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What am I investigating?

My research explores colonies of animals on the ocean floor, so that we can understand patterns of life in the deep sea that covers most of our world and make more informed choices for its future.

By studying marine life in "island-like" seafloor habitats such as hydrothermal vents, cold seeps, and whale-falls, my work examines interactions between ecology ("who does what"), biogeography ("who lives where"), and evolution ("who is related to whom") in the deep ocean.

I have published more than fifty research papers, worked on grants totalling more than £6.6 million in competitive funding, advised policymakers on the protection of deep-sea habitats, and produced a 4* "Impact Case Study" in the UK's REF2014 assessment.

Research projects

My recent projects have explored four areas:

* East Scotia Ridge, Southern Ocean

* Mid-Cayman Spreading Centre, Caribbean

* Mid-Atlantic Ridge north of the Azores

* the SW Indian Ridge

My work in these areas covers three main topics
(and for a full list of research papers, please see Publications):

(1) Global biogeography of deep-sea chemosynthetic environments

(e.g. Linse et al., 2019; Chapman et al., 2019; Chen et al., 2017; Copley et al., 2016; Anderson et al., 2016; Chen et al., 2015a; Roterman et al., 2013; Connelly et al., 2012; Rogers et al., 2012; Copley et al. 2007a)

Why do we find particular species of animals at hydrothermal vents in one region of the ocean but not at vents in another region? Why are some types of animals more widespread than others in habitats such as hydrothermal vents or cold seeps around the world? These are the big questions, and answering them should give us a better understanding of how species disperse and evolve in deep-sea habitats. Answering them also involves describing new species from the areas that we are exploring, and analysing their genetic code to determine how they are related to other species elsewhere.

Here are some of the new species that my colleagues and I have described from expeditions:
* Provanna beebei & Provanna cooki Nye, Linse, Copley & Chen 2019 (deep-sea vent snails)
* Dracogyra subfuscus & Lirapex politus Chen, Zhou, Wang & Copley 2017 (deep-sea vent snails)
* Pachycara caribbaeum Anderson, Somerville & Copley 2016 (deep-sea eelpout fish)
* Gigantopelta chessoia & Gigantopelta aegis Chen et al. 2015b ("giant" peltospirid snails)
* Paulasterias tyleri Mah et al. 2015 (seven-armed seastar)
* Chrysomallon squamiferum Chen, Linse, Copley & Rogers 2015 ("scaly-foot" snail)
* Osedax rogersi & Osedax crouchi Amon et al. 2014 (bone-eating "zombie" worms)
* Lebbeus virentova Nye, Copley, Plouviez & Van Dover 2013 ("green goolie" shrimp)
* Iheyaspira bathycodon Nye, Linse, Copley & Plouviez 2013 (deep-sea snail)
* Rimicaris hybisae Nye, Copley & Plouviez 2012 (world's deepest known vent shrimp)

(2) Spatial & temporal dynamics of faunal assemblages in insular & ephemeral deep-sea habitats

(e.g. Amon et al., 2017; Copley et al., 2016; Amon et al., 2013; Marsh et al., 2013; Marsh et al., 2012; Copley et al., 2007b; Copley et al., 1999; Copley et al., 1997)

Within a hydrothermal vent field, cold seep, or whale-fall, my goal is to understand what lives where and why. For example, why are some species abundant on vent chimneys, while other species only thrive at the edge of a vent field?

Unfortunately we can't stroll around the ocean floor as easily as ecologists do on rocky shores to investigate their patterns of life, so we are developing new techniques to study the microdistribution of animals in these environments, using high-definition cameras and the precision-control capabilities of the latest generation of remotely operated vehicles (ROVs).

(3) Life-history biology of species occupying insular & ephemeral deep-sea habitats

(e.g. Chen et al., 2018; Roterman et al., 2016; Amon et al., 2015; Marsh et al., 2015; Nye & Copley, 2014; Nye et al., 2013; Copley et al., 2007b; Copley & Young, 2006; Copley et al., 2003)

How do animals "hop" from vent to vent, or seep to seep, or whale skeleton to whale skeleton, in the deep ocean? The species we find in these island-like habitats on the ocean floor seem to have a variety of life cycles, types of larval development, and reproductive patterns. But are some features of their life-history biology "preadaptations" for success in these environments? And what are the consequences of differences in life-history biology for dispersal, gene flow, and ultimately biogeography?

