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Lava Balloons
A lava balloon is a gas-filled bubble of lava that floats on the sea surface. It can be up to several metres in size. When it emerges from the sea, it is usually hot and often steaming. After floating for some time it fills with water and sinks again. Lava balloons can form in lava flows entering the sea and at volcanic vents, but they are not common. They have been observed in the Azores, Canary Islands, Hawaii, Japan, Mariana Islands and Mexico. Apparently, they are generated when gases trapped within magma form large bubbles that eventually rise to the sea surface. In the Canary Islands, balloons containing sediments were used to infer the age of the basement on which the volcano is constructed; these sediments were also at first misinterpreted as evidence of an impending large explosive eruption. Appearance Lava balloons are gas-filled bubbles surrounded by a crust formed by lava; their gas content allows them to float on the sea surface. Observed sizes range from at El H ...
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Lava Balloons Floating On Water, El Hierro 2011
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes'' ...
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Pantelleria
Pantelleria (; Sicilian: ''Pantiddirìa'', Maltese: ''Pantellerija'' or ''Qawsra''), the ancient Cossyra or Cossura, is an Italian island and comune in the Strait of Sicily in the Mediterranean Sea, southwest of Sicily and east of the Tunisian coast. On clear days Tunisia is visible from the island. Administratively Pantelleria's comune belongs to the Sicilian province of Trapani. The population of Pantelleria 2022 was 7,335 in 2022, according to istat.it. Description With an area of , Pantelleria is the largest volcanic satellite island of Sicily. The last eruption occurred below sea level in 1891, and today phenomena related to volcanic activity are present, such as hot springs and fumaroles. The highest peak, the ''Montagna Grande'', reaches above sea level. The islanders speak Pantesco, a dialect of Sicilian influenced by Arabic. Names The Carthaginians knew the island as ( xpu, 𐤉𐤓𐤍𐤌) or (). The Greek geographers recorded it as ''Kossyra'' ( grc, ...
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Volcanic Vent
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 plates slide pa ...
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Fishing Tackle
Fishing tackle is the equipment used by anglers when fishing. Almost any equipment or gear used in fishing can be called fishing tackle, examples being hooks, lines, baits/ lures, rods, reels, floats, sinkers/ feeders, nets, stringers/ keepnets/ livewells, spears, gaffs, traps, waders and tackle boxes, as well as any wire, snaps, beads, spoons, blades, spinners, clevises and tools that make it easy to tie knots. Gear that is attached to the end of a fishing line (and thus get cast out along with the bait) is collectively called terminal tackles, which include hooks, leaders, floats, sinkers/feeders, swivels and any attached snaps and/or split rings. Sometimes the term " rig" is used for a routine assembly of terminal tackle combination. Fishing tackle can be contrasted with fishing techniques. Fishing tackle refers to the physical equipment that is used when fishing, whereas fishing techniques refers to the manner in which the tackle is used (or "presented") when ...
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Kermadec Islands
The Kermadec Islands ( mi, Rangitāhua) are a subtropical island arc in the South Pacific Ocean northeast of New Zealand's North Island, and a similar distance southwest of Tonga. The islands are part of New Zealand. They are in total area and uninhabited, except for the permanently manned Raoul Island Station, the northernmost outpost of New Zealand. The islands are listed with the New Zealand outlying islands. The islands are an immediate part of New Zealand, but not part of any region or district, but instead an ''Area Outside Territorial Authority''. Toponymy The islands were named after the Breton captain Jean-Michel Huon de Kermadec, who visited the islands as part of the d'Entrecasteaux expedition in the 1790s. The topographic particle "Kermadec" is of Breton origin and is a lieu-dit in Pencran in Finistère where '' ker'' means village, residence and madec a proper name derived from '' mad'' (which means 'good') with the suffix '' -ec'', used to form adjectives in ...
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Macauley Island
Macauley Island is a volcanic island in New Zealand's Kermadec Islands, approximately halfway between New Zealand's North Island and Tonga in the southwest Pacific Ocean. It is part of a larger submarine volcano that features a wide underwater caldera northwest of Macauley Island. Two islets, Haszard Island and Newcome Rock, lie east offshore of Macauley Island. The island is mostly surrounded by high cliffs that make accessing it difficult; the inland parts are mostly gently sloping terrain covered with ferns and grasses. The island was formed during several volcanic episodes that produced mainly basaltic rocks as lava flows. During the Holocene, a large explosive eruption produced the Sandy Bay Tephra; this eruption may have had a volume of more than and the Macauley caldera might have formed during that occasion. Later, the Haszard Formation built most of the current surface of Macauley Island. Two uncertain eruptions took place during the 19th century offshore Macaule ...
