The Tupungato oil field is 50 kilometers south-southwest of the city of Mendoza in west-central Argentina, in an area just east of the foothills of the Andes Mountains where the principal tectonic features are overthrust faults of late Tertiary age. The surface structure, discovered in 1932, is a closed dome with faulted west flank. The discovery well was completed in 1934 at a depth of 250 meters. Seventeen shallow wells were drilled to depths averaging 450 meters, most of which produced oil with strong flows of salt water from fractures in the upper part of the Tertiary (Pliocene) section. The discovery well of the Victor zone of Upper Triassic age was completed in 1938 at a depth of 1,796 meters. The peak production from this zone, 9,400 barrels per day, was reached in October, 1941, after the completion of 17 productive wells.

The major part of the difference between the structure of the surface and that of the various horizons which can be identified in well samples is believed by the writer to be due to the presence of low-angle thrust faults which cause variations in the thickness of the Tertiary section in different parts of the field, but this can not be definitely proved. There is some indication of the existence of a gentle fold prior to the deposition of the Tertiary.

The oil of the Victor zone occurs in fractures and pores of the upper part of a thick series of volcanic tuffs, but is believed to be produced almost entirely from the fractures. It is of the same type, with a high paraffine content, as that produced from lower stratigraphic levels in the other oil fields of northern Mendoza.

A deeper zone, probably of little importance, was opened by the completion of T 48 in July, 1942, at 2,563 meters. In December, 1942, well T 50 reached the zone which is productive in the Cacheuta and Lunlunta fields, finding a higher-grade oil under high pressure but with small volume. At that time, it was the deepest well in Argentina, 2,921 meters. The importance of this discovery must be determined by future drilling.

The Yacimientos Petroliferos Fiscales is the sole operator.