Lögberg ( Icelandic pronunciation: [ˈlœɣˌpɛrk] ), or Law Rock , was a rocky outcrop in south west Iceland , at the location for the assembly of the country's Althing parliament . The original Althing was gathered at Þingvellir , an area of dramatic landscapes which was easily accessible from the populated areas of the south west.
68-566: The exact location of the Lögberg is unknown, because of the changing geography of the rift valley over 1000 years. Two possible locations have been identified in Þingvellir, one a flat ledge at the top of a slope named Hallurinn (currently marked by a flagpole), the other in the Almannagjá fault against a rock wall. A site in the Hestagjá ravine has been put forward as ideal. The Lögberg was
136-562: A long history of human habitation. Near the village of Mal'ta, some 160 km northwest of the lake, remains of a young human male known as MA-1 or "Mal'ta Boy" are indications of local habitation by the Mal'ta–Buret' culture ca. 24,000 BP . An early known tribe in the area was the Kurykans . Located in the former northern territory of the Xiongnu confederation, Lake Baikal is one site of
204-545: A number of adjoining subsidiary or co-extensive valleys, which are typically considered part of the principal rift valley geologically. The most extensive rift valley is located along the crest of the mid-ocean ridge system and is the result of sea floor spreading . Examples of this type of rift include the Mid-Atlantic Ridge and the East Pacific Rise . Many existing continental rift valleys are
272-657: A number of years. The lake became the site of the minor engagement between the Czechoslovak legion and the Red Army in 1918. At times during winter freezes, the lake could be crossed on foot, though at risk of frostbite and deadly hypothermia from the cold wind moving unobstructed across flat expanses of ice. In the winter of 1920, the Great Siberian Ice March occurred, when the retreating White Russian Army crossed frozen Lake Baikal. The wind on
340-563: A rich endemic fauna of invertebrates. The copepod Epischura baikalensis is endemic to Lake Baikal and the dominating zooplankton species there, making up 80 to 90% of the total biomass . It is estimated that they filter as much as a thousand cubic kilometers of water a year, or the lake's entire volume every twenty-three years. Among the most diverse invertebrate groups are the amphipod and ostracod crustaceans, freshwater snails , annelid worms and turbellarian worms: More than 350 species and subspecies of amphipods are endemic to
408-413: A rift which results from a leftward discontinuity in the left lateral-moving Dead Sea Transform fault. Where a fault breaks into two strands, or two faults run close to each other, crustal extension may also occur between them, as a result of differences in their motions. Both types of fault-caused extension commonly occur on a small scale, producing such features as sag ponds or landslides . Many of
476-538: A winter minimum of −19 °C (−2 °F) to a summer maximum of 14 °C (57 °F). The region to the east of Lake Baikal is referred to as Transbaikalia or as the Transbaikal, and the loosely defined region around the lake itself is sometimes known as Baikalia . UNESCO declared Baikal a World Heritage Site in 1996. Lake Baikal is in a rift valley, created by the Baikal Rift Zone , where
544-646: Is Lake Baikal. A smaller number of other freshwater annelids is known: 30 species of leeches (Hirudinea), and 4 polychaetes . Several hundred species of nematodes are known from the lake, but a large percentage of these are undescribed . More than 140 endemic flatworm (Plathelminthes) species are in Lake Baikal, where they occur on a wide range of bottom types. Most of the flatworms are predatory, and some are relatively brightly marked. They are often abundant in shallow waters, where they are typically less than 2 cm (1 in) long, but in deeper parts of
612-415: Is a stub . You can help Misplaced Pages by expanding it . Rift valley A rift valley is a linear shaped lowland between several highlands or mountain ranges produced by the action of a geologic rift . Rifts are formed as a result of the pulling apart of the lithosphere due to extensional tectonics . The linear depression may subsequently be further deepened by the forces of erosion. More generally
