Alkylbiphenyls and alkyldiphenylmethanes as indicators of petroleum biodegradation

A new biodegradation prediction model specific to petroleum hydrocarbons

“…Only two biphenyl compounds, biphenyl and 4‐methylbiphenyl, are present within the original data set. The petroleum geochemistry literature suggests that the rate of biodegradation is biphenyl > methylbiphenyl > dimethylbiphenyl > trimethylbiphenyl [54], with the biphenyls not affected until most of the n‐alkane fraction is biodegraded but before the isoprenoids are significantly degraded. It has been reported in a reservoir study that trimethylbiphenyls can be detected in oils considered to be severely biodegraded (level 7) [54], suggesting that the model may work only for biphenyls with one or two substituents.…”

Investigation of polycyclic aromatic hydrocarbons (PAHs) and cyclic terpenoid biomarkers in the sediments of fishing harbors in Taiwan

“…Generated PAHs then can be transported into the environment by wet or dry deposition as well as by daily human operations. The distribution of PAHs and petroleum biomarker compounds in the marine sediments of rivers, estuaries, coastlines and sea beds have been commonly investigated (Boonyatumanond et al, 2006;Gong et al, 2014;Grice et al, 2009;Keshavarzifard et al, 2015;Page et al, 1999;Pauzi Zakaria et al, 2001;da Silva and Bicego, 2010;Tolosa et al, 2004;Trolio et al, 1999;Wang et al, 2011). Researchers have reported that the investigated PAHs in the marine sediments and the analyzed concentrations (in lg/kg) were up to 8399, 51,261, 434 and 11,557 lk/kg in the coastal areas of Thailand, along the river mouths close to Kaohsiung harbor (Taiwan), the coasts of Sicily (Italy) and the Gulf of Gela (Italy), respectively (Boonyatumanond et al, 2006;Dong et al, 2012;Frenna et al, 2013;Orecchio et al, 2010).…”

Diamondoids and biomarkers: as a tool to better define the effects of thermal cracking and microbial oxidation on oils/condensates from reservoirs of the Upper Indus Basin, Pakistan

“…More specifically, it is the relative susceptibility of different compound classes (e.g., n-alkanes, branched alkanes, alkylated monocyclic alkanes, bicyclic terpanes, steranes, diasteranes, hopanes, alkylated benzenes, alkylated biphenyls, polycyclic aromatic hydrocarbons) to microbial oxidation that in part, collectively determines such differences in bulk petroleum stability (Illich et al 1977;Seifert and Moldowan 1979;Alexander et al 1983;Connan 1984;Gough and Rowland 1990;Peters and Moldowan 1991;Armanios et al 1992;Bennett et al 2006;Trolio et al 1999). Diamondoids are of particular importance in petroleum geochemistry since they can provide valuable information toward achieving a better understanding of petroleum systems in sedimentary basins.…”

“…Diamondoids are of particular importance in petroleum geochemistry since they can provide valuable information toward achieving a better understanding of petroleum systems in sedimentary basins. Unfortunately, little information is available about the implications of diamondoid signatures in petroleum reservoirs Trolio et al 1999;Grice et al 2000, Zhibin et al 2007.…”

“…Nevertheless, most ''normal'' oils with low maturity and no cracking typically have high concentrations of biomarkers and extremely low concentrations of diamondoids (Zhibin et al 2007). Conversely, in highly cracked oils, concentrations of diamondoids are generally very high and biomarkers are extremely low or in some cases totally absent (Trolio et al 1999). This suggests that any oil with high abundances of both diamondoids and biomarkers should reflect a mixture of low maturity oil and highly cracked sources (Zhibin et al 2007).…”