Strontium (Sr) isotope ratios (87Sr/86Sr) can provide insights into a range of environmental processes. Previous authors have mapped 87Sr/86Sr in both bedrock and water across large spatial scales, but these efforts have assumed that the weathering of primary minerals in bedrock is the only source of environmentally available Sr. Bataille et al. (2012) has developed a new three-source model that incorporates Sr fluxes from atmospheric aerosols, including soluble Sr produced by the weathering of deposited Saharan mineral dust and deposition of dissolved sea salt.
The authors compared observed Sr isotopic ratios from the EarthChem Portal with model output from both the bedrock-only model and the three-source mixing model in order to evaluate model accuracy within the circum-Caribbean region (Antilles and Mesoamerica). Although the authors found that bedrock weathering is the primary source of bioavailable Sr in the region (see A below), the three-source mixing model performed better at predicting observed Sr isotope ratios (see B below) across the region. The authors asserted the importance of "using process-oriented spatial modeling to improve the predictive power of Sr isoscapes over large spatial scales and to refine sampling strategies and bioavailable Sr dataset interpretations for provenance studies."
Clement P. Bataille, Jason Laffoon, and Gabriel J. Bowen (2012), Mapping multiple source effects on the strongium isotopic signatures of ecosystems from the circu,-Caribbean region, Ecosphere, 3, 12, 1-24. DOI:10.1890/ES12-00155.1