Analysis of kerogen

Elemental Analysis of Kerogens (Normalized Ash-Free) Sample Information... 

Table I. Elemental analysis of "kerogens" of living plant, surface sediments and buried sediments from Abu Dhabi recent sedimentary system...

A variety of pyrolytic techniques were applied for the analysis of kerogens [19]. One of these techniques is the sealed vessel pyrolysis where the sample is heated for relatively long periods of time In a sealed vessel and the pyrolytic products analyzed off-line by conventional analytical techniques (GC, GC/MS, FTIR, etc.) [36]. Another technique is bulk flow pyrolysis in which the whole sample is pyrolysed at constant or in gradient temperature in a gas flow with on-line monitoring of the evolving volatiles [37]. This technique is closer to a thermal method of analysis than pyrolysis. 

Palmer, A. R. and Maciel, G. E. (1982). Relaxation behavior in the carbon-13 nuclear magnetic resonance spectrometric analysis of kerogen with cross-polarization and magic-angle spinning. Anal. Chem. 54, 2194-2198. 

Several related procedures for upgrading shales have been described in the literature. Generally these were developed as an adjunct to the chemical analysis of kerogen, the purpose being to reduce interference by minerals and to avoid the risk of oxidation of the organic matter by severe chemical deashing. 

The Murchison meteorite shown in Figure 6.7, like all meteorites, is named after the place from which it was recovered and in this case it is the town of Murchison, Victoria in Australia about 100 km north of Melbourne. The fall occurred in 1969 and was followed by an analysis of the chemical composition in some considerable detail. The Murchison meteorite is a carbonaceous chondrite containing about 2 per cent carbon, some as inorganic carbonates, and some as soluble compounds such as amino acids but the bulk as a macromolecular heterogeneous material referred to as kerogen. 

Combined stable isotope analysis ( C, D, N, has been used successfully in petroleum exploration (Stahl 1977 Schoell 1984 Sofer 1984). The isotopic composition of crude oil is mainly determined by the isotopic composition of its source material, more specifically, the type of kerogen and the sedimentary environment in which it has been formed and by its degree of thermal alteration (Tang et al. 2005). Other secondary effects like biodegradation, water washing, and migration distances appear to have only minor effects on its isotopic composition. 

Wolbach, W. S., and Anders, E. (1989). Elemental carbon in sediments determination and isotopic analysis in the presence of kerogen. Geochim. Cosmochim. Acta 53, 1637-1647. 

Analysis of Maturity-Related Changes in the Organic Sulfur Composition of Kerogens by Flash Pyrolysis—Gas Chromatography... 

Figure 3. DSC thermal analysis of pyrite in (A) pyrite mineral (Rico, Colorado), (B) Devonian shale kerogen, and (C) pyrite-reduced kerogen of...

Hydrous pyrolysis experiments of crude oils generated relatively large concentrations of mono-and dicarboxylic acid anions with relative abundances generally similar to those observed in sedimentary basin waters. But analysis of all of the pertinent data indicates that the major part of the organic acid anions in formation waters is probably generated by the thermal alteration of kerogen in source rocks (Kharaka et al., 1993b Lewan and Fisher, 1994). This conclusion is based on several observations ... 

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