The Louisiana Gulf Coast includes the 38 southern parishes of Louisiana and the 16 continental-shelf areas offshore. Oil and gas are produced from sediments ranging in age from Cretaceous to Pleistocene.

There were 2,570 development and exploratory wells drilled in 1966, 12% fewer than in 1965. Of the 875 exploratory wells, 23% were successful.

Of the 44 new-field discoveries (21 onshore and 23 offshore), the most important are: Block 133 field, West Delta Area; Coon Point field, Ship Shoal Area; and St. Amelia field, St. James Parish. The most significant of the 185 new pools and extensions include Block 6 field, Main Pass Area; Block 16 field, Grand Isle Area; Block 58 field, West Delta Area; Fordoche field, Pointe Coupee Parish; Bayou Hebert field, Vermilion Parish; and Garden City field, St. Mary Parish.

Geophysical and drilling activity declined slightly from the previous year. Lease activity for the total area compared favorably with 1965.