The Gulf of Mexico consists of several ecological and geologic provinces, chief of which are the coastal zone, the continental shelf, the continental slope, and the abyssal plain. On March 13, 2009, the CLCS accepted Mexico's arguments for extending its continental shelf up to 350 nautical miles (650km; 400mi) into the Western Polygon. On July 15, 2010, BP announced that the leak stopped for the first time in 88 days. On January 25, 1699, Iberville reached Santa Rosa Island in front of Pensacola founded by the Spanish; he sailed from there to Mobile Bay and explored Massacre Island, later renamed Dauphin Island. Eakins, 2009. Gulf of Mexico Activities | Bureau of Ocean Energy Management 1 Aug 1999. Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. This low error meant that data from these depths would reveal the finest-resolution regional deepwater bathymetry ever created. The shipwreck, whose real identity remains a mystery, lay forgotten at the bottom of the sea until it was discovered in 2002 by an oilfield inspection crew working for the Okeanos Gas Gathering Company (OGGC). The thickness of the isothermal layer (a surface layer of water of constant temperature) varies from about 3 to more than 500 feet (1 to more than 150 metres), depending on seasonal and local conditions as well as on location. The Gulf of Mexico borders the southeastern coast of North America. North West European Waters. They then compared the resulting depth grid with more than 300 well penetrations across the GOM to determine the time-depth conversion error, which averaged 1.3% of water depth. The most popular bathymetry map of the northern Gulf of Mexico has been the version generated in the 1990s by the National Oceanic and Atmospheric Administration (NOAA), the National Geophysical Data Center (NGDC), and Texas A&Ms Gulf of Mexico Coastal Ocean Observing System (GCOOS). The highest average error, 5%, occurs in water depths shallower than 150 meters because of the nature of conventional seismic acquisition in shallow water and the high variability of temperature and salinity in shallow water, which affect the velocity of sound in water. In part artificial, the waterway consists of a channel paralleling the coast behind barrier beaches, the channel being linked by a series of canals. The large Chlorophyll-a values in red are associated with brackish waters from river origins. They created a mosaic of more than 100 of their highest-quality bathymetry maps, spanning water depths of 40 to 3379 meters and interpreted on seismic surveys originally shot by 15 different geophysical companies.