The Gulf of California is an area about 59,000 square miles (153,000 square kilometers).  When Spanish explorers first saw the Gulf of California in the 16th-Century it was covered in red plankton, so the Spanish first named the gulf Mar Bermejo (the Vermilion Sea),  Some geologists hold that the gulf is structurally part of the Pacific Ocean, others claim Baja California is pulling away from the continent as it moves North along the San Andreas Fault allowing the gulf to form as its own area of water.