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
Title: Floridan aquifer
Passage: 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 the entire state of Florida and parts of Alabama, Georgia, Mississippi, and South Carolina.
Title: Gerhardminnebron
Passage: Gerhardminnebron is a natural karst spring located a few kilometers east of Ventersdorp in South Africa and draining into the Wonderfonteinspruit and Mooi River, which in turn flows into the Vaal River.  It yields some 60 000 – 80 000 cubic meters of water per day, and is affected by exploitation and pollution by the gold mining industry in the region, deep–level gold mining having markedly impacted on the dolomitic aquifers.  This spring is located in dolomitic rock that is part of the larger Boskop–Turffontein dolomite compartment in the Transvaal Basin.  Dolomite or dolostone is a sedimentary carbonate rock, a swath of which runs parallel to the Magaliesberg, and has a tendency to form large underground lakes and reservoirs.
Title: Mississippi
Passage: 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.
Mississippi Floridan aquifer