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
Starved Rock State Park the National Register it had been determined that there were three "village and mound" sites within the park. Besides Corbin Farm and Little Beaver, the Simonson site, an open-air occupation site, is also considered a village and mound site. Simonson Site has faced significant alterations over the years Approximately 150 different types of plants grow at Starved Rock State Park. On the sandstone cliffs of Starved Rock State Park white pine, Canada yew and northern white cedar are found; these plants are more commonly found further north. On the surfaces of the canyons and cliffs, where it is cooler, other