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Endeavour Hydrothermal Vents

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Endeavour Hydrothermal Vents Marine Protected Area
Part of a 360 °C black smoker chimney of the Endeavour Hydrothermal Vents
Map showing the location of Endeavour Hydrothermal Vents Marine Protected Area
Map showing the location of Endeavour Hydrothermal Vents Marine Protected Area
Location off the coast of Vancouver Island in British Columbia, Canada
LocationJuan de Fuca Ridge
British Columbia, Canada
Coordinates47°57′N 129°06′W / 47.950°N 129.100°W / 47.950; -129.100 (Endeavour Hydrothermal Vents)
Area97 km2 (37 sq mi)[1]
DesignationMarine Protected Area
DesignatedMarch 2003
Governing bodyFisheries and Oceans Canada

The Endeavour Hydrothermal Vents (also known as the Main Endeavour Field, MEF, or EHV) are a group of hydrothermal vents in the north-eastern Pacific Ocean, located 260 kilometres (160 mi) southwest of Vancouver Island, British Columbia, Canada.[2] The vent field lies 2,250 metres (7,380 ft) below sea level on the northern Endeavour segment of the Juan de Fuca Ridge. In 1982, dredged sulfide samples were recovered from the area covered in small tube worms and prompted a return to the vent field in August 1984, where the active vent field was confirmed by HOV Alvin on leg 10 of cruise AII-112.[3][4][5]

The temperatures within the Endeavour Hydrothermal Vent fields differs at the various depths despite some vents being just metres apart. This also has an effect on the different microorganisms and invertebrates that live within the region. In order to best grasp the scale of the EHV region, autonomous vehicles have been deployed to survey the areas and cable systems have been put in place so that that better management practices can be taken. The protected area for the Endeavour Hydrothermal Vents is located on the ridge of the Juan de Fuca plate, and the established zone is 100 km2 (39 sq mi).[6]

The vent field falls under Canadian jurisdiction and designated as a Canadian Marine Protected Area.

Geology and geomorphology

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Computer generated image of the Endeavour Hydrothermal Vent (EHV) field chimneys

The Endeavour section of the Juan de Fuca Ridge is approximately 90 km long and spreads at 6 cm per year.[7] Along the ridge, there are six major vent fields (including Stockwork) and over 800 individual chimneys have been recorded over a 15 kilometres (9.3 mi) section of the ridge.[8] Other vent fields of this section include High Rise, Mothra, Salty Dawg, Sasquatch, and Stockwork. All sites are basalt-hosted.

The MEF is located on the west side of the spreading axis at a depth of approximately 2,200 metres (7,200 ft).[9] The mineralogy of the vent field is dominated by metal sulfides, particularly those of iron and zinc. Major sulfide phases consist of pyrite, chalcopyrite, wurtzite, and marcasite.[3] The MEF has a significant amount of inactive chimneys and is estimated to have been active for at least 2,300 years.[9] Within the field, there are 16 named venting sites (as assembled by InterRidge).[4] These sites are: Bastille, Crypto, Dante, Dudley, Easter Island, Grotto, Hulk, Lobo, MilliQ, Peanut, Puffer, Salut, Smoke & Mirrors, Sully, TP, and Quebec.

The Endeavour segment is tectonically active and there have been many reported tectonic events since the discovery of the MEF.[10] Tectonic events like diking, such as those detected by SOSUS in 1999, caused vent geochemistry to change drastically throughout the field. Another diking event was detected in 2005. Following these events, the hydrothermal activity of the MEF has been waning and some venting sites like MilliQ have been confirmed to be extinct.[7]

Vent structure

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Hydrothermal vents can sometimes be seen as roughly cylindrical chimney structures. Minerals that are dissolved in the vent fluid give rise to the vents overall structure. This is because minerals precipitate out to produce particles that increase the height of the stacks when the superheated water comes into contact with the sea water that is almost frozen. This can result in the chimney's structure growing up to 60 metres.[11] Only the axial graben and the graben's near rims above the seismically observed magma lens exhibit hydrothermal activity. Main Endeavour has shown very little volcanic activity over the past 4,300 years, and as such, dormant chimneys are not buried as they are on other peaks.[12]

