The Surface Processes Lab at the University of New Mexico, directed by Dr. Marisa Repasch, is dedicated to advancing research on Earth’s dynamic landscapes and their role in the carbon cycle. Located in Northrop Hall, the lab provides state-of-the-art infrastructure for preparing and analyzing rock, soil, and sediment samples to better understand erosion, weathering, and fluvial processes.

Our facility supports a wide range of sample processing and physical analyses. Core capabilities include:

• Particle size and shape characterization with a Malvern Mastersizer 3000+ Ultra laser diffraction analyzer (fine sediment <2 mm) and a Ro-Tap sieve tower (coarse sediment >2 mm).

• Sample preparation with a Retsch M400 ball mill, Thermo Scientific Sorvall ST 16 centrifuge, Mettler Toledo Advanced MS-TS precision balance, reciprocating shaker table, Labconco FreeZone 4.5 L benchtop lyophilizer, and Thermo Scientific Heratherm convection oven.

• Ultrapure water generation via a Thermo Smart2Pure 6UV system coupled to reverse osmosis filtration.

Together, this infrastructure enables detailed analyses of particle size distributions, sediment texture, and sample preparation for geochemical measurements, positioning the Surface Processes Lab as a hub for studying how rivers and landscapes mobilize and transform carbon.

Photo of the Malvern Mastersizer 3000+ Ulta with HydroInsight particle imaging capabilities. This instrument was supported by the National Science Foundation (Award #2412404: EA: Acquisition of sediment characterization instrumentation to catalyze Earth science research at the University of New Mexico).