Living Reference Work Entry

Encyclopedia of Scientific Dating Methods

pp 1-14

Date: Latest Version

Continental Drift (Paleomagnetism)

  • Trond H. TorsvikAffiliated withCentre for Earth Evolution and Dynamics (CEED), University of Oslo Email author 
  • , Pavel V. Doubrovine
  • , Mathew Domeier

Definition

Paleomagnetism is the study of the Earth’s ancient magnetic field through the record of remanent magnetism preserved in rocks. The directions of remanent magnetization are used to deduce the position of the Earth’s magnetic pole relative to the study location at the time when this magnetization was acquired. By studying magnetizations of varying age from a single lithospheric plate, one can construct a path of apparent polar wandering (APWP) that tracks the motion of that plate relative to the geographic pole. A well-defined APWP can serve as a geochronological tool, i.e., for dating magnetizations of unknown age through a comparison of their directions with those expected from the reference APWP. Paleomagnetism can be used to date any geologic event that engenders the acquisition of remanent magnetization, including formation of igneous and sedimentary rocks, deposition of ore minerals, episodes of deformation, and other remagnetization processes.

Introduction

The development ...

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