Gulf of Mexico Gulf of Mexico The Gulf of Mexico () is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. The U.S. states of Texas, Louisiana, Mississippi, Alabama, and Florida border the Gulf on the north, which are often referred to as the "Third Coast", in comparison with the U.S. Atlantic and Pacific coasts. The Gulf of Mexico formed approximately 300 million years
Gulf of Mexico basin evaporite sediments deposited after the opening of the Gulf of Mexico has become the Florida Platform. Salt in the Gulf of Mexico can be divided into two main regions: the Northern Gulf of Mexico salt basin and the Campeche salt basin; interpreted to have formed simultaneously. Also referred to as the Louann and the Yucatan Salt basins. Salt deposition in the Gulf of Mexico is poorly dated; the Louann Salt has no index fossils and the age is based on the ages of formations below and above. Salt deposition began in the Jurassic after the first rotation of the Yucatan