Fall 2010 Colloquium Abstracts - Kelin Whipple

October 27, 2010

Interaction Among Climate, Tectonics, and Topography

Kelin Whipple (Arizona State University)

The topography of Earth’s surface is the product of competitive interaction among tectonics, surface mass transport processes (erosion and deposition), and climate. A partial record of tectonic and climatic histories is thus encoded in landforms. Deciphering this partial record requires quantitative understanding of the processes involved and the coupling and feedbacks among climate, topography, erosion rate, and tectonics. A multifaceted, interdisciplinary approach is required for significant progress, ranging from understanding of the surface manifestation of mantle convection, to crustal deformation styles and mechanics, to the mechanics of erosion and deposition, and to operation of the climate system and its interaction with evolving topography and near-surface material properties. In this talk I will emphasize the evolution of topography at the scale of mountain ranges (~10-100 km) in tectonically active settings. I will highlight how studies of landforms can help inform us about spatial and temporal patterns in crustal deformation that produce rock uplift, and place constraints on crustal geodynamics. Examples will include the Himalaya (Nepal and Bhutan), the Tibetan Plateau, and the Peruvian Andes. I will also discuss new work that is using predictions of dynamic topography produced by mantle convection models to develop new hypotheses regarding the uplift history of the Colorado Plateau and their implications for the enigmatic history of Grand Canyon incision. Geologic and geomorphic data can then be used to test these hypotheses and the underlying geodynamic predictions.