Pako Guyot

The guyot is also known as Caiwei{{Cite journal|title=Ophiuroids from the Caiwei(Pako) guyot in the northwest Pacific|journal=EGU General Assembly Conference Abstracts|volume=17|pages=8190|author1=Zhang, Dongsheng |author2=Lu, Bo |author3=Wang, Xiaogu |author4=Lin, Shiquan |author5=Wang, Chunsheng |date=April 2015|bibcode=2015EGUGA..17.8190Z}} or Pallada after the {{ship|Russian frigate|Pallada}}.{{Cite web|url=http://guyot.ocean.ru/baza-dannykh/gajot-pallada.html|series=Магеллановы горы (Тихий океан)|publisher=Shirshov Institute of Oceanology|title=Гайот Паллада (15°18.00' N 155°00.00' E )|language=ru-ru|access-date=2018-10-06}}

Pako Guyot reaches a depth of {{convert|1350|m}}. It has dimensions of {{convert|40|x|65|km}} and features a summit plateau {{convert|2056|km2}} wide{{cite journal |last1=Okamoto |first1=Nobuyuki |last2=Usui |first2=Akira |title=Regional Distribution of Co-Rich Ferromanganese Crusts and Evolution of the Seamounts in the Northwestern Pacific |journal=Marine Georesources & Geotechnology |date=4 March 2014 |volume=32 |issue=3 |page=194 |doi=10.1080/1064119x.2013.877110 |bibcode=2014MGG....32..187O |s2cid=128677808 |language=en |issn=1064-119X}} at a depth of {{convert|1500|-|1650|m}}{{cite journal |last1=Yang |first1=Zifei |last2=Qian |first2=Qiankun |last3=Chen |first3=Min |last4=Zhang |first4=Run |last5=Yang |first5=Weifeng |last6=Zheng |first6=Minfang |last7=Qiu |first7=Yusheng |title=Enhanced but highly variable bioturbation around seamounts in the northwest Pacific |journal=Deep Sea Research Part I: Oceanographic Research Papers |date=February 2020 |volume=156 |pages=103190 |doi=10.1016/j.dsr.2019.103190 |bibcode=2020DSRI..15603190Y |s2cid=213393633 |url=https://www.sciencedirect.com/science/article/pii/S096706371930336X |language=en |issn=0967-0637}} with a shape corresponding to an irregular rectangle-triangle. With an area of {{convert|13680|km2}}, Pako Guyot is the third-largest guyot on Earth, only behind Koko Seamount and Suiko Seamount.{{cite journal |last1=Harris |first1=P.T. |last2=Macmillan-Lawler |first2=M. |last3=Rupp |first3=J. |last4=Baker |first4=E.K. |title=Geomorphology of the oceans |journal=Marine Geology |date=June 2014 |volume=352 |pages=4–24 |doi=10.1016/j.margeo.2014.01.011 |bibcode=2014MGeol.352....4H |url=https://www.sciencedirect.com/science/article/pii/S0025322714000310 |language=en |issn=0025-3227}} The summit plateau is covered by sediments {{convert|25|-|100|m}} thick including foraminiferal ooze, while the flanks feature small-scale features such as depressions, ridges and trenches. Former reefs occur on the seamount and during the Cretaceous and Eocene left mudstones and limestones on the seamount. Later, pelagic limestones were emplaced on them. A {{convert|65|km2}} large area on the northwestern corner of Pako Guyot's summit plateau is free of sediments.

The guyot is part of the Magellan Seamounts.{{cite journal |last1=Lee |first1=Tae-Gook |last2=Hein |first2=James R. |last3=Lee |first3=Kiehwa |last4=Moon |first4=Jai-Woon |last5=Ko |first5=Young-Tak |title=Sub-seafloor acoustic characterization of seamounts near the Ogasawara Fracture Zone in the western Pacific using chirp (3–7kHz) subbottom profiles |journal=Deep Sea Research Part I: Oceanographic Research Papers |date=October 2005 |volume=52 |issue=10 |page=1934 |doi=10.1016/j.dsr.2005.04.009 |language=en |issn=0967-0637 |bibcode=2005DSRI...52.1932L}} The seamount was volcanically active during the Cretaceous-Paleogene{{cite journal |last1=Zhao |first1=Bin |last2=Wei |first2=Zhenquan |last3=Yang |first3=Yong |last4=He |first4=Gaowen |last5=Zhang |first5=Heng |last6=Ma |first6=Weilin |title=Sedimentary characteristics and the implications of cobalt-rich crusts resources at Caiwei Guyot in the Western Pacific Ocean |journal=Marine Georesources & Geotechnology |date=10 August 2019 |volume=38 |issue=9 |page=2 |doi=10.1080/1064119X.2019.1648615 |s2cid=202188742 |issn=1064-119X}} 91.3 million years ago{{cite journal |last1=Lee |first1=Tae-Gook |last2=Lee |first2=Kiehwa |last3=Hein |first3=James R. |last4=Moon |first4=Jai-Woon |title=Geophysical investigation of seamounts near the Ogasawara Fracture Zone, western Pacific |journal=Earth, Planets and Space |date=March 2009 |volume=61 |issue=3 |page=320 |doi=10.1186/bf03352914 |bibcode=2009EP&S...61..319L |language=en |issn=1343-8832|doi-access=free }} and may have formed on a hotspot together with Ioah Guyot and Vlinder Guyot;{{cite journal |last1=Lee |first1=Tae-Gook |last2=Moon |first2=Jai-Woon |last3=Jung |first3=Mee-Sook |title=Three-dimensional flexure modelling of seamounts near the Ogasawara Fracture Zone in the western Pacific |journal=Geophysical Journal International |date=April 2009 |volume=177 |issue=1 |page=249 |doi=10.1111/j.1365-246X.2008.04054.x |bibcode=2009GeoJI.177..247L |language=en |issn=0956-540X|doi-access=free }} a late phase of volcanism may have taken place in the Paleocene-Eocene.{{cite journal |last1=Mel’nikov |first1=M. E. |last2=Pletnev |first2=S. P. |last3=Anokhin |first3=V. M. |last4=Sedysheva |first4=T. E. |last5=Ivanov |first5=V. V. |title=Volcanic edifices on guyots of the Magellan Seamounts (Pacific Ocean) |journal=Russian Journal of Pacific Geology |date=November 2016 |volume=10 |issue=6 |page=439 |doi=10.1134/s1819714016060038 |bibcode=2016RuJPG..10..435M |s2cid=132364693 |language=en |issn=1819-7140}} The hotspots that formed Pako Guyot were located in what is today French Polynesia.{{cite journal |last1=Zhao |first1=Bin |last2=Wei |first2=Zhenquan |last3=Yang |first3=Yong |last4=He |first4=Gaowen |last5=Zhang |first5=Heng |last6=Ma |first6=Weilin |title=Sedimentary characteristics and the implications of cobalt-rich crusts resources at Caiwei Guyot in the Western Pacific Ocean |journal=Marine Georesources & Geotechnology |date=20 October 2020 |volume=38 |issue=9 |pages=1037–1045 |doi=10.1080/1064119X.2019.1648615 |bibcode=2020MGG....38.1037Z |s2cid=202188742 |url=https://www.tandfonline.com/doi/full/10.1080/1064119X.2019.1648615 |issn=1064-119X}}

