Reservoir compartmentalization assessment by using FTIR spectroscopy A. Permanyer a, ⁎ , C. Rebufa b , J. Kister b a Dept. Geoquímica, Petrologia i Prospecció Geològica, Universitat de Barcelona, Martí i Franquès, s/n, 08028—Barcelona, Catalonia, Spain b Université d'Aix—Marseille III, Faculté des Sciences et Techniques de St. Jérôme, CNRS UMR 6171, Laboratoire de Géochimie Organique Analytique et Environnement (GOAE), Case 561, 13397 Marseille Cedex 20, France Received 16 February 2005; accepted 5 September 2005 Abstract Reservoir geochemistry has traditionally used the gas chromatographic fingerprinting method and star diagrams to provide evidence of petroleum reservoir compartmentalization. Recently alternative techniques such as Fourier Transform Infra Red (FTIR) spectroscopy have been postulated to aid the evaluation of reservoir compartmentalization, and to characterize the geochemical evolution of oils from individual reservoirs. FTIR spectroscopy was applied successfully in the Tarragona Basin, Offshore N.E. Spain, validating the method to identify oils from different reservoirs. Moreover the method was successfully applied to provide evidence of compositional differences in oils from a faulted reservoir (El Furrial field, Venezuela), in which GC fingerprints failed to differentiate the oils. FTIR spectroscopy therefore, proves to be a complementary tool for reservoir compartmentalization studies. © 2007 Elsevier B.V. All rights reserved. Keywords: Reservoir geochemistry; Compartmentalization; Fourier Transform Infra Red Spectroscopy; FTIR; Gas chromatography; Tarragona Basin; El Furrial oil field 1. Introduction In recent years, the application of organic geochem- istry to assessment of compartmentalization has been well documented. Most of the literature is focused on the characterization of crude oils for addressing issues such as vertical and lateral reservoir discontinuities (Slentz, 1981; Kaufman et al., 1990; Hwang et al., 1994; Hwang and Baskin, 1994; Halpern, 1995; Magnier and Trindade, 1999). The small differences in the structural and functional composition of crude oils that may occur in the reservoirs may be used to identify possible compart- mentalisation. Heterogeneities in crude oil fingerprints are, therefore, useful for identification of reservoir discontinuities. To this end, gas chromatographic fingerprints of oils are extensively used for evaluation of reservoir com- partmentalization. Star diagrams using selected inter-n- alkanes peak ratios identifiable in a whole oil chromato- gram are often utilized as are aromatic hydrocarbons (Ganz et al., 1997). However, differences in oils cannot always be deduced by utilizing only chromatographic fingerprints. Thus, a Journal of Petroleum Science and Engineering 58 (2007) 464 – 471 www.elsevier.com/locate/petrol ⁎ Corresponding author. Tel.: +34 93 4021416. E-mail address: albert.permanyer@ub.edu (A. Permanyer). 0920-4105/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.petrol.2005.09.009