680-484: Is a center for ostracod diversity. About 90% of the Lake Baikal ostracods are endemic, meaning that there are c. 200 endemic species. This makes it the second-most diverse group of crustacean in the lake, after the amphipods. The vast majority of the Baikal ostracods belong to the families Candonidae (more than 100 described species) and Cytherideidae (about 50 described species), but genetic studies indicate that
748-568: Is a prominent example. Charon's Nostromo Chasma is the first confirmed in the Pluto system, however large chasms up to 950 km wide observed on Charon have also been tentatively interpreted by some as giant rifts, and similar formations have also been noted on Pluto. A recent study suggests a complex system of ancient lunar rift valleys, including Vallis Rheita and Vallis Alpes . The Uranus system also has prominent examples, with large 'chasma' believed to be giant rift valley systems, most notably
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#1732772827485816-509: Is about 50 °C (122 °F) have been found. These are mostly in deep water but locally have also been found in relatively shallow water. They have little effect on the lake's temperature because of its huge volume. Stormy weather on the lake is common, especially during the summer and autumn, and can result in waves as high as 4.5 m (15 ft). Lake Baikal is rich in biodiversity . It hosts more than 1,000 species of plants and 2,500 species of animals based on current knowledge, but
884-416: Is an independent research organization carrying out environmental, educational and research projects at Lake Baikal. In July 2008, Russia sent two small submersibles , Mir-1 and Mir-2 , to descend 1,592 m (5,223 ft) to the bottom of Lake Baikal to conduct geological and biological tests on its unique ecosystem. Although originally reported as being successful, they did not set a world record for
952-400: Is around 200 km. Some tourists may spot a Baikal seal along the route. Local entrepreneurs offer overnight in yurt on ice. The ice season ends in mid-April. Owing to increasing temperatures ice starts to melt and becomes shallow and fragile, especially in places with strong under-ice flows. A range of factors contribute to an increased risk of falling through the ice towards the end of
1020-460: Is believed by planetary geologists to be a large rift system. Some features of Venus, most notably, the 4,000 km Devana Chasma and a part of the western Eistla, and possibly also Alta and Bell Regio have been interpreted by some planetary geologists as rift valleys. Some natural satellites also have prominent rift valleys. The 2,000 km long Ithaca Chasma on Tethys in the Saturn system
1088-416: Is caught, smoked , and then sold widely in markets around the lake. Also, a second endemic whitefish inhabits the lake, C. baicalensis . The Baikal black grayling ( Thymallus baicalensis ), Baikal white grayling ( T. brevipinnis ), and Baikal sturgeon ( Acipenser baerii baicalensis ) are other important species with commercial value. They are also endemic to the Lake Baikal basin. The lake hosts
1156-500: Is lower with more than 30 species; about half of these, all in the families Euglesidae , Pisidiidae , and Sphaeriidae , are endemic (the only other family in the lake is the Unionidae with a single nonendemic species). The endemic bivalves are mainly found in shallows, with few species from deep water. With almost 200 described species, including more than 160 endemics, the center of diversity for aquatic freshwater oligochaetes
1224-678: Is one of the investors, who planned to build three hotels, creating 570 jobs. In 2007, the Russian government declared the Baikal region a special economic zone . A popular resort in Listvyanka is home to the seven-story Hotel Mayak. At the northern part of the lake, Baikalplan (a German NGO) built together with Russians in 2009 the Frolikha Adventure Coastline Track , a 100 km (62 mi)-long long-distance trail as an example for sustainable development of
1292-425: Is prepared by specialists every year and it opens when the ice conditions allow it. In 2015, the ice road to Olkhon was open from 17 February to 23 March. The thickness of the ice on the road is about 60 cm (24 in), maximum capacity allowed – 10 t (9.8 long tons; 11 short tons); it is open to the public from 9 am to 6 pm. The road through the lake is 12 km (7.5 mi) long and it goes from
1360-556: Is the world's seventh-largest lake by surface area, as well as the second largest lake in Eurasia after the Caspian Sea . However, because it is also the deepest lake , with a maximum depth of 1,642 metres (5,387 feet ; 898 fathoms ), Lake Baikal is the world's largest freshwater lake by volume, containing 23,615.39 km (5,670 cu mi) of water or 22–23% of the world's fresh surface water , more than all of