Volcanic rocks dredged from Pako are of sodium-potassium hawaiitic and trachybasaltic composition and geochemically resemble these erupted by the Rarotonga hotspot.{{cite journal |last1=Koppers |first1=Anthony A. P. |last2=Staudigel |first2=Hubert |last3=Pringle |first3=Malcolm S. |last4=Wijbrans |first4=Jan R. |title=Short-lived and discontinuous intraplate volcanism in the South Pacific: Hot spots or extensional volcanism? |journal=Geochemistry, Geophysics, Geosystems |date=October 2003 |volume=4 |issue=10 |page=1089 |doi=10.1029/2003gc000533 |language=en |issn=1525-2027 |bibcode=2003GGG.....4.1089K|s2cid=131213793 }} Clays with Cenomanian-age radiolarian fossils cover the entire lower slopes of Pako Guyot.{{cite journal |last1=Pletnev |first1=S. P. |title=Main Types of Aptian–Cenomanian Sedimentary Rocks on Guyots of the Magellan Mountains, Pacific Ocean |journal=Russian Journal of Pacific Geology |date=1 September 2019 |volume=13 |issue=5 |pages=436–445 |doi=10.1134/S1819714019050087 |bibcode=2019RuJPG..13..436P |s2cid=203654288 |url=https://link.springer.com/article/10.1134/S1819714019050087 |language=en |issn=1819-7159}}

Corals and squat lobsters have been found on the seamount.{{cite journal |last1=DONG |first1=DONG |last2=LI |first2=XINZHENG |last3=LU |first3=BO |last4=WANG |first4=CHUNSHENG |title=Three squat lobsters (Crustacea: Decapoda: Anomura) from tropical West Pacific seamounts, with description of a new species of Uroptychus Henderson, 1888 |journal=Zootaxa |date=24 August 2017 |volume=4311 |issue=3 |pages=389 |doi=10.11646/zootaxa.4311.3.4}} Ophiuroids, most of which are symbiotic with corals and sponges, live on the seamount and its flanks. Diverse communities including brittle stars, corals, fish, sea anemones, sea cucumbers, sea lilies, sea urchins, shrimp and starfish have been found at its feet, where organic matter accumulates. Ammonites lived on the seamount during the Cretaceous.{{cite journal |last1=Zakharov |first1=Yuri D. |last2=Melnikov |first2=Mikhael E. |last3=Popov |first3=Alexander M. |last4=Pletnev |first4=Sergej P. |last5=Khudik |first5=Vladimir D. |last6=Punina |first6=Tatiana A. |title=Cephalopod and brachiopod fossils from the Pacific: Evidence from the Upper Cretaceous of the Magellan Seamounts |journal=Geobios |date=January 2012 |volume=45 |issue=1 |pages=145–156 |doi=10.1016/j.geobios.2011.11.011 |bibcode=2012Geobi..45..145Z |url=https://www.sciencedirect.com/science/article/pii/S0016699511001057 |language=en |issn=0016-6995}}

The seamount features substantial deposits of ferromanganese and phosphorite ores. In 2014, China obtained a contract with the International Seabed Authority allowing for exploration of Pako Guyot for cobalt crusts.{{cite journal |last1=Zhao |first1=Bin |last2=Wei |first2=Zhenquan |last3=Yang |first3=Yong |last4=He |first4=Gaowen |last5=Zhang |first5=Heng |last6=Ma |first6=Weilin |title=Sedimentary characteristics and the implications of cobalt-rich crusts resources at Caiwei Guyot in the Western Pacific Ocean |journal=Marine Georesources & Geotechnology |date=10 August 2019 |volume=38 |issue=9 |page=1 |doi=10.1080/1064119X.2019.1648615 |bibcode=2020MGG....38.1037Z |s2cid=202188742 |issn=1064-119X}}

• Ita Mai Tai

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Category:Seamounts of the Pacific Ocean

Category:Cretaceous volcanoes

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