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30-404: Phayao Lake began from the collapse of the lithosphere about 70 million years ago. This area was surrounded by low mountains before. There are 18 creeks mixing together here. In 1935, the department of fisheries had set up Phayao inland fisheries station on Ing River and made the dam, which cause a large swamp with a depth of 1.5 metres. “Nong Lang” was one of the most prominent ponds. The land at

60-411: A family of catfish that are native to Africa ( Bagrus ) and Asia (all other genera) from Japan to Borneo . It includes about 245 species. These fish are commonly known as naked catfishes or bagrid catfishes . Many large bagrids are important as a source of food. Some species are also kept as aquarium fishes. The dorsal fin is preceded by a spine. The adipose fin is present and can have

90-408: A relatively long base in some species. The pectoral fin spine can be serrated. The body is completely naked (they have no scales). The maximum length is about 1.5 m (4.9 ft). Fishes of the family Bagridae have four pairs of well-developed barbels covered by a layer of taste bud -enriched epithelium . The taxonomy of this family has changed rapidly. Nelson (2006) comments how "the family

120-805: A subduction zone cannot subduct much further than about 100 km (62 mi) before resurfacing. As a result, continental lithosphere is not recycled at subduction zones the way oceanic lithosphere is recycled. Instead, continental lithosphere is a nearly permanent feature of the Earth. Geoscientists can directly study the nature of the subcontinental mantle by examining mantle xenoliths brought up in kimberlite , lamproite , and other volcanic pipes . The histories of these xenoliths have been investigated by many methods, including analyses of abundances of isotopes of osmium and rhenium . Such studies have confirmed that mantle lithospheres below some cratons have persisted for periods in excess of 3 billion years, despite

150-415: Is a thermal boundary layer for the convection in the mantle. The thickness of the mantle part of the oceanic lithosphere can be approximated as a thermal boundary layer that thickens as the square root of time. h ∼ 2 κ t {\displaystyle h\,\sim \,2\,{\sqrt {\kappa t}}} Here, h {\displaystyle h} is the thickness of

180-692: Is approximately 159 kilograms. Humidity in the area ranges from 70 to 80 percent. The estimated mass of fish harvest per hectare is approximately 159 kilograms. There are about 50 species of fish: Iridescent shark (ปลาสวาย), cyprinid , common carp (ปลาไน), nile tilapia (ปลานิล), climbing perch (ปลาหมอ), striped snakehead (ปลาช่อน), great white sheatfish (ปลาค้าวขาว), bagrid catfishes (ปลากด), clarias catfish (ปลาดุก), asian swamp eel (ปลาไหลนา), spotted featherback (ปลากราย), snake skin gourami (ปลาสลิด), moonlight gourami (ปลากระดี่นาง), minnow (ปลาซิว) There are water hyacinths (ผักตบชวา), different types of grasses, duckweed, seaweed, lotus, and

210-417: Is no thicker than the crust, but oceanic lithosphere thickens as it ages and moves away from the mid-ocean ridge. The oldest oceanic lithosphere is typically about 140 kilometres (87 mi) thick. This thickening occurs by conductive cooling, which converts hot asthenosphere into lithospheric mantle and causes the oceanic lithosphere to become increasingly thick and dense with age. In fact, oceanic lithosphere

240-409: Is rich in natural resources that aid in providing the people of Phayao with a relatively comfortable life. In the past, the area around Phayao Lake was the area where water from the mountains flowed into streams, rivers, and became small swamps during the dry season every year. The lessening of water makes the farmers able to use the area for farming, raise animals, and use as the route from the city to

270-408: Is the rigid, outermost rocky shell of a terrestrial planet or natural satellite . On Earth , it is composed of the crust and the lithospheric mantle , the topmost portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more. The crust and upper mantle are distinguished on the basis of chemistry and mineralogy . Earth's lithosphere, which constitutes

300-426: Is velocity of the lithospheric plate. Oceanic lithosphere is less dense than asthenosphere for a few tens of millions of years but after this becomes increasingly denser than asthenosphere. While chemically differentiated oceanic crust is lighter than asthenosphere, thermal contraction of the mantle lithosphere makes it more dense than the asthenosphere. The gravitational instability of mature oceanic lithosphere has

