The Laramide orogeny (~80–55 Ma) is arguably the most enigmatic North American mountain-building event in the last 250 Ma. Despite decades of research, the mechanism behind the deformation (e.g. flat-slab subduction, transpressional collision, increased plate convergence rates, magmatic thickening, or a combination of these processes) and timing, magnitude and rate of surface uplifts remains controversial. The Colorado Front Range, in the backyard of Denver, provides an excellent setting to study the timing, rate and magnitude of surface uplift on, and relief across, the eastern Laramide deformation front during initial orogenesis. Laramide synorogenic basins flank the Front Range, record the uplift of this mountain belt, and contain a wealth of fossil plants and an abundance of datable rocks. Dr. Miller and colleagues are using a combined approach that utilizes paleobotany, isotope geochemistry, stratigraphic analysis, geochronology, and thermochronology to provide direct estimates of Paleocene topography on the Colorado Front Range.
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