The Dordrecht Deep is located in the Diamantina Trench southwest of Perth, Western Australia. The Diamantina Trench is in the eastern part of the larger Diamantina Fracture Zone, which stretches 1,900 kilometres (1,200 mi)[1] from the Ninety East Ridge to the Naturaliste Plateau, off the lower part of Southwest Australia.[2][3][4] It is one of the deepest points (surpassed by the Sunda Trench) in the Indian Ocean at 7,079 m (23,225 ft).[5] It is located about 1,125 kilometres (699 mi) west-southwest of Perth at 35°S 104°E / 35°S 104°E / -35; 104.

2019 bathymetry Diamantina Trench

It was discovered in 1960.[6] A subsequent survey in 1961 by the Australian oceanographic survey ship HMAS Diamantina (K377) confirmed the bathymetry and conducted a scientific survey. The trench (and the Fracture Zone) was named after her.[1] Dordrecht was the name of a vessel of the Dutch East India Company, which explored the Australian west coast in 1619 and discovered the Houtman Abrolhos.

2019 ultra-deep-sea lander descent edit

 
Two of the ultra-deep-sea landers used by the Five Deeps Expedition

To resolve the debate regarding the deepest point of the Indian Ocean, the Diamantina Fracture Zone was surveyed by the Five Deeps Expedition in March 2019 by the Deep Submersible Support Vessel DSSV Pressure Drop, equipped with a Kongsberg SIMRAD EM124 multibeam echosounder system. Using the multibeam echosounder system and direct measurement by an ultra-deep-sea lander a maximum water depth of 7,019 m (23,028 ft) ±17 m (56 ft) at 33°37′52″S 101°21′14″E / 33.63111°S 101.35389°E / -33.63111; 101.35389 for the Dordrecht Deep was recorded.[7] This was shallower than previously thought,[8][9] and confirmed that the Sunda Trench, rather than the Diamantina Fracture Zone, contains the deepest point in the Indian Ocean. The gathered data will be donated to the GEBCO Seabed 2030 initiative.[10][11] The expedition aimed to thoroughly map and visit the deepest points of all five of the world's oceans by the end of September 2019, at which it was successful.[12][13]

See also edit

References edit

  1. ^ a b "HMAS Diamantina, 412 Stanley St, South Brisbane, QLD, Australia (Place ID 106018)". Australian Heritage Database. Australian Government.
  2. ^ Stow, D. A. V. (2006), Oceans: an illustrated reference, Chicago: University of Chicago Press, ISBN 0226776646 Page 127 for map of Indian Ocean and pp. 34-37 regarding trenches - but due to the recent discovery, some texts and maps are yet to include the feature.
  3. ^ "Record Indian Ocean Depth Charted". The Canberra Times. Australian Capital Territory, Australia. 11 February 1960. p. 18. Retrieved 5 February 2020 – via Trove.
  4. ^ Australia. Department of Commerce and Agriculture (1961-03-01), "FRIGATES' CSIRO RESEARCH CREISES (1 March 1961)", Fisheries News-letter, 20 (3), The Division, ISSN 0248-076X
  5. ^ "ETOPO1 Global Relief Model". NOAA. Retrieved 2012-03-07
  6. ^ Gorton, John (1960-02-10), H.M.... ship's important discovery, retrieved 6 January 2020
  7. ^ "Science Landers Flere, Skaff & Closp". fivedeeps.com. Retrieved 22 October 2019.
  8. ^ Hydro International.com (18 June 2019). "Exploring the Deepest Points on Planet Earth". hydro-international.com. Retrieved June 20, 2019.
  9. ^ Five Deeps Expedition (16 April 2019). "Deep sea pioneermakes history again as first human to dive to the deepest point in the Indian Ocean, the Java Trench" (PDF). fivedeeps.com. Retrieved June 20, 2019.
  10. ^ "The Nippon Foundation-GEBCO Seabed 2030 Project". Archived from the original on 2019-06-16. Retrieved 2020-04-21.
  11. ^ "Major partnership announced between The Nippon Foundation-GEBCO Seabed 2030 Project and The Five Deeps Expedition". gebco.net. 11 March 2019. Archived from the original on 2019-06-19. Retrieved June 19, 2019.
  12. ^ "Home". fivedeeps.com. Retrieved January 9, 2019.
  13. ^ Bongiovanni, Cassandra; Stewart, Heather A.; Jamieson, Alan J. (2022). "High‐resolution multibeam sonar bathymetry of the deepest place in each ocean". Geoscience Data Journal. 9. Royal Meteorological Society: 108–123. doi:10.1002/gdj3.122. S2CID 235548940.

External links edit

35°00′S 104°00′E / 35.000°S 104.000°E / -35.000; 104.000