What flatlands circle the northern and western coastline of the gulf of mexico?

The flatlands of the 'Gulf Coastal Plain' circle the 'northern and western coastline' of the Gulf of Mexico.

Explanation:

The Gulf of Mexico is clearly circled by the coasts of US and Mexico on its closed side. In both countries, this continued coastal line circling the gulf and the adjacent region that stretch a little deeper into the interiors of both the countries are collectively called the 'Gulf Coastal Plain'. It comprises of the coasts of eastern and the upper-southern Mexico, southeastern Texas, western Florida, and southern Louisiana. The region is called so owing to the absence of any naturally occurring geographical features of varied elevation.

The Gulf Coastal Plain.

The Gulf Coastal Plain is a lowland in North America located in the southern United States and northeastern Mexico and bordering the Gulf Coast. In the northeast it passes into the Atlantic Lowland, in the north it borders on the Central Plains, the Appalachian and Ouachita Mountains.

It is crossed by the valleys of major rivers - the Mississippi, Alabama, Brazos and Rio Grande. There are many lakes along the coast, and its climate varies from subtropical in the north to tropical in the south.

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Cause of he different elevations  hope this ?

Answerprediction;