1428-624: The Baikal Deep Underwater Neutrino Telescope (BDUNT). The Baikal Neutrino Telescope NT-200 is being deployed in Lake Baikal, 3.6 km (2.2 mi) from shore at a depth of 1.1 km (0.68 mi). It consists of 192 optical modules. The lake, nicknamed "the Pearl of Siberia", drew investors from the tourist industry as energy revenues sparked an economic boom. Viktor Grigorov's Grand Baikal in Irkutsk
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#17327728274851496-543: The Black Sea . In Lake Baikal, the water temperature varies significantly depending on location, depth, and time of the year. During the winter and spring, the surface freezes for about 4–5 months; from early January to early May–June (latest in the north), the lake surface is covered in ice. On average, the ice reaches a thickness of 0.5 to 1.4 m (1.6–4.6 ft), but in some places with hummocks , it can be more than 2 m (6.6 ft). During this period,
1564-582: The Early Middle Ages , populations of the European bison ( Bison bonasus ) were found near the lake; this represented the easternmost range of the species. There are 236 species of birds that inhabit Lake Baikal, 29 of which are waterfowl . Although named after the lake, both the Baikal teal and Baikal bush warbler are widespread in eastern Asia. Fewer than 65 native fish species occur in
1632-639: The Han–Xiongnu War , where the armies of the Han dynasty pursued and defeated the Xiongnu forces from the second century BC to the first century AD. They recorded that the lake was a "huge sea" ( hanhai ) and designated it the North Sea ( Běihǎi ) of the semimythical Four Seas . The Kurykans, a Siberian tribe who inhabited the area in the sixth century, gave it a name that translates to "much water". Later on, it
1700-492: The North American Great Lakes combined. It is also the world's oldest lake at 25–30 million years, and among the clearest. Lake Baikal is home to thousands of species of plants and animals, many of them endemic to the region. It is also home to Buryat tribes, who raise goats, camels , cattle, sheep , and horses on the eastern side of the lake, where the mean temperature varies from
1768-642: The Primorsky Range stretching along the western shore. The mountains and the taiga are protected as a national park. It contains 27 islands; the largest, Olkhon , is 72 km (45 mi) long and is the third-largest lake-bound island in the world. The lake is fed by as many as 330 inflowing rivers. The main ones draining directly into Baikal are the Selenga , the Barguzin , the Upper Angara ,
1836-730: The Turka , the Sarma , and the Snezhnaya . It is drained through a single outlet, the Angara . Regular winds exist in Baikal's rift valley. Baikal is one of the clearest lakes in the world. During the winter, the water transparency in open sections can be as much as 30–40 m (100–130 ft), but during the summer it is typically 5–8 m (15–25 ft). Baikal is rich in oxygen, even in deep sections, which separates it from distinctly stratified bodies of water such as Lake Tanganyika and
1904-543: The 1492 km long Messina Chasma on Titania, 622 km Kachina Chasmata on Ariel, Verona Rupes on Miranda, and Mommur Chasma on Oberon. Lake Baikal Lake Baikal is the deepest rift lake in the world. It is situated in southern Siberia , Russia between the federal subjects of Irkutsk Oblast to the northwest and the Republic of Buryatia to the southeast. At 31,722 km (12,248 sq mi)—slightly larger than Belgium —Lake Baikal
1972-544: The 1990s provide a detailed record of climatic variation over the past 6.7 million years. Longer and deeper sediment cores are expected in the near future. Lake Baikal is the only confined freshwater lake in which direct and indirect evidence of gas hydrates exists. The lake is surrounded by mountains; the Baikal Mountains on the north shore, the Barguzin Range on the northeastern shore and
2040-587: The Amur country by following the Selenga, Uda, and Khilok Rivers to the future sites of Chita and Nerchinsk . The Trans-Siberian Railway was built between 1896 and 1902. Construction of the scenic railway around the southwestern end of Lake Baikal required 200 bridges and 33 tunnels. Until its completion, a train ferry , the SS Baikal , transported railcars across the lake from Port Baikal to Mysovaya for
