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 the Crooked River (elev. 2600 ft), making the cliffs about 600 feet high. The origin of the Smith Rock name is uncertain. One story, published the Albany "States Rights Democrat" in 1867, states that Smith Rock was named after John Smith, who was Linn County Sheriff and an Oregon state legislator in the 1850s and 1860s. The newspaper article credits Smith with "discovering" the rock. Another story claims the rock was named after a soldier named Smith who fell to his death from the rock in 1863 while his unit was camped nearby. The State of Oregon obtained the park