Summary Unraveling the long-term behavior of the geomagnetic field is crucial for understanding the dynamics of the deep Earth. Yet, obtaining an accurate measure of geomagnetic paleosecular variations (PSV) is difficult, partly because of tectonically induced rotations that overprint the original paleomagnetic signal. We present a detailed paleomagnetic investigation based on 99 sampling sites collected from the 119 to 112.6 Ma Ramon Volcanics exposed near the dormant Ramon Fault, southern Israel. These volcanic rocks were emplaced at equatorial paleolatitudes during the beginning of the Cretaceous Normal Superchron (CNS; 123.4-83.6 Ma), during which there were no polarity reversals. Structurally corrected remanence directions consistently vary across the investigated area, whereby the sites found near a sharp bend of the Ramon Fault are clockwise rotated, whereas the other sites show no obvious rotational pattern. Elasto-plastic modeling suggests that the rotations were induced by up to 1.5 km of dextral horizontal slip accommodated by the fault, consistent with previous geological and geophysical estimations. Considering the remanence directions obtained from sites that were not influenced by the fault, we calculated an SB value of $13.3_{ - 1.3}^{ + {{1.9}}^o}$ (95% confidence, 46 sites), which corresponds to previous SB estimations from pre- and Early CNS volcanic bodies emplaced at low paleolatitudes (λ<20˚). This observation suggests that the emergence of the superchron was not accompanied by a change in the behavior of the geomagnetic PSV. Finally, our results, together with previous paleo-equatorial observations, show that the middle part of the superchron had lower angular dispersion (i.e., lower SB) compared to the scatter that prevailed during the beginning of the superchron. This observation suggests that the geomagnetic field transitioned into a more axial dipole dominance state toward the middle part of the superchron. Altogether, our analysis indicates that the superchron cannot be treated as a period characterized by a steady-state field behavior.
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