Measurement of long-term denudation rates in carbonate landscapes using in situ-produced 36Cl cosmogenic nuclide

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Abstract:

ecent progresses have been made in the quantification of denudation of eroding landscapes and its links with topography. Despite these advances, data is still sparse in carbonate terrain, which covers a significant part of the Earth’s surface. We can now measure in situ-produced cosmogenic nuclides concentrations in various near-surface materials, allowing accurate quantification of the rates of geomorphic processes. The significant control of the precipitation gradient on the denudation pattern support the idea that dissolution is the major regulator of the evolution of such landscapes and that physical processes play only a secondary role, unless water availability becomes limiting for chemical weathering. However, in many carbonate landscapes hillslopes terminate upwards to convex hilltops that are commonly associated with diffusion-like regolith transport. These observations suggest that physical weathering and regolith transport may play a significant role in the evolution of carbonate hillslopes in addition to total dissolution.

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volume 1  issue 1

pages  0- 0

publication date 2018-08

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