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Geomagnetism: Earth’s magnetic field
Dipole Field
Strength of Earth’s magnetic field (nT)
Higher order poles
Power spectrum of Earth’s magnetic field
Inclination of Earth’s magnetic field
Inclination of Earth’s magnetic field
Inclination and Declination
Inclination is relatedto latitude
Declination dependson horizontal components
Declination of Earth’s magnetic field
Magnetic North Pole vs. time
Magnetic vs. Geographic coordinates
Dipole driftswestward at:0.044 - 0.14°/century(2500-8000 yr period)
Non-dipole featuresdrift westward at:0.2 – 0.7°/century(550-1650 yr period)
Geomagnetic field strength is decreasing:Will fall to zero in the year 4000:The beginning of a reversal?
Paleomagnetism:Study of geomagnetic field vs. time
Spinner magnetometer
Astatic magnetometer
Cryogenicmagnetometer
Axial Geocentric Dipole Hypothesis: average over 104 yearsis geographic pole
tan I = 2 tan λ Plio-Pleistocene paleomag poles
Calculating a paleomagnetic pole
Baked contact test
Reversals Test
Apparent Polar Wander paths
Paleo Reconstructions
Magnetic Reversals
Magnetic Reversals vs. Time
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