Linkages of fluvial terrace formation and geometry to Milankovitch-scale climate change revealed by the chronostratigraphy of the Colorado River above Moab, UT, and regional correlations

Abstract

The Colorado River flows from its Rocky Mountain headwaters to the Gulf of California, draining most of the Colorado Plateau. Although the river’s hydrology is set in the Rockies, its sediment load is largely supplied by the plateau drylands of the lower drainage. Terrace genesis at Milankovitch timescales • Reflects changing dynamics between fluctuating hydrology and local sediment supply? • Relations to major late Pleistocene climate shifts? • Do study terraces correlate regionally? (i.e. are pulses of sedimentation transient or synchronous?) • What controls the formation of fill vs. strath terraces? Deformation of terraces • Is there a detectable influence of salt tectonism on terrace form and type? Our goal is to address these questions through detailed chronostratigraphy, correlation, surveying, and long-profile analysis