The hydrothermal vents in the area also consist of black and white smoker chimneys that are 20 metres (66 ft) or taller. Black smokers emit black fumes due to being formed from deposits of iron sulfide, whereas white smokers contain barium, calcium, and silicon, and as such emits a lighter-hue of smoke.[13]

Deep sea vent chemistry diagram

Heating and chemistry

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Heat of the Endeavour Hydrothermal Vents is supplied by the conductive cooling of the Earth's crust along the axis and from magmatic sources beneath the field. Seawater seeps diffusively or through cracks into the Earth's crust, warms at depth, and then rises back up after it is heated at venting orifices.[8] This heated water supplies energy and nutrients for chemoautotrophic organisms to thrive in this environment.[14]

Chemical ecology

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A large, intricate ecology is supported on and below the deep ocean floor by hydrothermal vents connected to the system of global oceanic ridges. Fluids from deep ocean vents have a diverse spectrum of chemical compositions and are frequently enriched in metal sulfides, such as those from iron, copper, calcium, silicon, and zinc as well as metalloids.[15] The cooling and mixing of hot hydrothermal fluids with cold seawater results in the formation of hydrothermal vent deposits on the seafloor. Among the major sulphide and sulphate minerals preserved at vent sites, barite (BaSO 4) is unique in that precipitation requires the direct mixing of Ba-rich hydrothermal fluid with sulfate-rich seawater. Barite crystals retain geochemical fingerprints associated with formation conditions due to their extremely low solubility.[16]

Thermal biology

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With reported vent temperatures of 402 °C (756 °F), phase separation has been inferred to occur within fluids beneath the field.[4][10] Differing ratios of brine and vapour phases have been used to characterize geochemistry at sites such as Bastille and Dante.[10] High temperatures also allow metals to stay in solution, allowing for distinctive black-smoker chimneys. Through a combination of targeted, high-temperature (350 °C) venting and diffuse, low-temperature (10-25 °C) venting, the Main Endeavour field alone produces a total heat flux of 650±100 megawatts (MW). According to their thermal, particle, and chemical anomalies, vent plumes rise 50 to 350 metres above the seafloor to a level of neutral buoyancy. While the plumes rising above the ridge crests are free to drift with the ambient flow, the deeper portions of the plumes may remain stuck inside the valley.[17]

The environment of the Endeavour Hydrothermal Vent field experiences extreme temperature ranges of 300 °C all the way down to 2 °C from even just a few metres away. Stressors like elevated acidity, carbon dioxide (CO2), sulfide, anoxia, and metal ions are just a few examples of the extreme conditions in fluid vents. The hydrothermal vents wouldn't normally be thought of as able to sustain a reliable habitat due to the turbulent nature of the vent fluid. However, researchers have found that the vents are stable for most of the year except for a 40 °C temperature spikes in the month of April. Although temperatures this high can be lethal to organisms existing there, habitats there can be stable even at well below preferred temperatures. Researchers have theorized that vent animals have adapted to the rapid change in temperatures and thus are able to live within or near these vents.[18]

Spider crabs of the Juan de Fuca Ridge

Biodiversity

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Hydrothermal vents are located at mid-ocean ridges, where an abundance of life is present, providing high biodiversity and productivity. They provide habitats for many unique species of animals.[19] Researchers have identified 12 endemic species to the Endeavour Segment of the Juan de Fuca Ridge that do not exist anywhere else in the world including the sea spider (Sericosura venticola). This endemic species is currently classified as imperiled, and is at risk of facing extinction.[20] Many marine mammals, such as Dall's porpoise, sperm whales, Pacific white-sided dolphin, leatherback sea turtle, and northern elephant seal have also been spotted in the waters where vent fields are located.[21] The organisms at the hydrothermal vent systems range from microorganisms to invertebrates where each have an interchanging role with one another.[22][23][24] A sulfide-hosted microbe from this site can live in environments up to 121 °C, which is the record for the upper limit for life.[8][25]

