Exploring the origins of magnetization within the Chicxulub crater upper peak ring

• DOI: 10.1111/maps.14331
• Publication Date: 2025-03-12T05:25:15Z
• Authors: Christina M. Verh...; Sonia M. Tikoo; Martin Schmieder; Jérôme Gattacceca; François Demory; Juliane Gross; David A. Kring; Paul V. Burger; Sean P. S. Gulick; Joanna V. Morgan; Mario Rebolledo‐V...; Jaime Urrutia‐Fuc...; Annemarie E. Pick...; Cornelia Rasmussen

AbstractLarge terrestrial impacts may produce vast subsurface hydrothermal systems, capable of generating conditions favorable to the origin of life. Modeling suggests that these systems may persist for >1 million years for basin‐sized craters; however, direct experimental constraints on hydrothermal system duration are needed. Paleomagnetism may be used as a tool to study the nature and duration of the postimpact hydrothermal system generated within the upper peak ring of the 200 km diameter Chicxulub crater (Yucatán Peninsula, México). Previous work observed that upper peak ring suevite samples contained characteristic remanent magnetizations with negative and positive inclinations, with most samples having a magnetic inclination close to −44°, the expected paleoinclination at the crater at the time of the impact. This magnetic record was at the time interpreted as chemical remanent magnetization (CRM) acquired over a period of at least 150 thousand years, from the time of the impact in geomagnetic Chron C29r into Chron C29n. We conducted further paleomagnetic and rock magnetic studies of upper peak ring rocks and found that, while most samples likely contain CRM acquired during Chron C29r, the dispersion of magnetic inclinations within suevite subunits is more likely attributed to pre‐depositional remanence held within clasts than the recording of magnetic reversals. Therefore, the paleomagnetic record of the peak ring suevites is non‐ideal for inferring the duration of the Chicxulub postimpact hydrothermal system.