2108-590: The Amur country. In 1641, Verkholensk was founded on the upper Lena. In 1643, Kurbat Ivanov went further up the Lena and became the first Russian to see Lake Baikal and Olkhon Island . Half his party under Skorokhodov remained on the lake, reached the Upper Angara at its northern tip, and wintered on the Barguzin River on the northeast side. In 1644, Ivan Pokhabov went up the Angara to Baikal, becoming perhaps
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2176-403: The Angara and arrived at Yeniseysk. Vikhor Savin (1624) and Maksim Perfilyev (1626 and 1627–28) explored Tungus country on the lower Angara. To the west, Krasnoyarsk on the upper Yenisei was founded in 1627. A number of ill-documented expeditions explored eastward from Krasnoyarsk. In 1628, Pyotr Beketov first encountered a group of Buryats and collected yasak ( tribute ) from them at
2244-505: The Earth's crust is slowly pulling apart. At 636 km (395 mi) long and 79 km (49 mi) wide, Lake Baikal has the largest surface area of any freshwater lake in Asia, at 31,722 km (12,248 sq mi), and is the deepest lake in the world at 1,642 metres (5,387 feet; 898 fathoms). The surface of the lake is 455.5 m (1,494 ft) above sea level, while the bottom of
2312-630: The actual figures for both groups are believed to be significantly higher. More than 80% of the animals are endemic . The watershed of Lake Baikal has numerous floral species represented. The marsh thistle ( Cirsium palustre ) is found here at the eastern limit of its geographic range. Submerged macrophytic vascular plants are mostly absent, except in some shallow bays along the shores of Lake Baikal. More than 85 species of submerged macrophytes have been recorded, including genera such as Ceratophyllum , Myriophyllum , Potamogeton , and Sparganium . The invasive species Elodea canadensis
2380-427: The area and notable earthquakes happen every few years. The lake is divided into three basins: North, Central, and South, with depths about 900 m (3,000 ft), 1,600 m (5,200 ft), and 1,400 m (4,600 ft), respectively. Fault-controlled accommodation zones rising to depths about 300 m (980 ft) separate the basins. The North and Central basins are separated by Academician Ridge , while
2448-788: The area around the Selenga Delta and the Buguldeika Saddle separates the Central and South basins. The lake drains into the Angara , a tributary of the Yenisey . Landforms include Cape Ryty on Baikal's northwest coast. Baikal's age is estimated at 25–30 million years, making it the most ancient lake in geological history. It is unique among large, high-latitude lakes, as its sediments have not been scoured by overriding continental ice sheets. Russian, U.S., and Japanese cooperative studies of deep-drilling core sediments in
2516-500: The deepest freshwater dive, reaching a depth of only 1,580 m (5,180 ft). That record is currently held by Anatoly Sagalevich , at 1,637 m (5,371 ft) (also in Lake Baikal aboard a Pisces submersible in 1990). Russian scientist and federal politician Artur Chilingarov , the leader of the mission, took part in the Mir dives as did Russian president Vladimir Putin . Since 1993, neutrino research has been conducted at
2584-405: The deepest living freshwater fish in the world, occurring near the bottom of Lake Baikal. The golomyankas are the primary prey of the Baikal seal and represent the largest fish biomass in the lake. Beyond members of Cottoidea, there are few endemic fish species in the lake basin. The most important local species for fisheries is the omul ( Coregonus migratorius ), an endemic whitefish . It
2652-679: The exposed lake was so cold, many people died, freezing in place until spring thaw. Beginning in 1956, the impounding of the Irkutsk Dam on the Angara River raised the level of the lake by 1.4 m (4.6 ft). As the railway was built, a large hydrogeographical expedition headed by F.K. Drizhenko produced the first detailed contour map of the lake bed. Several organizations are carrying out natural research projects on Lake Baikal. Most of them are governmental or associated with governmental organizations. The Baikalian Research Centre
2720-470: The family Asellidae . There are four species of the genus Baicalasellus , and the two species Mesoasellus dybowskii and Limnoasellus poberezhnii. These six endemic species are found on rocky substrata in depths varying from 3–10 meters (Baicalasellus angarensis) to more than hundred meters (Mesoasellus dybowskii). There are about 60 known species of cladocerans (water fleas), several of them endemic. Similar to another ancient lake, Tanganyika , Baikal