My work in this area involves characterising the life-cycles of animals from hydrothermal vents, cold seeps, whale-falls, and wood-falls, in conjunction with studies of the genetics of their populations by colleagues around the world.

Research papers

(underlined names below indicate current / former supervised students / research team members)

Linse K, Copley JT, Connelly DP, Larter RD, Pearce DA, Polunin NVC, Rogers AD, Chen C, Clarke A, Glover AG, Graham AGC, Huvenne VAI, Marsh L, Reid WDK, Roterman CN, Sweeting CJ, Zwirglmaier K & Tyler PA (2019). The fauna of the Kemp Caldera and its upper bathyal hydrothermal vents (South Sandwich Arc, Antarctica). Royal Society Open Science, 6: 191501, doi:10.1098/rsos.191501 (open access).

Linse K, Nye V (joint lead authors), Copley JT & Chen C (2019). On the systematics and ecology of two new species of Provanna (Abyssochrysoidea: Provannidae) from deep-sea hydrothermal vents in the Caribbean Sea and Southern Ocean. Journal of Molluscan Studies, eyz024, doi:10.1093/mollus/eyz024.

Chapman A, Beaulieu S, Colaco A, Gebruk A, Hilario A, Kihara T, Ramirez-Llodra E, Sarrazin J, Tunnicliffe V, Amon D, Baker M, Boschen-Rose R, Chen C, Cooper I, Copley J, Corbari L, Cordes E, Cuvelier D, Duperron S, Du Preez C, Gollner S, Horton T, Hourdez S, Krylova E, Linse K, LokaBharathi PA, Marsh L, Matabos M, Mills S, Mullineaux L, Rapp H-T, Reid W, Rybakova (Goroslavskaya) E, Thomas T, Southgate S, Stohr S, Turner P, Watanabe H, Yasuhara M, Bates A (2019). sFDvent: a global trait database for deep-sea hydrothermal vent fauna, Global Ecology and Biogeography, 28: 1538-1551, doi:10.1111/geb.12975 (open access).

Fielding S, Copley JT & Mills RA (2019). Exploring Our Oceans: using the global classroom to develop ocean literacy. Frontiers In Marine Science, 6: 340, doi: 10.3389/fmars.2019.00340 (open access).

Copley J (2018). Providing evidence of "impact" from public engagement with research: a case study from the UK's Research Excellence Framework (REF). Research For All, 2(2): 230-243, doi:10.18546/RFA.02.2.03. (open access).

Chen C, Marsh L & Copley JT (2018). Is it sex in chains? Potential mating stacks in deep-sea hydrothermal vent snails. Plankton and Benthos Research, 13: 25-17, doi:10.3800/pbr.13.25 (open access).

Chen C, Zhou Y, Wang C & Copley JT (2017). Two new hot-vent peltospirid snails (Gastropoda: Neomphalina) from Longqi hydrothermal field, Southwest Indian Ridge. Frontiers in Marine Science, 4: 392, doi: 10.3389/fmars.2017.00392 (open access).

Amon DJ, Copley JT, Dahlgren TG, Horton T, Kemp KM, Rogers AD & Glover AG (2017). Observations of fauna attending wood and bone deployments from two seamounts on the Southwest Indian Ridge. Deep-Sea Research II, 136: 122-132, doi:10.1016/j.dsr2.2015.07.003.

Copley JT, Marsh L, Glover AG, Huhnerbach V, Nye VE, Reid WDK, Sweeting CJ, Wigham BD & Wiklund H (2016). Ecology and biogeography of megafauna and macrofauna at the first known deep-sea hydrothermal vents on the ultraslow-spreading Southwest Indian Ridge. Scientific Reports, 6: 38158, doi:10.1038/srep39158 (open access).
Press release

Roterman CN, Copley JT, Linse KT, Tyler PA & Rogers AD (2016). Connectivity in the cold: the comparative population genetics of vent-endemic fauna in the Scotia Sea, Southern Ocean. Molecular Ecology, 25: 1073-1088, doi:10.1111/mec.13541.

Chen C, Copley JT, Linse K, Rogers AD & Sigwart JD (2016). Dragon heart and dragon scales: anatomy of the 'scaly-foot gastropod' Chrysomallon squamiferum. Integrative and Comparative Biology, 56: E35 (meeting abstract).