330-502: Is very different from that recognized in Nelson (1994)". Claroteidae and Austroglanididae contain species that were previously bagrids. Auchenoglanididae is considered by some sources to be a subfamily of Claroteidae and by others to be its own family, sister to Heptapteridae . In addition some authorities place the genus Horabagrus in the family Horabagridae together with two genera which are currently normally regarded as being in

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360-602: Is very fertile. Communities around the river has existed since ancient time. The temperature of the area is ranges from 19.5 °C to 27.5 °C. The average rainfall per year is around 1,064 mm. There are 36 recorded different varieties of aquatic plants in Phayao Lake. The major underwater plants are Ceratophyllum demersum and Najas graminea while other plants mainly include Slavonia cucullata , Nelumbo nucifera , Eichhornia crassipes , and Scrirpus grossus . The estimated mass of fishing crop per hectare

390-403: The chestnuts . The water hyacinth occupies about one-third of the area of Phayao Lake. The grasses are of different types: Johnson grass (หญ้าปล้อง) and Leucas aspera (หญ้าเค้านก) are seen in the dry season, when water decreases. Lithosphere A lithosphere (from Ancient Greek λίθος ( líthos )  'rocky' and σφαίρα ( sphaíra )  'sphere')

420-426: The ocean basins . Continental lithosphere is associated with continental crust (having a mean density of about 2.7 grams per cubic centimetre or 0.098 pounds per cubic inch) and underlies the continents and continental shelves. Oceanic lithosphere consists mainly of mafic crust and ultramafic mantle ( peridotite ) and is denser than continental lithosphere. Young oceanic lithosphere, found at mid-ocean ridges ,

450-400: The west . The other one called “Kwan Luang,” located in the east , near the right part of Ing River. In the dry season , the local people went there for fishing , it was overcrowded and no one was able to control the situation. Another problem is that the water was getting low in every year. The Department of Fisheries decided to build the floodgate in 1939 and finished in 1941. However, it

480-438: The Earth." They have been broadly accepted by geologists and geophysicists. These concepts of a strong lithosphere resting on a weak asthenosphere are essential to the theory of plate tectonics . The lithosphere can be divided into oceanic and continental lithosphere. Oceanic lithosphere is associated with oceanic crust (having a mean density of about 2.9 grams per cubic centimetre or 0.10 pounds per cubic inch) and exists in

510-419: The asthenosphere deforms viscously and accommodates strain through plastic deformation . The thickness of the lithosphere is thus considered to be the depth to the isotherm associated with the transition between brittle and viscous behavior. The temperature at which olivine becomes ductile (~1,000 °C or 1,830 °F) is often used to set this isotherm because olivine is generally the weakest mineral in

540-523: The concept and introduced the term "lithosphere". The concept was based on the presence of significant gravity anomalies over continental crust, from which he inferred that there must exist a strong, solid upper layer (which he called the lithosphere) above a weaker layer which could flow (which he called the asthenosphere ). These ideas were expanded by the Canadian geologist Reginald Aldworth Daly in 1940 with his seminal work "Strength and Structure of

570-408: The continental lithosphere are billions of years old. Geophysical studies in the early 21st century posit that large pieces of the lithosphere have been subducted into the mantle as deep as 2,900 kilometres (1,800 mi) to near the core-mantle boundary, while others "float" in the upper mantle. Yet others stick down into the mantle as far as 400 kilometres (250 mi) but remain "attached" to

600-403: The continental plate above, similar to the extent of the old concept of "tectosphere" revisited by Jordan in 1988. Subducting lithosphere remains rigid (as demonstrated by deep earthquakes along Wadati–Benioff zone ) to a depth of about 600 kilometres (370 mi). Continental lithosphere has a range in thickness from about 40 kilometres (25 mi) to perhaps 280 kilometres (170 mi);

