Oil Geochemistry As Exploration Tool: ABSTRACT

Abstract

Oils represent a final product of physical and chemical processes within a basin. As such, they contain compositional attributes that can be utilized to describe the conditions through which they evolved. Data obtained from high-resolution gas-liquid chromatographic and mass-spectrometric analyses of whole oils substantially reduce exploration risk by providing information concerning fluid characteristics. Some of the information that can be deduced from the analysis of oils is: the number of sources, alteration during migration or after accumulation, and mixing of oils derived from one or more sources. Oil geochemistry assists in evaluating the probable numbers of potential reservoir zones, the possibility of encountering cross-stratigraphically migrated oils, and the robable value of potentially exploitable reservoirs. The effective use of oil geochemistry depends on the availability of accurate and precise analytic data. Some significant applications involve whole-oil, gas-liquid chromatography, distribution of sulfur-bearing organics, distillation curves, and mass-spectral data. The efficient treatment of data obtained from oil analyses is central to the problem of producing a succinct interpretive statement meaningful to management. Data reduction and manipulation techniques are also important. The occurrence of oils within a region is the ultimate demonstration of the presence of source beds and the dynamics of migration and accumulation. Oils should be exploited to obtain a view of the potential of a region because, in nonfrontier areas, samples are often available before major exploration commitments are required. End_of_Article - Last_Page 472------------