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et al. 1998 , 1999 ) and FAME ranging from C 6 to C 30 (Table 4.1 ). Most abundant is
the C 16 FAME followed by the C 18 and C 14 homologues. The FAME from C 12 to C 30
show an even over odd predominance. The alkane/alk-1-ene homologues are subor-
dinate in abundance relative to the FAME with an equivalent n -alkyl chain.
The FAME distribution is very similar to that in the leaves from the Miocene of
Ardèche (Gupta et al. 2007 ) where the sediment is siliceous and TOC contents are ca
1.5, over an order of magnitude lower than those of Enspel. These fatty acyl moieties
likely derive from constituent acids in cutin (Kolattukudy 1980 ), internal lipids
(e.g. phospholipid fatty acids) or a combination of both (Gupta et al. 2007 ). The
longer chain acids may be derived from free fatty acids (Gupta et al. 2007 ).
The total organic content of the sediment associated with the conifer is high
(10.6). The most abundant components of the pyrolysates (Fig. 4.6a ) are the C 2 , C 3
and C 4 alkyl benzenes followed by pristenes. C 1 and C 2 alkyl phenols were detected,
very likely derived from biogedraded lignin, along with two unknown compounds
with fragment ions m/z 131,146 (eluting after C 2 phenol) and m/z 173,188 (eluting
before napthalene). No polysaccharide, lignin and protein moieties (as observed in
the fossils) were detected in the sediment, consistent with previous results from the
same site (Stankiewicz et al. 1997a ). Py-GC-MS (Fig. 4.6a ) also reveals the pres-
ence of n -alkane/ n -alk-1-ene homologues ranging in carbon chain length from C 9 to
C 33 . The most abundant n -alkanes have chain lengths n- C 23 , n- C 21 and n- C 22 , and the
most abundant n -alk-1-enes are the C 13 , C 15 and C 14 homologues (Table 4.1 ).
Thermochemolysis of the sediment (Fig. 4.6b ) also shows an abundance of benzene
derivatives and pristenes. The fatty acid methylesters released during thermoche-
molysis range in carbon chain length from C 6 to C 28. The most abundant FAME peak
is C 22 followed by C 21 , C 16 and C 20 . The FAME in the pyrolysate from C 10 to C 28
show an even over odd predominance. The n -alkane, n -alk-1-ene homologues are
clearly discernible even in TMAH pyrolysis conditions. These range in carbon num-
ber from C 9 to C 30 . The most abundant n - alkanes are C 23 , C 21 and C 22 and the most
abundant n -alk-1-enes are C 22 , C 13 and C 21 with relative abundance comparable to
the adjoining FAME (except alkane/alk-1-ene homologue C 25 which is less abun-
dant compared to FAME n -C 22 ).
The pyrolysis trace of the fossil weevil (Fig. 4.7a ) reveals a high level of molecu-
lar preservation as indicated by the survival of chitin moieties. Preservation of pro-
teinaceous organic matter is indicated by the presence of C 1 -pyrrole (derived from
tetrapyrroles and possibly the amino acids proline/hydroxyproline) and methyl
indole, together with phenol, alkyl phenol and dialkyl phenol (all from tyrosine), and
alkyl benzenes derived from phenylalanine. Additionally, the pyrolysate is domi-
nated by n -alkane/ n alk-1-ene homologues ranging from C 9 to C 33 (Table 4.1 ) as
normally encountered in Pre-Tertiary insects (Briggs et al. 2000 ). The most abundant
n -alkanes are C 13, C 15 andC 21 and the most abundant n -alkenes are C 15, C 13 andC 22 .
Pyrolysates of weevils from other horizons in the quarry also showed the presence of
chitin and protein moieties (abundance in that order; Stankiewicz et al. 1997a ).
As with the fossil conifer, TMAH pyrolysis was conducted on the weevil to
release fatty acyl moieties. Thermochemolysis (Fig. 4.7b ) revealed the presence of
n -alkane/alkene homologues from C 9 to C 29 with both the alkanes and alkenes
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