Earth, Planets and Space

, Volume 57, Issue 5, pp 465–470 | Cite as

Geomagnetic paleointensity over 1.2 Ma from deep-tow vector magnetic data across the East Pacific Rise

  • Michiko YamamotoEmail author
  • Nobukazu Seama
  • Nobuhiro Isezaki
Open Access


Deep-tow vector magnetic data have been acquired across the fast-spreading southern East Pacific Rise 18°S and inverted to magnetization intensity variations. Vector magnetic data are used to determine continuous magnetic intensity within intervals of constant polarity over the Matuyama and Brunhes periods up to the Cobb Mountain event at 1.19 Ma. A comparison of our deep-tow vector data and a sediment core-derived geomagnetic paleointensity timescale suggests that the short-wavelength magnetic anomaly signal is indeed of geomagnetic origin and can be used to date the seafloor with a high resolution. The crustal age determined from our date reveals a highly asymmetric spreading rate for the recent period (since 0.3 Ma).

Key words

Paleointensity variation vector magnetic anomaly data deep-tow survey East Pacific Rise 


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Copyright information

© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2005

Authors and Affiliations

  • Michiko Yamamoto
    • 1
    Email author
  • Nobukazu Seama
    • 2
  • Nobuhiro Isezaki
    • 3
  1. 1.Earth and Atmospheric SciencesCornell UniversityIthacaUSA
  2. 2.Research Center for Inland SeasKobe UniversityKobeJapan
  3. 3.Department of Earth ScienceChiba UniversityChibaJapan

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