|
West Siberian Glacial Lake
The West Siberian Glacial Lake, also known as West Siberian Lake (russian: Западно-Сибирское море) or Mansiyskoe Lake (russian: Мансийское озеро), was a periglacial lake formed when the Arctic Ocean outlets for each of the Ob and Yenisei rivers were blocked by the Barents-Kara Ice Sheet during the Weichselian Glaciation, approximately 80,000 years ago. It was situated on the West Siberian Plain, and at its maximum extent the lake's surface area was more than 750,000 km2 which is more than twice that of the present-day Caspian Sea. It is theorized that although drainage to the Arctic Ocean basin (e.g. by the Ob and Yenisei Rivers) was prevented, the lake would eventually overflow to the Mediterranean Sea through a circuitous route that would include the Aral Sea, the Caspian Sea, and the Black Sea. This would have resulted in water from the Selenga River and Lake Baikal draining over a course of some , considerably longer than any river' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Age Glacial Lakes Of Siberia And Central Asia - Ru
Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color. In the Solar System, ice is abundant and occurs naturally from as close to the Sun as Mercury to as far away as the Oort cloud objects. Beyond the Solar System, it occurs as interstellar ice. It is abundant on Earth's surfaceparticularly in the polar regions and above the snow lineand, as a common form of precipitation and deposition, plays a key role in Earth's water cycle and climate. It falls as snowflakes and hail or occurs as frost, icicles or ice spikes and aggregates from snow as glaciers and ice sheets. Ice exhibits at least eighteen phases ( packing geometries), depending on temperature and pressure. When water is cooled rapidly (quenching), up to three types of amorphous ice can form depending on it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kiloannum
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (the mean yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glaciology
Glaciology (; ) is the scientific study of glaciers, or more generally ice and natural phenomena that involve ice. Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, climatology, meteorology, hydrology, biology, and ecology. The impact of glaciers on people includes the fields of human geography and anthropology. The discoveries of water ice on the Moon, Mars, Europa and Pluto add an extraterrestrial component to the field, which is referred to as "astroglaciology". Overview A glacier is an extended mass of ice formed from snow falling and accumulating over a long period of time; glaciers move very slowly, either descending from high mountains, as in valley glaciers, or moving outward from centers of accumulation, as in continental glaciers. Areas of study within glaciology include glacial history and the reconstruction of past glaciation. A glaciologist is a person who studies glaciers. A glacia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Former Lakes Of Asia
A former is an object, such as a template, gauge or cutting die, which is used to form something such as a boat's hull. Typically, a former gives shape to a structure that may have complex curvature. A former may become an integral part of the finished structure, as in an aircraft fuselage, or it may be removable, being using in the construction process and then discarded or re-used. Aircraft formers Formers are used in the construction of aircraft fuselage, of which a typical fuselage has a series from the nose to the empennage, typically perpendicular to the longitudinal axis of the aircraft. The primary purpose of formers is to establish the shape of the fuselage and reduce the column length of stringers to prevent instability. Formers are typically attached to longerons, which support the skin of the aircraft. The "former-and-longeron" technique (also called stations and stringers) was adopted from boat construction, and was typical of light aircraft built until the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratethys
The Paratethys sea, Paratethys ocean, Paratethys realm or just Paratethys was a large shallow inland sea that stretched from the region north of the Alps over Central Europe to the Aral Sea in Central Asia. Paratethys was peculiar due to its paleogeography: it consisted of a series of deep basins, formed during the Oxfordian stage of the Late Jurassic as an extension of the rift that formed the Central Atlantic Ocean. These basins were connected with each other and the global ocean by narrow and shallow seaways that often limited water exchange and caused widespread long-term anoxia. Paratethys was at times reconnected with the Tethys or its successors (the Mediterranean Sea or the Indian Ocean) during the Oligocene and the early and middle Miocene times, but at the onset of the late Miocene epoch, the tectonically trapped sea turned into a megalake from the eastern Alps to what is now Kazakhstan. From the Pliocene epoch onward (after 5 million years ago), Paratethys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethys Sea
