Magellan Seamounts
{{Short description|Seamount chain in Pacific Ocean}}
{{Infobox seamount
| name = Magellan Seamounts
| depth =
| height =
| summit_area =
| location = Pacific Ocean
| group =
| coordinates =
| country =
| type = Seamount chain
| age = {{fossil range|121|20}}
| discovered =
| map = {{OSM Location map
| coord ={{coord|15.6|155.2}}
| caption =
| float = center
| zoom= 3
| width= 290
| height= 290
| markD = Yellow pog.svg
| mark-sizeD = 9
| label-sizeD = 8
| label-colorD = black
| label-posD = right
| arc-latA = 17.5
| arc-lonA =149.2
| arc-angleA=40
| arc-gapA=0.5
| arc-radiusA=2.0
| arc-text-colorA=white
| arc-text-sizeA=12
| arc-textA=Magellan
| arc-latB = 16.2
| arc-lonB =147.2
| arc-angleB=40
| arc-gapB=0.5
| arc-radiusB=2.0
| arc-text-colorB=white
| arc-text-sizeB=12
| arc-textB=Seamounts
| mark-coord = {{coord|15.0|154.0}}
| mark-title = Magellan Seamounts
| mark-description = Magellan Seamounts are defined to be in a rectangle 11.0,151.0 to 18.0,157.0
| label1 = Govorov Guyot
| label-offset-y1=-7
| mark-coord1 = {{coord|18|00.25|N|151|13.50|E}}
| mark-title1 = Govorov Guyot
| mark-description1 = Govorov Guyot (121 ± 2.8 to 98.5 ± 1.4 Ma) is a member of the Magellan Seamounts
| label3 = Vlinder Guyot
| label-offset-y3=-4
| mark-coord3= {{coord|16|57.61|N|154|16.63|E}}
| mark-title3 = Vlinder Guyot
| mark-description3 = Vlinder Guyot (95 Ma) is a member of the Magellan Seamounts
| label4 = Pako Guyot
| label-offset-y4=-4
| mark-coord4= {{coord|15|42.83|N|155|11.96|E}}
| mark-title4 = Pako Guyot
| mark-description4 = Pako Guyot (92 Ma) is a member of the Magellan Seamounts
| label5 = Ioah Seamount
| label-offset-y5=-4
| mark-coord5= {{coord|14|06.00|N|156|08.40|E}}
| mark-title5 = Ioah Seamount
| mark-description5 = Ioah Seamount (87 Ma) is a member of the Magellan Seamounts
| label2 = Ita Mai Tai Guyot
| mark-coord2 = {{coord|12|51.00|N|156|46.20|E}}
| mark-title2 = Ita Mai Tai Guyot
| label-offset-y2=0
| mark-description2 = Ita Mai Tai Guyot (118 Ma) is a member of the Magellan Seamounts
}}
| relief =
| map_size =
| map_caption =
| label =
| image_caption = Area of Magellan Seamounts (clicking on map enables mouse over of the seamounts)
| image =
}}
The Magellan Seamounts (also known as Magellan Seamount Group and previously called Magellan Rise[https://www.marineregions.org/gazetteer.php?p=details&id=32357 Marine Gazetter:deleted entry record Magellan Rise]{{cite journal|last1=Zakharov|first1=Yu D.|last2=Pletnev|first2=S. P.|last3=Mel’nikov|first3=M. E.|last4=Smyshlyaeva|first4=O. P.|last5=Khudik|first5=V. D.|last6=Evseev|first6=G. A.|last7=Punina|first7=T. A.|last8=Safronov|first8=P. P.|last9=Popov|first9=A. M.|title=The first finds of cretaceous belemnites from the Magellan Rise, Pacific Ocean|journal=Russian Journal of Pacific Geology|date=1 February 2007|volume=1|issue=1|page=30|doi=10.1134/S1819714007010058|bibcode=2007RuJPG...1...29Z |s2cid=129404630|language=en|issn=1819-7140}} ) stretch from the Mariana Trench to Ita Mai Tai Guyot.{{cite journal|language=ru|first1=M. E.|last1=Mel'nikov|first2=S. P.|last2=Pletnev|first3=I. A.|last3=Basov|title=New Geological and Paleontological Data on Fedorov Guyot, Magellan Seamounts, Pacific|journal=Tikhookean. Geol.|volume=25|issue=1|pages=3–13|year=2006}} Geological studies have demonstrated unique features with implications on understanding of ocean island basalt volcanism.{{cite journal|first1=Xun |last1=Wei|first2= Yan |last2=Zhang|first3= Xue-Fa |last3=Shi|first4= Paterno R |last4=Castillo|first5= Yi-Gang |last5=Xu|first6= Quan-Shu |last6=Yan|first7= Ji-Hua |last7=Liu|title= Co-Occurrence of HIMU and EM1 Components in a Single Magellan Seamount: Implications for the Formation of West Pacific Seamount Province|journal=Journal of Petrology| volume=63 |issue=4 |year=2022 |doi=10.1093/petrology/egac022 }} Contracts exist with the International Seabed Authority to exploit the areas potential mineral wealth.{{cite web|url=https://www.isa.org.jm/exploration-contracts/cobalt-rich-ferromanganese-crusts/ |title= International Seabed Authority Minerals: Cobalt-rich Ferromanganese Crusts Contractors|date= 17 March 2022|access-date=5 March 2023}}
