Slow Landslide Processes
While some landslides fail catastrophically, others exhibit slow seasonal slip, often amounting to only centimeters to meters per year. What determines which of these two differing modes of behavior dominates remains a key problem in landslide mechanics and natural hazard prediction. We are investigating the physical processes that are thought to govern slow slip in landslides at Oak Ridge Earthflow (at left) near San Jose, CA.
What governs the mobility of coarse sediment? How does this shape the hydraulic geometry of river channels? We are tackling these and other related questions through field and experimental studies.
Pfeiffer, A,M., Finnegan, N.J., and Willenbring, J.K., Sediment supply controls equilibrium channel geometry in gravel rivers, 2017, Proceedings of the National Academy of Sciences, doi: 10.1073/pnas.1612907114. [link]
Masteller, C.C., and Finnegan, N.J., Interplay between grain protrusion and sediment entrainment in an experimental flume, 2016, Journal of Geophysical Research Earth Surface, 122, p. 274–289. [link]
Roth, D., Brodsky, E. E., Finnegan, N.J., Rickenmann, D., Turowski, J., and Badoux, A., 2016, Bedload sediment transport inferred from seismic signals near a river, Journal of Geophysical Research Earth Surface, 121, p. 725–747. [link]
Unglaciated topography is shaped by competition between tectonic uplift and climate-driven bedrock river incision. We are investigating the processes that shape bedrock channels, as well as the ways in which river canyons encode information about climatic and tectonic forcing
Perkins, J.P., Finnegan, N.J., and de Silva, S.L., 2015, Amplification of bedrock canyon incision by wind, Nature Geoscience, DOI: 10.1038/NGEO2381 [link].
Johnson, K.N., and Finnegan, N.J., 2015, A lithologic control on active meandering in bedrock channels, Geological Society of America Bulletin,doi: 10.1130/B31184.1. [link].
Finnegan, N.J., Schumer, R., and Finnegan, S., 2014, A signature of transience in rates of river incision into bedrock over timescales of 104-107 years, Nature, 505, 391-394 [link].
We use topography to constrain the record of surface deformation above active volcanoes over millennial timescales.
Perkins, J.P., Ward, K.M., de Silva, S.L., Zandt, G., Beck, S.L., and Finnegan, N.J., Surface uplift in the Central Andes driven by growth of the Altiplano Puna Magma Body, 2016, Nature Communications, DOI: 10.1038/ncomms13185. [link]
Perkins, J.P, Finnegan, N.J., Henderson, S., and Rittenouer, T.M., 2016, Topographic constraints on magma accumulation below the actively uplifting Uturuncu and Lazufre volcanic centers in the Central Andes, Geosphere, 12, p. 1078-1096. [link]