The PROPS Group (...see Alumni here)

Professor Galen Halverson

firefoxI 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 to reconstruct paleoenvironmental change spanning from the late Proterozoic to the early Phanerozoic (~ 1200 to 500 ma) and to understand the interconnections between tectonics (i.e., supercontinental break-up and assembly), seawater chemistry and ocean redox, severe climatic fluctuations (including snowball Earth), and the origin and diversification of animals. This research is fundamentally field-based and geared around detailed geological studies of sedimentary basins that formed during this time.

Dr. Thi Hao Bui

Research Associate and Stable Isotope Lab Deity

firefoxGas hydrates attract broad scientific interest because of their important role in the global carbon cycle and their potential as an energy resource and geological hazard. Because the majority of global gas hydrate reservoirs have formed in marine sediments, especially in convergent margins, different geophysical and geochemical techniques have been developing to identify gas hydrate distribution and abundance in marine sediments. Among those, pore water sulfate profiles appear to be a simple tool to estimate the methane fluxes and gas hydrate saturation contents. It is clear in a broad sense that systems dominated by methane migrating from deep sources with higher methane fluxes will be characterized by shallow sulfate methane transition (SMT) depths and high average gas hydrate saturation states. However, SMT depths are not only controlled by the underlying methane flux, but they also depend on the availability of sulfate from the overlying sediment column. It is therefore important to understand the integrated microbial processes controlling sulfur cycling in the system.

 

Timothy Gibson

PhD student

My research utilizes various late Mesoproterozoic to early Neoproterozoic (ca. 1200–800 Ma) sedimentary successions in arctic Canada as natural laboratories to investigate connections between Earth’s tectonic, geochemical, and biological histories. This work begins out in the field, where a robust depositional framework is constructed by integrating mapping, sedimentology, and sequence stratigraphy, and is highly collaborative in nature – I work with other field geologists and geochemists, as well as paleontologists and biologists. Because timing, correlation, and rates of change are essential for deciphering these ancient stories, I implement U-Pb and Re-Os geochronology wherever possible to obtain absolute ages. I also analyze various radiogenic isotopes (Sr, Nd, Os) in these ancient strata to characterize the influence of chemical weathering on basin water chemistry to elucidate how tectonics affect Earth’s biological and geochemical evolution through silicate weathering and the supply of nutrients to the ocean. Ultimately, these data will help characterize the tectonic evolution of northern Laurentia, as well as the roles various global tectonic regimes throughout Rodinia’s lifespan played leading up to perturbations to the carbon cycle later in the Neoproterozoic Era.

Sarah Worndle

PhD student

firefoxEarth's redox system has evolved over Earth's history, but quantifying this change in the Precambrian is challenging. My research focuses on global changes to Earth's environment across the Mesoproterozoic-Neoproterozoic transition. The goal of my PhD project is develop new and better calibrated records of redox and seawater chemistry spanning this transition and to relate these changes to eukaryotic evolution, the assembly of Rodinia, and other first-order geological events.

 

 

Kelsey Lamothe

MSc student, Earth and Planetary Sciences

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Pascale Daoust

PhD student, Earth and Planetary Sciences

firefoxCarbonate rocks and sediments are an important component of the Earth system, in particular in the context of ocean acidification. Therefore, ancient and modern carbonates can provide insights on both the effects of modern climate change and past paleoclimatic perturbations. The objective of my PhD research is to simulate the progressive impact of ocean acidification on the mineralogy of modern platform carbonate sediments and compare the results with the mineralogy of ancient carbonates from key greenhouse periods in Earth's history.

Wilder Greenman

PhD student, Earth and Planetary Sciences

firefoxI’m investigate the ecological niches where the first complex organisms on Earth would have evolved during the Proterozoic. This detailed work requires a combination of sedimentology, micropalaeontology and isotope geochemistry to reconstruct  these ancient environments. To understand the evolution of the basins where these events took place, I employ tools such as sequence stratigraphy, chemostratigraphy, and geochronology. Fieldwork for my PhD project will take place mainly on the late Mesoproterozoic Bylot basins of Baffin Island. I aim to answer questions about the interplay between the evolution of complex microorganisms, climatic shifts and biogeochemical change.

PROPS Alumni