Nils Schorndorf and coworkers have published an updated Holocene sea-level record for Yucatan, Mexico. Hells Bells, underwater secondary carbonates discovered in sinkholes (cenotes) southeast of Cancun, grow in the pelagic redoxcline and reach lengths of up to 4 meters. The geochemical and stable isotope composition as well as the initial (234U/238U) activity of specimens from cenotes El Zapote, Maravilla and Tortugas, yield a growth and environmental record of ~ 8000 years. The temporal geochemical evolution of Hells Bells calcites appears to be closely linked to sea-level rise and reflects desalinization of the aquifer. Excess 234U from the previously unsaturated bedrock traces the Holocene relative sea-level rise stunningly well. Consequently, our new findings improve sea-level reconstruction by a factor of two, when compared to previously published work for the period between 8 and 4 ky BP. For more information, you can find the research article here