| biomarker |
biological and/or environmental interpretation |
references |
| n-alkanes |
| outstanding concentrations of n15, n17 and n19 in early Paleozoic rocks |
Gloeocapsomorpha prisca, marine phytoplankton of uncertain affinity, probably an alga, identified in Cambrian-Devonian sediments but most prominent in Ordovician. Estonian kukersite is a typical source |
Blokker et al., 2001, Fowler, 1992 |
| n-C27 with OEP1 |
waxes derived from higher plants, terrestrial input, post-Silurian age |
Hedberg, 1968, Tissot and Welte, 1984 |
| n-C40 |
predominantly degradation products of aliphatic macromolecules such as algaenan (marine, lacustrine), cutan and suberan (terrestrial, plant derived) |
Allard et al., 2002, Killops et al., 2000 |
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| branched alkanes and acyclic isoprenoids |
| monomethylalkanes and dimethylalkanes (MMA and DMA) |
cyanobacteria both cultured and in mat communities from hypersaline and hydrothermal environments |
Dembitsky et al., 2001, Kenig et al., 1995b, Koster et al., 1999, Shiea et al., 1990 |
| 5, 5-diethylalkanes with OEP1 (wrongly reported as 3, 7- or 3,w7-dimethyllkanes) |
these structures widely and incorrectly assigned. Chemical synthesis of a 5, 5-diethylalkane indicates this is a major series. Often occurs with other alkanes with quaternary carbon centers (BAQCs). Source organisms not known but commonly found in association with benthic microbial mats. |
Arouri et al., 2000a, Arouri et al., 2000b, Kenig et al., 2002, Logan et al., 1999, Logan et al., 2001, Simons et al., 2002 |
| pristane (Pr) and phytane (Ph) |
from chlorophylls of cyanobacteria, algae and plants, bacteriochlorophylls a and b of phototrophic bacteria, tocopherols, Ph: archaeal membrane lipids |
Peters and Moldowan, 1993 |
| regular acyclic isoprenoids i-21 to i-30 |
probable source is halophilic Archaea, abundant in evaporitic environments |
Grice et al., 1998b |
| squalane (tail-tail C30 acyclic isoprenoid) |
all organisms produce some squalene, most sedimentary squalane probably from Archaea. |
Grice et al., 1998b |
| crocetane |
archaea (anaerobic methane oxidizers), associated with sub-sea gas, gas hydrate and mud volcanoes |
Bian et al., 2001, Thiel et al., 1999 |
| PMI (2,6,10,15,19-pentamethylicosane) |
methanogenic and methanotrophic archaea |
Elvert et al., 1999, Schouten et al., 1997, Thiel et al., 1999 |
| TMI (2,6,15,19-tetramethylicosane) |
only reported from a mid-Cretaceous oceanic anoxic event, nonhyperthermophilic marine Crenarchaeota? |
Kuypers et al., 2001 |
| C20, C25, C30 and C35 highly branched isoprenoids |
unsaturated and polyunsaturated isoprenoid hydrocarbons are prominent biochemicals in some diatom taxa such as Rhizoselenia and Haslea |
Sinninghe Damste et al., 1999a, Volkman et al., 1994, Belt et al., 2000, Rowland et al., 2001 |
| botryococcenes and botryococcanes, cyclobotryococcenes, polymethylsqualenes |
the unsaturated, sometimes cyclic, biogenic hydrocarbons and their saturated fossil counterparts are diagnostic markers of the chlorophyte B. braunii and their preferred habitat of fresh to brackish water. |
Huang et al., 1988, Metzger and Largeau, 1999, Summons et al., 2002 |
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| monocyclic saturated hydrocarbons |
| C42 - C46 cyclopentylalkanes with OEP1 |
oils from marine environments, unknown biological source |
Carlson et al., 1993, Hsieh and Philp, 2001 |
| C42 - C46 cyclopentylalkanes with no distinct carbon preference |
oils from freshwater lacustrine settings, unknown biological source |
same as above |
| C42 - C46 cyclopentylalkanes with strong EOP2 |
oils from saline lacustrine settings, unknown biological source |
same as above |
| cyclohexyl alkanes without predominance |
formed during pyrolysis of biopolymers with long aliphatic carbon chains suggesting an origin from acyclic polymethylenic precursors |
Gelin et al., 1994 |
| macrocyclic alkanes C15-C34 without preference |
bitumens extracted from torbanites containing remains of B. braunii, fresh to brackish water |
Audino et al., 2002 |