Anderson ME, Somerville R & Copley JT (2016). A new species of Pachycara Zugmayer, 1911 (Teleostei: Zoarcidae) from deep-sea chemosynthetic environments in the Caribbean Sea. Zootaxa, 4066 (1): 071-077, doi:10.11646/zootaxa.4066.1.5 (open access).

Chen C, Linse K, Roterman CN, Copley J & Rogers AD (2015). A new genus of large hydrothermal vent-endemic gastropod (Neomphalina: Peltospiridae). Zoological Journal of the Linnean Society, 175: 319-335, doi:10.1111/zoj.12279.

Chen C, Copley JT, Linse K & Rogers AD (2015). Low connectivity between 'scaly-foot gastropod' (Mollusca: Peltospiridae) populations at hydrothermal vents on the Southwest Indian Ridge and the Central Indian Ridge. Organisms Diversity and Evolution, 15: 663-670, doi:10.1007/s13127-015-0224-8.

Chen C, Copley JT, Linse K, Rogers AD & Sigwart JD (2015). The heart of a dragon: 3D anatomical reconstruction of the 'scaly-foot' gastropod (Mollusca: Gastropoda: Neomphalina) reveals its extraordinary circulatory system. Frontiers in Zoology, 12: 13, doi:10.1186/s12983-015-0105-1 (open access).

Mah C, Linse K, Copley J, Marsh L, Rogers A, Clague D & Foltz D (2015). Description of a new family, new genus, and two new species of deep-sea Forcipulatacea (Asteroidea), including the first known sea-star from hydrothermal vent habitats. Zoological Journal of the Linnean Society, 174: 93-113, doi:10.1111/zoj.12229.
Press release

Chen C, Linse K, Copley JT & Rogers AD (2015). The 'scaly-foot gastropod': a new genus and species of hydrothermal vent-endemic gastropod (Neomphalina: Peltospiridae) from the Indian Ocean. Journal of Molluscan Studies, 81: 322-334, doi:10.1093/mollus/eyv013 (open access).

Amon DJ, Sykes D, Ahmed F, Copley JT, Kemp KM, Tyler PA, Young C & Glover AG (2015). Burrow forms, growth rates and feeding rates of wood-boring Xylophagaidae bivalves revealed by micro-computed tomography. Frontiers in Marine Science, 2: 10, doi:10.3389/fmars.2015.00010 (open access).

Marsh L, Copley J, Tyler PA & Thatje S (2015). In hot and cold water: differential life-history traits are key to success in contrasting thermal deep-sea environments. Journal of Animal Ecology, 84: 898-913, doi:10.1111/1365-2656.12337 (open access).
Press release

Chen C, Copley J, Linse K, Rogers A & Sigwart J (2015). How the mollusc got its scales: convergent evolution of the molluscan scleritome. Biological Journal of the Linnean Society, 114: 949-954, doi:10.1111/bij.12462.

Nye VE & Copley JT (2014). The reproductive biology of Lebbeus virentova (Caridea: Hippolytidae) at the Von Damm Vent Field, Mid-Cayman Speading Centre, Caribbean. Marine Biology, 161: 2371-2380, doi:10.1007/s00227-014-2512-9.

Van Dover C, Bell K, Marsh L, German C, John B, Cheadle M, Vecchione M, Amon D, Ball B, Copley J, Smart C, Fuller S, Phillips B, Cantner K, Auscavitch S & Ballard B (2014). Exploration of the Mid-Cayman Rise. Oceanography, 27: 32-33.

Amon DJ, Wiklund H, Dahlgren T, Copley JT, Smith CR, Jamieson AJ, & Glover AG (2014). Molecular taxonomy of Osedax (Annelida: Siboglinidae) in the Southern Ocean. Zoologica Scripta, 4: 405-417, doi:10.1111/zsc.12057.

Wheeler A, Murton B, Copley J, Lim A, Carlsson J, Collins P, Dorschel B, Green D, Judge M, Nye V, Benzie J, Antoniacomi A, Coughlan M & Morris K (2013). Moytirra: discovery of the first known deep-sea hydrothermal vent field on the slow-spreading Mid-Atlantic Ridge north of the Azores. Geochemistry Geophysics Geosystems, 14: 4170-4184, doi:10.1002/ggge.20243.

