Stratigraphic interpretation of gamma-ray logs and identification of ammonites from the Kix 1A and Pich 1 wells confirm the existence of the Sinan-Mison syncline in the Campeche Shelf, southern Gulf of Mexico. The structural configuration of the syncline was determined once the contact between the Edzna-Akal formations was established at the Jurassic–Cretaceous boundary on the basis of depth data from wells in the region.

Subsurface data (1) yield new insights into the stratigraphic and structural position of the contact between the Edzna and Akal formations, which have great petroleum potential and (2) validate the certainty of the methodology applied.

The systematic study of specimens Aspidostephanus sp., Cuyaniceras sp., and cf. Corongoceras sp. from the Kix 1A and Pich 1 wells are characteristic of the Tithonian and the Berriasian. This is the first known occurrence of Berriasian ammonites in the subsurface of southern Mexico.