Primary Endeavour Hydrothermal Vents and their distribution with one another

Microorganisms

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The microbiome population is made up mostly of proteobacteria and archaea. There is limited archaeal diversity, however, as only 12 phylotypes have been detected in the area. All others have been identified as being clones, with Desulfurococcales being the most common clone. Many of the microbes present in this environment have either a sulfur oxidizing or sulfur reducing metabolism, leading to the possibility of sulfur cycling in these areas.[22] Due to the large amount of microbial biomass, vent fields have become a hotspot for viruses.[26] Researchers found that high flow areas were dominated by sulfur and hydrogen oxidizing bacteria, while low flow areas were dominated by heterotrophic bacteria.[23] Epsilonproteobacteria are dominant bacteria at some sites of the MEF and genes have been identified that are associated with nitrogen fixation.[7]

Invertebrates

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The main invertebrate found in these areas is the tubeworm (Ridgeia piscesae), which has a “short fat” morphology when it is in high flow areas near the vents, and a 'long skinny' morphology when in low flow areas farther away from the vents.[23] The dominating invertebrate species that have been recorded are spider crabs (Macroregonia macrochira), sulphide worms (Paralvinella sulfincola), limpets (Lepetodrilus), polynoid scaleworms, and palm worms (Paralvinellae palmiformis) that belong to the Alvinellidae family.[18] Furthermore, symbiotic vent bacteria provide nutrients to the animals living there through the process of chemosynthesis since no sunlight reaches the depths of the Endeavour vent fields.[27][28]

Expeditions and marine protected area management

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The Endeavour hydrothermal vent fields are under the protection of the Marine protected areas (MPA), and was established in 2003 under the Oceans Act because of its diverse and unique biological environment.[6] Under these regulations, activities that pose any harm to vent systems is prohibited. The hydrothermal vent fields—Salty Dawg, High Rise, Main Endeavour, and Mothra—were divided up into four different subfields after being mapped in 1991. A fifth vent field, Sasquatch, was later discovered in 2000 and is situated just north of Salty Dawg.[29] Out of these vent fields, Mothra and Main Endeavour have had more researched performed on them compared to the other three. On the other hand, Salty Dawg and High Rise are labelled as having the highest precaution, limiting the number of observations and activities that can be done in the fields. The last remaining vent, Sasquatch, as well as other minor vents in the area, has yet to be included into any management plans.[6] Although the vents have been under the MPA's since 2003, a management plan for the fields was only enacted in 2010. The management plan focuses on four specific areas of study using "[a] precautionary approach, ecosystem-based approach, adaptive management, and collaboration".[29]

Autonomous underwater vehicle expeditions

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MBARI AUV D. Allan B deploying off Southern California

An unmanned remote-controlled vehicle, MBARI AUV D. Allan B.[30] and other autonomous underwater vehicles (AUV) revealed that there were 572 hydrothermal sulfide chimneys total, of which only 47 are known to be currently active within the 14-kilometre (8.7 mi) segment of the ridge. The primary data for this research was done by using MBARI AUV D. Allan B.[12]

First Nations involvement

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During the early 2000s, due to the geographical instabilities, many consultations and workshops were held to discuss and process the designation of the Endeavour Hydrothermal Vent system (EHV) as a MPA. During this time, the Central Region Board on Vancouver Island was included in the process. The Central Region Board was made up of all Nuu-chah-nulth First Nations Chiefs as well as representatives from local and regional governments. There were no objections from the Board. According to pre-designation presentations to the Central Region Board, there are no substantive First Nation interests in the EHV MPA. However, because the area falls within the statement of intent area of the Nuu-chahnulth Tribal Council (NTC) Treaty claim, the NTC may have an interest in managing the MPA in the future.[6]

Area protection

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Since the area is under the protection of the Marine Protected Areas act, any forms of deep-sea mining is prohibited within the area as this could harm the species that currently live there as well damage the hydrothermal vent systems. The area was under the MPA act before any mining could take place within the area. The government of Canada cannot prevent fishing vessels and normal routine traffic from going through the area, however, despite being a Marine Protected Area. This poses a problem because of the risk associated with pollution from the ships, oil spills, and noise that come with them.[31] Any violations of the MPA regulations within the area can face penalties under the Oceans Act, or Fisheries Act depending on the issue.[6]

Cabled observatory

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Ocean Networks Canada Cabled Observatory in the Hydrothermal Vent system

Since 1987, Canada has been utilizing their cabled observatory called North Pacific Time-Series Underwater Experiment (NEPTUNE). NEPTUNE was founded by the Ocean Networks Canada (ONC) in joint with the National Science Foundation's Ocean Observatories Initiative (OOI).[8][28] The US installed a sister cabled observatory at Axial Seamount called the Regional Cabled Array.

