Steroids triaromatic

Figure 4 Distribution of triaromatic steroids (68) in GC-MS m/z = 231 selected ion chromatograms in (a) a Phanerozoic oil of low thermal maturity, (b) a mature Phanerozoic oil, and (c) an overmature bitumen from the late Archaean Fortescue Group in Western Australia. The inset in (c) is a 20 X magnification of the elution range of C26 to C28 triaromatic steroids (68b) (Brocks et ah, 2003a,b) (reproduced by permission of Elsevier...

Dahl J. E. P., Moldowan J. M., Summons R. E., McCaffrey A. M., Lipton P., Watt D. S., and Hope J. M. (1995) Extended 3-alkyl steranes and 3-alkyl triaromatic steroids in crude oils and rock extracts. Geochim. Cosmochim. Acta 59, 3717-3729. [Pg.3972]

Figure 6 Diagenetic conversion of sterol (I) to various aromatic hydrocarbons during diagenesis. Abbreviation M implies that the reaction involved multiple steps, R represents aromatization of the A ring, and L represents the aromatization of the B ring. Compounds II, V, and VI are intermediates for the formation of triaromatic steroids...

R. Maxwell, J. R. 1989. Laboratory thermal alteration of triaromatic steroid hydrocarbons. Organic Geochemistry, 14, 109-111. [Pg.205]

Fig. 29. Haltenbanken fluids are phase separated reflecting the vertical migration, and molecular patterns of triaromatic steroids, for example, are influenced by phase fractionation, hence the C20 triaromatic steroid will be enriched relatively to the C28 compound in the gas phase, whilst the C28 compounds will be partitioned with relative enrichment into the oil phase (oil leg). These effects often pnzzle interpreters, but are readily rationalized in relation to vapour pressure of the compounds (cf. Karlsen et al. 1995). Figure modified after England Mackenzie (1989).

$Fig. 29. Haltenbanken fluids are phase separated reflecting the vertical migration, and molecular patterns of triaromatic steroids, for example, are influenced by phase fractionation, hence the C20 triaromatic steroid will be enriched relatively to the C28 compound in the gas phase, whilst the C28 compounds will be partitioned with relative enrichment into the oil phase (oil leg). These effects often pnzzle interpreters, but are readily rationalized in relation to vapour pressure of the compounds (cf. Karlsen et al. 1995). Figure modified after England Mackenzie (1989).$

Phase fractionated condensates and oils from Haltenbanken have an effect on the gross composition, GOR and API of the petroleums (Karlsen et al. 1995). The ratio of hopanes to steranes, triaromatic steroid maturity parameters, and, in extreme cases, also the Pr/Ph, Pr/ -C)7 and Ph/ -C 8 ratios and the carbon isotope values are altered by this effect (Karlsen et al. 1995). The effect on the latter is due to... [Pg.345]

Fig. 5. Changes in C4-benzene isomer ratios in Fort Worth Basin oils and condensates as a function of triaromatic steroid maturity parameter.

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...