hydrothermal hole is a gap in the surface of the planet from which geothermal hot water problems. Hydrothermal ventilation is commonly found near active volcanic sites, areas where tectonic plates move separately in dispersal centers, ocean basins, and hotspots. Hydrothermal ventilation exists because the earth is geologically active and has large amounts of water on its surface and in its crust. Common land types include hot springs, fumaroles and geysers. Under the sea, hydrothermal holes can form a feature called black smokers . Relative to the majority of the deep ocean, the area around the underwater hydrothermal vents is biologically more productive, often hosting complex communities triggered by chemicals dissolved in ventilation fluid. Bacteria and chemosynthetic archaea form the basis of the food chain, supporting a variety of organisms, including giant tube worms, shellfish, limpets and shrimp. Active hydrothermal ventilation is believed to exist in the Jupiter Europa moon, and Saturn's moon Enceladus, and speculates that ancient hydrothermal holes once existed on Mars.
Video Hydrothermal vent
Physical properties
Hydrothermal vents in the deep ocean typically form along the oceanic mountains, such as the East Pacific Rise and Mid-Atlantic Ridge. This is the location where two tectonic plates deviate and a new crust is formed.
The expelled water from hydrothermal vents of the seabed consists mainly of sea water drawn into the hydrothermal system close to the volcanic building through fractures and porous sediments or volcanic strata, plus some magmatic water released by upwelling magma. In terrestrial hydrothermal systems, most of the water circulating in the fumarole and fountain systems is meteoric water plus groundwater that has seeped into the thermal system from the surface, but also generally contains parts of metamorphic water, magmatic water, and sediments. Formal salt water released by magma. The proportion of each varies from location to location.
In contrast to about 2 ° C, ° ° C (36 ° F) of ambient water temperature at this depth, water emerges from this ventilation at temperatures from 60 ° C to 1404 ° F to as high as 464 ° C (867 ° F). Due to the high hydrostatic pressure at this depth, water may be present in its liquid form or as a supercritical liquid at that temperature. The water (pure) critical point is 375 ° C (707 ° F) at atmospheric pressure of 218 °. However, inserting salinity into the liquid increases the critical point to higher temperatures and pressures. The critical point of sea water (3.2% NaCl) is 407 Â ° C (765 Â ° F) and 298.5 rods, corresponding to a depth of ~ 2,960 m (9,710 ft) below sea level. Thus, if hydrothermal fluid with salinity 3.2% NaCl vents above 407 ° C (765 ° F) and 298.5 bars, it is supercritical. Furthermore, salinity of ventilation fluid has been shown to vary greatly due to phase separation in the crust. The critical point for lower salinity is lower temperature and pressure conditions than for seawater, but higher than that for pure water. For example, a ventilation fluid with NaCl salinity 2.24% NaCl has a critical point at 400 ° C (752 ° F) and 280.5 bars. Thus, water emerging from the hottest part of some hydrothermal vents can be a supercritical fluid, which has a physical property between gas and liquid.
Examples of supercritical ventilation are found on some sites. Sister Peak (Scheme hydrothermal Coveless, 4A, Â ° 48? S 12Ã, Â ° 22? W , a depth of 2,996 m or 9.829Ã, ft) releases a separate liquid phase separated by low salinity levels. Ongoing ventilation was not found supercritical but the short injection of 464 Â ° C (867 Â ° F) was far above supercritical conditions. A nearby site, Turtle Pits, was found to vent low salinity fluid at 407 ° C (765 ° F), which is above the critical point of the liquid in the salinity. A site vents in the Cayman Trough named Beebe, a hydrothermal site deepest in the world with a height of ~ 5,000 m (16,000 ft) below sea level, has shown the ventilation supercritical at 401 ° C (754 ° F) and 2.3% NaCl.
Although supercritical conditions have been observed in some sites, it is unknown what significance, if any, of supercritical ventilation in terms of hydrothermal circulation, the formation of mineral deposits, geochemical fluxes or biological activity.
The initial stages of the venting chimney begin with the deposition of anhydrine minerals. Copper, iron, and zinc sulphides then settle in the chimney gap, making it less porous all the time. Vent growth on the order of 30 cm (1 foot) per day has been recorded. Offshore exploration in April 2007 off the coast of Fiji found that the vents became a significant source of dissolved iron.
