Kurt Frankel

My research is focused on the interaction between active tectonics and geomorphology. I use a multidisciplinary approach to field-based, process-oriented research in subject areas ranging from examining the constancy of seismic strain accumulation and release along major plate-boundary fault systems to investigating tectonic and climatic controls on range-scale erosion and exhumation.

The primary questions my research addresses are: (1) how temporally and spatially constant is strain accumulation and release? For example, are intermediate- to long-term fault slip rates averaged over thousands to millions of years compatible with short-term (decadal) geodetic rates? (2) How does the landscape respond to climatic and tectonic forcing and are there distinct topographic or erosional signatures of these forces? (3) Is alluvial fan deposition controlled primarily by climate or tectonics and how, and at what rates, do alluvial landforms evolve through time? (4) What are the dominant controls on the rates and style of bedrock channel incision and knickpoint evolution?

In order to approach these questions, my investigations always start with detailed observations of the landscape. Thus, my research involves a significant field component including surficial and bedrock mapping, geochronologic sample collection, and defining Quaternary stratigraphy. Topographic analyses of high-resolution digital elevation data using geographic information systems (GIS) along with satellite imagery and aerial photograph interpretation complement my field observations. In particular, much of my recent work has focused on using airborne laser swath mapping (ALSM; also known as LiDAR) digital topographic data to investigate fault slip rates and alluvial landform evolution. These state-of-the-art digital data are allowing researchers to quantify fault slip rates and landscape processes in unprecedented detail.

Geochronology is another critical aspect of my research. I use cosmogenic nuclide (TCN) and optically-stimulated luminescence (OSL) geochronometers to determine rates and processes of tectonic deformation and landscape evolution. Cosmogenic nuclides are particularly useful for geomorphology because they provide ages on previously undateable landforms. In addition, concentrations of cosmogenic nuclides in alluvial sediment are useful for determining catchment-wide erosion rates. I am also interested in direct comparisons of the ¹⁰Be and ³⁶Cl cosmogenic nuclide systems and the evaluation of different cosmogenic techniques as well as cross-chronometer calibrations (e.g. TCNs vs. OSL). These assessments are crucial to our understanding of the advantages, limitations, and uncertainties associated with the various methods.

In addition to my field and analytic research activities, I have conducted analogue modeling of fluvial systems to investigate bedrock channel incision processes. This research is driven by the observations of numerous knickpoints in the Appalachian Mountains. Although issues of scaling are often problematic for such models, simple “sand box” experiments can improve our understanding of complicated processes because many variables can be controlled. This allows specific parts of a geologic system to be isolated and observed, something which often cannot otherwise be accomplished on human time scales.

Recent Collaborators: