The Floridan aquifer system, composed of the Upper and Lower Floridan aquifers, is a thick sequence of Paleogene carbonate rock which spans an area of about in the southeastern United States, it underlies parts of which  state in the southern region of the United States, with part of its southern border formed by the Gulf of Mexico, and its western border is formed by the Mississippi River?
Mississippi Mississippi is a state in the southern region of the United States, with part of its southern border formed by the Gulf of Mexico. Its western border is formed by the Mississippi River.
Geography of Indiana The geography of Indiana comprises the physical features of the land and relative location of U.S. State of Indiana. Indiana is in the north-central United States and borders on Lake Michigan. Surrounding states are Michigan to the north and northeast, Illinois to the west, Kentucky to the south, and Ohio to the east. The entire southern boundary is the Ohio River.