The San Francisco Peninsula is a peninsula in the San Francisco Bay Area that separates San Francisco Bay from the Pacific Ocean. On its northern tip is the City and County of San Francisco. Its southern base is Los Altos, Mountain View, in Santa Clara County, south of Palo Alto and north of Sunnyvale and Los Altos. Most of the Peninsula is occupied by San Mateo County, between San Francisco and Santa Clara counties, and including the cities and towns of Atherton, Belmont, Brisbane, Burlingame, Colma, Daly City, East Palo Alto, El Granada, Foster City, Half Moon Bay, Hillsborough, La Honda, Loma Mar, Los Altos, Los Altos Hills, Menlo Park, Millbrae, Mountain View, Pacifica, Palo Alto, Pescadero, Portola Valley, Redwood City, Redwood Shores, San Bruno, San Carlos, San Mateo, South San Francisco, Sunnyvale, West Menlo Park and Woodside.
The San Andreas Fault is a continental right-lateral strike-slip transform fault that extends roughly 1,200 kilometers (750 mi) through the U.S. state of California. It forms part of the tectonic boundary between the Pacific Plate and the North American Plate. Traditionally, for scientific purposes, the fault has been classified into three main segments, each with different characteristics and a different degree of earthquake risk. The average slip rate along the entire fault ranges from 20 to 35 mm per year.
State Route 1 (SR 1) is a major north–south state highway that runs along most of the Pacific coastline of the U.S. state of California. At 656 miles (1,056 km), it is the longest state route in California, and the second-longest in the US after Montana Highway 200. SR 1 has several portions designated as either Pacific Coast Highway (PCH), Cabrillo Highway, Shoreline Highway, or Coast Highway. Its southern terminus is at Interstate 5 (I-5) near Dana Point in Orange County and its northern terminus is at U.S. Route 101 (US 101) near Leggett in Mendocino County. SR 1 also at times runs concurrently with US 101, most notably through a 54-mile (87 km) stretch in Ventura and Santa Barbara counties, and across the Golden Gate Bridge.
Colma is a small incorporated town in San Mateo County, California, United States, on the San Francisco Peninsula in the San Francisco Bay Area. The population was 1,507 at the 2020 census. The town was founded as a necropolis in 1924.
Daly City is the second most populous city in San Mateo County, California, United States. The population was 104,901 at the 2020 census. Located in the San Francisco Bay Area, and immediately south of San Francisco, it is named for businessman and landowner John Donald Daly.
A raised beach, coastal terrace, or perched coastline is a relatively flat, horizontal or gently inclined surface of marine origin, mostly an old abrasion platform which has been lifted out of the sphere of wave activity. Thus, it lies above or under the current sea level, depending on the time of its formation. It is bounded by a steeper ascending slope on the landward side and a steeper descending slope on the seaward side. Due to its generally flat shape, it is often used for anthropogenic structures such as settlements and infrastructure.
The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie within Santa Barbara, Ventura, Los Angeles, San Bernardino, Riverside and Kern counties. The Peninsular Ranges lie to the south. The name is due to the ranges' east–west orientation, making them transverse to the general northwest–southeast orientation of most of California's coastal mountains.
The Los Angeles Basin is a sedimentary basin located in Southern California, in a region known as the Peninsular Ranges. The basin is also connected to an anomalous group of east-west trending chains of mountains collectively known as the Transverse Ranges. The present basin is a coastal lowland area, whose floor is marked by elongate low ridges and groups of hills that is located on the edge of the Pacific Plate. The Los Angeles Basin, along with the Santa Barbara Channel, the Ventura Basin, the San Fernando Valley, and the San Gabriel Basin, lies within the greater Southern California region. The majority of the jurisdictional land area of the city of Los Angeles physically lies within this basin.
Goat Rock Beach is a sand beach in northwestern Sonoma County, California, United States. This landform is a sub-unit of Sonoma Coast State Beach, owned and managed by the State of California. At the northern terminus of Goat Rock Beach is the mouth of the Russian River, and the southern end of this crescent shaped expanse is the massive Goat Rock, an iconic outcrop of the Sonoma Coast, which is barely attached to the mainland by a narrow isthmus.
San Bruno Mountain is a fault-block horst in northern San Mateo County, California. Rising to a quarter-mile high peak directly out of San Francisco Bay, it also includes a smaller ridge in San Francisco. Viewed from downtown San Francisco, the mountain occupies the southern horizon. It is surrounded as well by the cities of Brisbane, Colma, Daly City, and South San Francisco, and has an important role in the history and life of these communities.
