PALEOMAGNETIC TIME SCALE


MAGNETOSTRATIGRAPHY: study of changes in the earth's magnetic field

HISTORY: based on technology developed since the 1950's.
The Polarity Time Scale Commission (IUGS) first met in 1972

PRINCIPLES:
COMPONENTS (declination, inclination, strength) CHANGE THROUGH TIME
METHODS
TYPES OF PALEOMAGNETISM
TIME SCALE
PROBLEMS (particularly for 80 my chronology)
TERMINOLOGY
  1. polarity epoch (Chron) chronologic unit characterized by one geomagnetic polarity lasting 105 - 106 years
  2. polarity event chronologic unit characterized by one geomagnetic orientation: 104 - 105 years
  3. polarity excursions brief events without complete reversal
SECULAR VARIATION AND DATING ARCHEOMAGNETISM: measurement of position of Virtual Geomagnetic Pole (VGP) recorded in archeological samples
Secular Variation is the movement of the VGP through time
Archeomagnetism important in Southwestern Desert Archeology
Paleomagnetic (TRM) acquired through Study of Archeomagnetism began with 1950's study of Roman and Japanese kilns
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Archeomag Web Page

Paleomag Readings

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