Centuries of wind and water erosion and earth movement have created some beautiful and fascinating stone landmarks in Anza and Aguanga.
The geology of the Anza Valley is ancient, having gained many of its features during the Mesozoic era, an interval of geologic time from about 252 to 66 million years ago. This period was a time of significant tectonic activity. Scientists theorize that during this era the gradual shifting of the supercontinent Pangaea into separate land masses occurred. Volcanic activity and earthquakes helped form the Anza landscape.
One of the most obvious geological aspects of the valley are the granite boulders and rocks. Granite is an igneous stone that is formed over time by volcanic activity. Magma flows from volcanic hot spots and slowly cools over millions of years. During the process, the magma combines with various minerals including hornblende, feldspar, mica and quartz to create granite’s particular appearance.
Erosion exposes large deposits of granite and smooths the boulders into various shapes.
Fires and earthquakes can cause these granite giants to split and shed pieces, creating boulder gardens and caves.
These rock structures are home to animals, insects, mosses, lichens and birds.
Diane Sieker can be reached by email at email@example.com.