Research

My research focuses on surface processes and landscape evolution. It combines geology, soil science, geomorphology and fracture mechanics. I use the theory and methods of all of these disciplines to explore past and modern processes affecting the surface of the Earth.

Soil Geomorphology.  What is that? Well, soil geomorphology consists of a community of geologists who study soils and weathering in the context of landscapes, geology and surface processes within the ‘critical zone’ the part of Earth that spans vegetation down to unweathered bedrock. We use our understanding of the weathering of rock and sediment to open doors to understanding Earth’s surface. This weathering perspective is critical to the correct interpretation of everything from deposit ages to ‘soil production’ – the conversion of bedrock to dirt – rates that are derived from cosmogenic radionuclides. For example, we use observations of weathering to evaluate the erosion history or stability of a hillslope. We examine how weathering affects hydrologic propoerties of sediment or rock. We use weathering observations to determine the last time that a fault trace ruptured.

Natural Rock Fracture as it relates to Surface Processes. The physical breakdown of rock is key to all subseqent surface processes. Yet, the actual cracking processess of rock have been largely overlooked in surface processes literature. In particular, I have been exploring how subcritical crack growth processes play a role in mechanical weathering (see Eppes & Keanini, 2017). Subcritical crack growth occurs as very low stresses and has been recognized as an important contributor to cracking by engineers and geophysicists. Geomorphologists have largely ignored the potential role that these processes play in weathering. Through field data collection, modeling and instrumentation, I am shedding light on this important new paradigm for mechanical weathering on Earth and other planets.