2788-468: The figures of ice that are formed at rocky banks of Olkhon Island , including Cape Hoboy, the Three Brothers rock, and caves to the north of Khuzhir . It also provides access to small islands like Ogoy Island and Zamogoy. The ice itself has a transparency of one meter depth. That is why this season is popular for hiking, ice-walking, ice-skating, and bicycle riding. An ice route around Olkhon
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2856-415: The first Russian to use this route, which is difficult because of the rapids. He crossed the lake and explored the lower Selenge River . About 1647, he repeated the trip, obtained guides, and visited a 'Tsetsen Khan' near Ulan Bator . In 1648, Ivan Galkin built an ostrog on the Barguzin River which became a center for eastward expansion. In 1652, Vasily Kolesnikov reported from Barguzin that one could reach
2924-467: The future site of Bratsk . In 1629, Yakov Khripunov set off from Tomsk to find a rumored silver mine. His men soon began plundering both Russians and natives. They were joined by another band of rioters from Krasnoyarsk, but left the Buryat country when they ran short of food. This made it difficult for other Russians to enter the area. In 1631, Maksim Perfilyev built an ostrog at Bratsk. The pacification
2992-400: The high level of dissolved oxygen in the lake. Among the "giants" are several species of spiny Acanthogammarus and Brachyuropus ( Acanthogammaridae ) found at both shallow and deep depths. These conspicuous and common amphipods are essentially carnivores (will also take detritus ), and can reach a body length up to 7 cm (2.8 in). The number of isopods is low; they belong to
3060-434: The lake are Listvyanka village, Olkhon Island, Kotelnikovsky cape, Baykalskiy Priboi, resort Khakusy and Turka village. The popularity of Lake Baikal is growing from year to year, but there is no developed infrastructure in the area. For the quality of service and comfort from the visitor's point of view, Lake Baikal still has a long way to go. The ice road to Olkhon Island is the only legal ice road on Lake Baikal. The route
3128-710: The lake basin, but more than half of these are endemic. The families Abyssocottidae (deep-water sculpins), Comephoridae (golomyankas or Baikal oilfish), and Cottocomephoridae (Baikal sculpins) are entirely restricted to the lake basin. All these are part of the Cottoidea and are typically less than 20 cm (8 in) long. Of particular note are the two species of golomyanka ( Comephorus baicalensis and C. dybowskii ). These long-finned, translucent fish typically live in open water at depths of 100–500 m (330–1,640 ft), but occur both shallower and much deeper. Together with certain abyssocottid sculpins, they are
3196-428: The lake is 1,186.5 m (3,893 ft; 648.8 fathoms) below sea level, and below this lies some 7 km (4.3 mi) of sediment , placing the rift floor some 8–11 km (5.0–6.8 mi) below the surface, the deepest continental rift on Earth. In geological terms, the rift is young and active – it widens about 4 mm (0.16 in) per year. The fault zone is also seismically active; hot springs occur in
3264-908: The lake, and about half of these are endemic to Baikal; however, significant taxonomic uncertainties remain for this group. The Baikal seal or nerpa ( Pusa sibirica ) is endemic to Lake Baikal. A wide range of land mammals can be found in the habitats around the lake, such as the brown bear ( Ursus arctos ), Eurasian wolf ( Canis lupus lupus ), red fox ( Vulpes vulpes ), sable ( Martes zibellina ), stoat ( Mustela erminea ), Eurasian otter ( Lutra lutra ), snow leopard ( Panthera uncia ), moose ( Alces alces ), elk ( Cervus canadensis ), reindeer ( Rangifer tarandus ), Siberian roe deer ( Capreolus pygargus ), Siberian musk deer ( (Moschus moschiferus ), wild boar ( Sus scrofa ), red squirrel ( Sciurus vulgaris ), Siberian chipmunk ( Eutamias sibiricus ), marmots ( Marmota sp.), lemmings ( Lemmus sp.), and mountain hare ( Lepus timidus ). Until
3332-615: The lake, the largest, Baikaloplana valida , can reach up to 30 cm (1 ft) when outstretched. At least 18 species of sponges occur in the lake, including about 15 species from the endemic family Lubomirskiidae (the remaining are from the nonendemic family Spongillidae ), which colonized the lake about 3.4 million years ago. The lake's sponges makes up around 44% of the benthic animal biomass. Lubomirskia baicalensis , Baikalospongia bacillifera , and B. intermedia are unusually large for freshwater sponges and can reach 1 m (3.3 ft) or more. These three are also
