Total drilling activity in Mississippi, Alabama, Florida, and Georgia, including both exploratory and development wells, decreased 25.1% from 701 wells in 1986 to 525 wells in 1987. Exploratory drilling in 1987 in the southeastern states decreased 5.1%. Of the 204 exploratory tests in 1987, 47 were successful for a 23.0% success rate. This compares to 1986's 51 successful completions of 215 tests and a 23.7% success rate.

The shallow Eocene Wilcox trend in southwestern Mississippi accounted for 31.9% of the exploratory tests. This active trend had 5 new-field discoveries in 1987 compared to 7 in 1986. The Paleozoic trend of northeastern Mississippi and northwestern Alabama had 8 new-field discoveries in 1987 compared with 16 in 1986. This trend represented 27.0% of the exploratory drilling activity in the southeast. The Jurassic trend, with 19.1% of the total exploratory effort, had 6 new-field discoveries in 1987. The Upper Cretaceous, Lower Cretaceous, and Miocene trends accounted, respectively, for 13.7%, 6.9%, and 1.5% of the total exploratory tests. Two new-field discoveries were reported in the Upper Cretaceous, 4 in the Lower Cretaceous, and 2 in the Miocene.