June 2, 2022
A new paper in GEOLOGY co-authored by bureau geologist Matt Zimmerer focuses on the build-up to climactic supervolcano eruptions. Using more than a decades worth of radiometric dates generated in the bureau's geochronology lab, in combination with mapping by the USGS, researchers discovered a pattern in the small-volume eruptions that predate larger-volume caldera-forming eruptions. This work shows that prior to supervolcanic eruptions many volcanic fields enter a period of reduced activity for ~500,000 to 2-million-years. During this time, magma accumulates (rather than erupts) into the large volume reservoirs that ultimately lead to a supereruption. Although the study focused on extinct volcanoes in southern Colorado, the work has important implications for young volcanic systems that are currently in dormant periods of activity, such as NM’s Valles caldera.
Early incubation and prolonged maturation of large ignimbrite magma bodies: Evidence from the Southern Rocky Mountain volcanic field, Colorado, USA
— Peter W. Lipman, Matthew J. Zimmerer, and Amy K. Gilmer, Geology (2022), https://doi.org/10.1130/G49964.1