Any application of controversial theories concerning the origin, migration, and alteration of petroleum must be presented as a hypothesis that satisfies known prerequisites, including those demanded by geologic history. Permian shelf-edge carbonates, both reef and nonreef, were deposited near sea level, and time horizons in them can be used as paleolevels in determining the time, direction, and magnitude of tilts which affected the migration of petroleum in the Permian Basin of West Texas and southeastern New Mexico. The geologic prerequisites assumed to be necessary for secondary migration are (1) sufficient depth of burial, (2) carrier beds, and (3) adequate regional tilt. These prerequisites to secondary migration within the Abo formation were best satisfied during the Permian Period.

The API gravity of crudes found in the studied Permian formations forms regional patterns which are assumed to reflect secondary migration. The Abo oil-gravity pattern differs from the overlying Grayburg pattern. This is interpreted to mean that secondary migration within the Abo had ceased prior to secondary migration within the Grayburg. The Grayburg migration was caused by post-Grayburg tilt; thus secondary migration within the Abo had ceased by the end of Grayburg time.

Levorsen's technique, which involves the study of reservoir pressures and gas saturations as related to depth of burial, was used to estimate the time of final oil accumulation in three fields in southeastern New Mexico. The Vacuum field was found to be an example of accumulation due to secondary migration within the late Leonardian and early Guadalupian Epoch of the Permian. Accumulation during secondary migration probably occurred at the Lovington field also, but a study of trap capacity and an application of Levorsen's technique to both the Abo and overlying San Andres reservoirs indicate that final accumulation did not occur until the late Triassic. The accumulation at the Empire field occurred during the late Tertiary and early Quaternary after regional eastward tilt resulted in he establishment of a favorable hydrodynamic system, and after the erosion of Pliocene, Triassic, and upper Permian strata.

Secondary migration within the Abo occurred during the Permian, and two detectable episodes of remigration occurred during and after times of regional unconformity. The stratigraphic sequence of late Permian strata overlain by late Triassic strata, overlain by late Tertiary strata, dates these times of unconformity.