Collins PC, Kennedy B, Copley JT, Boschen RE, Fleming N, Forde J, Se-Jong J, Lindsay D, Marsh L, Nye VE, Patterson A, Watanabe H, Yamamoto H, Carlsson J & Thaler AD (2013). VentBase: Developing a consensus among stakeholders in the deep-sea regarding environmental impact assessment for deep-sea mining - a workshop report. Marine Policy, 42: 334-336, doi:10.1016/j.marpol.2013.03.002.

Roterman CN, Copley JT, Linse KT, Tyler PA & Rogers AD (2013). The biogeography of the yeti crabs (Kiwaidae) with notes on the phylogeny of the Chirostyloidea (Decapoda: Anomura). Proceedings of the Royal Society B, 280: 2013718, doi:0.1098/rspb.2013.0718 (open access).
Press release

Nye VE, Copley JT, Linse K & Plouviez S (2013). Iheyaspira bathycodon new species (Vetigastropoda: Trochoidea: Turbinidae: Skeneinae) from the Von Damm Vent Field, Mid-Cayman Spreading Centre, Caribbean. Journal of the Marine Biological Association of the UK, 94: 1017-1024, doi:10.1017/S002531541200082 (full pdf available here; publication is (c) Cambridge University Press).

Nye VE, Copley JT, Plouviez S & Van Dover CL (2013). A new species of Lebbeus (Crustacea: Decapoda: Caridea: Hippolytidae) from the Von Damm Vent Field, Caribbean Sea. Journal of the Marine Biological Association of the UK, 93: 741-751, doi:10.1017/S0025315412000884 (full pdf available here; publication is (c) Cambridge University Press).

Roterman CN, Copley JT, Linse KT, Tyler PA & Rogers AD (2013). Development of polymorphic microsatellite loci for three species of vent-endemic megafauna from deep-sea hydrothermal vents in the Scotia Sea, Southern Ocean. Conservation Genetics Resources, doi:10.1007/s12686-013-9921-9.

Nye VE, Copley JT & Tyler PA (2013). Spatial variation in the population structure and reproductive biology of Rimicaris hybisae (Caridea: Alvinocarididae) at hydrothermal vents on the Mid-Cayman Spreading Centre. PLoS ONE, 8(3): e60319, doi:10.1371/journal.pone.0060319 (open access).

Nye VE, Copley JT & Linse K (2013). A new species of Eualus Thallwitz, 1891 and new record of Lebbeus antarcticus (Hale, 1941) (Crustacea: Decapoda: Caridea: Hippolytidae) from the Scotia Sea. Deep-Sea Research II, 92: 145-156, doi:10.1016/j.dsr2.2013.01.022.

Marsh L, Copley JT, Huvenne VAI, Tyler PA & the NERC Deep-Platforms Team (2013). Getting the bigger picture: using precision Remotely Operated Vehicle (ROV) videography to construct high-definition mosaic images of newly discovered deep-sea hydrothermal vents in the Southern Ocean. Deep-Sea Research II, 92: 124-135, doi:10.1016/j.dsr2.2013.02.007.

Amon DJ, Glover AG, Wiklund H, Marsh L, Linse K, Rogers AD & Copley JT (2013). The discovery of a natural whale fall in the Antarctic deep sea. Deep-Sea Research II, 92: 87-96, doi:10.1016/j.dsr2.2013.01.028.
Press release

Boschen RE, Tyler PA & Copley JT (2013). Distribution, population structure, reproduction and diet of Ophiolimna antarctica (Lyman, 1879) from Kemp Caldera in the Southern Ocean. Deep-Sea Research II, 92: 27-35, doi:10.1016/j.dsr2.2013.02.005.

Aquilina A, Connelly DP, Copley JT, Green DRH, Hawkes JA, Hepburn LE, Huvenne VAI, Marsh L, Mills RA & Tyler PA (2013). Geochemical and visual indicators of hydrothermal fluid flow through a sediment-hosted volcanic ridge in the central Bransfield Basin. PLoS ONE, 8(1): e54686, doi:10.1371/journal.pone.0054686 (open access).

