Lower Arkansas
South Arkansas lies within the southern most portions of Arkansas Gulf Coastal Plain and Delta regions. It encompasses the lower 15 counties of the state.
In the 1920s, nationwide attention focused on South Arkansas when the Smackover Field was ranked first among the nation's oil fields. For five months in 1925, the 40-square-mile (100 km2) Smackover Field was the focal point of one of the wildest mineral booms in North America. Today, south Arkansas's oil fields produce petroleum throughout a 10-county area.
Columbia and Union counties also stretch over one of the largest Brine reserves in the world. Bromine is derived from brine, or saltwater, and local companies play an international role in the commercialization of bromine and its many applications.
Coordinates: 33°12′N 92°42′W / 33.2°N 92.7°W
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