630-437: The effect that at subduction zones, oceanic lithosphere invariably sinks underneath the overriding lithosphere, which can be oceanic or continental. New oceanic lithosphere is constantly being produced at mid-ocean ridges and is recycled back to the mantle at subduction zones. As a result, oceanic lithosphere is much younger than continental lithosphere: the oldest oceanic lithosphere is about 170 million years old, while parts of

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660-559: The hard and rigid outer vertical layer of the Earth, includes the crust and the lithospheric mantle (or mantle lithosphere), the uppermost part of the mantle that is not convecting. The lithosphere is underlain by the asthenosphere which is the weaker, hotter, and deeper part of the upper mantle that is able to convect. The lithosphere–asthenosphere boundary is defined by a difference in response to stress. The lithosphere remains rigid for very long periods of geologic time in which it deforms elastically and through brittle failure, while

690-402: The lake. Dikes were built to trap sediment, unwanted weeds were removed and used for animal feed, and the lake was stocked with native fish. As a result, the water storage capacity of the lake increased by 370,000 cubic metres. As a result, water from the lake was able to provide for 16,500 nearby families and 43,785  rai (7,005.6 ha; 17,311 acres) of farmland. The land around the lake

720-705: The mantle flow that accompanies plate tectonics. The upper part of the lithosphere is a large habitat for microorganisms , with some found more than 4.8 km (3 mi) below Earth's surface. Bagridae Bagrichthys Bagroides Bagrus Batasio Chandramara Coreobagrus Hemibagrus Hemileiocassis Horabagrus Hyalobagrus Leiocassis Mystus Nanobagrus Olyra Pelteobagrus Pseudobagrus Pseudomystus Rama Rita Sperata Sundolyra Tachysurus Eomacrones   † Gobibagrus   † Nigerium   † Nkondobagrus   † The Bagridae are

750-476: The northern and southern ends of the area during summer is dry, so it is possible to walk through the area. Before 1941, Phayao Lake was a vast area of lowland . It was humid in the rainy season (around July to November). The Ing River flowed through the area, creating many large ponds called “nong” and smaller ones called “buak”. The floodwaters made waterways connected with each other creating two lakes, one called “Kwan Noi” which means small lake, located in

780-419: The oceanic mantle lithosphere, κ {\displaystyle \kappa } is the thermal diffusivity (approximately 1.0 × 10  m /s or 6.5 × 10  sq ft/min) for silicate rocks, and t {\displaystyle t} is the age of the given part of the lithosphere. The age is often equal to L/V, where L is the distance from the spreading centre of mid-oceanic ridge , and V

810-664: The surrounding villages of Phayao. The area of Phayao Lake was the urban area which had lot of temples before. Later, when the Department of Fisheries created a water gate in Phayao to keep water, the temple was submerged in the area. By 2009, the lake had become a shallow, degraded water source. It was clogged with weeds. Sediment had decreased its depth. Fish stocks had dwindled. The Hydro and Agro Informatics Institute (HAII) and other agencies, inspired by King Bhumibol Adulyadej 's emphasis on water management, stepped in to rejuvenate

840-605: The upper approximately 30 to 50 kilometres (19 to 31 mi) of typical continental lithosphere is crust. The crust is distinguished from the upper mantle by the change in chemical composition that takes place at the Moho discontinuity . The oldest parts of continental lithosphere underlie cratons , and the mantle lithosphere there is thicker and less dense than typical; the relatively low density of such mantle "roots of cratons" helps to stabilize these regions. Because of its relatively low density, continental lithosphere that arrives at

870-534: The upper mantle. The lithosphere is subdivided horizontally into tectonic plates , which often include terranes accreted from other plates. The concept of the lithosphere as Earth's strong outer layer was described by the English mathematician A. E. H. Love in his 1911 monograph "Some problems of Geodynamics" and further developed by the American geologist Joseph Barrell , who wrote a series of papers about

900-417: Was flooded over the field, house, temple, and archaeological site, creating much damage. The natural swamps changed into large reservoirs. The Department of Fisheries established a fisheries research station at Phayao Lake to breed fish for the lake as part of the campaign to increase the availability of cheap protein diet for public consumption. Aquatic flora from Phayao Lake are used as animal feed. Phayao Lake

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