| Field Trip Description: This one-day trip will visit the West Bijou Creek exposure of the K-T boundary which is located 40 miles east of Denver in the center of the Denver Basin. This boundary section contains all of the classic indicators of the K-T boundary including Cretaceous and Paleocene plant and vertebrate fossils, evidence of magnetic polarity subchron C29r, anomalous iridium concentrations, shocked minerals, and a negative carbon isotope excursion. In addition, the 40 meter section that contains the K-T boundary also contains a number of volcanic tuffs, some that closely bracket the K-T boundary and provide the opportunity to increase the precision on the age of the K-T boundary. This outcrop is under detailed study as part of the ongoing EARTHTIME initiative. This fieldtrip will allow examination of several different tuffs with a range of outcrop attributes and discussion of their field expression, mineralogy, and geochronology. Trip participants will be able to observe fossils and tuffs in their stratigraphic context and to see the results of integrated paleontological, geochemical, and geochronological analyses. Collecting of samples will not be allowed. A box lunch will be provided. |