0000000000299145
AUTHOR
Nils Höche
Multi-isotopic and trace element evidence against different formation pathways for oyster microstructures
Geochimica et cosmochimica acta 308, 326-352 (2021). doi:10.1016/j.gca.2021.06.012
Late Turonian climate variability in the Bohemian Cretaceous Basin – A sclerochronological study of Inoceramus hercules shells from the Úpohlavy quarry (Czech Republic)
Abstract The δ18O record of well-preserved shells of the inoceramid Inoceramus hercules from the Upohlavy working quarry (Czech Republic) provides an insight into the climate variability in the late Turonian benthic environment of the Bohemian Cretaceous Basin. Similar to modern bivalves, this inoceramid species built its shell near equilibrium with the oxygen isotope value of the ambient water. Due to the nearly year-round shell growth, sequentially sampled δ18O values allowed to estimate the narrowest sub-annual temperatures fluctuations that prevailed during lifetime of the organisms. In accordance with previous studies, reconstructed temperatures suggest colder water conditions (19.0 ± …
Morphological variations of crossed-lamellar ultrastructures of Glycymeris bimaculata (Bivalvia) serve as a marine temperature proxy
Abstract Bivalve shells are among the most promising archives for high-resolution seawater temperature reconstructions. However, despite major research advances in bivalve sclerochronology over the past decades, estimating water temperature from shells remains a challenging task. This is largely because the most frequently used and widely accepted temperature proxy in bivalves, i.e., the shell oxygen isotope (δ18Oshell) value, also requires knowledge of changes in δ18O of the water (δ18Owater) in which the bivalve lived, which is rarely available for ancient environments. According to a few recent studies, the size and shape of individual biomineral units (BMUs) of the shell ultrastructure …