|
Archipelago Sea
The Archipelago Sea (, ) is a part of the Baltic Sea between the Gulf of Bothnia, the Gulf of Finland and the Sea of Åland, within Finnish territorial waters. By some definitions it contains the List of archipelagos by number of islands, largest archipelago in the world by the number of islands, estimated at around 50,000, although many of the islands are very small and tightly clustered. The larger islands are inhabited and connected by ferries and bridges. Åland, including the largest islands of the region, forms an autonomous region within Finland. The rest of the islands are part of the region of Southwest Finland. The Archipelago Sea is a significant tourist destination. ''The Guardians journalist Tristan Parker wrote an article praising the Turku Archipelago on July 29, 2021, mentioning that "nowhere has the gentle magic of the smaller islands – or their wildlife." Geography and geology The Archipelago Sea covers a roughly triangular area with the cities of Marie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Arctic Archipelago
The Arctic Archipelago, also known as the Canadian Arctic Archipelago, is an archipelago lying to the north of the Canadian continental mainland, excluding Greenland (an autonomous territory of the Danish Realm, which is, by itself, much larger than the combined area of the archipelago) and Iceland (an independent country). Situated in the northern extremity of North America and covering about , this group of 36,563 islands, surrounded by the Arctic Ocean, comprises much of Northern Canada, predominately Nunavut and the Northwest Territories. The archipelago is showing some effects of climate change, with some computer estimates determining that melting there will contribute to the rise in sea levels by 2100. History Around 2500 BCE, the first humans, the Paleo-Eskimos, arrived in the archipelago from the Canadian mainland. Between 1000 and 1500 CE, they were replaced by the Thule people, who are the ancestors of today's Inuit. British claims on the islands, the British A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brändö
Brändö is an island Municipalities of Finland, municipality of Åland, Finland. Characteristics of Brändö are the numerous assembly of islands and islets, most important of which are linked by bridges and causeways. The municipality has a population of () and covers an area of of which is water. The population density is . The municipality is unilingually Swedish language, Swedish and of the population are Finland-Swedish, Swedish speakers. Geography Villages In 1967, Brändö had 12 legally recognized villages ''(henkikirjakylät)'': * Asterholma * Baggholma * Björnholma * Brändö * Fiskö * Hullberga * Jurmo * Korsö * Lappo, Åland, Lappo * Porsskär * Torsholma * Åva Demographics In 2020, 8.9% of the population of Brändö was under the age of 15, 58.1% were aged 15 to 64, and 33.0% were over the age of 65. The average age was 52.2, over the national average of 43.4 and regional average of 43.8. Speakers of Finland Swedish, Swedish made up 71.7% of the popu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrusion
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California. Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained ( phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks. Intrusio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impact Crater
An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Impact craters are typically circular, though they can be elliptical in shape or even irregular due to events such as landslides. Impact craters range in size from microscopic craters seen on lunar rocks returned by the Apollo Program to simple bowl-shaped depressions and vast, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth. Impact craters are the dominant geographic features on many solid Solar System objects including the Moon, Mercury (planet), Mercury, Callisto (moon), Callisto, Ganymede (moon), Ganymede, and most small moons and asteroids. On other planet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumparn
Lumparn (fi. ''Lumpari'') is a large bay devoid of islands in the Fasta Åland, main island of Åland, Finland, bordered by Sund, Åland, Sund to the north, Lumparland to the east, Lemland to the south and Jomala to the west. Description Most of the bay fills a nine kilometer wide impact structure. The structure is estimated to be about 1000 million years old (Proterozoic). The depression was originally believed to be a rift. Extraterrestrial origin was first proposed in 1979, but not until 1993 was the impact structure finally confirmed. Long shatter cones have been discovered in the southwestern part of the bay. The remains of the crater are filled with sediments. Between Pleistocene sediments and crushed rapakivi granite bedrock there is a layer of Paleozoic (Ordovician) limestones. This makes Lumparn one of the few places in Finland where fossils have been found. The bay has also previously been referred to as ''Lumpari'' in some Finnish language, Finnish documents, though th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kvarken
Kvarken ( (as opposed to South Kvarken); ) is the narrow region of the Gulf of Bothnia separating the Bothnian Bay (the inner part of the gulf) from the Bothnian Sea. The distance from the Sweden, Swedish mainland to the Mainland Finland, Finnish mainland is around , while the distance between the outermost islands is only . The water depth in the Kvarken region is only around . The region also has an unusual rate of Post-glacial rebound, land rising at almost a year. Several attempts to cross the strait swimming have been made, but cold water and currents have usually been insurmountable obstacles. The first successful crossing was carried out by Lennart Flygare, Pavio Grzelewski and Tore Klingberg, who on 24 July, 2018, swam from Valassaaret (Valsörarna) on the Finnish side to Holmöarna in Sweden. It took them 12 hours 2 minutes to cross the strait. Kvarken Archipelago On the Finnish side of Kvarken, there is a large archipelago, the Kvarken Archipelago, which includes the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, transports it to another location where it is deposit (geology), deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by Solvation, dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and Wind wave, waves; glacier, glacial Plucking (glaciation), plucking, Abrasion (geology), abrasion, and scour; areal flooding; Aeolian processes, wind abrasion; groundwater processes; and Mass wastin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock (geology)
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the Earth's crust, crust, and most of its interior, except for the liquid Earth's outer core, outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gneiss
Gneiss (pronounced ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. This rock is formed under pressures ranging from 2 to 15 kbar, sometimes even more, and temperatures over 300 °C (572 °F). Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct Cleavage (geology), cleavage. Gneisses are common in the ancient crust of Continental Shield, continental shields. Some of the oldest rocks on Earth are gneisses, such as the Acasta Gneiss. Description image:Orthogneiss Geopark.jpg, Orthogneiss from the Czech Republic In traditional English and North American usage, a gneiss is a coarse-grained metamorphic rock showing compositional banding (gneissic banding) but poorly developed schistosity and indistinct Cleavage (geology), cleavage. In other words, it i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dike (geology), dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or ''granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF diagram, QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) conta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post-glacial Rebound
Post-glacial rebound (also called isostatic rebound or crustal rebound) is the rise of land masses after the removal of the huge weight of ice sheets during the last glacial period, which had caused isostatic depression. Post-glacial rebound and isostatic depression are phases of glacial isostasy (glacial isostatic adjustment, glacioisostasy), the deformation of the Earth's crust in response to changes in ice mass distribution. The direct raising effects of post-glacial rebound are readily apparent in parts of Northern Eurasia, Northern America, Patagonia, and Antarctica. However, through the processes of ''ocean siphoning'' and ''continental levering'', the effects of post-glacial rebound on sea level are felt globally far from the locations of current and former ice sheets.Milne, G.A., and J.X. Mitrovica (2008) ''Searching for eustasy in deglacial sea-level histories.'' Quaternary Science Reviews. 27:2292–2302. Overview During the last glacial period, much of northern Euro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
