Past event

SEES Seminar: Prof. John Higgins (Princeton University) Title: The history of the global carbon cycle as recorded by the chemical composition of shallow-water marine carbonate sediments

Health guidelines for this event

  • Face masks required

Summary: Shallow-water carbonate sediments are one of the most important geologic sinks of CO2 emitted from Earth's interior and a widely used archive of Earth's chemical and climate history. Some of the main limitations in interpreting the chemistry of ancient carbonate sediments include the potential for post-depositional diagenetic alteration and uncertainties in how to relate chemical changes in shallow-water environments to the global carbon cycle. In this talk Prof. Higgins will discuss his labs efforts — using measurements of the stable isotopes of calcium, magnesium, and lithium – to disentangle the effects of diagenesis and local processes in ancient shallow-water marine carbonates in order to more accurately reconstruct the chemical composition of seawater in the geologic past. He will argue that his results are inconsistent with the commonly-used approach of using stratigraphic excursions in carbon and other geochemical proxies in shallow-water marine carbonate sediments as quantitative indicators of global isotopic mass balance.