Maps Hydrothermal vent
Black smokers and white smokers
Some hydrothermal holes form a coarse cylinder chimney structure. It is formed from dissolved minerals in liquids. When super-hot water touches almost frozen sea water, the mineral stays out to form particles which increase the height of the stack. Some of these chimney structures can reach a height of 60 m. An example of the towering hole is "Godzilla", a structure on the Pacific Ocean bottom of Oregon near which rises to 40 m before falling in 1996.
A black smoker or in in the ocean is a type of hydrothermal hole found on the seabed, usually in the bath zone (with the largest frequency at depths from 2500 m to 3000 m ), but also at lower and deeper depths in the abyssal zone. They look like black, chimney-like structures that emit black material butt. Black smokers typically emit particles with high levels of sulfur-bearing minerals, or sulphides. Black smokers are formed in fields with hundreds of meters wide when superheated water from below the Earth's crust comes through the ocean floor (water may reach temperatures above 400 ° C). This water is rich in dissolved minerals from the crust, especially sulfides. When it comes in contact with cold sea water, many minerals precipitate, forming structures, like black chimneys around each vent. The stored metal sulfur can become a massive sulfide ore deposit in time. Some black smokers in the Azores section of Mid Atlantic Ridge are very rich in metal content, like Rainbow with 24,000 concentrations? M iron.
Black smokers were first discovered in 1979 at the East Pacific Rise by scientists from Scripps Institution of Oceanography. They were observed using a deep vehicle ALRIN from the Woods Hole Oceanographic Institution. Now, black smokers are known to exist in the Atlantic and Pacific Oceans, at an average depth of 2,100 meters. The northernmost black smoker is a group of five named Loki Castle, discovered in 2008 by scientists from the University of Bergen at 73 Â ° N, in the Central Ridge of the Atlantic between Greenland and Norway. Black smokers are interesting because they are in a more stable region of the Earth's crust, where tectonic strength is less and consequently the field of hydrothermal ventilation is less common. The world's most famous black smoker is located in Cayman Trough, 5,000 m (3.1 mi) below sea level.
White smokers vents emit brighter lighter minerals, such as those containing barium, calcium, and silicon. These ventricles also tend to have lower temperatures probably because they are generally far from their heat source.
Black and white smokers can coexist in the same hydrothermal field, but they generally represent the proximal and distal ventilation to the main upflow zones, respectively. However, white smokers correspond largely to the waning phase of the hydrothermal field, since magmatic heat sources are becoming increasingly distant from the source (because magical crystallization) and hydrothermal fluids are dominated by sea water, not magmatic water. Mineralized water of this type of ventilation is rich in calcium and they form the dominant rich sulfate (ie, barite and anhydrite) and carbonate deposits.
Community biology
Life is traditionally seen as driven by energy from the sun, but deep-sea organisms do not have access to sunlight, so they must rely on the nutrients found in the dusty chemical deposits and the hydrothermal fluids in which they live. Previously, benthic oceans assumed that ventilation organisms depended on sea snow, such as deep-sea organisms. This will make them dependent on plant life and thus the sun. Some hydrothermal ventilation organisms do consume this "rain", but only with such systems, life forms will be very rare. Compared to the surrounding seafloor, however, the hydrothermal ventilation zones have a density of organisms 10,000 to 100,000 times greater.
The hydrothermal graft community is able to sustain an enormous amount of life because the ventilation organism relies on the bacterial bacteria for food. Water from hydrothermal holes is rich in dissolved minerals and supports large populations of chemoautotrophic bacteria. These bacteria use sulfur compounds, especially hydrogen sulphide, a highly toxic chemical for the most well known organisms, to produce organic matter through the chemosynthesis process.
The ecosystems that depend on the continuity of the hydrothermal venting field as the main source of energy, which is different from most of the Earth's surface life, based on solar energy. However, while it is often said that this community exists independently of the sun, some organisms actually depend on oxygen produced by photosynthetic organisms, while others are anaerobic.
Bacteriosynthetic bacteria grow into thick mats that attract other organisms, such as amphipods and copepods, which directly graze on bacteria. Larger organisms, such as snails, shrimp, crabs, tube worms, fish (especially eelpout, throat eel, ophidiiforms and Symphurus thermophilus), and octopus (especially Vulcanoctopus hydrothermalis ) , forming predatory food chains and prey relationships over top consumers. The main families of organisms found around sea vents are annelids, pogonophoras, gastropods, and crustaceans, with large bivalves, vestimiform worms, and "eyeless" shrimps that make up most non-microbial organisms.
