By reading the isotopic composition of a sample—be it solid, liquid, or gaseous—one can tell a story about its origin and history. For example, if the sample is a mineral, one can elucidate the mechanisms or environmental controls involved in its formation or transformation. If the sample is an organism, one can elucidate its activity or eating habits. This course will teach you why this works, where it is applicable, and how it is done in practice.
Specifically, you will learn the theoretical principles behind equilibrium and kinetic stable isotope fractionation, understand the principles behind techniques used to analyze stable isotope composition of materials, become acquainted with a broad range of applications of stable isotopes in Earth sciences, and develop practical skills in processing and quantitatively interpreting stable isotope data.
Additionally, you will learn how to use certain data processing programs, and develop your writing, analytical, evaluation and communication skills.
Content
First, theoretical principles will be explained for equilibrium vs. kinetic isotope fractionation, mass-dependent vs. mass-independent isotope fractionation, and the temperature dependency of each. Subsequently, the following applications will be discussed in detail:
atmospheric carbon cycle, role of natural (assimilation vs. mineralization) and anthropogenic activity. Tracers: 13C in CO2, 13C and D in CH4.
hydrological cycle, and its link to paleo-thermometry. Tracers: 18O and D in H2O, clumped isotopes (13C and 18O) in carbonate minerals.
understanding the mechanisms of mineral formation and transformation from their isotopic composition (natural or experimentally perturbed);
role of biological activity (assimilation vs. mineralization pathways) on fractionation factors, tracing sources of biogenic minerals and conditions of their formation. Tracers: 13C in carbonates.
reconstruction of food-webs. Tracers: 13C and 15N in specific compounds (e.g., lipids or fatty acids).
quantification of organism-specific (e.g., microbial) rates of activity, stable isotope probing. Tracers: 13C, 15N, 18O, D
