The occurrence and distribution of rearranged hopanes in crude oils from the Lishu Depression, Songliao Basin, China

Jiang, Lian; George, Simon C.; Zhang, Min

doi:10.1016/j.orggeochem.2017.11.007

Cited by 27 publications

(24 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar to hopanes with the αβ configuration, trisnorhopanes and C 30 diahopane are relatively thermally stable (Peters et al., ), and this contributes to an overall mature signal for the type 1 veins. For example, the C 30 diahopane/C 30 αβ hopane ratio is >1 (S18), consistent with a high thermal maturity (e.g., Jiang, George, & Zhang, ). Carbon isotope analyses of diahopanes and trisnorhopanes have previously been described showing they were derived from the same or similar organisms (Moldowan et al., ).…”

Section: Discussionmentioning

confidence: 72%

Hydrocarbon biomarkers preserved in carbonate veins of potentially Paleoproterozoic age, and implications for the early biosphere

Peters

George

2018

Geobiology

Self Cite

View full text Add to dashboard Cite

Research on the early rise of oxygenic photosynthesis and eukaryotes has recently encountered a major pitfall, as some hopane and sterane biomarkers reported in Archaean rocks are the results of contamination. Following an extensive petrological framework in the Pilbara Craton, Western Australia, oil-bearing fluid inclusions and solid bitumens were identified in replacement and hydrothermal carbonate veins cross-cutting Archaean metasedimentary rocks. The 2.55-2.63 billion years old metasedimentary rocks were found to be depleted of indigenous biomarkers. Here we show novel biomarker results from the solvent extraction of the carbonate veins. Volcanic rock blanks, outside rinses, and instrumental blanks showed no biomarkers, and the surrounding rocks were metamorphosed to a sufficiently high extent to not yield any biomarkers, but the biomarkers found in the veins are most likely indigenous. Biomarkers detected include C ααα- and αββ-steranes (pregnanes), C αββ-steranes, C tricyclic terpanes, C αβ-hopanes, C 17α-diahopane, and trisnorhopanes, which are in the range 2-180 pg/g. The extracted organic matter is highly mature, based on the biomarker configurations and calculated vitrinite reflectance that ranges from 2.4-3.0 (methylphenanthrene index), 1.4-1.9 (methyladamantane index), and 1.4-2.3 (methyldiamantane index). As the biomarkers are highly mature and the biomarker assemblages have a distinctive pattern to each vein type the likelihood of sample contamination by recent, less mature, biomarkers from a different assemblage is unlikely. The detection of steranes suggests that molecular oxygen was available when the veins were formed, possibly between 2.2 and 1.8 billion years ago, but no evidence for oxygenic photosynthesis in the form of cyanobacterial biomarkers has been found. Carbonate minerals that seem to better preserve biomarkers, such as concretions or veins, show the growing importance of new and exciting opportunities to seek biomarkers in the early Earth rock record, and potentially on other planets. Our results demonstrate for that first time that biomarkers can be found in veins cutting through highly metamorphosed Archaean rocks, and gives an insight into ancient environments.

show abstract

Section: Discussionmentioning

confidence: 72%

Hydrocarbon biomarkers preserved in carbonate veins of potentially Paleoproterozoic age, and implications for the early biosphere

Peters

George

2018

Geobiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…4 ). The early-eluting series has been known for a long time 19 , 33 – 38 , but its structure is currently undetermined, and it has only once been tentatively identified as 9,15-dimethyl-25,27-bisnorhopanes 39 . Compared with the composition of hopanes in the OMZ sediment of Unit 3, the overlying Unit 2 contains very little diahopanes or EER-H and even less C 29 Ts (Fig.…”