Marsh L, Copley JT, Huvenne VAI, Linse K, Reid WDK, Rogers AD, Sweeting CJ & Tyler PA (2012). Microdistribution of faunal assemblages at deep-sea hydrothermal vents in the Southern Ocean. PLoS ONE, 7(10): e48348, doi:10.1371/journal.pone.0048348 (open access).

Nye V, Copley J & Plouviez S (2012). A new species of Rimicaris (Crustacea: Decapoda: Caridea: Alvinocarididae) from hydrothermal vent fields on the Mid-Cayman Spreading Centre, Caribbean. Journal of the Marine Biological Association of the UK, 92: 1057-1072, doi:10.1017/S0025315411002001 (full pdf available here; publication is © Cambridge University Press).

Connelly DP, Copley JT (joint lead authors), Murton BJ, Stansfield K, Tyler PA, German CR, Van Dover CL, Amon D, Furlong M, Grindlay N, Hayman N, Huhnerbach V, Judge M, Le Bas T, McPhail S, Meier A, Nakamura K, Nye VE, Pebody M, Pedersen RB, Plouviez S, Sands C, Searle RC, Stevenson P, Taws S & Wilcox S (2012). Hydrothermal vent fields and chemosynthetic biota on the world's deepest seafloor spreading centre. Nature Communications, 3: 620, doi:10.1038/ncomms1636 (open access).
Press release

Rogers AD, Tyler PA, Connelly DP, Copley JT, James R, Larter RD, Linse K, Mills RA, Naveira-Garabato A, Pancost RD, Pearce DA, Polunin NVC, German CR, Shank T, Alker B, Aquilina A, Bennett SA, Clarke A, Dinley RJJ, Graham AGC, Green D, Hawkes JA, Hepburn L, Hilario A, Huvenne VAI, Marsh L, Ramirez-Llodra E, Reid WDK, Roterman CN, Sweeting CJ, Thatje S & Zwirglmaier K (2012). The discovery of new deep-sea hydrothermal vent communities in the Southern Ocean and implications for biogeography. PLoS Biology, 10(1): e1001234, doi:10.1371/journal.pbio.1001234 (open access).
Press release

Cuvelier D, Sarrazin J, Colaco A, Copley J, Glover A, Tyler P, Serrao Santos R & Desbruyeres D (2011). Community dynamics over 14 years at the Eiffel Tower hydrothermal edifice on the Mid-Atlantic Ridge. Limnology & Oceanography, 56: 1624-1640.

Cuvelier D, Sarradin P-M, Sarrazin J, Colaco A, Copley J, Desbruyeres D, Glover A, Serrao Santos R & Tyler P (2011). Hydrothermal faunal assemblages and habitat characterisation at the Eiffel Tower edifice (Lucky Strike, Mid-Atlantic Ridge). Marine Ecology, 32: 243-255.

Glover AG, Gooday AJ, Bailey BM, Billett DSM, Chevaldonne P, Colaco A, Copley J, Cuvelier D, Desbruyeres D, Kalogeropoulou V, Klages M, Lampadariou N, Lejeusne C, Mestre NC, Paterson GLJ, Perez T, Ruhl H, Sarrazin J, Soltwedel T, Soto EH, Thatje S, Tselepides A, Van Gaever S & Vanreusel A (2010). Temporal change in deep-sea benthic ecosystems: a review of the evidence from recent time-series studies. Advances in Marine Biology, 58: 1-95.

Vanreusel A, Fonseca G, Danavaro R, da Silva M, Esteves A, Ferrero T, Gad G, Galtsova V, Gambi C, da Fonseca Genevois V, Ingels J, Ingole B, Lampadariou N, Merckx B, Miljutin D, Miljutina M, Muthumbi A, Netto S, Portnova D, Radziejewska T, Raes M, Tchesunov A, Vanaverbeke J, Van Gaever S, Venekey V, Bezerra T, Flint H, Copley J, Pape E, Zeppilli D, Martinez P & Galeron J (2010). The contribution of deep-sea microhabitat heterogeneity to global nematode diversity. Marine Ecology, 31: 6-20.

