High Geomagnetic Reversal Frequency During the Middle to Late Ediacaran (∼570 Ma) Constrained by Integrated Magneto‐ and Cyclostratigraphy

The Ediacaran–Cambrian (∼635–539 Ma) geomagnetic field is characterized by unusually high reversal rates and markedly weakened field strength. Estimates of these reversal frequencies can reveal key aspects of deep Earth dynamics and their potential influence on surface environments and early complex life. Here, we present a constraint on geomagnetic reversal rates at ∼570 Ma by integrating previously acquired magnetostratigraphic data and cyclostratigraphic analyses from three drill cores (E7, E34, and H9) of the Ediacaran Avellaneda Formation (La Providencia Group, Argentina). Cyclostratigraphic analysis was conducted using a grayscale series derived from sediment color, which captures compositional variability linked to marl–limestone and claystone–limestone alternations. Time‐series analyses identified a complete hierarchy of orbital cycles above the 95% confidence level, and whose period ratios closely match those expected at ∼570 Ma. The optimal sedimentation rate estimate of 0.9–2.2 cm kyr −1 supports the interpretation of Milankovitch‐driven cyclicity. Using a Gaussian bandpass filter, we isolated the 100 kyr cycle bands to construct a floating astronomical timescale for the Avellaneda Formation. Cyclostratigraphic calibration yields estimated durations of 850 ± 56 kyr (core E7), 900 ± 37 kyr (core E34), and 1,000 ± 85 kyr (core H9), which imply constrained reversal frequencies of approximately 7–11reversals per million years. Our results confirm the hyperactive geomagnetic reversal regime during the late Ediacaran. Moreover, these findings contribute to understanding the evolution of the geodynamo and its broader implications for the co‐evolution of Earth's interior, atmosphere, and biosphere during a critical interval of Earth's history.