How does anisotropy in bedrock river granitic outcrops influence pothole genesis and development? |
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| Authors: | Jose Ortega‐Becerril Miguel Gomez‐Heras Rafael Fort Ellen Wohl |
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| Institution: | 1. Departamento de Geología y Geoquímica, Universidad Autónoma de Madrid, Madrid, Spain;2. Instituto de Geociencias (CSIC, UCM), CEI‐Moncloa, UCM‐UPM, CSIC, Madrid, Spain, Madrid, Madrid, Spain;3. Department of Geosciences, Colorado State University, Fort Collins, CO, USA |
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| Abstract: | Pothole formation and development may be influenced by joint sets and other heterogeneities within bedrock, as well as by hydraulics. Previous research indicates that most potholes found in rivers of the mountainous Spanish Central System exhibit preferred orientations associated with dominant joints and correlate more strongly with variations in substrate resistance than with hydraulics. Weathering and erosion weaken rock surfaces, which leads to decreased mechanical resistance. We start from the hypothesis that different mechanisms of pothole formation may create around the pothole a distinctive signature in terms of ultrasound pulse velocity and surface hardness. We develop a conceptual model and test it using potholes for which we know the mechanism of formation, demonstrating that the spatial and statistical distributions of dynamical mechanical properties and surface hardness of a pothole may provide insight into its genesis. Copyright © 2016 John Wiley & Sons, Ltd. |
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| Keywords: | potholes anisotropy weathering ultrasound Schmidt hammer |
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