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 River nutrient loads, high bacterial and salinity levels and low dissolved oxygen. These water quality issues can be attributed to livestock, fertilizer and chemical run off. Sources of run off are croplands, pastures, and industrial sites among others. Fracking is also cause for concern regarding water quality within the Brazos Watershed. The Barnett Shale lies partially within the watershed which is the second largest source of natural gas in the US. Studies have shown that the watershed receiving the most toxic pollution is the lower Brazos river which received 33.4 million pounds of toxic waste in 2012. Canoeing is a very