Khiori's Solitude
Joshua Tree National Park Geology Tour. September 26, 2004 Sunday
1. Why A Valley?
Our first stop is not too far along the road. We are in "Queen Valley" (elevation 4,450', 1356 meters) which is formed by a differing rate of erosion from the valley floor and the hills surrounding.
I should mention here some of the geologic history of the area. The lay of the land is the product of two widely separated geologic time periods. Most of what we see is the erosion of the land after the second of these two events. We are seeing exposure of 1.7 billion year old Pinto gneiss (high grade metamorphic rock) and the younger 85 million year old White Tank monzogranite - which intruded the Pinto gneiss as molten magma.
Next: 2. A Raindrop Divides
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