San francisco dating and dumping guide
As the great ice sheets began to melt, around 11,000 years ago, the sea level started to rise.
By 5000 BC the sea level rose 300 feet (90 m), filling the valley with water from the Pacific.
Despite its name, Mare Island in the northern part of the bay is a peninsula rather than an island.
San Francisco Bay is thought to represent a down-warping of the Earth's crust between the San Andreas Fault to the west and the Hayward Fault to the east, though the precise nature of this remains under study.
The first recorded European discovery of San Francisco Bay was on November 4, 1769 when Spanish explorer Gaspar de Portolà, unable to find the port of Monterey, California, continued north close to what is now Pacifica and reached the summit of the 1,200-foot-high (370 m) Sweeney Ridge, now marked as the place where he first sighted San Francisco Bay.
Portolá and his party did not realize what they had discovered, thinking they had arrived at a large arm of what is now called Drakes Bay.
The natives were displaced 5,000 years ago as the bay filled with water due to the rising sea level at the end of the ice age.
San Francisco Bay is a shallow estuary in the US state of California.
It is surrounded by a contiguous region known as the San Francisco Bay Area (often simply "the Bay Area"), and is dominated by the large cities of San Jose, San Francisco and Oakland.
It enters the bay at Alviso, a neighborhood of San Jose.
It then connects to the Pacific Ocean via the Golden Gate strait.At the time, Drakes Bay went by the name Bahia de San Francisco and thus both bodies of water became associated with the name.