This document summarizes different types of rocks found in Parkfield, California through descriptions and photos provided by a geologist. It describes sedimentary rocks like marine sediment containing seashell fossils over 10 million years old. It also describes igneous rocks like volcanic rocks with gas pockets and granite from Yosemite. Additionally, it summarizes a metamorphic rock sample from the Calaveras formation displaying changes from heat and pressure. The document credits the geologist Andy Snyder for providing the rock samples and information.