3400-473: The lake. They are exceptionally diverse in ecology and appearance, ranging from the pelagic Macrohectopus to the relatively large deep-water Abyssogammarus and Garjajewia , the tiny herbivorous Micruropus , and the parasitic Pachyschesis (parasitic on other amphipods ). The "gigantism" of some Baikal amphipods, which has been compared to that seen in Antarctic amphipods, has been linked to
3468-677: The largest freshwater lake by area, lies in the ancient and dormant Midcontinent Rift . The largest subglacial lake, Lake Vostok , may also lie in an ancient rift valley. Lake Nipissing and Lake Timiskaming in Ontario and Quebec , Canada lie inside a rift valley called the Ottawa-Bonnechere Graben . Þingvallavatn , Iceland's largest natural lake, is also an example of a rift lake. Rift valleys are also known to occur on other terrestrial planets and natural satellites. The 4,000 km long Valles Marineris on Mars
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#17327728274853536-407: The majority mainly live at shallower depths. About 30 freshwater snail species can be seen deeper than 100 m (330 ft), which represents the approximate limit of the sunlight zone , but only 10 are truly deepwater species. In general, Baikal snails are thin-shelled and small. Two of the most common species are Benedictia baicalensis and Megalovalvata baicalensis . Bivalve diversity
3604-500: The most common sponges in the lake. While the Baikalospongia species typically have encrusting or carpet-like structures, L. baikalensis often has branching structures and in areas where common may form underwater "forests". Most sponges in the lake are typically green when alive because of symbiotic chlorophytes ( zoochlorella ), but can also be brownish or yellowish. The Baikal area, sometimes known as Baikalia , has
3672-748: The place on which the Lawspeaker ( lögsögumaður [ˈlœɣˌsœːɣʏˌmaːðʏr̥] ) took his seat as the presiding official of the assembly of the Althing . Speeches and announcements were made from the spot. Anyone attending could make their argument from the Lögberg. The gatherings were also convened and dissolved from it. The Lögberg performed its purpose from the formation of the parliament in 930. It ceased to be used in 1262, when Iceland took allegiance to Norway . 64°15′35″N 21°07′22″W / 64.2596°N 21.1227°W / 64.2596; -21.1227 This Iceland location article
3740-640: The region. Baikal was also declared a UNESCO World Heritage site in 1996. Rosatom plans to build a laboratory near Baikal, in conjunction with an international uranium plant and to invest $ 2.5 billion in the region and create 2,000 jobs in the city of Angarsk . Lake Baikal is a popular destination among tourists from all over the world. According to the Russian Federal State Statistics Service, in 2013, 79,179 foreign tourists visited Irkutsk and Lake Baikal; in 2014, 146,937 visitors. The most popular places to stay by
3808-629: The result of a failed arm ( aulacogen ) of a triple junction , although there are three, the East African Rift , Rio Grande rift and the Baikal Rift Zone , which are currently active, as well as a fourth which may be, the West Antarctic Rift System . In these instances, not only the crust but entire tectonic plates are in the process of breaking apart forming new plates. If they continue, continental rifts will eventually become oceanic rifts. Other rift valleys are
3876-475: The result of bends or discontinuities in horizontally-moving (strike-slip) faults. When these bends or discontinuities are in the same direction as the relative motions along the fault, extension occurs. For example, for a right lateral-moving fault, a bend to the right will result in stretching and consequent subsidence in the area of the irregularity. In the view of many geologists today, the Dead Sea lies in
3944-508: The surface layer, and at the peak in August can reach up to about 16 °C (61 °F) in the main sections and 20–24 °C (68–75 °F) in shallow bays in the southern half of the lake. During this time, the pattern is inverted compared to the winter and spring, as the water temperature falls with increasing depth. As the autumn begins, the surface temperature falls again and a second homothermic period at around 4 °C (39 °F) of
