Statistical studies based on the mapping of paleoecologic zones, sandstone conditions, and production in offshore Louisiana indicate a positive correlation among these parameters. Oil and gas production for given depth is associated with a narrow range of preferred environments of deposition and sandstone development. For example, in the depth range 10,000-12,000 ft in the eastern offshore area (Ship Shoal through Main Pass), about 70% of all oil wells are completed where the section contains 10-30% sandstone and is in the inner neritic environment.

An IBM 1130 computer with attached Calcomp plotter was used to prepare (1) structure and environment maps of various biostratigraphic surfaces, (2) environment maps of the interval between biostratigraphic surfaces, and (3) environment maps at constant depth slices. To aid in statistical comparisons, the following maps were constructed in 2,000-ft-thick depth intervals: (1) average weighted environment; (2) sand percentage, net sand, sandstone-shale ratio, and number of discrete sandstones; and (3) oil and gas completions.

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