08/16/2026
Last month Bucknell Geology major Anna Solar '27 and geomorphology professor Ellen Chamberlin spent almost two weeks in central and northern Alaska, studying deposition of fine-grained sediments in gravelly braided rivers.
For her senior thesis, Anna sampled silt and sand from 4 Alaskan rivers: the Gerstle and Johnson rivers in the Alaska Range, and the Dietrich and Atigun rivers in the Brooks Range. The Alaska Range rivers have large glaciers in the watershed with very high silt loads; in the Brooks Range, the dry climate means there are no glaciers, so the rivers have much less silt in suspension. Anna is testing whether this contrast in glacial silt supply makes a difference in the channel deposits, which is important for fish and invertebrate habitat, detecting glacial intervals in Earth's past, and for permeability of reservoir rocks.
Anna and Ellen were joined in the field by Liz Hajek (Penn State geosciences professor), and Molly O'Halloran '22, a Bucknell geology department alum who is now working on her PhD in river sediments at Colorado School of Mines.
While in the field, the crew saw lots of moose, sampled silt with wolf tracks on it, and drove a truck almost to the Arctic Ocean!
Interested in field research or learning more about Bucknell geology? Check out our department website: https://coursecatalog.bucknell.edu/collegeofartsandsciencescurricula/areasofstudy/geologygeol/
