Bivalve sclerochronology

Abstract

Bivalve sclerochronology developed from the observations of visible growth lines and increments on the outer shell layer and along cross-sectioned shells cut along the maximum axis of growth. Such growth patterns are often visible with the naked eye, but in some species these features are more clearly revealed with staining or acetate peels. Sclerochronologic records from long-lived bivalves provide master chronologies used to reconstruct climate change on decadal to centennial time scales. Records from short-lived bivalves can be resolved on seasonal time scales. In combination with geochemical proxies, sclerochronologic records can produce time series of environmental variability that can be quantified (e.g., estimating water temperature, salinity). Their abundance in fossil and archaeological deposits and their wide biogeographic distribution make bivalve shells unique and valuable archives for a wide range of interdisciplinary study.