Seal Rock is a group of small rock formation islands in the Lands End area of the Outer Richmond District in western San Francisco, California. They are located just offshore in the Pacific Ocean, at the north end of the Ocean Beach, near the Cliff House and Sutro Baths ruins.
Rockaway Beach is a shoreline area of the Pacific Ocean in the southern portion of Pacifica, California, United States, approximately 7 miles (11 km) south of the city of San Francisco. It is located within a gently curving embayment with direct access via Rockaway Beach Avenue and providing easy access to Highway 1.
The Newport–Inglewood Fault is a right-lateral strike-slip fault in Southern California. The fault extends for 47 mi (76 km) from Culver City southeast through Inglewood and other coastal communities to Newport Beach at which point the fault extends east-southeast into the Pacific Ocean. The fault comes back on shore in the La Jolla area of San Diego and continues southward to downtown San Diego. In San Diego it is known as the Rose Canyon Fault. The fault can be inferred on the Earth's surface as passing along and through a line of hills extending from Signal Hill to Culver City. The fault has a slip rate of approximately 0.6 mm (0.024 in)/year and is predicted to be capable of a 6.0–7.4 magnitude earthquake on the moment magnitude scale. A 2017 study concluded that, together, the Newport–Inglewood Fault and Rose Canyon Fault could produce an earthquake of 7.3 or 7.4 magnitude.
The Franciscan Complex or Franciscan Assemblage is a geologic term for a late Mesozoic terrane of heterogeneous rocks found throughout the California Coast Ranges, and particularly on the San Francisco Peninsula. It was named by geologist Andrew Lawson, who also named the San Andreas Fault that defines the western extent of the assemblage.
Sonoma Coast State Park is a State of California property in Sonoma County consisting of public access use on lands adjoining the Pacific Ocean. This extent of beach runs from a coastal point about 4 miles (6 km) north of Jenner and continues for approximately 17 miles (27 km) to the south to terminate at Bodega Head. The property lies along State Route 1 and consists of a number of named beaches including Arched Rock Beach, Gleason Beach and Goat Rock Beach. The ecosystem consists of alternating sandy beaches and rocky shoreline, with a marine terrace extending above the entire extent with an upland California coastal prairie habitat.
The Serra Fault is the northernmost fault in a zone of northwest-striking range front thrust faults adjacent to and northeast of the San Francisco Peninsula segment of the San Andreas Fault, in eastern San Mateo County, California.
Fort Funston is a former harbor defense installation located in the southwestern corner of San Francisco. Formerly known as the Lake Merced Military Reservation, the fort is now a protected area within the Golden Gate National Recreation Area (GGNRA) and is used widely as an off-leash dog park. It was named in honor of Frederick N. Funston (1865–1917), a Major General in the United States Army with strong connections to San Francisco, and included several artillery batteries. The fort is located on Skyline Boulevard at John Muir Drive, west of Lake Merced.
The Merced Formation is a geologic formation in California, and also in Oregon and Washington state. It is named for Lake Merced, a natural lake on the western San Francisco coastline. The California portion is composed of a variety of sediments deposited on the coast of the San Francisco Bay Area in a small basin, which was split into two halves by the San Andreas Fault.
The geology of California is highly complex, with numerous mountain ranges, substantial faulting and tectonic activity, rich natural resources and a history of both ancient and comparatively recent intense geological activity. The area formed as a series of small island arcs, deep-ocean sediments and mafic oceanic crust accreted to the western edge of North America, producing a series of deep basins and high mountain ranges.
The Devil's Slide Trail is a hiking trail between Pacifica, California, and Montara, California, in the San Francisco Bay Area. The trail is a segment in the California Coastal Trail, which stretches from Oregon to Mexico.
Mussel Rock, as seen from Mori Point in Pacifica, California. (July 2006)
Mussel Rock seen from the beach of the eponymous Mussel Rock Park. (January 2021)
A pair of paragliders take flight at Mussel Rock Beach near Daly City, California.
Landslide on the cliffs near Mussel Rock as a result of the 1906 San Francisco earthquake.
Coastal bluffs facing the pacific, photographed from a trail in Mussel Rock Park.
An aerial photo of Mussel Rock.
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