Siboglinid tube worms, which can grow up to more than 2 m (6.6 ft) in the largest species, often form an important part of the community around the hydrothermal vents. They have no mouth or digestive tract, and like parasitic worms, absorb the nutrients produced by bacteria in their tissues. About 285 billion bacteria are found per ounce of tubeworm tissue. Worm tubes have red feathers containing hemoglobin. Hemoglobin combines with hydrogen sulfide and transfers it to bacteria that live in the worm. In return, the bacteria nourish the worms with carbon compounds. The two species that inhabit the hydrothermal pits are Tevnia jerichonana , and Riftia pachyptila . One community found, dubbed "Eel City", consists mostly of eels Dysommina rugosa. Although eels are not uncommon, invertebrates usually dominate the hydrothermal vents. Eel City is located near the faucet of Nafanua volcano, American Samoa.
By 1993, more than 100 species of gastropods were known to occur in hydrothermal vents. More than 300 new species have been found in hydrothermal vents, many of them "sister species" for others found in geographically separated ventilation areas. It has been proposed that before the North American plate overrides the ridge at sea, there is a single ventricular area found in the eastern Pacific. The next barrier to travel begins the divergence of species evolution in different locations. Examples of convergent evolutions seen between different hydrothermal holes are seen as major support for the theory of natural selection and overall evolution.
Although life is very rare in this depth, black smokers are at the center of the entire ecosystem. Sunlight does not exist, so many organisms - such as archaea and extremophiles - alter the heat, methane, and sulfur compounds provided by black smokers into energy through a process called chemosynthesis. More complex life forms, such as shells and tube worms, feed on these organisms. The organism at the base of the food chain also stores minerals to the base of the black smoker, thus completing the life cycle.
Phototrophic bacteria species have been found living near black smokers off the coast of Mexico at a depth of 2,500 m (8,200 ft). No sunlight penetrates deep into the water. In contrast, bacteria, part of the Chlorobiaceae family, use the faint light of black smokers for photosynthesis. This is the first organism found in nature to exclusively use light other than sunlight for photosynthesis.
New and unusual species continue to be found in the environment of black smokers. The Pompeii worm Alvinella pompejana , which can withstand temperatures of up to 80 Ã, Â ° C (176Ã, Â ° F), was discovered in 1980, and foot-scaled gastropods Chrysomallon squamiferum in 2001 during an expedition to Kairei's hydrothermal hole area in the Indian Ocean. The latter uses iron sulphide (pyrite and greigite) for the structure of the sclerites dermanya (hardened part of the body), not calcium carbonate. The extreme pressure of 2500 m of water (about 25 megapascals or 250 atmospheres) is thought to play a role in stabilizing iron sulphide for biological purposes. This armor coating may serve as a defense against the venomous (tooth) radon of a predatory snail in the community.
In March 2017, researchers reported evidence of possibly the oldest form of life on Earth. The fossil microorganisms suspected to be found in hydrothermal ventilation precipitates at the Nuvvuagittuq Belt in Quebec, Canada, may have lived since 4.280 billion years ago, shortly after the oceans formed 4.4 billion years ago, and not long after Earth formation. 4.54 billion years ago.
Biological Theory
Although the discovery of the hydrothermal pit is a relatively recent event in the history of science, the significance of this invention has spawned, and supports, new biological and bio-atmospheric theories.
The Deep Hot Biosphere
In early 1992 his paper The Deep Hot Biosphere Thomas Gold refers to marine ventilation to support his theory that the lower levels of the earth are rich in living biological matter. who find his way to the surface. He further expanded his ideas in the book The Deep Hot Biosphere .
An article on Abiogenic hydrocarbon production in the February 2008 issue of the journal Science uses data from an experiment in the Hydrothermal Field of the Lost City to report how the abiotic synthesis of low molecular mass hydrocarbons from carbon dioxide derived from the mantle can occur in the presence of ultramafic rock , water, and moderate amounts of heat.
Hydrothermal origin
The chemical and thermal dynamics in hydrothermal vents make such environments very thermodynamically suitable for the process of chemical evolution to take place. Therefore, thermal energy flux is a permanent agent and contribute to planetary evolution, including prebiotic chemistry.
GÃÆ'¼nter WÃÆ'¤chtershÃÆ'¤user proposed the theory of iron sulfur world and suggested that life may come from hydrothermal vents. WÃÆ'¤chtershÃÆ'¤user proposes that the early form of metabolism precedes genetics. By metabolism it means the cycle of chemical reactions that release energy in a form that can be utilized by other processes.
