Advanced Search
Weathered Green Valley Tonalite
Field Collector: Esper Signius Larsen Jr.
Place Collected:Near Vista San Luis Rey Quadrangle, Southern California
Object number: ROC21722
DescriptionDark grey-black sediment from plutonic igneous rock that has been eroded at the surface. According to Larsen (1948) it is not greatly altered and retains original hornblende, not much of it is montmorillonite (clay). It was collected 1-12 in below the surface.
In Collection(s)