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The goal of the present Thesis is to investigate a suite of oils from Central Arabia and inspect them for the presence of conventional hopane and sterane biomakers, as well as non-conventional markers such as phenanthrene and its methylated isomers. Paleozoic and Jurassic oils and condensates from several fields from Central Arabia as well as the Eastern Province (for comparison) were collected. Bulk properties, such as API gravity, percent sulfur, and nitrogen content of these oils were determined. The oils and condensates were then fractionated into their major compound classes: saturates, aromatics, polars, and asphaltenes. The saturate and aromatic fractions were analyzed by gas chromatography (GC) as well as by gas chromatography-mass spectrometry (GC/MS). Bulk properties, pristane/phytane ratios, MPR, and %Rc values showed that Paleozoic oils from Central Arabia differ significantly from Jurassic oils from the Eastern Province. Central Arabian Paleozoic oils and condensates are: high-API-gravity, exceedingly low sulfur, low nitrogen and low metals crude oils. They have pristane/phytane ratios that are greater than one indicating dysoxic conditions at the time of deposition of their source rocks. Their MPR and %Rc values are indicative of differences in timing of generation from the source rock as well as in maturity and, perhaps most significantly, indicative of post-generative alteration such as, water washing. Eastern Province Jurassic oils are: medium-gravity, high sulfur, high nitrogen crude oils. They have pristane/phytane ratios that are less than one indicating highly reducing conditions at the time of source rock deposition. Their MPR and %Rc values are indicative of generation from a source rock that was at peak oil maturity (VRe usd\approxusd 0.80 to 1.0%). (Abstract shortened by UMI.)
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