Rio Puerco Valley Cretaceous sedimentary rocks

A group of geologists from the NMBGMR and Maya Elrick from the UNM Earth Science Department recently met up in the Rio Puerco Valley to examine Cretaceous sedimentary rocks. The outcrops will be a featured stop during next week’s New Mexico Geological Society Fall Field Conference. The group focused on the sedimentology and stratigraphy of the Mancos Shale and Point Lookout Sandstone, which were deposited in and along a vast inland sea during the Late Cretaceous Period. The Western Interior Seaway covered much of western North America and started to disappear around 70 million years ago, when tectonic forces caused the uplift of the Rocky Mountains.