Quaternary Landscape Evolution
During the Quaternary, large deep-seated landslides were initiated along the eastern flank of the Colorado Front Range, and rivers cut and deposited large strath terraces along the western High Plains. These are the most extensive and prominent geomorphic features in the landscape. On this field trip, we will explore the Quaternary evolution of these Front Range features, in addition to viewing the smaller erosion scars and deposits associated with a 1000-yr precipitation event in 2013. We begin the trip near Golden, Colorado, where we will view the most extensive Quaternary strath terrace (Rocky Flats) preserved in the Denver Basin. We then head to Boulder, Colorado, to view the contrast between recent debris flows and deep-seated Quaternary landslides. Near Lefthand Creek, north of Boulder, we will view a suite of strath terraces and discuss the cosmogenic radionuclide dates that indicate both rapid incision and a new version of the terraces ages. Throughout the day, we will focus on the geomorphic work done by rare events, as well as discuss numeric and relative dating of Quaternary terraces and landslides.
Figures & Tables
Prepared in conjunction with the 2016 GSA Annual Meeting in Denver, Colorado, this volume contains sixteen guides to field trips in this rich geologic region. The four “Great Surveys” of the late 1800s ventured west to explore and document the region’s unknown natural resources and collect valuable geologic information. Many of the field guides in this volume, aptly titled Unfolding the Geology of the West, will cover the same hallowed ground as the early geologic expeditions. Organized into four sections, this volume spans some of the major subdisciplines of geology: (1) stratigraphy, sedimentology, and paleontology; (2) structure and metamorphism; (3) Quaternary landscape evolution; and (4) engineering and environmental geology.