Oil Studies

Oil geochemistry is a fundamental component of any regional exploration and production program. It can be used to determine the number of discrete sources in a basin and their respective stratigraphic and aerial distribution, source age, lithology, depositional environment (marine, non-marine, lacustrine) and thermal maturity. Areas with overlapping petroleum systems can be identified in relation to possible oil mixing from two or more sources. Mapping source-related oil families is the first step toward understanding and predicting the lateral extent of oil fields and regional oil quality variations in different parts of the basin.

Oil samples are characterized through the use of a detailed analytical program including API Gravity, weight percent sulfur, oil composition (% saturate and aromatic hydrocarbons and polar compounds), stable carbon isotopes (whole oils, saturates and aromatics), whole oil gas chromatography (GC), and quantitative biomarker analysis of saturate and aromatic fractions by gas chromatography/mass spectrometry (GC/MS).

Selected samples have been analyzed by GC/MS/MS. Results have been used to develop an understanding of how generative petroleum systems, maturity, and biodegradation affect oil quantity and quality addressing major factors such as: (1) source facies, (2) thermal maturity, (3) distance of migration from source to trap, (4) extent and timing of biodegradation, and (5) degree of oil mixing.