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
Brazos Island and the Rio Grande river. Brazos Island State Scenic Park, also known as Brazos Island State Recreation Area, is located on the island. The beach at this state park is known as "Boca Chica." Brazos Island Brazos Island, also known as Brazos Santiago Island, is a barrier island on the Gulf Coast of Texas in the United States, south of the town of South Padre Island. The island is located in Cameron County. The island is also known as Brazos Santiago Island, a reference to the port of Brazos Santiago, the first Spanish settlement on the island. Later it became