PPT-Introduction to Stable Isotope Geochemistry

Lecture 30 Beginnings Stable isotope geochemistry is concerned with variations in the isotopic compositions of elements arising small differences in the chemical behavior of different isotopes of an . pe Geochemistry Theory. Lecture 34 . Beginnings. Stable isotope geochemistry is concerned with variations in the isotopic compositions of elements arising . small . differences in the chemical behavior of different isotopes of an . Chapter 6. Isotope Geochemistry. In isotope geochemistry, our primary interest is not in dating, but using the time-dependent nature of isotope ratios to make inferences about the nature of reservoirs in the Earth and their evolution.. A Brave New World?. Graham R Carr. CSIRO Exploration and Mining. June 2013. Outline. Traditional Use of Pb Isotopes in Metallogenic Studies. Exploration Geochemistry – . General Principles. Gossans and Residual Soils. Geochemistry?. Geo (geology, . gaia. ) + chemistry. A field of study dealing geological phenomena and problems with chemical tools and principles. Prerequisites?. Physical geology, . minerlaogy. , petrology, economic geology. Lecture 31 . Mass Dependent Fractionation. . If . a 4‰ fractionation of . δ. 18. O . is observed in a particular sample, what value of . δ. 17. O . do we predict? . We might guess it would ½ as much. . Stable isotopes are used in CCS to look for leakage of CO2 into overlying aquifers or into the surface environment. What are Stable Isotopes. These are isotope that do not decay over time as the radiogenic isotope do.. Lecture 32 . The Antarctic Ice Record. Much subsequent . paleoclimate. effort has focused on . δD. in ice cores from Antarctica and Greenland.. The . Vostok. core from Antarctica went back 400 . ka. Tracing water sources and greenhouse gases using field-based stable isotope techniques. Overview:. 2. Oxygen and Hydrogen isotopes in water. Tracing the hydrological cycle. Agricultural water use. 3. Carbon isotopes in Carbon Dioxide and Methane . Lecture 33 . Stable Isotopes in the Hydrosphere and Biosphere. Isotopic Fractionation in the Hydrosphere. δ. 18. O in the oceans is nearly constant at 0. However, as a consequence of Rayleigh fractionation and temperature dependence of the water-vapor fractionation factor, the isotopic composition of precipitation varies widely.. FIGURE 01: Simple Bohr-type model of a lithium atom. Radioactive Isotopes. Unstable isotopes decay to other nuclides. The rate of decay is constant, and not affected by P, T, X…. Parent. nuclide = . COMMON plumeswere initially thought to consist of primitive mantle (e.g., Schilling, 1973). As we found, mixing be-tween primitive and depleted mantle can explain the Sr and Nd isotopic compositions 286S Montani and Y MishimaIn this study we collected Nuta in situ by gentle means Nuta trap The purpose of thisinvestigation was to follow the Nuta decomposition and to evaluate the contribution of Nu Prosper Zigah. Woods Hole Oceanographic Institution. pzigah@whoi.edu. 1. What are Isotopes. Why care about stable isotopes?. Expressing Isotopic abundances. Isotope effects. Isotopic-mass balance calculations (two-component and multiple-component mixing models). Lecture . 29. Isochrons. This equation has the form . y = a + bx. .. Plotting the radiogenic isotope ratio against the parent daughter ratio, the intercept with be . R. 0. . and the slope will be . e.