Brazos Mountains to 55 million years ago during the Laramide orogeny. To the east and northeast lie the Sangre de Cristo Mountains which share a similar geological history. The Brazos Cliffs, which form a dramatic backdrop to Tierra Amarilla, are formed of Precambrian quartzite. Brazos Mountains The Brazos Mountains is a range in far northern Rio Arriba County, in northern New Mexico in the southwestern United States. A high crest runs from the border with Colorado for over in a south-southeasterly direction. The high point of the range at is on Grouse Mesa, at the Brazos Benchmark. Two miles (3 km) to
Smith Rock State Park Smith Rock State Park Smith Rock State Park is an American state park located in central Oregon's High Desert near the communities of Redmond and Terrebonne. Its sheer cliffs of tuff and basalt are ideal for rock climbing of all difficulty levels. Smith Rock is generally considered the birthplace of modern American sport climbing, and is host to cutting-edge climbing routes. It is popular for sport climbing, traditional climbing, multi-pitch climbing, and bouldering. The geology of Smith Rocks is volcanic. It is made up of layers of recent basalt flows overlaying older Clarno ash and tuff formations. Approximately 30 million