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Paleoshoreline
A paleoshoreline (ancient shoreline) is a shoreline which existed in the geologic past. (''Paleo'' is from an ancient Greek word meaning "old" or "ancient".) A perched coastline is an ancient (fossil) shoreline positioned above the present shoreline. Tides cause the ocean to advance and recede in a very short time scale, in most places about twice per day; weather conditions can also cause short-term variations. Coastlines can also move due to coastal erosion, without a change in sea level. But "sea level" refers to the average level over a relatively long period (years). This average sea level can advance and recede over much longer periods (thousands or millions of years), causing paleoshorelines which may be difficult to identify. Just off the coast of parts of North America, in the last 15,000 years sea level has varied from over below, to as high as above its present level. That entire time, humans have lived in North America. A lake may also have a paleoshoreline. Pal ...
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Palaeochannel
A palaeochannel, also spelt paleochannel and also known as palaeovalley or palaeoriver, is a geological term describing a remnant of an inactive river or stream channel that has been filled or buried by younger sediment. The sediments that the ancient channel is cut into or buried by can be unconsolidated, semi-consolidated, consolidated or Diagenesis, lithified. The word ''palaeochannel'' is formed from the ''palaeo'', meaning "old," and ''channel''. Recognition A palaeochannel is distinct from the overbank deposits of currently-active river channels, including ephemeral water courses that do not regularly flow (such as the Todd River, Central Australia) because the river bed is filled with sedimentary deposits unrelated to the normal bed load of the current drainage pattern. Many palaeochannels are arranged on old drainage patterns, distinct from the current drainage system of a catchment. For example, palaeochannels may relate to a system of rivers and creeks that drained ...
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Beringia Land Bridge-noaagov
Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of the Kamchatka Peninsula. It includes the Chukchi Sea, the Bering Sea, the Bering Strait, the Chukchi Peninsula, Chukchi and Kamchatka Peninsulas in Russia as well as Alaska in the United States and the Yukon in Canada. The area includes land lying on the North American Plate and Siberian land east of the Chersky Range. At certain times in prehistory, it formed a land bridge that was up to wide at its greatest extent and which covered an area as large as British Columbia and Alberta together, totaling approximately . Today, the only land that is visible from the central part of the Bering land bridge are the Diomede Islands, the Pribilof Islands of St. Paul and St. George, St. Lawrence Island, St. Matthew Island, and King Island (Alaska), ...
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Doggerland
Doggerland was an area of land, now submerged beneath the North Sea, that connected Britain to continental Europe. It was flooded by rising sea levels around 6500–6200 BCE. The flooded land is known as the Dogger Littoral. Geological surveys have suggested that it stretched from what is now the east coast of Great Britain to what are now the Netherlands, the western coast of Germany and the Danish peninsula of Jutland. It was probably a rich habitat with human habitation in the Mesolithic period,Patterson, W, "Coastal Catastrophe" (paleoclimate research document), University of Saskatchewan
although rising sea levels gradually reduced it to low-lying islands before its final submergence, possibly following a ts ...
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Bering Land Bridge
Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of the Kamchatka Peninsula. It includes the Chukchi Sea, the Bering Sea, the Bering Strait, the Chukchi Peninsula, Chukchi and Kamchatka Peninsulas in Russia as well as Alaska in the United States and the Yukon in Canada. The area includes land lying on the North American Plate and Siberian land east of the Chersky Range. At certain times in prehistory, it formed a land bridge that was up to wide at its greatest extent and which covered an area as large as British Columbia and Alberta together, totaling approximately . Today, the only land that is visible from the central part of the Bering land bridge are the Diomede Islands, the Pribilof Islands of St. Paul and St. George, St. Lawrence Island, St. Matthew Island, and King Island (Alaska), ...
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Perched Coastline
A perched coastline is a fossil coastline currently above the present coastline. It can be produced by one of two factors: * Higher sea levels in the past than today. For example, during the last ice age interglacial period, climates were significantly warmer than today, and thermal expansion of the oceans, together with increased melting of glaciers, meant that sea levels were higher than they are today. This has created evidence of perched coastlines all around the world. * Through coastal uplift from local geological processes, particularly along the edges of rift valleys or subduction zones of tectonic plates. This second kind of perched coastline is important archaeologically, as it can expose human remains that would otherwise be below sea level. See also * Paleoshoreline A paleoshoreline (ancient shoreline) is a shoreline which existed in the geologic past. (''Paleo'' is from an ancient Greek word meaning "old" or "ancient".) A perched coastline is an ancient (fo ...
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North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian Sea in the north. It is more than long and wide, covering . It hosts key north European shipping lanes and is a major fishery. The coast is a popular destination for recreation and tourism in bordering countries, and a rich source of energy resources, including wind and wave power. The North Sea has featured prominently in geopolitical and military affairs, particularly in Northern Europe, from the Middle Ages to the modern era. It was also important globally through the power northern Europeans projected worldwide during much of the Middle Ages and into the modern era. The North Sea was the centre of the Vikings' rise. The Hanseatic League, the Dutch Republic, and the British each sought to gain command of the North Sea and access t ...
