SGER: Deep Coring of the Valles Caldera, New Mexico to Obtain a Long-Term Paleoclimate Record

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This award, under the auspices of the Small Grants for Exploratory Research (SGER) program, seeks support to obtain and analyze a deep (~100 to 150 meter) sediment core from a lacustrine sequence in the Valles Caldera, northern New Mexico. The research is aimed at piggybacking on efforts by Los Alamos National Laboratory and the US Geological Survey to drill into the caldera in mid-May, 2004. The SGER funds will: 1) supplement drilling depths in the caldera, 2) allow transport of the core to the LacCore facility in Minnesota, and 3) enable preliminary analyses of core materials.The research will focus on determining the paleoenvironmental record of long-lived lakes in the volcanic caldera and ultimately will allow the researcher, and his colleagues, to develop a paleoclimatic record for this part of northern New Mexico over a substantial part of the Quaternary to about 1.25 million years. Research conducted on this core will include developing a preliminary age model (via radiocarbon dating, Argon isotopic age determinations, and tephrochronolgy), sedimentologic and stratigraphic analyses (mineralogy, grain size, sedimentary facies and sedimentary structures including varves if present), and paleomagnetic/rock magnetic analyses of appropriate parts of the core. The researchers expect that the analysis of this lacustrine sediment core will lead to a much better understanding of the nature of climate variability in the American southwest. A strong potential exists that the research team will recover sediments spanning several glacial-interglacial cycles. If this is so, the resulting paleoclimatic record will be one of the longest in the American Southwest and as such will be of wide interest in the paleoclimatic and paleoecologic research community. The results should provide a useful long-term context for understanding past changes in climate and montane ecosystems in the southwest. If the timing of glacial-interglacial cycles can be determined from the Valles caldera records, it would make a very interesting comparison with the Devil's Hole paleoclimatic record from Nevada. Knowledge of climate variability from the American West is sparse due to the dearth of data archives as compared to other regions in the terrestrial environment. A volcanic caldera is not usually described as a paleoclimate archive but, if the researcher and his colleagues are correct in their assumptions and successful in their drilling efforts, they will add substantially to the data available to the broader community. Given the management of Valles Caldera by the US Park Service, any data recovered from the project will be developed into a public display on the natural history of the region.