Which formations are separated by the San Andreas Fault?

The correct answer identifies the distinct geological formations separated by the San Andreas Fault, specifically the Franciscan Formation and the Salinian Block.

The San Andreas Fault is a major transform fault that delineates the boundary between the Pacific Plate and the North American Plate. This fault system plays a crucial role in the geological landscape of California by marking the separation between different rock types and formations.

The Franciscan Formation primarily consists of metamorphic rocks, including schist and other sedimentary sequences, and is known for its complex geology that has been influenced by tectonic forces over millions of years. Meanwhile, the Salinian Block is characterized by granitic rocks and includes younger formations that have been uplifted and exposed due to tectonic activity. The fault therefore not only separates these two distinct geological formations, but it also exemplifies the dynamic tectonic processes that shape the geology of California.

Understanding the distinction and location of these formations aids in the comprehension of local geology, earthquake hazards associated with the San Andreas Fault, and regional tectonic history.