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Casa Grande, Big Bend (C)
Casa Grande (Spanish for “big house”), at 7,315 feet is not the highest peak in the Chisos Mountains of Big Bend National Park, but it is the most distinctive and recognizable. It does not look much like a big house from this direction, but from other directions it does. This was taken about halfway up the Lost Mine Trail.
It was formed in a different way from most mountain peaks. Some 35 million years ago, molten rock began pushing toward the surface. It finally broke through, and spread lava over a considerable area. The softer rock, through which the lava had pushed, began eroding away. Where the supporting rock had been removed, the lava was unsupported, and broke off.
In the intervening 35 million years, The supporting rock has eroded down to the level from which the picture was taken, some1,500 feet below the summit.