Bromine speciation as a new paleoenvironmental proxy

In paleoenvironmental archives such as peat and lake sediments, bromine (Br) generally show some correlation with organic matter (OM), but the relationship between Br and OM is not linear. The Br/OM ratio has been proposed as a proxy of the origin of historical primary productivity (macrophytes vs planktonic). We hypothesize that Br speciation could be a finer paleoenvironmental proxy. To test this hypothesis, a better understanding the cycling of Br in sediments and of chemical changes occurring during burial and sediment diagenesis are needed. This proposal is a continuation of exp EV373. We wish to complement our dataset of Br K-edge bulk HERFD-XANES spectra, with sediments at low Br content, and sources compartment.