Fig. 6

Profiles of geochemical, microstructural, and optical signals in the studied brachiopod. These panels compare the δ13C and δ18O values, minor element concentrations, mean CL intensity (MCLI), altered fiber ratio (AFR), and altered fiber and puncta-filling cement ratio (AF-PCR) between the modern (OTTCo and SGLR) and fossil (MNTCo1–MNTCo5 and MNLR1–MNLR5) shells. a Terebratalia coreanica shells. b Laqueus rubellus shells. The geochemical profiles of each sample were fitted to the average length of interval 2 (7.74 mm for T. coreanica and 5.27 mm for L. rubellus)