Grain size distributions (GSD) for samples collected across the Rio Grande Delta upstream of Elephant Butte Reservoir (July 2021-September 2022)

Grain size distributions (GSD) were determined in the lab for four sample types: bed material, suspended sediment, reservoir water, and stratigraphic column samples. Sediment samples were collected from the Rio Grande Delta upstream of Elephant Butte Reservoir in New Mexico during four field campaigns spanning between July 2021 and September 2022: (1) July 4-6, 2021, (2) March 20-22, 2022, (3) May 6-8, 2022, and (4) September 16-18, 2022. GSD were averaged over 5 total measurements with a Malvern Mastersizer 3000 laser diffraction grain size analysis system with a Hydro LV dispersion unit. The purpose of this analysis was to characterize the grain sizes of sediments in the Rio Grande Delta for material finer than gravel (sand, silt, and clay).