I integrate sedimentology, stratigraphy, and isotope geochemistry to reconstruct ancient environments within the context of secular and progressive tectonic, biospheric, and climatic evolution of the earth. The underlying theme of my research is paleoenvironmental change spanning from the late Proterozoic to the early Phanerozoic (~ 1200 to 500 ma). My goal is to document and understand the interconnections between tectonics, chemistry and oxidation state of seawater, severe climatic fluctuations (including snowball Earth), and the diversification of eukaryotes. This research is fundamentally field-based and centered on detailed geological studies of sedimentary basins that archive clues to how the Earth evolved during this time. Recent field areas include northwestern Canada, Svalbard, Saudi Arabia, Namibia, and Australia. The geochemical techniques my students, colleagues, and I employ to interrogate the sedimentary rock record include both trace element geochemistry, traditional isotopic systems (C, O, S, N, Sr) and non-traditional isotopes (e.g. Fe, Zn, Cu, and Hg).