Established in 2011, real-time monitoring of the MEF became possible through a NEPTUNE node established at the site Grotto.[28] This enables scientific parameters, such as temperature, to be collected continuously. In 2017, the node was serviced to begin a major expansion to add additional cameras and in situ geochemical sensors.

Although there are five different vent fields that are observed and researched, the NEPTUNE cable observatory only extends from Mothra to Main Endeavour vent fields.[12] Furthermore, the real-time cable system for the Main Endeavour field was only established in 2010 by Ocean Networks Canada (ONC) as part of NEPTUNE, and real-time observing has been continuing since 2011. The installation of this cable was established so that better research opportunities and MPA management can be done.[32]

Scientific discoveries

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The Endeavour Hydrothermal vents are home to several important scientific discoveries which include:

  • 1982: discovery of the first vents in Juan de Fuca Ridge
  • 1984: exploration of the first extensive seafloor ore deposits
  • 1989: discovery of glowing vents, which are vents that emit thermal radiation due to high temperature fluids above 350 °C coming out of the vent.
  • 1990: discovery of highest neutral water temperatures known to Earth
  • 1991: first extensive usage of undersea robotic vehicles
  • 2000: Discovery of a fifth vent field, Sasquatch[29]
  • 2008-2011: Discovery of 572 chimneys in the area[12]
  • Discovery of the organism that holds the record for the upper temperature limit to life (121 °C)[8][25]
  • First evidence that hydrothermal plumes were zones of greatly enhanced zooplankton aggregation
  • First measurements of biomass fluxes relating to hydrothermal plumes

To this day, the Endeavour Hydrothermal Vents still continues to be a site where scientists such as biologists, geologists, physicists, microbiologists, and oceanographers gravitate toward to find new discoveries.[33]

