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Title: Barium Isotopes: Drivers, Dependencies, and Distributions through Space and Time
In the modern marine environment, barium isotope (δ138Ba) variations are primarily driven by barite cycling – barite incorporates “light” Ba isotopes from solution, rendering the residual Ba reservoir enriched in “heavy” Ba isotopes by a complementary amount. Since the processes of barite precipitation and dissolution are vertically segregated and spatially heterogeneous, barite cycling drives systematic variations in the barium isotope composition of seawater and sediments. This Element examines these variations; evaluates their global, regional, local, and geological controls; and, explores how δ138Ba can be exploited to constrain the origin of enigmatic sedimentary sulfates and to study marine biogeochemistry over Earth’s history.  more » « less
Award ID(s):
2023456 1827401 1736949 1829546
Author(s) / Creator(s):
Lyons, Timothy W; Turchyn, Alexandra; Reinhard, Chris
Date Published:
Journal Name:
Elements in geochemical tracers in earth system science
Medium: X
Sponsoring Org:
National Science Foundation
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