What is "oil trough"

Population (2000): 218
Housing Units (2000): 105
Land area (2000): 0.191392 sq. miles (0.495702 sq. km)
Water area (2000): 0.000000 sq. miles (0.000000 sq. km)
Total area (2000): 0.191392 sq. miles (0.495702 sq. km)
FIPS code: 51410
Located within: Arkansas (AR), FIPS 05
Location: 35.629572 N, 91.461366 W
ZIP Codes (1990): 72564
Note: some ZIP codes may be omitted esp. for suburbs.
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