It has been proposed that the synthesis of amino acids can occur deep within the Earth's crust and that these amino acids are then lifted together with hydrothermal fluids into colder water, where lower temperatures and the presence of clay minerals will foster the formation of peptides and proto cells This is a hypothesis which is interesting because of the abundance of CH 4 (methane) and NH 3 (ammonia) is present in the hydrothermal ventilation area, a condition not provided by a primitive Earth atmosphere. The main limitation to this hypothesis is the lack of stability of organic molecules at high temperatures, but some have suggested that life will originate outside the highest temperature zone. There are many species of extremophiles and other organisms that currently live directly around deep sea holes, suggesting that this is indeed a possible scenario.
Experimental research and computational modeling show that the surface of mineral particles in the hydrothermal vents have catalytic properties similar to those of enzymes and are able to create simple organic molecules, such as methanol (CH 3 OH) and formic acid (HCO). 2 H), out of the dissolved CO 2 in the water.
It is thought that alkaline hydrothermal vents (white smokers) may be more suited to emerging lives than black smokers because of their pH conditions.
Invention and exploration
In 1949, a deep water survey reported very hot salt water in the middle of the Red Sea. Then work in the 1960s confirmed the presence of heat, 60 Â ° C (140 Â ° F), salt water and sludge associated with metal. The hot solution comes from an active subseafloor gap. The highly saline water character is not friendly to living organisms. The associated brines and associated sludges are currently being investigated as a source of precious metals and mined metals.
In June 1976, Scripps Institution of Oceanography scientists obtained the first evidence for undersea hydrothermal vents along GalÃÆ'¡pagos Rift, a boost from the East Pacific Rise, on the Pleiades II expedition , using the Deep- Seafloor imaging system Tow. In 1977, the first scientific paper on hydrothermal ventilation was published by Scripps Institution of Oceanography scientists; research scientist Peter Lonsdale published photographs taken from in-crane cameras, and PhD student Kathleen Crane published maps and temperature anomalous data. Transponders deployed on the site, dubbed "Clam-bake", to allow the expedition to return the following year for live observation with DSV ALVIN.
The chemosynthetic ecosystem surrounding the hydrothermal vent GalÃÆ'¡pagos The hydrothermal rift was first observed directly in 1977, when a group of marine geologists funded by the National Science Foundation returned to the Clambake site. The principal investigator for submersible studies is Jack Corliss of Oregon State University. Corliss and Tjeerd van Andel from Stanford University watched and sampled the vent and ecosystem on February 17, 1977, while diving at DSV ALVIN, a research submarine operated by Woods Hole Oceanographic Institution (WHOI). Other scientists included Richard (Dick) Von Herzen and Robert Ballard of WHOI, Jack Dymond and Louis Gordon of Oregon State University, John Edmond and Tanya Atwater from Massachusetts Institute of Technology, Dave Williams of the US Geological Survey, and Kathleen Crane of Scripps Institution of Oceanography. The team publishes their observations on ventilation, organisms and the composition of ventilation fluids in the journal Science. In 1979, a team of biologists led by J. Frederick Grassle, at WHOI, returned to the same location to investigate the biological community discovered two years earlier.
High-temperature hydrothermal vents, "black smokers", were discovered in the spring of 1979 by a team from Scripps Institution of Oceanography using submersible ALVIN. The RISE expedition is exploring the East Pacific Rise at 21Ã, Â ° N with the aim of testing seabed geophysical mapping with ALVIN and finding other hydrothermal fields outside the GalÃÆ'¡pagos Rift vent. The expedition was led by Fred Spiess and Ken Macdonald and included participants from the US, Mexico, and France. The dive area was chosen based on the discovery of base mounds of sulphide minerals at sea by the French CYAMEX expedition in 1978. Prior to diving operations, members of the Robert Ballard expedition located near the bottom of the water temperature anomaly using a highly-drawn instrument package. The first dive is targeted at one of these anomalies. On Easter Sunday April 15, 1979 when diving ALVIN up to 2600 meters, Roger Larson and Bruce Luyendyk found a hydrothermal ventilation field with a biological community similar to Galápagos ventilation. On the next dive, William Normark and Thierry Juteau find high-temperature vents that emit jet black mineral particles from the chimney; black smoker. After this Macdonald and Jim Aiken installed the temperature probe to ALVIN to measure the water temperature in the black smoker vents. It observed the highest temperatures then recorded on deep ocean hydrothermal vents (380 Â ± 30 ° C). Analysis of black smokers and chimneys feeding them revealed that iron sulphide precipitates are common minerals in "smoke" and chimney walls.
