Formation and evolution of terrestrial hypervelocity impact structures

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A hypervelocity impact event occurs when an asteroid or comet strikes the Earth's surface, producing a shock wave that excavates a crater and generates new rocks, called impactites. These violent events have played a crucial role in the evolution of our geosphere and biosphere, and are associated with economic mineral, and hydrocarbon deposits. There are currently 190 confirmed impact craters worldwide, representing only a fraction of the total number anticipated in the geological record. My research program will address major research priorities identified by the impact community. These priorities include understanding the behaviour of sedimentary rocks in the impact environment, improving identification and confirmation criteria for impact craters formed in a variety of rock types, and constraining the timing of impact events. A series of short-term objectives integrating detailed petrographical and geochemical analysis of impactites, with experimental data, aided by computer modeling, will be undertaken to achieve identified research priorities. This program will focus on confirmed and possible impact structures in Canada's Alberta Basin. This sequence of sedimentary rocks has been extensively investigated for natural resources, but the potential of the Basin as host to a record of cratering events extending to the Paleozoic, has yet to be fully explored. One crater in the Alberta Basin the 25-km diameter Steen River impact structure is a world-class example of a complex crater with a central uplift. Combining results for the timing and paleogeographic location of Steen River, with conditions of breccia emplacement, cooling history, and evolution of its post-impact hydrothermal system, will be used to develop a complete picture of this understudied impact crater. A number of impact craters worldwide will be included in this program, to inform, and be informed by, our detailed characterization of impactites from the Alberta Basin. Successful achievement of these research objectives will improve the statistical database of impact events on Earth, and provide detailed investigation of new or understudied terrestrial impact craters formed in sedimentary target rocks. With the proposed research program, I will mentor one PhD, three MSc, and six undergraduate students, providing them with valuable advanced analytical equipment training. My training plan will enable HQP to become independently proficient using optical and electron microscopy, which are routinely used in the broad field of mineralogy and petrology. Additionally, HQP will gain expertise in image analysis techniques, thermal modelling, experiment design and execution, well logging, management skills, and become well-versed in the stratigraphy of an economically important basin. This training plan will prepare students for leadership roles in academia, industry, and government.