Hidden Valley — Granite Creates Shelter in the Desert
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Transcript
Hidden Valley is enclosed by rounded granite outcrops that look as though giant boulders were piled here. The rocks actually weathered from solid masses underground.
Fractures divided granitic rock into blocks. Chemical weathering attacked corners and edges, rounding them while buried. Later erosion removed surrounding material and exposed the boulders.
The resulting walls create shade, wind shelter and pockets where water can linger slightly longer than on open desert flats.
That physical shelter influenced animal movement and human use. The valley later became associated with cattle ranching and stories of rustlers, but the useful geological fact is more basic: granite changed the local microclimate. In a desert, even small reductions in heat and wind can matter.