Larkin KE, Ruhl HA, Bagley P, Benn A, Bett BJ, Billett DSM, Boetius A, Chevaldonne P, Colaco A, Copley J, Danovaro R, Escobar-Briones E, Glover A, Gooday AJ, Hughes JA, Kalogeropoulou V, Kitazato H, Kelly-Gerreyn BA, Klages M, Lampadariou N, Lejeusne C, Perez T, Priede IG, Rogers A, Sarradin PM, Sarrazin J, Soltwedel T, Soto EH, Thatje S, Tselepides A, van den Hove S, Tyler PA, Vanreusel A & Wenzhofer F (2010). Benthic biology time-series in the deep sea: indicators of change. In: Hall J, Harrison DE & Stammer D (eds), Proceedings of OceanObs'09: Sustained Ocean Observations and Information for Society, 2: 599-615 (European Space Agency Special Publication WPP-306).

Cuvelier D, Sarrazin J, Colaco A, Copley J, Desbruyeres D, Glover A, Tyler P & Serrao Santos R (2009). Distribution and spatial variation of hydrothermal faunal assemblages at Lucky Strike (Mid-Atlantic Ridge) revealed by high-resolution video image analysis. Deep-Sea Research I, 56: 2026-2040.

Copley JTP, Flint HC, Ferrero TJ & Van Dover CL (2007). Diversity of meiofauna and free-living nematodes in mussel beds at hydrothermal vents on the northern and southern East Pacific Rise. Journal of the Marine Biological Association of the UK, 87: 1141-1152, doi:10.1017/S0025315407055956 (full pdf available here; publication is (c) Cambridge University Press).

Copley JT (2007). Audio and video podcasts of lectures for campus-based students: production and evaluation of student use. Innovations in Education and Teaching International, 44: 387-399.

Copley JTP, Jorgensen PBK & Sohn RA (2007). Assessment of decadal-scale ecological change at a deep Mid-Atlantic hydrothermal vent and reproductive time-series in the shrimp Rimicaris exoculata. Journal of the Marine Biological Association of the UK, 87: 859-867, doi:10.1017/S0025315407056512 (full pdf available here; publication is (c) Cambridge University Press).

Flint HC, Copley JTP, Ferrero TJ & Van Dover CL (2006). Patterns of nematode diversity at hydrothermal vents on the East Pacific Rise. Cahiers de Biologie Marine, 47: 365-370.

Copley JTP & Young CM (2006). Seasonality and zonation in the reproductive biology and population structure of the shrimp Alvinocaris stactophila (Caridea: Alvinocarididae) at a Louisiana Slope cold seep. Marine Ecology Progress Series, 315: 199-209, doi:10.3354/meps315199

Tappin DR, Tyler P, Moran K, Copley J & McMurty G (2006). Dating submarine mass failures and relationships to tsunami generation: the use of multibeam bathymetry and seabed images, examples from the Pacific and Indian Oceans. Geophysical Research Abstracts, 8: 9175 (meeting abstract).

Copley JTP, Tyler PA, Van Dover CL & Philp S (2003). Spatial variation in the reproductive biology of Paralvinella palmiformis (Polychaeta: Alvinellidae) from a vent field on Juan de Fuca Ridge. Marine Ecology Progress Series, 255: 171-181, doi:10.3354/meps225171

Allen CE, Copley JT & Tyler P (2001). Lipid partitioning in the hydrothermal vent shrimp Rimicaris exoculata. PSZNI: Marine Ecology, 22: 241-253.

Ramirez Llodra E, Tyler PA & Copley JTP (2000). Reproductive biology of three caridean shrimp, Rimicaris exoculata, Chorocaris chacei and Mirocaris fortunata (Caridea: Decapoda), from hydrothermal vents. Journal of the Marine Biological Association of the UK, 80: 473-484.

Copley JTP, Tyler PA, Van Dover CL, Schultz A, Dickson P, Singh S & Sulanowska M (1999). Subannual temporal variation in faunal distributions at the TAG hydrothermal mound (26N, Mid-Atlantic Ridge). PSZNI: Marine Ecology, 20: 291-306.

Copley JTP, Tyler PA, Murton BJ & Van Dover CL (1997). Spatial and interannual variation in the faunal distribution at Broken Spur vent field (29N, Mid-Atlantic Ridge). Marine Biology, 129: 723-733.

Old school: video mosaic of hydrothermal vent chimney, c. 1994

Copley JTP, Tyler PA, Sheader M, Murton BJ & German CR (1996). Megafauna from sublittoral to abyssal depths along the Mid-Atlantic Ridge south of Iceland. Oceanologica Acta, 19: 549-559.

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