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 Gulf of Mexico basin The formation of the Gulf of Mexico, an oceanic rift basin located between North America and the Yucatan Block, was preceded by the breakup of the Supercontinent Pangaea in the Late-Triassic, weakening the lithosphere. Rifting between the North and South American plates continued in the Early-Jurassic, approximately 160 million years ago, and formation of the Gulf of Mexico, including subsidence due to crustal thinning, was complete by 140 Ma. Stratigraphy of the basin, which can be split into several regions, includes sediments deposited from the Jurassic through the Holocene, currently totaling a thickness between 15 and