Image: LIRM anomaly with archaeological hearths

Description: Lightning induced remnant magnetization (LIRM) of soil mapped with a magnetometer. The lightning-induced anomaly was detected during a magnetic survey of an archaeological site in Wyoming (USA) (see Archaeological geophysics). The LIRM anomaly was initially interpreted as a possible archaeological feature, however excavations failed to identify a plausible source of the anomaly. Subsequent analysis of soil samples from the anomaly identified a very strong isothermal remnant magnetization that had been induced during a lightning strike. Prehistoric hearth/ovens also appear in the image as small circular magnetic anomalies.
Title: LIRM anomaly with archaeological hearths
Credit: http://www.archaeophysics.com/pubs/LIRM.html
Author: Pöhönen (talk)
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License: CC-BY-SA-3.0
License Link: https://creativecommons.org/licenses/by-sa/3.0/
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