In 2005, Neptune Resources NL, a mineral exploration company, filed an application and granted an exploration rights of 35,000 km2 over Kermadec Arc in New Zealand's Exclusive Economic Zone to explore massive ocean sulphide deposits, a potential new source of copper-lead-zinc sulphide formed from modern hydrothermal ventilation field. The discovery of a vent in the Pacific Ocean off Costa Rica, named Medusa hydratotermal ventilation field (after Medusa fibers from Greek mythology), was announced in April 2007. Ashadze hydrothermal field (13 Â ° N at Mid-Atlantic Ridge, elevation -4200 m) was the highest known deep-temperature hydrothermal field until 2010, when hydrothermal lumps originating from the Beebe site ( 18Ã, Â ° 33 ° N 81Ã, Â ° 43? W , elevation -5000 m) was detected by a group of scientists from the NASA Jet Propulsion Laboratory and Woods Hole Oceanographic Institution. The site is located at 110 km long, ultraslow spread Mid-Cayman Rise in Cayman Trough. In early 2013, the deepest hydrothermal hole is known to be found in the Caribbean at depths of nearly 5,000 meters (16,000 feet).
Marine experts are studying volcanoes and hydrothermal holes in Juan de Fuca in the middle of the ocean where tectonic plates move away from each other.
Hydrothermal ventilation and other geothermal manifestations are currently being explored in the BahÃÆ'a de ConcepciÃÆ'³n, Baja California Sur, Mexico.
Distribution
Hydrothermal vents tend to be distributed along the boundaries of the Earth's plates, although they can also be found in intra-plate locations such as hotspot volcanoes. In 2009 there were about 500 known active submarine hydrothermal hole fields, with about half visually observed on the seafloor and the other half suspected from indicators of water column and/or seafloor deposits. The InterRidge program office maintains a global database for the site of a well-known underwater hydrothermal field.
Rogers et al. (2012) recognizes at least 11 biogeographic provinces of hydrothermal ventilation systems:
- Mid-Atlantic Ridge province,
- East Scotia Ridge Province,
- North East Pacific Rise province,
- East Pacific central province Rising,
- South East Pacific Rise province,
- south of the Easter Micro,
- Indian Ocean Province,
- four provinces in the western Pacific.
Exploit
Hydrothermal ventilation, in some cases, has led to the formation of mineral resources exploited by depositing deposits of massive sulphide seas. The Isa mountains, located in Queensland, Australia, is an excellent example. Many hydrothermal holes are rich in cobalt, gold, copper, and rare earth metals essential for electronic components. Hydrothermal vents on the Arkean seafloor are thought to have formed an Algoma-type iron formation that has been a source of iron ore.
Recently, mineral exploration companies, driven by high price activities in the base metals sector during the mid-2000s, have turned their attention to mineral resource extraction from hydrothermal fields on the seafloor. Significant cost reductions are, in theory, possible.
Two companies are currently involved in the final phase of mine starting massive sulphide on the seafloor. The Nautilus Minerals are in the advanced stages of extraction from the Solwarra deposit, in the Bismarck Islands, and Neptune Minerals in the early stages with the Rumble II West deposit, located in the Kermadec Arc, near the Kermadec Islands. Both companies propose using modified technology. Nautilus Minerals, in partnership with Placer Dome (now part of Barrick Gold), succeeded in 2006 in restoring more than 10 metric tons of SMS mined to the surface using a modified drum modifier mounted on the ROV, the first in the world. Neptune Minerals in 2007 succeeded in recovering SMS sediment samples using a modified industrial oil suction pump installed on the ROV, also the first in the world.
Seabed mining potentials have environmental impacts including dust clumps from mining machinery affecting filtering organisms, collapse vents or reopening, release of methane clathrates, or even sub-ocean soil slides. A large amount of work is currently being engaged by the two companies mentioned above to ensure that the potential environmental impacts of seabed mining are well understood and control measures implemented, before exploitation begins.
Efforts have been made in the past to exploit minerals from the ocean floor. The 1960s and 1970s saw much activity (and expenditure) in the recovery of manganese nodules from abyssal plains, with varying degrees of success. This does indicate that mineral recovery from the seabed is possible, and has been possible for some time. Interestingly, the mining of manganese nodules serves as a cover story for a complicated attempt in 1974 by the CIA to raise a sinking Soviet submarine K-129 , using Glomar Explorer, a ship destination built for the task by Howard Hughes. This operation is known as the Azorian Project, and the cover story on seabed mining of the manganese nodule may have served as an incentive to encourage other companies to make the effort.
Preservation
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