Weathering and the Evolution Bedrock Channel Longitudinal Profiles: A Beginning

My name is Max Cunningham.  I’m a rising senior, and I like to think of myself as a geologist-in-training.

When I explain to people that I study “geology,” the typical response goes something like: “so you study rocks?”  In most cases this is a vast oversimplification of Earth science, but in many ways I will be doing precisely that this summer.  Perhaps a better synopsis of my work is that I will be learning more about how streams carve out the bedrock on which our society sits.

At its heart, geology is a study of change.  The Earth is in a constant state of movement, even if it’s completely imperceptible to the human eye.  My field of study is geomorphology, or how landscapes are change through time.  It’s useful to understand this kind of thing for a variety of reasons, such as land use planning or land restoration after resource development.  This summer I will study one important aspect of landscape evolution modeling: the incision of bedrock streams.  Landscape change in certain regions is set by how quickly streams cut into bedrock, and how surrounding hillslopes respond to that incision.

Specifically, my research will refine bedrock channel incision models by exploring how various processes prepare bedrock channels for stream erosion, broadly referred to as “weathering.”  I am joining the third year of a larger study conducted by my research advisor, Dr. Greg Hancock.   While current bedrock channel erosion models predict that channel geometry will change consistently along a stream, Dr. Hancock’s research team has observed variable channel erodability along channel cross-sections due to weathering.  The implication is that weathering may be affecting channel shape, and therefore channel evolution, along entire bedrock streams (easier referred to as the stream’s “longitudinal profile”).  My work this summer will involve discerning the effect that weathering may have on channel longitudinal profiles, and whether variation from predicted channel geometry along those profiles can be attributed (at least in part) to weathering.

My project is being supported by the generosity of Girton and Bright Families Scholarship, supporters of W&M’s Honors Fellowship Program and the Charles Center.  I am grateful for this support and the opportunity to make contributions to geologic research.  I’m looking forward to a beautiful summer and soaking in the excitement, frustration and joy that inevitably accompany research.