Geography
The Magellan Seamounts extend from {{coord|11.0|N|151.0|E|display=inline}} to {{coord|18.0|N|157.0|E|display=inline}} [https://www.marineregions.org/gazetteer.php?p=details&id=7375 Marine Gazetteer:Magellan Seamounts]
They include:
- Govorov Guyot{{cite journal|last1=Peretyazhko |first1=IS |last2= Savina |first2=EA |title=Cretaceous intraplate volcanism of Govorov Guyot and formation models of the Magellan seamounts Pacific Ocean|journal= International Geology Review |year= 2022 |volume=65 |issue=16 |pages=1–27|doi=10.1080/00206814.2022.2145512 |bibcode=2023IGRv...65.2479P }}
- *{{coord|18|00.25|N|151|13.50|E|display=inline}}
- *121 ± 2.8 to 98.5 ± 1.4 Ma
- Ioah Seamount (also known as Ioah Guyot, Ioan Seamount or Fedorov Seamount)
- *{{coord|14|06.00|N|156|08.40|E|display=inline}}{{cite web|title=Ioah Seamount|website=Seamount Catalog|url=https://earthref.org/SC/SMNT-141N-1561E/|access-date=5 Mar 2023}}
- * 87 million years old
- Pako Guyot
- *{{coord|15|42.83|N|155|11.96|E|display=inline}}{{cite web|title=Pako Guyot|website=Seamount Catalog|url=https://earthref.org/SC/SMNT-157N-1552E/|access-date=5 Mar 2023}}
- * 92 million years old but volcanics have been now dated in range 112 to 86 Ma and < 20 Ma in smaller volcanoes on the guyot.{{cite journal |first1=I.S. |last1=Peretyazhko| first2= E.A. |last2=Savina |first3= I.A. |last3=Pulyaeva |first4= D.S. |last4=Yudin |title= Intraplate Volcanism of the Alba Guyot: Geodynamic Formation Models of the Magellan Seamounts in the Pacific Ocean for 100 million years|journal=Russian Geology Geophysics | year=2023 |volume= 64 |issue=1 |pages=1–27|doi=10.2113/RGG20214422|bibcode=2023RuGG...64....1P }}
- Vlinder Guyot (also known as Alba Guyot)
- *{{coord|16|57.61|N|154|16.63|E|display=inline}}{{cite web|title=Vlinder Guyot|website=Seamount Catalog|url=https://earthref.org/SC/SMNT-169N-1543E/|access-date=5 Mar 2023}}
- * 95 million years old
- Ita Mai Tai Guyot
- *{{coord|12|51.00|N|156|46.20|E|display=inline}}{{cite web|title=Ita Mai Tai Guyot|website=Seamount Catalog|url=https://earthref.org/SC/SMNT-129N-1568E/|access-date=5 Mar 2023}}
- * 118 million years old
=Geology=
The volcanoes are part of a hotspot chain whose formation ages are in the range 121 to 86 million years ago.{{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 |pages=435–442 |doi=10.1134/s1819714016060038 |bibcode=2016RuJPG..10..435M |s2cid=132364693 |language=en |issn=1819-7140}} However recently sampling has shown secondary volcanic activity at about 20 million years ago. Pako Guyot, which is quite large, is to date the only ocean island basalt seamount where two quite distinct mantle plume components have been discovered in one seamount, being an extreme high μ = 238U/204Pb mantle (HIMU) and enriched mantle 1 (EM1) component. These are respectively suggestive of associations with the Arago hotspot and/or the Rarotonga hotspot and make a previously suggested association with the Samoa hotspot less likely.
Given their age the guyots have also had sedimentary deposits which have been characterised as reef and planktonic limestones.{{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 |language=en |issn=1819-7159}}{{cite journal |last1=Pletnev |first1=S. P. |title=The Main Types of Paleogene Sedimentary Rocks and Conditions of their Formation on the Guyots of the Magellan Seamounts (Pacific Ocean) |journal=Russian Journal of Pacific Geology |date=1 January 2021 |volume=15 |issue=1 |pages=72–83 |doi=10.1134/S1819714021010061 |bibcode=2021RuJPG..15...72P |s2cid=232042072 |url=https://link.springer.com/article/10.1134/S1819714021010061 |language=en |issn=1819-7159}} They are of interest for their mineral potential, for example with cobalt containing ferromanganese nodule deposits.