The Point Reyes Peninsula has long baffled geologists. Why should the rocks of this craggy coast match rocks in the Tehachapi Mountains more than 310 miles to the south? The answer lies in plate tectonics and the continual motion of the Earth’s crust.
Geologically, Point Reyes National Seashore is a park on the move. The eastern border of the park parallels the San Andreas Fault, which is the current tectonic plate boundary separating the Pacific Plate from the North American Plate.
The remaining sides of the peninsula are intermittently edged by beaches, sea cliffs, and intertidal zones cascading into the Pacific Ocean. Encircled by this rich assemblage is a mosaic of ecosystems arranged by factors such as geologic foundation, climate, and exposure. While there are dozens of ways to classify and name the exact type of ecosystem, the broadest and closest category places Point Reyes National Seashore into a Mediterranean Ecosystem.National Parks Service
This can be a forbidding place, a world foreign to outsiders. Medicine Lake is a shield volcano that’s been active for 500,000 years. Its eruptions, from surface vents have been gentle rather than explosive. The eruptions resulted in a low, gently sloping shield-like profile.
The Modoc and their ancestors called Lava Beds home for over 10,000 years. Following the rhythm of nature, they roamed this land freely until they were forcibly moved to the Klamath Reservation in nearby Oregon.National Parks Service
Superlatives abound when a person tries to describe old-growth redwoods: immense, ancient, stately, mysterious, powerful. Yet the trees were not designed for easy assimilation into language. Their existence speaks for themselves, not in words, but rather in a soft-toned voice of patience and endurance.Source: National Parks Service
Located near the San Andreas Fault along the boundary of the Pacific Plate and the North American Plate, Pinnacles [National Park] is an excellent example of tectonic plate movement.
The Pinnacles Rocks are believed to be part of the Pinnacles-Neenach Volcanic Field that occurred 23 million years ago near present-day Lancaster, California, some 195 miles (314 km) southeast. The giant San Andreas Fault split the volcano and the Pacific Plate crept north, carrying the Pinnacles. The work of water and wind on these erodible volcanic rocks has formed the unusual rock structures seen today. Today, these rocks give many species of plants and animals a place to call home.
Geologic forces have created the landscape of Pinnacles, but a climate of hot dry summers and winter rains has also shaped the terrain. The vegetation of the park transforms each year as the rain stops and temperatures climb; hillsides go from vibrant green to golden brown within days.Source: National Parks Service
The last post for this Californian trip, this series of pictures was taken around Morro Bay while on our way to San Francisco.
Hence, the itinerary was as follows:
San Francisco –> Crescent City –> Yuba City –> Los Angeles –> Laguna Beach –> San Diego –> Las Vegas –> Santa Barbara –> Morro Bay where we then followed US 1 north to San Francisco