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The formation and composition of natural gas generated from the Duvernay Formation was simulated by heating immature kerogens in a closed system (MSSV pyrolysis) at three different heating rates (0.1, 0.7 and 5.0 °C/min). It was not possible to evaluate reasonable kinetic parameters for the formation of single compounds using accepted protocols, because even at the highest pyrolysis temperatures there is still methane formation, while ethane and propane formations show a significant heating rate dependency of their maximum yields. To circumvent these obstacles a new method was developed utilising the following observations: (1) bulk gas fraction C 1−5 does not show any heating rate dependency of its maximum yield, (2) omitting either ethane or propane, the generation of both of which are heating rate dependent, from the total gas fraction (which gives the C 1−5 − C 2 as well as C 1−5 − C 3 ) resulted in yields which were not heating rate-dependent. Thus, the kinetic evaluation for these fractions is valid and could be used to predict the formation of the bulk fractions for geological heating rates. By calculating the difference of C 1−5 and C 2−5 , C 1−5 − C 2 as well as C 1−5 − C 3 , it was possible to predict the temperatures of methane, ethane and propane formation under geological conditions. Methane was predicted to represent 60–70 mol% of the natural gas formed from the Duvernay Formation with an onset temperature of 120 °C for a geological heating rate of 3 °C/my. Ethane and propane were predicted to represent 20 and 10 mol% of the Duvernay gas, respectively. The onset of ethane and propane formations was predicted to take place at 130 °C. Interestingly, using this concept the composition of gas formed from the Duvernay Formation can be predicted very well and fits to reservoired Duvernay gas in petroleum accumulations along the Rimbey–Leduc–Meadowbrook Reef System, which was formed during the main phase of petroleum formation.

The perchloroethylene (PCE) sorption distribution coefficient ( K d , measured at 40–100 μg/l solution concentration in batch experiments) ranged from 4.0 to 134 l/kg over the sampled thickness (1.0–6.0 m depth) of a moderately-low organic carbon (0.002–0.005), fractured and weathered diamict (poorly sorted, glacially deposited) aquitard. The organic carbon-normalized K d ( K oc ) for deeper, unoxidized (reduced) samples from this deposit (log K oc =4.4–4.59) were generally consistent with the kerogen in the underlying Devonian-age shale (log K oc =4.57), a likely source rock for these sediments. The similarities between these samples suggest that the sorption capacity of the kerogen was minimally altered during transport and deposition, and that humic substances were not co-deposited with the kerogen in the glacially-deposited sediments. The K oc within the diamict was correlated to the oxidation state of the organic matter, characterized by the H/O ratio through elemental analysis. The K oc for more oxidized samples from shallower depth samples (log K oc =3.35–3.65) were approximately an order of magnitude less than those determined for the reduced samples. The K oc for 1.5- to 2.5-cm thick oxidation haloes surrounding fractures and characterized by visible Fe-oxidation, were approximately 20–30% lower than the adjacent unaltered matrix samples. The linear trend observed between log K oc and log H/O is similar to, but steeper than, the relation reported previously, which represents increasing sorption magnitude with increasing diagenesis in coal and shale samples. The spatial distribution of the K oc within this aquitard, in concert with qualitative geologic observations, suggests that oxidative weathering of the native kerogen exerts an important control on hydrophobic organic compound sorption.

Kerogens isolated from four rocks of Ordovician age from North America have been analysed by combined pyrolysis-gas chromatography-mass spectrometry to compare and contrast the type and distribution of sulphur-containing compounds and aromatic and aliphatic hydrocarbons present in the pyrolysates. When pyrolysed, all of the kerogens released several series of heterocyclic sulphur compounds including alkylthiophenes, alkylthiolanes, alkylthianes and alkylbenzothiophenes together with n -alkanes, n -alklenes and alkylcyclohexanes as well as alkyl-substituted benzenes and naphthalenes. One of the kerogens, isolated from the Guttenberg oil rock, consisted predominantly of the alga Gloeocapsomorpha prisca , which produced sulphur compounds and hydrocarbons with fingerprint pyrograms that were different from those of the other three kerogens. The data provide prima facie evidence that these distributions may act as pseudo “biological markers” for this species of alga, namely that unsaturated kerogen moieties available for the uptake of sulphur, or which can cyclise to form hydrocarbons, distinguish Gloeocapsomorpha prisca from the contributing organisms of the other kerogens analysed.