Maree McGregor

Postdoctoral Fellow

PhD

Earth Sciences

Forestry/Geology

Fredericton

maree.mcgregor@unb.ca



Research

My research interests centers on understanding the role that hypervelocity impact events play here on Earth and throughout the inner Solar System. This involves the use of various geologic, petrologic, and analytical tools to understand the effects of extreme pressures and temperatures on terrestrial and extra-terrestrial materials. Specifically, my research focuses on the development of chronological methods that enable absolute dating of impact events throughout geologic time.

Applications of this research include understanding the history of and processes involved in solar system formation, the role of impact cratering on the geological and biological evolution of Earth, and the effects of extreme pressures and temperatures on crystallographic, geochemical and geochronological systems.

Research gate

Current projects

  • Provenance studies on impact ejecta deposits using petrology, geochemistry and geochronology.
  • Method development and in-situ application of Beta decay systems using tandem LCP-MS (Beta decay chronometry).
  • Micro-analysis and geochronology of lunar materials.

Past projects

  • Development of in-situ LA-ICP-MS phosphate U-Pb dating methodologies to obtain precise and accurate ages for terrestrial impact structures in Canada.
  • Microstructuralassessment of accessory mineral phases (apatite, titanite, zircon) from terrestrial impact structures to establish P-T-t conditions in select materials.

UNB affiliations

Collaborations

My research actively involves and continues to seek collaborations with national and international researchers. 

Selected publications

McGregor, M., Erickson, T.M., Spray, J.G., Whitehouse, M.J., (2021) High resolution EBSD and SIMS U-Pb geochronology of zircon, titanite, and apatite: Insights from the Lac La Moinerie impact structure, Canada (Contrib. Min. Petrol).

McGregor, M., McFarlane, C.R.M., Spray, J.G., (2021) U-Pb geochronology of apatite crystallized within a terrestrial impact melt sheet: Manicouagan as a geochronometer test site. Geol. Soc. Am, Special Paper 550.

McGregor, M., Dence, M.R., McFarlane, C.R.M., Spray, J.G., (2020) U-Pb geochronology of apatite and zircon from the Brent impact structure, Canada: A Late Ordovician Sandbian-Katian boundary event associated with L-chondrite parent body disruption. Contrib. Mineral. Petrol. 173:63.

McGregor, M., Walton, E.L., McFarlane, C.R.M., Spray, J.G., (2020) Multiphase U-Pb geochronology of sintered breccias from the Steen River impact structure, Canada: Mixed target considerations for a Jurassic-Cretaceous boundary event. Geochim Cosmochim Acta. 274:136 – 156.

McGregor, M., McFarlane, C.R.M., Spray, J.G., (2019) Multiphase U-Pb geochronology and shock analysis of apatite, titanite, and zircon from the Lac La Moinerie impact structure, Canada. Contrib. Mineral. Petrol. 174: 62.

McGregor, M., McFarlane, C.R.M., Spray, J.G., (2018) In situ LA-ICP-MS apatite and zircon U–Pb geochronology of the Nicholson Lake impact structure, Canada: Shock and related thermal effects. Earth Planet. Sci. Lett. 504: 185–197.