Cordell Bank National Marine Sanctuary is a marine sanctuary located off the coast of California. It protects an area of 1286sqmi of marine wildlife. The administrative center of the sanctuary is on an offshore granite outcrop 4.5sqmi by 9.5sqmi, located on the continental shelf off of California. The outcrop is, at its closest (Point Reyes), 6mi from the sanctuary itself.Cordell Bank is one of the United States' 13 National Marine Sanctuaries that protect and preserve ocean ecosystems in the U.S. Cordell Bank is a seamount approximately 50mi northwest of San Francisco where the ocean bottom rises to within 120 feet (37 meters) of the surface. The seamount was discovered in 1853 by the U.S. Coast Survey, and named for Edward Cordell, who surveyed the area more thoroughly in 1869. It was extensively explored and described during 1978-86 by Robert Schmieder, who published a monograph about it. It has been protected as a sanctuary since 1989. The protected area encompasses 526 square miles (1347 km2) of ocean.The unique blend of ocean conditions and undersea topography creates a rich and diverse underwater ecosystem. A subsurface island rises from soft sediments covering the continental shelf. The upper pinnacles reach to within 115ft of the surface, and the average depth is 400ft. The sanctuary serves as a breeding ground for migratory marine mammals, birds, and fish. The prevailing California Current flows southward along the coast, causing an upwelling of nutrient-rich water that provided the foundation for the area's marine ecosystem.
