A question for the ages: “Whither the Rio Grande Rift?”

The Friends of the Colorado School of Mines Geology Museum “First Thursday” lecture series continues this Thursday, March 5th at the Geology Museum, 1310 Maple Street.

This month’s topic will be:  “Whither the Rio Grande Rift?” with Dr. Vincent Matthews, former State Geologist of Colorado and currently Principal of Leadville Geology LLC.

The Rio Grande Rift cuts through Central Colorado and is undergoing measurable extension today. The northern terminus of the Rio Grande Rift has puzzled many. Some suggest it ends at Leadville on the northern end of the Upper Arkansas Valley, some suggest it continues northward to Kremmling, some suggest it continues into North Park, and some have even suggested it continues on to Yellowstone. Others proposed that the Rift wraps around the Aspen Anomaly, or continues out through northwestern Colorado.
This talk reviews the evolution of thinking on the Rio Grande Rift and presents data that its extension form the eastern and northern boundary of the “structural” Colorado Plateau. The northeastern corner of the structural Plateau is located just south of Steamboat Springs, Colorado. The northern boundary of the Plateau is defined by a broad zone experiencing north-northeast extension which is defined by a distributed zone of Late Cenozoic faulting, numerous stress indicators, and basaltic volcanism. The entire system can be explained by a clockwise rotation of the Colorado Plateau away from its northeastern corner.

Socializing and munchies begin at 6:30 PM; the talk will start at 7:00.  Admission is free!