STUDY OF THE ORGANIC GEOCHEMICAL PARAMETERS OF THE PIMIENTA FORMATION AND ITS IMPLICATION AS A GAS AND OIL GENERATING ROCK.

Abstract

In order to determine the quality of the Pimienta Formation in the state of Veracruz as a hydrocarbon-generating rock and its role as an unconventional reservoir (shale gas/oil), the average values of TOC, Tmax, S2/S3 and IP of fourteen wells located in the northwestern portion of the state of Veracruz were analyzed.  in the range of 1590 m to 3272 m depth. Due to the TOC content (1.14 to 2.79%), in some wells present in the study area, the Pimienta Formation can be classified as a hydrocarbon generator, with a fair to excellent quality. The Tmax data (423°C to 457°C) place the source rock in an early to late phase of thermal maturity. The producing potential (PP) of the area is weak to medium and the calculation of the type of hydrocarbon generated (S2/S3) indicates the presence of oil and gas in the formation, and the existence of oil may occur at depths from 2100 m in the studied area, if the hydrogen index (IH) vs. oxygen index (IO) are observed.  Its evolution indicates that the predominant kerogen is a mixture formed mainly of types III and II, which can be interpreted as the precursors of gas and oil.