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Full-Text Articles in Geology
Impact-Generated Dykes And Shocked Carbonates From The Tunnunik And Haughton Impact Structures, Canadian High Arctic, Jennifer D. Newman
Impact-Generated Dykes And Shocked Carbonates From The Tunnunik And Haughton Impact Structures, Canadian High Arctic, Jennifer D. Newman
Electronic Thesis and Dissertation Repository
The Canadian High Arctic contains two impact structures created by hypervelocity impact events in carbonate-rich target rocks. The remote locations of the Tunnunik and Haughton impact structures means that there are aspects of these impact structures which have yet to be fully investigated. This study characterizes the range of impact-generated dykes exposed from both impact structures which include lithic breccias, impact melt-bearing breccias, and impact melt rocks. Breccias may include silicate impact glass fragments and evidence for carbonate melt. Impact melt rocks from the Haughton impact structure contain the rare terrestrial mineral moissanite. This is only the third reported occurrence …
Characterization Of Impact Melt Rocks And Hydrothermal Mineralization At The Haughton Impact Structure, Devon Island, Canada: An Investigation Of Impacts Into Carbonate Targets, Cassandra L. Marion
Characterization Of Impact Melt Rocks And Hydrothermal Mineralization At The Haughton Impact Structure, Devon Island, Canada: An Investigation Of Impacts Into Carbonate Targets, Cassandra L. Marion
Electronic Thesis and Dissertation Repository
Impact cratering is a fundamental and ubiquitous geological process on all solid planetary bodies in our solar system. Impacts into carbonate-rich sedimentary target rocks on Earth are still poorly understood. The fate of carbonates during impact, in particular whether they undergo melting or decomposition, is actively debated. The dominant process is significant as decomposition would cause severe climatic effects due to release of large amounts of carbon dioxide into the atmosphere. At the root of the problem is the difficulty to distinguish and characterize the genesis of the variety of impactite carbonates produced. The Haughton impact structure in the Canadian …
Origins Of Stable Isotopic Variations In Late Pleistocene Horse Enamel And Bone From Alberta, Nicolle S. Bellissimo
Origins Of Stable Isotopic Variations In Late Pleistocene Horse Enamel And Bone From Alberta, Nicolle S. Bellissimo
Electronic Thesis and Dissertation Repository
Oxygen and carbon isotopic measurements of coevally formed bone and tooth enamel bioapatite from a modern equid show that these tissues record drinking water and diet isotopic signals in an identical fashion. Hence, data for both tissues can be combined to track movement, dietary changes, and seasonal variability over the animal’s lifetime, and climatic variability over longer time periods. This tool was tested for horses using ten paired tooth and bone samples to reconstruct conditions in Alberta during the Late Pleistocene. While post-mortem isotopic alteration confounded interpretation of the results, two key findings emerged: (i) pre- and post-Last Glacial Maximum …