viscous remanent magnetization

geophysics

Also known as: VRM

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Last updated

July 14, 2026

Quick Summary

Viscous remanent magnetization (VRM) is a type of permanent magnetism found in rocks that results from thermal agitation. It is acquired slowly over time at low temperatures and in the Earth's magnetic field. While VRM is weak and unstable, it is present in most rocks.1

Remanent magnetism, in general, is the permanent magnetism retained by rocks, reflecting the Earth's magnetic field orientation during their formation. This phenomenon is crucial for paleomagnetic studies, such as understanding polar wandering and continental drift. Other types of remanent magnetization include thermoremanent magnetism (TRM), acquired when magnetic minerals cool through their Curie point, and detrital remanent magnetism (DRM), acquired by magnetic mineral grains settling in sedimentary environments. Geophysics utilizes the study of these magnetic properties of rocks to investigate subsurface resources and understand Earth's history.21

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Types of remanent magnetization
VRM (viscous remanent magnetization) results from thermal agitation. It is acquired slowly over time at low temperatures and in the Earth’s magnetic field. The effect is weak and unstable but is present in most rocks.
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VRM (viscous remanent magnetization) results from thermal agitation. It is acquired slowly over time at low temperatures and in the Earth’s magnetic field. The effect is weak and unstable but is present in most rocks.
Read More