SEDIMENTARY RECORDS OF
ENVIRONMENTAL CHANGE LABORATORY
The Sedimentary Records of Environmental Change Laboratory analyzes physical, biological, and isotopic properties of sediment, especially from lakes and wetlands, to interpret past environmental changes. The laboratory is a shared-use facility, linked to the Amino Acid Geochronology Laboratory and affiliated with the Colorado Plateau Analytical Laboratory.
- The laboratory is equipped with a Beckman-Coulter LS230 particle-size analyzer, a Bartington MS2 magnetic susceptibility system, instruments for analyzing sedimentary biogenic-silica and organic-matter content, equipment for processing samples for radiocarbon dating, and a cold room for archival of sediment cores from more than 30 lakes.
- The laboratory has expertise in the taxonomy of freshwater ostracodes and houses a reference collection of ostracode valves from the western U.S
- investigating storm-track changes in the North Pacific region over the past several thousand years using the oxygen-isotope composition of diatoms extracted from lake sediment;
- quantifying summer temperature fluctuations during the last several thousand years using the concentration of sedimentary algae (biogenic silica) from Arctic, sub-Arctic, and alpine lakes;
- reconstructing the hydrogeographic and climatologic changes at Bear Lake, Utah-Idaho, using the oxygen-isotope composition of carbonate from a continuous sediment core extending back 250,000 years;
- using ostracode species assemblages to reconstruct the environmental conditions of pluvial lakes in the Mojave Desert during the last ice age;
- assessing the frequency of eruptions from Aleutian Arc volcanoes using ash deposits and other features preserved in lake sediment from southern Alaska.