Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Determining Temperatures Of Deformation In Mylonites From The Scandinavian Caledonides, With Implications For The Thermal And Kinematic Evolution Of Orogens, Andrea Marilina Wolfowicz Dec 2012

Determining Temperatures Of Deformation In Mylonites From The Scandinavian Caledonides, With Implications For The Thermal And Kinematic Evolution Of Orogens, Andrea Marilina Wolfowicz

Boise State University Theses and Dissertations

The Titanium-in-quartz (TitaniQ) thermobarometer was evaluated in ductilely sheared rocks (mylonites) from the Scandinavian Caledonides in comparison with several other thermometric methods, including: (1) TitaniQ thermometry in cross-cutting quartz veins, (2) garnet-biotite Fe-Mg exchange thermometry, (3) metamorphic phase equilibria, and (4) quartz microstructures as calibrated experimentally and empirically. In all instances, quartz vein temperatures mimic TitaniQ temperatures of the host rocks. Similarly, TitaniQ temperatures of dynamically recrystallized quartz, ranging from ~210°C at the thrust front to 475°C at the deepest structural levels, reflect the best estimate of the final temperature of deformation. Higher temperatures are also preserved locally and more …


Hillslope Asymmetry Maps Reveal Widespread, Multi-Scale Organization, Michael John Poulos May 2012

Hillslope Asymmetry Maps Reveal Widespread, Multi-Scale Organization, Michael John Poulos

Boise State University Theses and Dissertations

Hillslope asymmetry is the condition in which oppositely-facing hillslopes within an area have differing average slope angles, and indicates aspect-related variability in hillslope evolution. As such, the presence, orientation, and magnitude of asymmetry may be a useful diagnostic for understanding process dominance. We present a new method for quantifying and mapping the spatial distribution of hillslope asymmetry across large areas. Resulting maps for the American Cordillera of the Western Hemisphere and the western United States reveal that hillslope asymmetry is widespread, with distinct trends at continental to drainage scales. Spatial patterns of asymmetry correlate with latitude along the American Cordillera, …


A 14,000-Year Record Of Wildfire And Alluvial Fan Deposition Reveals Relationships Among Fire, Climate, Vegetation, And Sediment Yields In The Middle Fork Salmon River, Idaho, Kerry Elizabeth Riley May 2012

A 14,000-Year Record Of Wildfire And Alluvial Fan Deposition Reveals Relationships Among Fire, Climate, Vegetation, And Sediment Yields In The Middle Fork Salmon River, Idaho, Kerry Elizabeth Riley

Boise State University Theses and Dissertations

Changes in climate influence vegetation distributions and the frequency and severity of fire and post-fire erosion. While the frequency of large fires has increased on all vegetated continents over the last decade, it remains unclear whether recent large fires are extraordinary over millennial timescales. In the Middle Fork Salmon River of central Idaho, over 40% of the watershed has burned in the last 30 years and the subsequent increase in erosion from severely burned hillslopes has produced many large fire-related debris flows. Fires have burned throughout the steep topographic gradient of the watershed that encompasses high elevation sub-alpine and mixed …