Cohesive Channels


Engineering and Applied Sciences


Graduate Chair and Associate Professor of Earth and Environmental Science

Project Summary

This summer, I had the opportunity to work in the Penn Sediment Dynamics Laboratory under the mentorship of Dr. Douglas Jerolmack and graduate student Kieran Dunne. The project I worked on studied the relationship between sediment size, erodibility, and the shape of a river bed. Previously, researchers have created and proved theories about erosion with smaller sediments, like clay and silt, and others have developed theories with larger particles, such as sand or gravel. The goal of this project is to develop a unifying theory that combines the two seeming contradictory theories into one.

By collecting data from rivers such as the Mullica River in Hammonton, New Jersey, we observed differences in the composition of bank material and bed material. Our team used field surveying equipment such as laser range finders and shear vanes to measure cross sections of the river channel and bank shear strength, respectively. We also collect samples at each cross section. Overall, we recorded data from over 50 cross sections, and collected approximately 150 samples. Using lab techniques, we are able to determine the ratio of small sediments to large sediments at each cross section, and compare it to the shape of the channel. Through this comparison, we can find trends between sediment size and geometry of the channel cross section, and ultimately draw conclusions about the erodibility of the different sediments.

Through this summer, I learned that research can be fun! The days spent in the field can be long and tedious, but I am reminded of the uniqueness of my experience: I get to spend my summer in the outdoors, while also participating in research. I also learned the value of collaboration in research, through the many questions asked to other graduate students or post-docs in the lab group, as well as the use of others’ papers to bolster your own.

This project led me to learn how to code in Python -- very basic coding, but coding, nonetheless. I came in with absolutely no prior coding experience, so it was a slow process for me. Using my newfound knowledge, I was able to process the data much quicker than if I were to try to parse through all the data by hand. Generally, I was also introduced to the basic concepts of sediment flow, and got a sneak peek into the world of geomorphology. Participating in this project gave me a greater appreciation for earth sciences and the work that goes behind collecting data for research.

Cohesive Channels