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List Of Prehistoric Lakes
This a partial list of prehistoric lakes. Although the form of the names below differ, the lists are alphabetized by the identifying name of the lake (e.g., Algonquin for Glacial Lake Algonquin). YBP = Years Before Present. North America Endorheic basins * Estancia Valley, Central New Mexico, United States ** Lake Estancia, glacial paleolake that once hosted cutthroat trout * Plains of San Agustín, Central New Mexico, United States ** Lake San Agustín, present day site of the Very Large Array * Tularosa basin, Southern New Mexico, United States ** Lake Otero ** Lake Lucero; Once much larger, the present day lake is an alkali lake and the main source of gypsum for White Sands National Park, the largest gypsum dune field in the world. * Great Basin ** Mono Lake Lee Vining, California. Rapidly shrinking due to Los Angeles Department of Water and Power damming tributaries. Atlantic Drainage * St. Lawrence River drainage, i.e., the Great Lakes ** Champlain Sea; 11,800 – 8, ...
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List Of Ancient Oceans
This is a list of former oceans that disappeared due to tectonic movements and other geographical and climatic changes. In alphabetic order: List * Bridge River Ocean, the ocean between the ancient Insular Islands (that is, Stikinia) and North America * Cache Creek Ocean, a Paleozoic ocean between the Wrangellia Superterrane and Yukon-Tanana Terrane * Iapetus Ocean, the Southern hemisphere ocean between Baltica and Avalonia * Kahiltna-Nutotzin Ocean, Mesozoic * Khanty Ocean, the Precambrian to Silurian ocean between Baltica and the Siberian continent * Medicine Hat Ocean * Mezcalera Ocean, the ocean between the Guerrero Terrane and Laurentia * Mirovia, the ocean that surrounded the Rodinia supercontinent * Mongol-Okhotsk Ocean, the early Mesozoic ocean between the North China and Siberia cratons * Oimyakon Ocean, the northernmost part of the Mesozoic Panthalassa Ocean * Paleo-Tethys Ocean, the ocean between Gondwana and the Hunic terranes * Pan-African Ocean, the ocean th ...
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Ryukyu Islands
The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yonaguni the westernmost. The larger are mostly high islands and the smaller mostly coral. The largest is Okinawa Island. The climate of the islands ranges from humid subtropical climate (Köppen climate classification ''Cfa'') in the north to tropical rainforest climate (Köppen climate classification ''Af'') in the south. Precipitation is very high and is affected by the rainy season and typhoons. Except the outlying Daitō Islands, the island chain has two major geologic boundaries, the Tokara Strait (between the Tokara and Amami Islands) and the Kerama Gap (between the Okinawa and Miyako Islands). The islands beyond the Tokara Strait are characterized by their coral reefs. The Ōsumi and Tokara Islands, the northernmost of the islands, fall un ...
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Yonaguni Monument
The , also known as , is a submerged rock formation off the coast of Yonaguni, the southernmost of the Ryukyu Islands, in Japan. It lies approximately a hundred kilometres east of Taiwan. Marine geologist Masaaki Kimura claims that the formations are man-made stepped monoliths. These claims have been described as pseudoarchaeological. Neither the Japanese Agency for Cultural Affairs nor the government of Okinawa Prefecture recognise the features as important cultural artifacts and neither government agency has carried out research or preservation work on the site. Discovery The sea off Yonaguni is a popular diving location during the winter months because of its large population of hammerhead sharks. In 1986, while looking for a good place to observe the sharks, Kihachiro Aratake, a director of the Yonaguni-Cho Tourism Association, noticed some singular seabed formations resembling architectural structures. Shortly thereafter, a group of scientists directed by Masaaki Kimur ...
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California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territories of the United States by population, most populous U.S. state and the List of U.S. states and territories by area, 3rd largest by area. It is also the most populated Administrative division, subnational entity in North America and the 34th most populous in the world. The Greater Los Angeles area and the San Francisco Bay Area are the nation's second and fifth most populous Statistical area (United States), urban regions respectively, with the former having more than 18.7million residents and the latter having over 9.6million. Sacramento, California, Sacramento is the state's capital, while Los Angeles is the List of largest California cities by population, most populous city in the state and the List of United States cities by population, ...
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Oregon
Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of its eastern boundary with Idaho. The 42nd parallel north, 42° north parallel delineates the southern boundary with California and Nevada. Oregon has been home to many Indigenous peoples of the Americas, indigenous nations for thousands of years. The first European traders, explorers, and settlers began exploring what is now Oregon's Pacific coast in the early-mid 16th century. As early as 1564, the Spanish expeditions to the Pacific Northwest, Spanish began sending vessels northeast from the Philippines, riding the Kuroshio Current in a sweeping circular route across the northern part of the Pacific. In 1592, Juan de Fuca undertook detailed mapping and studies of ocean currents in the Pacific Northwest, including the Oregon coast as well as ...
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