[ pey-lee-oh-mag-ni-tiz-uh m or, esp. British, pal-ee- ]
/ ˌpeɪ li oʊˈmæg nɪˌtɪz əm or, esp. British, ˌpæl i- /


Geology. magnetic polarization acquired by the minerals in a rock at the time the rock was deposited or solidified.

Origin of paleomagnetism

First recorded in 1850–55; paleo- + magnetism
Related formspa·le·o·mag·net·ic [pey-lee-oh-mag-net-ik or, esp. British, pal-ee-] /ˌpeɪ li oʊ mægˈnɛt ɪk or, esp. British, ˌpæl i-/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Science definitions for paleomagnetism


[ pā′lē-ō-măgnĭ-tĭz′əm ]

The fixed orientation of a rock's magnetic minerals as originally aligned at the time of the rock's formation. Paleomagnetism is usually the result of thermoremanent magnetization (magnetization that occurs in igneous rocks as they cool). Examination of the paleomagnetism of the Earth's ocean floors revolutionized the field of geology by providing evidence for the existence and movement of tectonic plates. See Note at magnetic reversal.
The scientific study of such magnetic remanence.
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