Mesozoic dipole low: Myth or reality?

Study of the long‐term variation of polarity and paleo‐direction of the Earth's magnetic field in the Precambrian and Phanerozoic has proved valuable in geosciences. Magnetic polarity in the Mesozoic and Cenozoic is fairly well established, with some first‐order trends defined for older times. Defining Earth's comparable long‐term dipole moment variation has proved far more difficult [e.g., Selkin and Tauxe, 2000]. Among many other findings, magnetic polarity studies have defined several first‐order features like the Permo‐Triassic and Cretaceous superchrons, characterized by constant reverse and normal polarity, respectively, over long intervals.