Impact Cratering: Processes, Products and Effects

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Impact cratering is a fundamental and ubiquitous geological process in the Solar System. It is considered the most important surface process on the Moon, Mercury, asteroids, and over large parts of the more geologically active planets of Mars and Venus. There is also growing awareness that meteorite impact events have also played an important role throughout Earth's history, shaping the geological landscape, affecting the evolution of life, and producing mineral and hydrocarbon deposits of major economic significance. This research program will further our understanding of meteorite impact events and their beneficial scientific and economic effects. This is particularly important for Canada, which draws such a huge amount of wealth from the mining within the Sudbury impact structure the richest mining district in North America. The central guiding theme of the proposed research is Meteorite Impacts - Processes, Products, and Effects. The overarching goal and long-term (5+ years) objective of my research is to investigate and to quantify the potential beneficial effects of meteorite impact events on Earth, from the generation of new, unique habitats for life to the formation of mineral deposits of economic potential. To understand these beneficial effects, the short-term (years 15) Objectives of the proposed research is to investigate three key Processes involved in the formation of meteorite impact structures, namely: Objective 1) Understand how rocks are metamorphosed and melted during impact events; Objective 2) Understand how impact ejecta is emplaced; Objective 3) Understand how hydrothermal systems within impact craters develop and evolve. This work focuses on comparative study of impact craters on the Earth, Moon and Mars, with a focus on the study of craters ~240 km in diameter within different types of target rocks and in different states of preservation. This will enable the differentiation of local effects and features of specific craters from more general features of impact craters. Fieldwork forms the foundation for this research coupled with the investigation of samples with a series of cutting-edge analytical techniques. In addition to fieldwork at the Haughton, Mistastin Lake, Ries, Rochechouart, and West Clearwater Lake impact structures, this research also capitalizes on the transfer of the Impact Crater Collection of the Geological Survey of Canada, which has recently been transferred to Western. This collection comprises ~8 km of drill core from Canadian craters as well as ~8,000 hand samples and ~3,100 thin sections from craters in Canada and from around the world. Field and laboratory observations will be synthesized through this research program to develop a generic model for the modification of an impact crater, from the development of an impact hydrothermal system, followed by sedimentary infilling and/or erosion.