Section: Resultsmentioning

confidence: 99%

The aerobic diagenesis of Mesoproterozoic organic matter

Wang

Zhao

Zhang

et al. 2018

Sci Rep

View full text Add to dashboard Cite

The Xiamaling Formation in the North China Block contains a well-preserved 1400 Ma sedimentary sequence with a low degree of thermal maturity. Previous studies have confirmed the dynamic and complex nature of this evolving marine setting, including the existence of an oxygen-minimum zone, using multi-proxy approaches, including iron speciation, trace metal dynamics, and organic geochemistry. Here, we investigate the prevailing redox conditions during diagenesis via the biomarkers of rearranged hopanes from the finely laminated sediments of the organic-rich black shales in Units 2 and 3 of the Xiamaling Formation. We find that rearranged hopanes are prominent in the biomarker composition of the oxygen-minimum zone sediment, which is completely different from that of the sediment in the overlying anoxic strata. Since the transition process from hopanes to rearranged hopanes requires oxygen via oxidation at the C-l6 alkyl position of 17α(H)-hopanes, we infer that dissolved oxygen led to the transformation of hopane precursors into rearranged hopanes during the early stages of diagenesis. The use of hopanoid hydrocarbons as biomarkers of marine redox conditions has rarely been previously reported, and the hydrocarbon signatures point towards oxic bottom waters during the deposition of Unit 3 of the Xiamaling Formation, which is consistent with the earlier oxygen-minimum zone environmental interpretation of this Unit.

show abstract

“…Diagenesis under oxidising condition plays an important role in the Ts/Tm ratio, which is often low in sub-oxic environments (Moldowan et al, 1986;Peters et al, 2005), and the formation of C 30 DiaH is considered to be related to the acid-catalysis of clay minerals during the early diagenetic process (Peters et al, 2005;Baydjanova and George, 2019). The oxic environment is also considered to be favourable for the formation of C 30 DiaH (Asif et al, 2010;Jiang et al, 2018;Wang et al, 2018), and a positive correlation is often observed between the C 29 Ts and C 30 DiaH contents (Jiang et al, 2018). Additionally, thermal maturity has also been found to affect the ratios of the parameters, whereby the ratios of Ts/Tm (Chandra et al, 1994), C 29 Ts/ C 30 H, and C 30 DiaH/C 30 H (Moldowan et al, 1991;Jiang and Zhang, 2015;Fang et al, 2019) are considered to be positively correlated with thermal maturity.…”

Section: Effect Of Diagenesis On the Biomarker Distribution And Prese...mentioning

confidence: 99%

The Biomarkers in the Mesoproterozoic Organic‐rich Rocks of North China Craton: Implication for the Precursor and Preservation of Organism in the Prokaryotic Realm

Zhang

Jin

et al. 2022

Acta Geologica Sinica (Eng)

View full text Add to dashboard Cite

have suggested that the atmospheric oxygen concentration during the Mesoproterozoic was higher than previously believed (Planavsky et al., 2014), may have reached 4-8% PAL (present atmospheric levels). The trace element concentrations, organic carbon content, and biomarker data of the 1400 Ma Xiamaling (XML) Formation in the North China Craton (Zhang et al., 2016(Zhang et al., , 2017 implied that that surface ocean was aerobic during the Mesoproterozoic. This promoted the flourish of phototrophic plankton during this period (Noffke et al., 2003;Zhao et al., 2020), which promoted the formation of the Mesoproterozoic organic-rich rock. However, there are some differences between the Mesoproterozoic and Phanerozoic organic-rich rocks in sedimentary environment, organic precursor and preservation pathway of organic matter.Although some fossil evidences of eukaryotic algae had

show abstract

The occurrence and distribution of rearranged hopanes in crude oils from the Lishu Depression, Songliao Basin, China

Cited by 27 publications

References 54 publications

Hydrocarbon biomarkers preserved in carbonate veins of potentially Paleoproterozoic age, and implications for the early biosphere

Hydrocarbon biomarkers preserved in carbonate veins of potentially Paleoproterozoic age, and implications for the early biosphere

The aerobic diagenesis of Mesoproterozoic organic matter

The Biomarkers in the Mesoproterozoic Organic‐rich Rocks of North China Craton: Implication for the Precursor and Preservation of Organism in the Prokaryotic Realm

Contact Info

Product

Resources

About