Speaker: Madeleine S. Bohlin, Researcher at the Department of Earth Sciences, Uppsala University

Abstract
weathering, this work explores variations in the Li isotopic composition of river waters and sediments in catchments in the Himalayan mountains, forming the headwaters of the Ganges. In such mountainous ‘kinetically limited’ weathering environments, chemical weathering occurs along a range of groundwater flow paths in fractured saprolite and rock. In this presentation, I will introduce a simple 1-dimensional reactive transport model which describes the evolution of the Li isotopic composition along such flow paths. Results from the modelling put constraints on silicate dissolution rates, secondary mineral formation, reaction stoichiometry and fluid fluxes within catchments. The comparison of these parameters between catchments which vary in size, altitude, lithology, annual rainfall and uplift rates provide a nuanced view of the controls on Li isotope fractionation, and by extension, the controls on silicate weathering.

Relevant paper: https://www.sciencedirect.com/science/article/abs/pii/S0012821X19300603?via%3Dihub

Madeleine Bohlin CV (155 Kb)