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Magnetic reversals and mass extinctions.

¹Department of the Geophysical Sciences, University of Chicago, Illinois 60637, USA.

|March 28, 1985

Summary

Earth's magnetic field reversals show a consistent 30 million year cycle. This geological timescale periodicity predicts future pulses of increased magnetic field activity, potentially linked to biological extinction events.

Area of Science:

Geophysics
Paleomagnetism
Earth Science

Background:

Analysis of Earth's magnetic field reversal timing has produced conflicting results regarding periodicity.
Some studies suggest a 10 million year periodicity, while others find random spacing.
Potential links between magnetic field reversals and biological extinction events warrant further investigation.

Purpose of the Study:

To analyze the time distribution of Earth's magnetic field reversals over the past 165 million years.
To identify any significant periodicities in the magnetic reversal record.
To assess the implications of identified periodicities for understanding Earth's dynamic processes and their potential impact.

Main Methods:

Time series analysis of paleomagnetic data.

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Statistical examination of the Earth's magnetic reversal record spanning 165 million years.

Identification and characterization of periodic signals within the reversal data.

Main Results:

A stationary periodicity of 30 million years was identified in the magnetic reversal record.
This 30 million year cycle is superimposed on previously established non-stationarities.
The study predicts pulses of increased magnetic reversal activity at specific intervals (10, 40, 70 million years Before Present).

Conclusions:

The Earth's magnetic field reversal process exhibits a significant 30 million year periodicity.
This periodicity provides a predictive framework for future reversal activity.
The findings contribute to understanding long-term geodynamo behavior and its potential correlation with major Earth events.