more than 2,000 metres high. With continued activity resulting in the island expanding to have the largest number of volcanoes in the Canaries (over 500 cones, another 300 covered by more recent deposits), together with approximately 70 caves and volcanic galleries, including the Cueva de Don Justo whose collection of channels is over 6 km in length. Landslides have reduced the size and height of the island. Tanganasoga is now the main volcano on the island. Landslides There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
El Hierro
El Hierro, nicknamed ''Isla del Meridiano'' (the "Meridian Island"), is the second-smallest and farthest-south and -west of the Canary Islands (an autonomous community of Spain), in the Atlantic Ocean off the coast of Africa, with a population of 10,968 (2019). Its capital is Valverde. At , it is the second-smallest of the eight main islands of the Canaries. Name The name ''El Hierro'', although spelled like the Spanish word for 'iron', is not related to that word. The ''H'' in the name of the metal is derived from the ''F'' of Latin ''ferrum'' (compare ''higo'' for 'fig'), a phonetic mutation that was complete by the end of the Middle Ages. The confusion with the name of the metal had effects on the international naming of the island. As early as the 16th century, maps and texts called the island after the word for 'iron' in other languages: Portuguese ''Ferro'', French ''l'île de Fer'', and Latin '' Insula Ferri''. Nevertheless, the origin of the name ''ero'' or ''er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic
A volcano is a rupture 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 most 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 can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbidite
A turbidite is the geologic deposit of a turbidity current, which is a type of amalgamation of fluidal and sediment gravity flow responsible for distributing vast amounts of clastic sediment into the deep ocean. Sequencing Turbidites were first properly described by Arnold H. Bouma (1962), who studied deepwater sediments and recognized particular "fining-up intervals" within deep water, fine-grained shales, which were anomalous because they started at pebble conglomerates and terminated in shales. This was anomalous because within the deep ocean it had historically been assumed that there was no mechanism by which tractional flow could carry and deposit coarse-grained sediments into the abyssal depths. Bouma cycles begin with an erosional contact of a coarse lower bed of pebble to granule conglomerate in a sandy matrix, and grade up through coarse then medium plane parallel sandstone; through cross-bedded sandstone; rippled cross-bedded sand/silty sand, and finally lami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Landslide
A volcanic landslide or volcanogenic landslide is a type of mass wasting that takes place at volcanoes. Occurrences All volcanic edifices are susceptible to landslides, particularly stratovolcanoes and shield volcanoes where landslides are important processes. Volcanic landslides range in size from less than to more than . The largest volcanic landslides on Earth occur from submarine volcanoes and are several times larger than those that occur on land. Submarine landslides with volumes of have occurred in the Canary Islands within the last 43 million years, but the largest submarine landslides could have been up to in volume. Massive submarine landslides have also taken place in the Hawaiian Islands over the last several million years, the largest of which constitute significant portions of the islands from which they originated. Smaller landslides have also been identified at volcanoes on Mars and Venus. Martian landslides reach lengths of and more while the largest Ven ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cueva De Don Justo
The Cueva de Don Justo (or Cave of Don Justo) is one of approximately 70 caves and volcanic galleries on the island of El Hierro in the Canaries. The Cueva de Don Justo is over in length, the cave is located in the El Lajial pahoehoe lava field near the Orchilla lighthouse in the south of El Hierro, it is a wild cave that extends around the Irama mountain (also called Prim mountain) for a total distance of (with the parallel passages making up the extra distance). It was first explored and mapped by a speleological expedition in 1961, with further expeditions in 1974, 1976, and 1978, before the 1979 expedition completed the mapping of the of cave system. It is the longest of 28 known lava tubes on El Hierro, and the 3rd longest lava tube in the Canary Islands, and the 13th longest in the world. The cave has a maximum depth of 135 to and at some points has up to 8 passages running in parallel. The cave contains well developed troglobitic fauna including seven species of tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyke (geology)
A dike or dyke, in geological usage, is a sheet of rock that is formed in a fracture of a pre-existing rock body. Dikes can be either magmatic or sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reaches the surface. They are studied by geologists for the clue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canary Islands
The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocco. They are the southernmost of the autonomous communities of Spain. The islands have a population of 2.2 million people and they are the most populous 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 archipelago includes many smaller islands and islets, including La Graciosa, Alegranza, Isla de Lobos, Montaña Clara, Roque del Oeste, and Roque del Este. It also includes a number of rocks, including those of Salmor, Fasnia, Bonanza, Garachico, and Anaga. In ancient times, the island chain was often referred to as "the Fortunate Isles". The Canary Islands are the southernmost region of Spain, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
