The San Pedro de Maturin diapir, a structural culmination along the Tonoro anticline, appears to be ideally situated for the entrapment of oil and gas migrating updip on the north flank of the eastern Venezuela basin. It parallels, and is located a few miles south of, the highly productive Santa Barbara-Jusepin trend; reservoir rocks, stratigraphic equivalents of productive zones along the latter trend, occur in the San Pedro de Maturin area. Seismic data suggest structural development at least during later Tertiary time. Paleoenvironmental data corrobate this and indicate that the initiation of structural growth occurred during the deposition of deeper water sediments, continuing as the basin filled in later Tertiary time. Seemingly favorable geological characteristics h ve resulted in testing of the Tonoro anticline in many locations. Numerous oil and gas shows are known but no sustained commercial production has been found.

Diapiric intrusions in the core of the Tonoro anticline may be partly or entirely responsible for the absence of commercial oil accumulations in the San Pedro de Maturin structure. The core of the structure is almost certainly diapiric, as shown by the anomalous relationships of Foraminifera, the presence of high pressure, low volume pockets of hydrocarbons, the presence of heaving slickensided shales, and the limited lateral extent of the La Pica sands in the core of the structure.

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