Identification, Mapping, Analysis, and Dating of Composite Mega Landslides in the Colorado Plateau

<p>"This research consists of three articles focusing on landslide complexes within the Grand Canyon region of the Colorado Plateau. This is a vast and remote region of rugged topography. The landslide complexes in this study are greater than 10 million cubic meters in volume. The slides are located within different areas of the region and consist of differing geology but share multiple commonalities. Stratigraphic and structural controls tend to dictate where the slides occur. All of the landslides occur where carbonates and/or sandstones overlie over consolidated shales. The shales are susceptible to creep and strain softening where lateral confinement has been removed by the downcutting of the Colorado River and its tributaries. Strata dipping towards valleys, including dips of 5 degrees or less, greatly impact the number and scale of landslide events. The over consolidated shales also create a permeability barrier, resulting in perched groundwater with numerous springs and seeps emanating immediately above these layers. Most landslides within the study area have not been active in historic times although a few notable exceptions exist. It also appears that a wetter and cooler climate pervaded during some landslide. The saturation of slopes caused by lava dams in the western Grand Canyon and other landslide dams likely played a role. The rapid drawdown conditions/pore pressure imbalances caused when the dams breached catastrophically, and their reservoirs drained likely served as a trigger. These landslides exhibit or created anomalous features not seen anywhere else in the region. These include the Deer Creek Falls and the Granite Narrows, which is the narrowest point along the Colorado River within the Grand Canyon. Surprise Valley is a dry amphitheater between two major tributaries of the Colorado River with no major source of water to carve it. Poncho’s Radical Runup is the dissected remains of one of the highest landslide run up features in North America"--Abstract, p. iv</p>

Name thesis:degree_name

Ph. D. in Geological Engineering

Grantor

Missouri University of Science and Technology

Author dc:creator

• Watkins, Conor Maris

• Colorado Plateau
• Colorado River
• Grand Canyon
• Landslides
• Shales
• Strain Softening
• Engineering
• Geological Engineering

Repository record dc:identifier

https://scholarsmine.mst.edu/doctoral_dissertations/3259

OAI identifier oai:identifier

oai:scholarsmine.mst.edu:doctoral_dissertations-4264