Geochemical signatures of the early Campanian belemnite Belemnellocamax mammillatus from the Kristianstad Basin in Scania, Sweden
article Macrofossil calcite plays a central role for palaeoenvironmental reconstructions because its preservation state and geochemical signatures can be checked using a variety of screening techniques. Reconstructions of the ecology and seawater composition from such data require knowledge about species-specific compositions of well-preserved calcitic fossils. Comprehensive datasets, recording averages, intraspecimen and intraspecific variability of geochemical proxies in fossil calcite, however, are still largely lacking. Here we report δ 13 C and δ 18 O values, as well as Mg/Ca, Sr/Ca and Mn/Ca ratios of 204 aliquots sampled along transectsthroughthree rostraof thelate earlyCampanianbelemnite speciesBelemnellocamax mammillatus. Geo- chemical signatures of partially altered samples are consistent to those reported for early marine calcite cemen- tationandshowtrendstowardsmoderatelyhigherMn/Ca,heavier δ 13 CandlowerSr/Ca.Incontrast,Mg/Caratios and δ 18 O values remain similar to projected original values. Median δ 18 Ov alues of−0.3 to 0.0‰ are comparable to the heaviest values of coeval oysters from the same localities, and internal variability of the well-preserved parts of the rostra is low. These findings suggest that B. mammillatus lived mostly in the deep part of the basin where seasonal changes were low and water temperatures cool. The δ 13 C is offset from oysters and most coeval