San Jose Facts

Most of California, the exception being a south eastern piece, is made of recycled sea floor scraped off as the ocean floor subducted beneath the North American Tectonic Plate. That means that all of this rock we are standing on in San José and the surrounding area was actually ocean floor millions of years ago. It has since piled on to what is now the USA like the crinkled butter that builds up on the butter knife that scrapes across it. Millions of years ago the North America coastline was way further east of what is now the California coast; before so much north-east moving oceanic crust went under the westward moving North American Plate.

All of the dark grey area in the above map is ocean floor that had been scraped up and added to the land that is now the US and Mexico during the last 200 million years.

Source: Rough-Hewn Land, book by Keith Meldahl, 2011, page 9.