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Tangaroa
Tangaroa (Takaroa in the South Island) is the great of the sea, lakes, rivers, and creatures that live within them, especially fish, in Māori mythology. As Tangaroa-whakamau-tai he exercises control over the tides. He is sometimes depicted as a whale. In some of the Cook Islands he has similar roles, though in Manihiki he is the fire deity that Māui steals from, which in Māori mythology is instead Mahuika, a goddess of fire. Māori traditions Tangaroa is a son of Ranginui and Papatūānuku, Sky and Earth. After he joins his brothers Rongo, Tū, Haumia, and Tāne in the forcible separation of their parents, he is attacked by his brother Tāwhirimātea, the of storms, and forced to hide in the sea. Tangaroa is the father of many sea creatures. Tangaroa's son, Punga, has two children, Ikatere, the ancestor of fish, and Tū-te-wehiwehi (or Tū-te-wanawana), the ancestor of reptiles. Terrified by Tāwhirimātea's onslaught, the fish seek shelter in the sea, and the reptil ...
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Sea God
A water deity is a deity in mythology associated with water or various bodies of water. Water deities are common in mythology and were usually more important among civilizations in which the sea or ocean, or a great river was more important. Another important focus of worship of water deities has been springs or holy wells. As a form of animal worship, whales and snakes (hence dragons) have been regarded as godly deities throughout the world (as are other animals such as turtles, fish, crabs, and sharks). In Asian lore, whales and dragons sometimes have connections. Serpents are also common as a symbol or as serpentine deities, sharing many similarities with dragons. Africa and the Mediterranean Sub-Sahara Africa Western Niger-Congo Benin * Ezili, goddess of sweet water, beauty, and love. Dogon *Nommos, amphibious spirits that are worshiped as ancestors. Serer * Mindiss (or Mindis) is not a deity in Serer religion, but a pangool with goddess–like attributes. She is ...
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Māori People
The Māori (, ) are the indigenous Polynesian people of mainland New Zealand (). Māori originated with settlers from East Polynesia, who arrived in New Zealand in several waves of canoe voyages between roughly 1320 and 1350. Over several centuries in isolation, these settlers developed their own distinctive culture, whose language, mythology, crafts, and performing arts evolved independently from those of other eastern Polynesian cultures. Some early Māori moved to the Chatham Islands, where their descendants became New Zealand's other indigenous Polynesian ethnic group, the Moriori. Initial contact between Māori and Europeans, starting in the 18th century, ranged from beneficial trade to lethal violence; Māori actively adopted many technologies from the newcomers. With the signing of the Treaty of Waitangi in 1840, the two cultures coexisted for a generation. Rising tensions over disputed land sales led to conflict in the 1860s, and massive land confiscations, to which ...
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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 ...
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Socorro Island
Socorro Island ( es, Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying off the country's western coast. The size is 16.5 by 11.5 km (10.25 by 7.15 miles), with an area of . It is the largest of the four islands of the Revillagigedo Archipelago. The last eruption was in 1993. Geology The island rises abruptly from the sea to in elevation at its summit. Socorro Island is the emerged summit of a massive, predominately submarine shield volcano. The island is part of the northern Mathematicians Ridge, a mid-ocean ridge that became largely inactive 3.5 million years ago when activity moved to the East Pacific Rise. All four islands along with the many seamounts on the ridge are post-abandonment alkaline volcanoes. Socorro Island is unusual in that it is the only dominantly silicic peralkaline volcanic island in the Pacific Ocean. It most recently erupted in late Januaryearly February, 1993, which was a submarine flank eruption ...
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Scoria
Scoria is a pyroclastic, highly vesicular, dark-colored volcanic rock that was ejected from a volcano as a molten blob and cooled in the air to form discrete grains or clasts.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. It is typically dark in color (generally dark brown, black or purplish-red), and basaltic or andesitic in composition. Scoria is relatively low in density as a result of its numerous macroscopic ellipsoidal vesicles, but in contrast to pumice, all scoria has a specific gravity greater than 1, and sinks in water. The holes or vesicles form when gases that were dissolved in the magma come out of solution as it erupts, creating bubbles in the molten rock, some of which are frozen in place as the rock cools and solidifies. Scoria may form as part of a lava flow, typically near its surface, or as fragmental ejecta (lapilli, blocks and bombs), for inst ...
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