Friday, November 20, 2009
Santa Elena Canyon
Bina and the River that Saved Her
They called her Bina, the Apache name for music maker. She had been playing her flute under a cottonwood tree when they muscled her on the bare back of the palomino. She remembered the taught flank muscles of the horse flexing between her legs as a dark arm wrapped around her, finger nails piercing her side. They galloped across the moon lit desert south toward the river and now three years later she glanced one final time at the mouth of the canyon and the raging waters that had set her free.
The geography of the Big Bend region of Texas over the past 250 million years was formed by a series of compression, volcanism and tension events that created mountain terrain which lent itself to a high degree of erosion. Rapid run-off and flash flooding after thunderstorms is the strongest form of erosion but erosion by way of naturally occurring corrosive chemicals like carbonic acid is also a powerful agent in the geological formation of the area. Calcite which forms the bulk of the limestone in the Big Bend is especially susceptible to break down by carbonic acid.
The formative period of the Santa Elena Canyon likely began about two million years ago, a relatively short period in Earth’s geologic time. The cliffs of the eight mile long, 1500 foot deep canyon run along a fault line. The effect of running water, carbonic acid and the oxygen of water corroding the iron sulfate in the igneous rocks of the canyon, coupled with fault line mechanics eroded and cut deep into the earth’s crust and formed this canyon segment in the watercourse of the Rio Grande.
A series of basin and range topography existed along the future Rio Grande corridor and once the erosion sediment of the higher lands filled the basins, a single flowing conduit linked the Rocky Mountain run-off with the Gulf of Mexico, creating a 1950 mile long waterway and our country’s youngest major river system.
Evidence of pre-historic human settlement in the Santa Elena area date back 10,000 to 12,000 years ago. More recently in the 16th century when Spanish explorers came to the area, they filed written reports with the Spanish Monarchy describing a group of hunter-gatherers known as the Jumano. These tribes may have been related to the Puebloan civilization of Arizona and New Mexico.
Mescalero Apache and Commanche became dominant in the area in the 18th and 19th century. These tribes crossed the Rio Grande both in trade and in warfare with the Spanish and the Jumano.