Mississippi Gulf Coast Mississippi Gulf Coast The Mississippi Gulf Coast, also known as the Mississippi Gulf Coast region, or simply The Coast, is the area of southern Mississippi along the Mississippi Sound along the Gulf Of Mexico. The term has traditionally referred to the three counties that lie directly on the Mississippi Sound that meet up with the Gulf of Mexico within the state: Hancock County, Harrison County, and Jackson County. The U. S. Census Bureau divided the Metropolitan Statistical Area (MSA) for the Mississippi Gulf Coast in 2003, which previously had been the three coastal counties, into two MSAs that included two
Gulf of Mexico central thin transitional and oceanic crust. Because subsidence occurred faster than sediment could fill it, the Gulf of Mexico expanded and deepened. Later, loading of the crust within the Gulf of Mexico and adjacent coastal plain by the accumulation of kilometers of sediments during the rest of the Mesozoic and all of the Cenozoic further depressed the underlying crust to its current position about 10–20 km below sea level. Particularly during the Cenozoic, thick clastic wedges built out the continental shelf along the northwestern and northern margins of the Gulf of Mexico. To the east, the stable Florida platform was