Molloy Deep

(Redirected from Molloy Hole)

The Molloy Deep (also known as the Molloy Hole) is a bathymetric feature in the Fram Strait, within the Greenland Sea[1] east of Greenland and about 160 km (100 mi) west of Svalbard. It is the location of the deepest point in the Arctic Ocean. The Molloy Deep, Molloy Hole, Molloy Fracture Zone, and Molloy Ridge were named after Arthur E. Molloy, a U.S. Navy research scientist who worked in the North Atlantic, North Pacific, and Arctic Oceans in the 1950s–1970s.[2][3][4][5][6][7][8]

Molloy Deep
Location
Molloy Deep is located in Arctic
Molloy Deep
Molloy Deep
Location of Molloy Deep
Coordinates79°8′12″N 2°49′0″E / 79.13667°N 2.81667°E / 79.13667; 2.81667
TypeOceanic trench
EtymologyArthur E. Molloy
Part ofFram Strait
Max. depth5,550 m (18,210 ft)
Water volume600 km3 (140 cu mi)

The outer rim of the trench is at a depth of 2,700 m (8,900 ft) and contains about 600 km2 (230 sq mi) inside the rim, descending to approximately 5,550 m (18,210 ft) at its greatest depth. The basin floor measures about 220 km2 (85 sq mi) and is the deepest point in the Arctic Ocean.[9][10] The only person to have reached the bottom of the Molloy Deep is American explorer Victor Vescovo as part of his Five Deeps Expedition.

Topography

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The Molloy Deep is a roughly rectangular, seismically active,[11] extensional,[12] sea-floor basin that lies between the northwestern tip of the Molloy Fracture Zone[13] (a right-lateral, strike-slip fault[14]) and the Spitsbergen Fracture Zone (also a right-lateral, strike-slip fault). These two fracture zones connect the actively spreading northern segment of the Mid-Atlantic Ocean ridge system called the Knipovich Ridge with the Lena Trough, an actively spreading mid-ocean ridge region north of the Spitsbergen Fracture Zone. The Lena Trough joins the southwestern end of the Arctic Ocean's Gakkel Ridge,[15] which is the slowest-spreading mid-ocean ridge on Earth and which stretches across the entire Arctic Oceans’ Eurasian Basin.[16][17][18]

Surveys

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DSSV Pressure Drop and DSV Limiting Factor at its stern

The Molloy Deep was discovered in September 1972 by the USNS Hayes (T-AGOR-16), the first of a new class of catamaran-hulled oceanographic research vessels. The Molloy Deep, Molloy Hole, Molloy Fracture Zone, and Molloy Ridge were named after Arthur E. Molloy, a U.S. Navy research scientist who worked in the North Atlantic, North Pacific and Arctic Oceans in the 1950s–1970s.[19]

Descents

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The only person to reach the bottom of the Molloy Deep is Victor Vescovo on 24 August 2019.[8][20] The Five Deeps Expedition leader and chief submersible pilot, Vescovo, descended into the Molloy Deep in the Deep-Submergence Vehicle Limiting Factor (a Triton 36000/2 model submersible) from the support ship, the Deep Submersible Support Vessel DSSV Pressure Drop.[21] The Five Deeps Expedition established the depth of the Molloy Deep as 5,550 m (18,210 ft) ±14 m (46 ft) by direct CTD pressure measurements.[22] This is shallower than previous estimations using earlier technology with less precise bathymetric methods.[23]