The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean that covered most of the Earth during much of the Mesozoic Era and early Cenozoic Era, located between the ancient continents of Gondwana and Laurasia, before the opening of the Indian and Atlantic oceans during the Cretaceous Period. It was preceded by the Paleo-Tethys Ocean, which lasted between the Cambrian and the Early Triassic, while the Neotethys formed during the Late Triassic and lasted until the early Eocene (about 50 million years ago) when it completely closed. A portion known as the Paratethys formed during the Late Jurassic, was isolated during the Oligocene (34 million years ago) and lasted up to the Pliocene (about 5 million years ago), when it largely dried out. Many major seas and lakes of Europe and Western Asia, including the Mediterranean Sea, the Black Sea, the Caspian Sea, and the Aral Sea are thought to be remnants of the Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turgai Sea
The Turgai Sea, also known as the Turgay Sea, Turgai Strait, Obik Sea, Ural Sea or West Siberian Sea, was a large shallow body of salt water (an epicontinental or epeiric sea) during the Mesozoic through Cenozoic Eras. It extended north of the present-day Caspian Sea to the "paleo-Arctic" region, and was in existence from the Middle Jurassic to Oligocene, approximately 160 to 29 million years ago. The Turgai Sea was not absolutely continuous throughout this entire era, though it was a persistent and predominating feature in its region; it "fragmented southern Europe and southwestern Asia into many large islands, and separated Europe from Asia." The division of the Eurasian landmass by the Turgai Sea had the effect of isolating animal populations. One of the better known groups are the ceratopsian dinosaurs during the Cretaceous Period, which were restricted to Asia and western North America that were connected for much of the era. The existence of the Turgai Sea also restricte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caspian Seal
The Caspian seal (''Pusa caspica'', syn. ''Phoca caspica'') is one of the smallest members of the earless seal family and unique in that it is found exclusively in the brackish Caspian Sea. It lives along the shorelines, but also on the many rocky islands and floating blocks of ice that dot the Caspian Sea. In winter and cooler parts of the spring and autumn season, it populates the northern Caspian coastline. As the ice melts in the summer and warmer parts of the spring and autumn season, it also occurs in the deltas of the Volga and Ural Rivers, as well as the southern latitudes of the Caspian where the water is cooler due to greater depth. Evidence suggests the seals are descended from Arctic ringed seals that reached the area from the north during an earlier part of the Quaternary period and became isolated in the landlocked Caspian Sea when continental ice sheets melted. Description Adults are about in length. Males are longer than females at an early age, but females ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Seal
The freshwater seals are seals which live in freshwater bodies. The only exclusively freshwater seal species is the Baikal seal, locally named (). The others are the subspecies or colonies of regular saltwater seals. These include two subspecies of ringed seal: the Ladoga seal and the Saimaa ringed seal. Common seals (harbor seals) are known to enter estuaries and freshwater rivers in pursuit of their prey. Colonies of common seals live in some lakes, such as seals of Iliamna Lake, Alaska, trapped there a long time ago. There is also a subspecies called the Ungava seal (''Phoca vitulina mellonae'') that comprises less than 300 individuals landlocked in the fresh water of Lacs des Loups Marins, Petit Lac de Loups Marins, and Lac Bourdel in northern Quebec. California sea lions can also live in fresh water for periods of time, such as near Bonneville Dam, nearly up the Columbia River. In 2004, a healthy sea lion was found sitting on a road in Merced County, California, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baikal Seal
The Baikal seal, Lake Baikal seal or (''Pusa sibirica''), is a species of earless seal endemic to Lake Baikal in Siberia, Russia. Like the Caspian seal, it is related to the Arctic ringed seal. The Baikal seal is one of the smallest true seals and the only exclusively freshwater pinniped species.Randall R. Reeves, Brent S. Stewart, Phillip J. clapham, James A. Powell, ''"National Audubon Society Guide to the Marine Mammals of the World"'', Alfred A. Knopf publishing, New York, 2002 A subpopulation of inland harbour seals living in the Hudson Bay region of Quebec, Canada ( Lacs des Loups Marins harbour seals), as well as the Saimaa ringed seal and the Ladoga seal (both ringed seal subspecies), are also found in fresh water, but these seals are part of species that also have marine populations. The most recent population estimates are 80,000 to 100,000 animals, roughly equaling the expected carrying capacity of the lake. At present, the species is not considered threatened. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
