Geologists Seamounts

Geologists Seamounts
Bathymetric map of the south-west Geologists Seamounts
Location
LocationNorth Pacific Ocean
Coordinates18°40′N 157°40′W / 18.667°N 157.667°W / 18.667; -157.667[1]
Geology
Age of rockCretaceous

Geologists Seamounts (alternatively were named South West Hawaii Group[2]) are a cluster of seamounts in the Pacific Ocean, located mainly 100 miles (160 km) south of Oahu, Hawaii[3] and 100–200 kilometres (62–124 mi)[4] south-west from Big Island (Hawaiʻi).[5] Clockwise from north they are named Perret, Jaggar, McCall, Pensacola, Daly, Swordfish, Cross, Washington and Ellis.[6] The Kauluakalana seamount to the north of Oahu on the far side of the Hawaiian chain to the other seamounts of the cluster, and south-east of the Musicians Seamounts has reason to be regarded as part of the Geologists Seamounts,[7] but would not so be grouped logically by the former name for the cluster.

Geology[edit]

The seamounts developed during the Cretaceous,[8] about 80 million years ago, and there is no geological relationship to the neighbouring Hawaiian Islands.[4] There is about contemporaneous timing with the formation of the Musicians Seamounts to the north-west of Oahu and Hawaiʻi, from the limited sampling and analysis to date.[9] Ages that have been obtained include 80.5 Ma for Kauluakalana, 84.5 Ma for Cross and 82.7 Ma for McCall.[7] Rocks dredged from the seamounts include iron-manganese crusts, carbonates and basalts.[10]

Ecology[edit]

Corals and sponges have been recorded at the south-western Swordfish Seamount at a depth of 1,071 m (3,514 ft) with plexauridae, alcyonacea, and coralliidae corals.[11] The deeper coral community on Ellis Seamount at a depth of 2,135 m (7,005 ft) was less diverse with bamboo corals dominant.[11]

References[edit]

  1. ^ Kelley et al. 2020, p. 5.
  2. ^ Wessel, P.; Keating, B. H. (10 February 1994). "Temporal variations of flexural deformation in Hawaii". Journal of Geophysical Research: Solid Earth. 99 (B2): 2751. doi:10.1029/93JB02876.
  3. ^ "Project instruction for EX-15-04 Leg 3 : CAPSTONE NWHI Exploration, Leg III". NOAA. 2015. p. 3. Retrieved 25 March 2018.
  4. ^ a b Wessel, P.; Lyons, S. (10 October 1997). "Distribution of large Pacific seamounts from Geosat/ERS-1: Implications for the history of intraplate volcanism". Journal of Geophysical Research: Solid Earth. 102 (B10): 22467. doi:10.1029/97JB01588.
  5. ^ Wessel 1998, p. 403.
  6. ^ "APPLICATION BRIEFS 2008" (PDF). University of Hawaii. 2008. p. 15. Retrieved 25 March 2018.
  7. ^ a b Clouard, V.; Bonneville, A. (2005). "Ages of seamounts, islands, and plateaus on the Pacific plate" (PDF). In Foulger, G.R.; Natland, J.H.; Presnall, D.C.; Anderson, D.L. (eds.). Plates, plumes, and paradigms:Geological Society of America Special Paper 388. Geological Society of America. pp. 71–90. doi:10.1130/0-8137-2388-4.71. ISBN 978-0-8137-2388-4. Retrieved 25 January 2024.pp=78, 84, 85
  8. ^ Wessel 1998, p. 405.
  9. ^ Hillier, J. K. (February 2007). "Pacific seamount volcanism in space and time". Geophysical Journal International. 168 (2): 877–889. doi:10.1111/j.1365-246X.2006.03250.x. ISSN 0956-540X.
  10. ^ Kelley et al. 2020, pp. 24, 35.
  11. ^ a b Kelley et al. 2020, pp. 24, 33.

Sources[edit]