4012-554: The temperature slowly increases with depth in the lake, being coldest near the ice-covered surface at around freezing, and reaching about 3.5–3.8 °C (38.3–38.8 °F) at a depth of 200–250 m (660–820 ft). After the surface ice breaks up, the surface water is slowly warmed up by the sun, and in May–June, the upper 300 m (980 ft) or so becomes homothermic (same temperature throughout) at around 4 °C (39 °F) because of water mixing. The sun continues to heat up
4080-612: The true diversity in at least the latter family has been heavily underestimated. The morphology of the Baikal ostracods is highly diverse. As of 2006 , almost 150 freshwater snails are known from Lake Baikal, including 117 endemic species from the subfamilies Baicaliinae (part of the Amnicolidae ) and Benedictiinae (part of the Lithoglyphidae ), and the families Planorbidae and Valvatidae . All endemics have been recorded between 20 and 30 m (66 and 98 ft), but
4148-524: The upper circa 300 m (980 ft) occurs in October–November. In the deepest parts of the lake, from about 300 m (980 ft), the temperature is stable at 3.1–3.4 °C (37.6–38.1 °F) with only minor annual variations. The average surface temperature has risen by almost 1.5 °C (2.7 °F) in the last 50 years, resulting in a shorter period where the lake is covered by ice. At some locations, hydrothermal vents with water that
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#17327728274854216-403: The valley is likely to be filled with sedimentary deposits derived from the rift flanks and the surrounding areas. In many cases rift lakes are formed. One of the best known examples of this process is the East African Rift . On Earth, rifts can occur at all elevations, from the sea floor to plateaus and mountain ranges in continental crust or in oceanic crust . They are often associated with
4284-504: The village Kurkut on the mainland to Irkutskaya Guba on Olkhon Island. Baikal has a number of different tourist activities, depending on the season. Generally, Baikal has two top tourist seasons. The first season is ice season, which starts usually in mid-January and lasts till mid-April. During this season ice depth increases up to 140 centimeters, that allows safe vehicle driving on the ice cover (except heavy vehicles, such as tourist buses, that do not take this risk). This allows access to
4352-611: The world's largest lakes are located in rift valleys. Lake Baikal in Siberia , a World Heritage Site , lies in an active rift valley. Baikal is both the deepest lake in the world and, with 20% of all of the liquid freshwater on earth, has the greatest volume. Lake Tanganyika , second by both measures, is in the Albertine Rift , the westernmost arm of the active East African Rift . Lake Superior in North America ,
4420-670: Was called "natural lake" ( Baygal nuur ) by the Buryats and "rich lake" ( Bay göl ) by the Yakuts. Little was known to Europeans about the lake until Russia expanded into the area in the 1600s. The first Russian explorer to reach Lake Baikal was Kurbat Ivanov in 1643. Lake Baikal was under the Anbei Protectorate of the Tang dynasty from 647 CE to 682 CE. Russian expansion into the Buryat area around Lake Baikal in 1628–1658
4488-529: Was introduced to the lake in the 1950s. Instead of vascular plants, aquatic flora is often dominated by several green algae species, notably Draparnaldioides , Tetraspora , and Ulothrix in water shallower than 20 m (65 ft); although Aegagrophila , Cladophora , and Draparnaldioides may occur deeper than 30 m (100 ft). Except for Ulothrix , there are endemic Baikal species in all these green algae genera. More than 400 diatom species, both benthic and planktonic , are found in
4556-608: Was moderately successful, but in 1634, Bratsk was destroyed and its garrison killed. In 1635, Bratsk was restored by a punitive expedition under Radukovskii. In 1638, it was besieged unsuccessfully. In 1638, Perfilyev crossed from the Angara over the Ilim portage to the Lena River and went downstream as far as Olyokminsk . Returning, he sailed up the Vitim River into the area east of Lake Baikal (1640) where he heard reports of
4624-517: Was part of the Russian conquest of Siberia . It was done first by following the Angara River upstream from Yeniseysk (founded 1619) and later by moving south from the Lena River. Russians first heard of the Buryats in 1609 at Tomsk. According to folktales related a century after the fact, in 1623, Demid Pyanda , who may have been the first Russian to reach the Lena, crossed from the upper Lena to
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