GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 214-1
Presentation Time: 8:00 AM

UNDERSTANDING THE DYNAMIC INTERACTIONS BETWEEN EARTH-SURFACE PROCESSES AND TECTONICS: OPPORTUNITIES FOR PROGRESS FROM OUTCROP TO GLOBAL SCALES


HUNTINGTON, Katharine W., Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195, KLEPEIS, Keith, Department of Geology, University of Vermont, Burlington, VT 05405, CASSEL, Elizabeth J., Geological Sciences, University of Idaho, 875 Perimeter Drive MS 3022, Moscow, ID 83844, CURRIE, Claire A., Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada, DIBIASE, Roman A., Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, KIRBY, Eric, College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Wilkinson 202D, Corvallis, OR 97331, LANG, Karl A., Dept. of Geosciences, University of Tübingen, Tübingen, 72074, Germany, PAZZAGLIA, Frank, Department of Earth and Environmental Science, Lehigh University, Bethlehem, PA 18015, RIEBE, Clifford S., Geology and Geophysics, University of Wyoming, 1000 E University Ave, Laramie, WY 82071 and ZEITLER, Peter, Earth and Environmental Sciences, Lehigh University, 1 W Packer Ave, Bethlehem, PA 18015, kate1@uw.edu

The idea that atmospheric, surficial and deep Earth processes may be coupled in complex feedback relationships is one of the most fascinating contemporary developments in Earth science. Such feedbacks would have broad implications for understanding links between rheology, deformation and erodability; the evolution of landscapes and sedimentary basins; and tectonic controls on weathering, the carbon cycle and Earth’s habitability. Building on more than two decades of study, here we discuss recent advances in disciplines ranging from geodynamic modeling to geochronology that now set the stage for breakthroughs in our understanding of Earth-surface evolution and its connections to the atmosphere, biosphere and solid Earth.

Recent work suggests that strong couplings between tectonic processes and various portions of the Earth system are more diverse and significant than previously thought—presenting new opportunities for progress integrating field and modeling studies at outcrop to global scales. Geophysical observations and modeling of mantle dynamics show that dynamic topography on the continents can offer rich insight into these interactions at the broadest time and spatial scales. Rapid increases in the quality and resolution of paleoelevation reconstructions and geochronologic datasets are enabling geodynamic models and emerging ideas about the coevolution of landscapes and life to be tested. At finer spatial scales, there is renewed interest in characterizing the influence of rock strength on landscape evolution, which traditionally has been a major limitation to quantitative interpretation of tectonics from topography. At the hillslope scale, new constraints on processes that control near surface rock strength have inspired the idea that topographic and regional tectonic stresses lead to distinctive patterns of subsurface damage, with implications for potential feedbacks among climate, erosion, rock strength, and tectonics. The coupling between subsurface fracturing, flow pathways, and chemical weathering also may impact landscape form and biogeochemical cycles, thus linking these elements back to processes operating at regional and global scales. As these examples show, the path to fundamental advances lies in the true integration of modeling and observational experiments.