Cretaceous Debris Reservoirs, Poza Rica Field, Veracruz, Mexico

The giant Poza Rica Field was the backbone of Mexican oil production from shortly after its discovery in 1930 until eclipsed by spectacular new discoveries in the Isthmus of Tehuantepec and Campeche Shelf in the 1970s. Poza Rica (Fig. 28-1) is located in northeastern Veracruz state, Mexico, 20 miles (30 km) southwest of the Gulf of Mexico, 120 miles (190 km) south of Tampico, and 135 miles (215 km) northeast of Mexico City. The field was discovered in May 1930, with the drilling of the Poza Rica #2 well, which produced from the gas cap at 6714 feet (2047 m) subsea for about 3 years (Salas, 1949). Initial drilling was based on a torsion balance survey in 1923 that showed a gravity high along the Rio Cazones about 2.5 miles (4 km) west of the village of Poza Rica. Mapping of the outcropping Oligocene and Miocene rocks gave a hint of structure at depth. An additional gravity survey in 1930, followed by a seismic survey, led to recognition of a broad domal structure and additional drilling that penetrated the oil reservoir in November 1932 (Salas, 1949).