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
Acadia Cliffs State Nature Preserve The name derives from the fact that the land was formerly owned by the Acadia Coal Company. The property includes an old millstone quarry, and many old millstones can still be seen on the site, now back in the forest. This nature preserve was established in part to protect the Bradley's spleenwort, "Asplenium bradleyi", which grows there. The spleenwort is a state-listed plant species. Acadia Cliffs State Nature Preserve Acadia Cliffs State Nature Preserve is a state nature preserve in Washington County, Ohio, United States, with a small neck extending into Athens County, Ohio. Covering an area of , it