Geomagnetic polarity epochs: A new polarity event and the age of the Brunhes-Matuyama boundary

Richard R. Doell; G. B. Dalrymple

doi:10.1126/science.152.3725.1060

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Geomagnetic polarity epochs: A new polarity event and the age of the Brunhes-Matuyama boundary

Richard R. Doell·G. B. Dalrymple

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Abstract

Recent paleomagnetic-radiometric data from six rhyolite domes in the Valles Caldera, New Mexico, indicate that the last change in polarity of the earth's magnetic field from reversed to normal (the Brunhes-Matuyama boundary) occurred at about 0.7 million years ago. A previously undiscovered geomagnetic polarity event, herein named the "Jaramillo normal event," occurred about 0.9 million years ago.

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Source-reported bounding extent: 35.82353517773839° to 35.94364196549704° latitude; -106.64619231455076° to -106.42705212925159° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Richard R. Doell, G. B. Dalrymple. 1966. Geomagnetic polarity epochs: A new polarity event and the age of the Brunhes-Matuyama boundary. https://doi.org/10.1126/science.152.3725.1060

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