Advances in mollusc sclerochronology and sclerochemistry: tools for understanding climate and environment.

This Special Issue of Geo-Marine Letters compiles papers on marine, estuarine and freshwater mollusc shells as recorders of environmental and climatic conditions. Considering that many past studies have differentiated geochemical investigations from sclerochronological investigations, we propose that the sub-discipline term “sclerochemistry” be used when geochemical investigations are undertaken. This issue starts with two review papers that discuss the importance of physiology or vital effects on both sclerochronology and sclerochemistry. Several sclerochemical calibration studies on modern specimens of both bivalves and gastropods are presented (including δ¹⁸O, Mg/Ca, Sr/Ca and Ba/Ca), which illustrate the usefulness and difficulties associated with using these proxies. Studies on fossil mollusc shells are also provided, with one study that uses Pliocene scallop shells to understand past ocean circulation and another that addresses the problem of diagenesis. Finally, a sclerochronological study of crystal prism width across the shell is presented. This Special Issue demonstrates that many elemental and isotopic proxies contained in mollusc shells are complex. In spite of these complexities, environmental and climatic conditions can be extracted for use in palaeoclimatic and palaeoenvironmental research. [ABSTRACT FROM AUTHOR]