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Showing 1 to 9 of 9 for “"cosmogenic radionuclides"”.
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THE PACE AND TIMING OF CHANGING LANDSCAPES AS VIEWED THROUGH COSMOGENIC RADIONUCLIDES: SYNTHETIC AND REAL EXAMPLES FROM THE CENTRAL ANDES AND AMAZONIA
<p>In the past three decades, the use of cosmogenic radionuclides revolutionized research in geomorphology. Cosmogenic radionuclides, such as 10Be and 26Al, accumulate within quartz crystals at a relatively well-constrained rate due to the bombardment of the Earth’s atmosphere by cosmic rays. Since …
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Geomorphic and thermochronologic signatures of active tectonics in the central Nepalese Himalaya
… topographic data, ⁴⁰Ar/³⁹Ar thermochronology, cosmogenic radionuclides, and thermal modeling, to determine whether this break in landscape morphology reflects active tectonic displacements at the foot of the Himalaya. The goals of the thesis are 1) to understand the degree to which landscape …
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Topographic asymmetry and climate controls on landscape evolution
… beheadings, and erosion rates determined from cosmogenic radionuclides to determine which asymmetry forming mechanisms are likely responsible for the topographic asymmetry at Gabilan Mesa, a landscape in the central California Coast Ranges. I find that aspect-dependent differences in runoff are …
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Assessing Holocene and late Pleistocene geomagnetic dipole field variability
… to environmental change and measurement of cosmogenic radionuclides. The results are used to date the sediments and to study regional and global geomagnetic field variations over the past 50,000 years. The Holocene dipole tilt variation is reconstructed by averaging virtual geomagnetic poles …
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Tectonic Exhumation and Climate Driven Erosion in Extensional Mountain Blocks: Two Examples from California, USA
… fault zone. Second, I present a new data set of cosmogenic radionuclide-derived burial ages and paleodenudation rates (26Al/10Be) from the Pleasant Canyon complex in the Panamint Range, and show that denudation rate and sediment flux have varied by a factor of ~2x since the middle Pleistocene. I …
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The Impacts of Climate and Landscape Change on Catchment Scale Material Transport in High Mountain and Seasonally Cold Regions
… over much longer timescales by utilizing cosmogenic radionuclides in several watersheds in the Argentine high Andes. First, 10Be in river sand was used to estimate catchment-wide erosion rates at the millennial scale and compared to decadal scale erosion rates from steam gauge data, with …
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Evaluation of Coupled Erosional Processes and Landscape Evolution in the Teton Range, Wyoming
… Detrital apatite (U-Th)/He thermochronology and cosmogenic radionuclide erosion rates were applied to determine spatial and temporal variability of erosion in the central catchments of the range. Spatial variability existed between the glacial and fluvial systems, indicating that sediment erosion …
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Denudation processes in a tectonically active rift on different time scales
… increased humidity. This assessment is based on cosmogenic nuclide (10Be) dating of quartzitic deltaic sands that were deposited in the northern Kenya Rift during a highstand of Lake Suguta, which was associated with the Holocene African Humid Period. Taken together, my new results document the …
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Ανασύνθεση παλαιοπεριβάλλοντος σε παράκτιες γεωμορφές της νότιας Κύπρου με την χρήση τεχνικών φωταύγειας
… common methods applied to minerals’ dating are cosmogenic radionuclides, Electron Spin Resonance (ESR) and luminescence techniques. The latter were initially used to date burned minerals from archaeological artefacts (Thermoluminescence (TL) method). However, advancements of this technique led …