References

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  1. ^ "Fram Strait Bathymetry". Alfred Wegener Institute for Polar- and Marine Research. Archived from the original on 14 May 2013. Retrieved 2 October 2012.
  2. ^ IHO-IOC GEBCO Gazetteer of Undersea Feature Names (2018-06-25), available online at http://www.ngdc.noaa.gov/gazetteer/
  3. ^ Thiede, Jörn; Pfirman, Stephanie; Schenke, Hans-Werner; Reil, Wolfgang (1990). "Bathymetry of Molloy Deep: Fram Strait between Svalbard and Greenland". Marine Geophysical Researches. 12 (3). Springer: 197–214. Bibcode:1990MarGR..12..197T. doi:10.1007/BF02266713. S2CID 129241736.
  4. ^ Klenke, Martin; Schenke, Hans Werner (2002-07-01). "A new bathymetric model for the central Fram Strait". Marine Geophysical Research. 23 (4): 367–378. Bibcode:2002MarGR..23..367K. doi:10.1023/A:1025764206736. S2CID 128515547.
  5. ^ Bourke, Robert; Tunnicliffe, Mark; Newton, John; Paquette, Robert; Manley, Tom (1987-06-30). "Eddy near the Molloy Deep revisited". Journal of Geophysical Research. 92 (C7): 6773–6776. Bibcode:1987JGR....92.6773B. doi:10.1029/JC092iC07p06773.
  6. ^ Thiede, Jörn; Pfirman, Stephanie; Schenke, Hans Werner; Reil, Wolfgang (1990-08-01). "Bathymetry of Molloy Deep: Fram Strait between Svalbard and Greenland". Mar. Geophys. Res. 12 (3): 197–214. Bibcode:1990MarGR..12..197T. doi:10.1007/BF02266713. S2CID 129241736.
  7. ^ Freire, Francis; Gyllencreutz, Richard; Jafri, Rooh; Jakobsson, Martin (2014-03-31). "Acoustic evidence of a submarine slide in the deepest part of the Arctic, the Molloy Hole". Geo-Marine Letters. 34 (4): 315–325. Bibcode:2014GML....34..315F. doi:10.1007/s00367-014-0371-5. S2CID 130008727.
  8. ^ a b "Five Deeps Expedition is complete after historic dive to the bottom of the Arctic Ocean" (PDF) (Press release).
  9. ^ Freire, Francis; Gyllencrentz, Richard; Jafri, Rooh Ullah; Jakobsson, Martin (April 2014). "Acoustic evidence of a submarine slide in the deepest part of the Arctic, the Molloy Hole". Geo-Marine Letters. 34 (4): 315–325. Bibcode:2014GML....34..315F. doi:10.1007/s00367-014-0371-5. S2CID 130008727.
  10. ^ Jakobsson, Martin; et al. (2012). "The International Bathymetric Chart of the Arctic Ocean (IBCAO) Version 3.0". Geophys Res Lett. 39 (12): 1–6. Bibcode:2012GeoRL..3912609J. doi:10.1029/2012GL052219. hdl:2445/175672. S2CID 55994905.
  11. ^ Läderach, C.; Schlindwein, V.; Schenke, H.-W.; Jokat, W. (March 2011). "Seismicity and active tectonic processes in the ultra-slow spreading Lena Trough, Arctic Ocean". Geophysical Journal International. 184 (3): 1354–1370. Bibcode:2011GeoJI.184.1354L. doi:10.1111/j.1365-246X.2010.04926.x. S2CID 130643353.
  12. ^ Baturin, D.G. (1990). "Structure and Geodynamics of the Molloy Transform Fracture Zones in the Mid-Ridge System of the Norway–Greenland Oceanic Basin". Okeanologiya. 30 (3): 436–443.
  13. ^ JThiede, J.; et al. (1990). "Bathymetry of Molloy Deep: Fram Strait Between Svalbard and Greenland". Marine Geophysical Researches. 12 (3): 197–214. Bibcode:1990MarGR..12..197T. doi:10.1007/bf02266713. S2CID 129241736.
  14. ^ Chamov, N. P.; et al. (2010). "Structure and composition of the sedimentary cover in the Knipovich Rift valley and Molloy Deep (Norwegian-Greenland basin)". Lithology and Mineral Resources. 45 (6): 532–554. Bibcode:2010LitMR..45..532C. doi:10.1134/S0024490210060039. S2CID 56258200.
  15. ^ "Do You Know the Different Types of Faults?".
  16. ^ Cochran, James R.; Kurras, Gregory J.; Edwards, Margo H.; Coakley, Bernard J. (February 2003). "The Gakkel Ridge: Bathymetry, gravity anomalies, and crustal accretion at extremely slow spreading rates". Journal of Geophysical Research. 108 (B2): 2116. Bibcode:2003JGRB..108.2116C. doi:10.1029/2002JB001830.
  17. ^ Nikishin, A.M.; Gaina, C.; Petrov, E.I.; Malyshev, N.A.; Freiman, S.I. (October 2018). "Eurasia Basin and Gakkel Ridge, Arctic Ocean: Crustal asymmetry, ultra-slow spreading and continental rifting revealed by new seismic data". Tectonophysics. 746: 64–82. Bibcode:2018Tectp.746...64N. doi:10.1016/j.tecto.2017.09.006. hdl:10852/72327. S2CID 133976322.
  18. ^ Piskarev, Alexey; Elkina, Daria (10 April 2017). "Giant caldera in the Arctic Ocean: Evidence of the catastrophic eruptive event". Scientific Reports. 7 (1): 46248. Bibcode:2017NatSR...746248P. doi:10.1038/srep46248. PMC 5385544. PMID 28393928. S2CID 17612035.
  19. ^ Perry, R.K. (1986). "Bathymetry". In Hurdle, Burton G. (ed.). The Nordic Seas. Springer-Verlag. pp. 227–28. doi:10.1007/978-1-4615-8035-5_9. ISBN 978-0-387-96241-2. LCCN 85025179.
  20. ^ Amos, Jonathan (2019-09-09). "Victor Vescovo: Adventurer reaches deepest ocean locations". BBC News. Archived from the original on 2024-05-20. Retrieved 2019-09-10.
  21. ^ "Full Ocean Depth Submersible LIMITING FACTOR". fivedeeps.com. Retrieved 2019-10-10.
  22. ^ Five Deeps Expedition (2019-09-09). "Five Deeps Expedition is complete after historic dive to the bottom of the Arctic Ocean" (PDF). Retrieved 2019-10-10.
  23. ^ Bongiovanni, Cassandra; Stewart, Heather A.; Jamieson, Alan J. (2021-05-05). "High-resolution multibeam sonar bathymetry of the deepest place in each ocean". Geoscience Data Journal. 9 (1): 108–123. doi:10.1002/gdj3.122.