Geodynamo history preserved in single silicate crystals; origins and long-term mantle control

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doi: 10.2113/gselements.5.4.217
Author(s): Tarduno, John A.
Author Affiliation(s): Primary:
University of Rochester, Department of Earth and Environmental Sciences, Rochester, NY, United States
Volume Title: Elements
Source: Elements, 5(4), p.217-222. Publisher: Mineralogical Society of America and Mineralogical Society of Great Britain and Ireland and Mineralogical Association of Canada and Geochemical Society and Clay Minerals Society, International. ISSN: 1811-5209
Note: In English. 33 refs.; illus.
Summary: The long-term history of the geodynamo provides insight into how Earth's innermost and outermost parts formed. The magnetic field is generated in the liquid-iron core as a result of convection driven by heat carried across the core-mantle boundary and freezing of the solid inner core. Earth's magnetic field acts as a shield against energetic solar radiation, and therefore the geodynamo played an important role in the development and retention of our atmosphere, ultimately setting the stage for the evolution of life. A new analytical approach, using single silicate crystals that host minute magnetic particles, can reveal heretofore hidden aspects of Earth's magnetic history. This method is being used to address some of the outstanding questions regarding the long-term behavior of the geodynamo.
Year of Publication: 2009
Research Program: ODP Ocean Drilling Program
Key Words: 18 Geophysics, Solid-Earth; Archean; Atmosphere; Chronology; Convection; Core; Core-mantle boundary; Crystals; Dipole moment; Dynamos; East Pacific Ocean Islands; Feldspar group; Framework silicates; Hadean; Hawaii; Hysteresis; Inner core; Lava flows; Leg 197; Magnetic domains; Magnetic field; Magnetization; Mantle; Multidomains; Natural remanent magnetization; Ocean Drilling Program; Oceania; Outer core; Paleomagnetism; Plagioclase; Polynesia; Precambrian; Pseudo-single domains; Remanent magnetization; Silicates; Single domains; Solar radiation; TEM data; Thermoremanent magnetization; United States; Viscous remanent magnetization
Coordinates: N340000 N520000 E1730000 E1670000
Record ID: 2009083384
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Abstract, copyright, Mineralogical Society of America, Reference includes data from GeoScienceWorld, Alexandria, VA, United States