Chemical, molecular and isotopic differentiation of organic facies in the Tertiary lacustrine Duaringa oil shale deposit, Queensland, Australia

Stratigraphic distribution of macerals and biomarkers in the Donets Basin: Implications for paleoecology, paleoclimatology and eustacy

“…This pattern is characteristic for the presence of bacteria in the swamp (Ourisson et al, 1979) and for an oxic-type environment (Philp and Mansuy, 1997). The hopanes / steranes ratio allows estimation of the relative abundance of bacteria versus algae and terrestrial higher plants (Boreham et al, 1994;Bechtel et al, 2001). This ratio is high in our samples from coals, marine claystones and deltaic siltstones, suggesting high bacterial activity or best preservation in these environments.…”

Compound-specific carbon isotope study on the hydrocarbon biomarkers in lacustrine source rocks from Songliao Basin

“…Therefore, the ratio of hopanes to steranes (Hop/Ste) can reflect the relative contribution between bacteria and algae. The Hop/Ste values are high in K 2 n 2 , suggesting strong bacterial degradation and poor preservation of steranes due to aerobic conditions (Boreham et al, 1994). Although the relative abundance of steranes is higher in K 2 n 1 , the content of hopanes is still greater than the steranes (Fig.…”

Phylogenetic investigation of the aliphatic, non-hydrolyzable biopolymer algaenan, with a focus on green algae

“…There are numerous examples of correlation between green algae and freshwater kerogens, the Messel Shale and the Queensland oil shale for example, and we do not discount the possibility that green algae are a principal source of algaenan in these kerogens (Goth et al, 1988;Boreham et al, 1994). That stated, the majority of Paleozoic kerogens come from marine deposits…”

“…A number of freshwater kerogens show an aliphatic algaenan-like signature alongside morphological fossils of green algae known to produce algaenan (Boreham et al, 1994;de Leeuw et al, 2006;Derenne et al, 1994;Goth et al, 1988). As microanalytical techniques become more specific, the aliphatic compounds in kerogen may become more precisely linked to specific microfossils (Blokker et al, 2006), but this may be limited to freshwater environments and would not explain aliphatic kerogen from marine environments.…”