Date of Award
Doctor of Philosophy (PhD)
Several problems in the fields of tectonics, structural geology and isotopic dating were examined and simplified using computer programs. These problems include the theory of refolding, refold applications to three mining areas, hotspots and their relationship to mantle convection systems and ionium dating of volcanic rocks. In the first study, it was shown that current refold classification schemes are inadequate and so modifications were suggested. Various other aspects of multiple generations of interfering folds were also examined. The ideas of refold theory were then applied to three mining areas, the Chisel Lake Ore Body of Manitoba, the Galena-Roubaix District of South Dakota and Montauban-les-Mines of Quebec. These three studies represent three different techniques of identifying fold generations.
The third study of this dissertation involved the examination of hotspots/highspots at various localities of the earth. The distribution was then used to define a polygonal convection system, which is similar to laboratory mantle models. It was also attempted to integrate this model with recent whole mantle convection models to see if the combination was compatible with observed hotspot tracks.
The final study involves a review of the deficiencies of the various ionium dating techniques used on volcanic rocks. A new method was presented which is free of these deficiencies
Thiessen, Richard Leigh, "Theoretical and computer assisted studies in tectonics, structural geology and isotope dating" (1980). Geology Theses and Dissertations. 111.