Accelerated Solvent Extractor Accelerated Solvent Extractor

The ASE extracts solid and semisolid samples with liquid solvents at elevated temperatures and pressures for increased efficiency.

Gas Chromatographs Gas Chromatographs

Gas chromatography is the main technique we use to separate out the individual components of very complex mixtures.

High Resolution Mass Spectrometer High Resolution Mass Spectrometer

The autospec combines the separating power of gas chromatography with the sensitivity of mass spectrometric detection.

Isotope Ratio Mass Spectrometer Isotope Ratio Mass Spectrometer

Stable isotope analysis for many different types of substances—organic matter, carbonates, gases and individual organic compounds.

Agilent 6000 Series HPLC-MS Agilent 6000 Series HPLC-MS

High Pressure Liquid Chromatography separates compounds, a Quadrupole Time-of-Flight mass spectrometer identifies lipids.

Lab Tour Lab Tour

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Common steranes, hopanes and other polycyclic terpanes in the molecular fossil record and their paleobiological interpretation

Biomarker Biological and/or environmental interpretation References
C30-hopanes diverse bacterial lineages, few eukaryotic species (e.g. some cryptogams, ferns, mosses, lichens, filamentous fungi, protists) Rohmer et al., 1984
extended C31 to C35 hopanes (a.k.a. homohopanes) diagnostic for Bacteria, biosynthesis appears to be restricted to lineages that are not strictly anaerobic (with a possible exception (Thiel et al., 2003) Ourisson and Albrecht, 1992, Rohmer et al., 1984
extended C32 to C36 2a-methylhopanes diagnostic for cyanobacteria and prochlorophytes Bisseret et al., 1985, Summons et al., 1999
extended C32 to C36 3b-methylhopanes diagnostic for some microaerophilic proteobacteria (certain methylotrophs, methanotrophs, acetic acid bacteria) Zundel and Rohmer, 1985a, Zundel and Rohmer, 1985b, Zundel and Rohmer, 1985c, Summons and Jahnke, 1992
28,30-dinorhopane, 25,28,30-trinorhopane (TNH) often prominent in sediments from euxinic environments Grantham et al., 1980, Peters and Moldowan, 1993
24-norcholestane (C26) possible diatom origin, high concentrations relative to 27-norcholestane indicate Cretaceous or younger crude oil Holba et al., 1998a, Holba et al., 1998b
Cholestane in aquatic sources probably almost exclusively derived from diverse eukaryotes Volkman, 2003
in organic matter from terrestrial sources (e.g. paleosols) input from soil bacteria of the order Mxyococcales conceivable Bode et al., 2003, Kohl et al., 1983
Ergostane, stigmastane exclusively eukaryotic, but usually no distinct sources discernible Volkman, 2003
24-n-propylcholestane pelagophyte algae, a biomarker for marine conditions with few exceptions Moldowan et al., 1990
24-isopropylcholestane sponges and possibly the sponge-related stromatoporoids McCaffrey et al., 1994b
2- and 3-alkylsteranes ubiquitous in bitumens of all ages, possibly heterotrophic alteration products of sedimentary steroids Summons and Capon, 1991
4-Methycholestane and 4,4-dimethylcholestane diverse eukaryotic sources, high concentrations likely indicate a dinoflagellates origin Summons et al., 1994a
if strongly depleted in 13C indicative for methylotrophic bacteria (Methylococcaceae) Volkman, 2003
4-methylergostane, 4-methylstigmastane diverse eukaryotic sources, high concentrations likely indicate a dinoflagellate origin Volkman, 2003
Dinosterane in the Mesozoic and Cenozoic specific for dinoflagellates (with possible minor diatom contribution), in Paleozoic and Neoproterozoic samples probably derived from protodinoflagellates Moldowan and Talyzina, 1998, Robinson et al., 1984, Volkman et al., 1993