See also

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References

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  1. ^ Government of Canada, Fisheries and Oceans Canada (2019-09-18). "Endeavour Hydrothermal Vents Marine Protected Area (MPA)". www.dfo-mpo.gc.ca. Retrieved 2020-09-10.
  2. ^ Leary, David Kenneth (2007). International Law and the Genetic Resources of the Deep Sea. Martinus Nijhoff Publishers. ISBN 978-9004155008.
  3. ^ a b Tivey, Margaret K.; Delaney, John R. (1986-04-01). "Growth of large sulfide structures on the endeavour segment of the Juan de Fuca ridge". Earth and Planetary Science Letters. 77 (3): 303–317. Bibcode:1986E&PSL..77..303T. doi:10.1016/0012-821X(86)90142-1. ISSN 0012-821X.
  4. ^ a b c "Main Endeavour Field | InterRidge Vents Database Ver. 3.4". vents-data.interridge.org. Retrieved 2022-10-16.
  5. ^ "HOV ALVIN DIVES DATA". www.kaggle.com. Retrieved 2022-10-16.
  6. ^ a b c d e Government of Canada, Public Services and Procurement Canada. "Information archivée dans le Web" (PDF). publications.gc.ca. Retrieved 2022-10-13.
  7. ^ a b c Kelley, Deborah; Carbotte, Suzanne; Caress, David; Clague, David; Delaney, John; Gill, James; Hadaway, Hunter; Holden, James; Hooft, Emilie; Kellogg, Jonathan; Lilley, Marvin; Stoermer, Mark; Toomey, Doug; Weekly, Robert; Wilcock, William (2012-03-01). "Endeavour Segment of the Juan de Fuca Ridge: One of the Most Remarkable Places on Earth". Oceanography. 25 (1): 44–61. doi:10.5670/oceanog.2012.03.
  8. ^ a b c d e "Endeavour Segment of the Juan de Fuca Ridge: One of the Most Remarkable Places on Earth | Oceanography". tos.org. Retrieved 2017-06-02.
  9. ^ a b Clague, David A.; Martin, Julie F.; Paduan, Jennifer B.; Butterfield, David A.; Jamieson, John W.; Le Saout, Morgane; Caress, David W.; Thomas, Hans; Holden, James F.; Kelley, Deborah S. (June 2020). "Hydrothermal Chimney Distribution on the Endeavour Segment, Juan de Fuca Ridge". Geochemistry, Geophysics, Geosystems. 21 (6). Bibcode:2020GGG....2108917C. doi:10.1029/2020GC008917. ISSN 1525-2027. S2CID 218825220.
  10. ^ a b c Seyfried, W. E.; Seewald, J. S.; Berndt, M. E.; Ding, Kang; Foustoukos, D. I. (September 2003). "Chemistry of hydrothermal vent fluids from the Main Endeavour Field, northern Juan de Fuca Ridge: Geochemical controls in the aftermath of June 1999 seismic events: VENT FLUIDS FROM MEF-JUAN DE FUCA RIDGE". Journal of Geophysical Research: Solid Earth. 108 (B9). doi:10.1029/2002JB001957.
  11. ^ Perkins, Sid (2001-07-14). "New Type of Hydrothermal Vent Looms Large". Science News. 160 (2): 21. doi:10.2307/4012715. JSTOR 4012715.
  12. ^ a b c d Clague, David A.; Martin, Julie F.; Paduan, Jennifer B.; Butterfield, David A.; Jamieson, John W.; Le Saout, Morgane; Caress, David W.; Thomas, Hans; Holden, James F.; Kelley, Deborah S. (2020). "Hydrothermal Chimney Distribution on the Endeavour Segment, Juan de Fuca Ridge". Geochemistry, Geophysics, Geosystems. 21 (6). Bibcode:2020GGG....2108917C. doi:10.1029/2020GC008917. ISSN 1525-2027. S2CID 218825220.
  13. ^ Colín-García, María (2016). "Hydrothermal vents and prebiotic chemistry: a review" (PDF). Boletín de la Sociedad Geológica Mexicana. 68 (3): 599–620. doi:10.18268/BSGM2016v68n3a13.
  14. ^ "Hydrothermal Vents" (PDF). School of Marine Science and Technology. Archived from the original (PDF) on 2017-09-16. Retrieved 2017-06-09.
  15. ^ Rathgeber, Christopher; Yurkova, Natalia; Stackebrandt, Erko; Schumann, Peter; Humphrey, Elaine; Beatty, J. Thomas; Yurkov, Vladimir (2006). "Metalloid Reducing Bacteria Isolated from Deep Ocean Hydrothermal Vents of the Juan de Fuca Ridge, Pseudoalteromonas telluritireducens sp. nov. and Pseudoalteromonas spiralis sp. nov". Current Microbiology. 53 (5): 449–456. doi:10.1007/s00284-006-0320-2. ISSN 0343-8651. PMID 17066332. S2CID 25680533.
  16. ^ Jamieson, John William; Hannington, Mark D.; Tivey, Margaret K.; Hansteen, Thor; Williamson, Nicole M. -B.; Stewart, Margaret; Fietzke, Jan; Butterfield, David; Frische, Matthias; Allen, Leigh; Cousens, Brian; Langer, Julia (2016-01-15). "Precipitation and growth of barite within hydrothermal vent deposits from the Endeavour Segment, Juan de Fuca Ridge". Geochimica et Cosmochimica Acta. 173: 64–85. Bibcode:2016GeCoA.173...64J. doi:10.1016/j.gca.2015.10.021. hdl:1912/7627. ISSN 0016-7037.
