Stable Isotope Geochemistry of the Organic Elements within Shales and Crude Oils: A Comprehensive Review

Abstract

Over time, stable isotopes have proven to be a useful tool in petroleum geochemistry. However, there is currently insufficient literature on stable isotope geochemistry of the organic elements within shales and crude oils in many petroleum systems around the world. As a result, this paper critically reviews the early and recent trends in stable isotope geochemistry of organic elements in shales and crude oils. The bulk and compound-specific stable isotopes of H, C, and S, as well as their uses as source facies, depositional environments, thermal maturity, geological age, and oil–oil and oil–source rock correlation studies, are all taken into account. The applications of the stable isotopes of H and C in gas exploration are also discussed. Then, the experimental and instrumental approaches to the stable isotopes of H, C, and S, are discussed.

Fingerprinting Organofluorine Molecules via Position-Specific Isotope Analysis

“…The organofluorine molecules examined in this study are synthetic, and thus built from precursors that are likely derived from petroleum or natural gas. Petroleum typically has a carbon isotope abundance (δ 13 C) of −23 to −31‰, 70 but can vary significantly depending upon the source. 70,71 Natural gas is usually lighter in its carbon isotope abundance, with δ 13 C of −40 to −65‰ being typical.…”

“…Petroleum typically has a carbon isotope abundance (δ 13 C) of −23 to −31‰, 70 but can vary significantly depending upon the source. 70,71 Natural gas is usually lighter in its carbon isotope abundance, with δ 13 C of −40 to −65‰ being typical. 72 The differences that we observe in the intramolecular 13 C/ 12 C isotope distribution in the various organofluorine samples may be rooted in the isotopic composition of the precursor molecules used in synthesis of each compound.…”

Special Issue “Applications of Stable Isotope Analysis”

“…This Special Issue aims to provide an updated view and highlight the advances in the application of stable isotope analysis (SIA) in the different fields of chemistry. It includes five research articles and two review papers dealing with the use of this technique in geochemical [ 2 , 3 ], archaeological [ 4 , 5 , 6 ], environmental [ 7 ], and food [ 4 , 8 ] studies.…”

“…Finally, the works by Ogbesejana et al [ 2 ] and Nyamgerel et al [ 3 ] reviewed different aspects related to the applications of geochemistry, due to the recurrent use of SIA in this discipline. Ogbesejana et al [ 2 ] reviewed the SIA of organic elements within shales and crude oils.…”

“…Finally, the works by Ogbesejana et al [ 2 ] and Nyamgerel et al [ 3 ] reviewed different aspects related to the applications of geochemistry, due to the recurrent use of SIA in this discipline. Ogbesejana et al [ 2 ] reviewed the SIA of organic elements within shales and crude oils. Due to the usefulness of this kind of analysis in petroleum geochemistry, the bulk and CSIA of S, C, and H as well as their relationships with the source, depositional environments, thermal maturity, geological age, oil–oil and oil–source rock correlation, and gas exploration were the subject of the study.…”