Proxy Primers

SGP Proxy Primer: Thallium isotopes

This Proxy Primer is presented by Dr. Chad Ostrander (University of Utah) and provides an accessible introduction to thallium isotopes in carbonates and shales. This proxy is a sensitive recorder of ancient bottom water oxygen levels and can inform us about ventilation of the deep ocean.

SGP Proxy Primer: Paleosalinity

This Proxy Primer is presented by Dr. Thomas Algeo (University of Cincinnati) and provides an accessible introduction to paleosalinity proxies and reconstructions. These proxies are providing surprising new insights on basins previously considered fully marine and showing how redox, primary productivity, and ancient marine life varied with changes in salinity.

SGP Proxy Primer: Bayesian approaches to stratigraphy

This Proxy Primer is presented by Tianran Zhang (Dartmouth College), Dr. Martin Smith (Durham University), and Dr. Kilian Eichenseer (Durham University) and provides an accessible introduction to Bayesian approaches in subsidence analysis and stratigraphic correlation The primer uses examples from Tonian (Neoproterozoic) record of Svalbard and dating the first appearance of trilobite fossils.

SGP Proxy Primer: Strontium isotopes

This Proxy Primer is presented by Dr. Graham Shields (University College London) and Dr. Ying Zhou (Johannes Gutenberg University Mainz) and provides an accessible introduction to strontium isotope stratigraphy. The primer explains what determines the 87Sr/86Sr ratio of geological materials and seawater, how signals are preserved (and altered), a new sequential leaching protocol to obtain the most reliable seawater data, strontium isotopes as stratigraphic tools and weathering proxies, and case studies as applied to Earth history.

SGP Proxy Primer: Uranium Isotopes

This Proxy Primer is presented by Dr. Kim Lau (Penn State) and provides an accessible introduction to the uranium isotope redox proxy in carbonates and shales. The primer explains how the measurements are made, the global uranium budget and fractionations into different sinks, and case studies as applied to Earth history.

SGP Proxy Primer: Cerium Anomalies and other Rare Earth Elements

This Proxy Primer is presented by Dr. Rosalie Tostevin (University of Cape Town) and provides an accessible introduction to analyzing cerium anomalies and other Rare Earth Elements as a redox proxy in carbonates. The primer uses examples from the Ediacaran Nama Group of Namibia and South Africa and as well as Archean Banded Iron Formations.

SGP Proxy Primer: Programmed Pyrolysis and Rock Eval

This Proxy Primer is presented by Dr. Alex Zumberge (GeoMark) and provides an accessible introduction to programmed pyrolysis (commonly referred to by the commercial name 'Rock Eval'). The primer explains the history of the technique, how the measurements are made, and how geologists can use programmed pyrolysis to screen samples for more complicated future work such as biomarker analysis.

SGP Proxy Primer: Analyzing Large Geochemical Datasets

This Proxy Primer is presented by Dr. Akshay Mehra (University of Washington) and Dr. Kurt Sundell (Idaho State University) and provides an accessible introduction to analyzing large geochemical datasets--in particular accounting for spatial biases in the data. The primer uses examples from sedimentary uranium contents, ooid sizes, and the record of hafnium and oxygen isotopes in zircon.

This Proxy Primer is presented by Dr. Selva Marroquin (Caltech) and provides an accessible introduction to organic and inorganic carbon isotopes and carbon isotope chemostratigraphy.

This Proxy Primer is presented by Dr. Zunli Lu (Syracuse University) and presents an accessible introduction to the Iodine/Calcium (I/Ca) redox proxy.

This Proxy Primer is presented by Dr. Eva Stüeken (University of St. Andrews) and provides an accessible introduction to the use of nitrogen isotopes in the rock record.