|Ventura, G.T., Raghurman, B., Nelson R.K., Mullins, O.C., and Reddy, C.M., |
Compound class oil fingerprinting techniques using comprehensive two-dimensional gas chromatography (GC×GC). , Organic Geochemistry 41(9), 1026-1035., 2010
Detn. of connectivity is of primary importance in petroleum reservoir characterization. Lack of connectivity can occur when the communication between two oil-producing zones is restricted. This subsurface condition is referred to as reservoir compartmentalization. Recognition of compartmentalization is often achieved by establishing whether two or more oils have the same mol. compn. and hence are consistent with an equil. condition within a reservoir. Gas chromatog. (GC) is one std. technique used to measure oil similarity. However, it is severely limited in the no. of compds. that can be resolved in fluids as complex as oil. Comprehensive two-dimensional gas chromatog. (GC×GC) greatly expands the resoln. of compds. in such complex mixts. In this study, GC×GC was used to compare the mol. compns. of two pairs of oil samples collected directly at depth within a reservoir drill hole. The first pair was sequentially sampled at the same depth and should represent the same oil. The second pair was collected from two different wells that were intersected by a permeable sedimentary horizon. The four samples were compared to each other and to a control sample using a novel comparative technique involving the sepn. of oil compns. into compd. classes that are compared across a series of retention index ranges. These techniques were used to det. the compositional similarity of two or more oils, providing a more complete compositional comparison than possible with gas chromatog.-mass spectrometry (GC-MS) and GC-flame ionization detection (GC-FID).