Los Angeles: A Megacity of 12 Million People Living Over the World’s Richest Oil Field

Most organic source material for oil and gas was deposited during the middle-to-late Paleozoic and the middle-to-late Mesozoic.By contrast, the source rock for the Los Angeles Basin petroleum is unusually young.The Miocene, organic-rich Monterey Formation was deposited between ~18-5 Ma in offshore basins at water depths between 500 and 2300 m.These basins formed as California evolved from a subduction to a transform plate margin (Behl, 1999), giving birth to the San Andreas Fault.