Gulf Coast of the United States Pensacola, St. Petersburg, Tampa, and increasingly, Sarasota. All are the centers of their respective metropolitan areas and contain large ports. (Baton Rouge is relatively far from the Gulf of Mexico; its port is on the Mississippi River, as is the port of New Orleans.) The Gulf Coast is made of many inlets, bays, and lagoons. The coast is also intersected by numerous rivers, the largest of which is the Mississippi River. Much of the land along the Gulf Coast is, or was, marshland. Ringing the Gulf Coast is the Gulf Coastal Plain which reaches from Southern Texas to the western
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