Weathered Woodson Mountain Granodiorite
Field Collector: Esper Signius Larsen Jr.
Place Collected:Near Rainbow San Luis Rey Quadrangle, Southern California
Object number: ROC21724
DescriptionOrange-yellow plutonic igneous rock that has been significantly altered by weathering at the surface to clays. Larsen (1948) reports that most of the plagioclase has been altered to montmorillonite (clay). It was collected 6-12 inches below the surface.