  17. ^ Thomson, Richard E.; Mihály, Steven F.; Rabinovich, Alexander B.; McDuff, Russell E.; Veirs, Scott R.; Stahr, Frederick R. (2003). "Constrained circulation at Endeavour ridge facilitates colonization by vent larvae". Nature. 424 (6948): 545–549. Bibcode:2003Natur.424..545T. doi:10.1038/nature01824. ISSN 1476-4687. PMID 12891356. S2CID 4343136.
  18. ^ a b Lee, Raymond W.; Robert, Katleen; Matabos, Marjolaine; Bates, Amanda E.; Juniper, S. Kim (2015-12-01). "Temporal and spatial variation in temperature experienced by macrofauna at Main Endeavour hydrothermal vent field". Deep Sea Research Part I: Oceanographic Research Papers. 106: 154–166. Bibcode:2015DSRI..106..154L. doi:10.1016/j.dsr.2015.10.004. ISSN 0967-0637.
  19. ^ Administration, US Department of Commerce, National Oceanic and Atmospheric. "What is a hydrothermal vent?". oceanservice.noaa.gov. Retrieved 2017-05-17.{{cite web}}: CS1 maint: multiple names: authors list (link)
  20. ^ "NatureServe Explorer 2.0". explorer.natureserve.org. Retrieved 2022-10-13.
  21. ^ Holst, Meike (2017). "Marine Mammal and Sea Turtle Sightings During a Survey of the Endeavour Segment of the Juan de Fuca Ridge, British Columbia". Canadian Field-Naturalist. 131 (2): 120–124. doi:10.22621/cfn.v131i2.1873 – via ResearchGate.
  22. ^ a b Zhou, Huaiyang; Li, Jiangtao; Peng, Xiaotong; Meng, Jun; Wang, Fengping; Ai, Yuncan (2009-06-01). "Microbial diversity of a sulfide black smoker in main endeavour hydrothermal vent field, Juan de Fuca Ridge". The Journal of Microbiology. 47 (3): 235–247. doi:10.1007/s12275-008-0311-z. ISSN 1976-3794. PMID 19557339. S2CID 23755913.
  23. ^ a b c Forget, Nathalie L.; Kim Juniper, S. (2013). "Free-living bacterial communities associated with tubeworm (Ridgeia piscesae) aggregations in contrasting diffuse flow hydrothermal vent habitats at the Main Endeavour Field, Juan de Fuca Ridge". MicrobiologyOpen. 2 (2): 259–275. doi:10.1002/mbo3.70. ISSN 2045-8827. PMC 3633350. PMID 23401293.
  24. ^ "Endeavour Hot Vents". ibis.geog.ubc.ca. Retrieved 2017-06-02.
  25. ^ a b Kashefi, Kazem; Lovley, Derek R. (2003-08-15). "Extending the Upper Temperature Limit for Life". Science. 301 (5635): 934. doi:10.1126/science.1086823. ISSN 0036-8075. PMID 12920290. S2CID 21189391.
  26. ^ Ortmann, Alice C.; Suttle, Curtis A. (2005-08-01). "High abundances of viruses in a deep-sea hydrothermal vent system indicates viral mediated microbial mortality". Deep Sea Research Part I: Oceanographic Research Papers. 52 (8): 1515–1527. Bibcode:2005DSRI...52.1515O. doi:10.1016/j.dsr.2005.04.002. ISSN 0967-0637.
  27. ^ "Education: Themes: Vent and Volcanoes: Background Information: NOAA Ocean Exploration". oceanexplorer.noaa.gov. Retrieved 2022-10-14.
  28. ^ a b c Juniper, S. Kim; Thornborough, Kate; Douglas, Karen; Hillier, Joy (October 2019). "Remote monitoring of a deep‐sea marine protected area: The Endeavour Hydrothermal Vents". Aquatic Conservation: Marine and Freshwater Ecosystems. 29 (S2): 84–102. doi:10.1002/aqc.3020. hdl:1828/11850. ISSN 1052-7613. S2CID 208074786.
  29. ^ a b c Menini, Elisabetta; Van Dover, Cindy Lee (2019-10-01). "An atlas of protected hydrothermal vents". Marine Policy. 108: 103654. doi:10.1016/j.marpol.2019.103654. ISSN 0308-597X. S2CID 202336223.
  30. ^ MBARI AUV D. Allan B.
  31. ^ Narwhal, The. "A deepsea 'oasis' is slated to become Canada's biggest protected area". The Narwhal. Retrieved 2022-11-06.
  32. ^ Juniper, S. Kim; Thornborough, Kate; Douglas, Karen; Hillier, Joy (2019). "Remote monitoring of a deep‐sea marine protected area: The Endeavour Hydrothermal Vents". Aquatic Conservation: Marine and Freshwater Ecosystems. 29 (S2): 84–102. doi:10.1002/aqc.3020. hdl:1828/11850. ISSN 1052-7613. S2CID 208074786.
  33. ^ Tunnicliffe, Verena and Richard Thomson. 1999.  The Endeavour Hot Vents Area: A Pilot Marine Protected Area in Canada's Pacific Ocean.  Fisheries and Oceans Canada, Sidney, BC.
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