November 29, 2021
Bureau field geologists Dan Koning, Jacob Thacker, and Snir Attia joined John Nelson and Scott Elrick of the Illinois State Geological Survey to map folded strata in the Little San Pascual Mountains that sit just east of the Bosque Del Apache. This small mountain range was uplifted during formation of the Rio Grande Rift, but the complexly folded limestones exposed here were deposited over 300 million years ago in the Pennsylvanian! The complex folding and more cryptic, associated faulting likely resulted from regional contraction during the Late Cretaceous Laramide Orogeny. Bureau geologists and our colleagues from the Illinois State Geological Survey have been mapping related strata and structures in adjacent areas to the north and south for a long time.
— Snir Attia, Field Geologist, NMBGMR