Geology Reference
In-Depth Information
A
Isoprenoid
hydrocarbons
Subbituminous
coal A
Hams Fork Region WY
PSOC 1487
Normal
alkanes
Pr
Ph
Plant waxes
B
High-volatile
bituminous coal C
Uinta Region UT
PSOC 1503
C
High-volatile
bituminous B
Uinta Region CO
PSOC 1501
D
High-volatile
bituminous A coal
Breathitt Formation
Hazard Bed No. 7
Perry County, KY
KY 4530
Retention time
Figure 11.3.3. Saturated hydrocarbon fingerprints (
85) of selected coals by increasing rank. These fingerprints
employ GC/MS to reduce the effects of aromatic and heteroatomic compounds that obscure these signatures in the
GC/FID fingerprints. The purified saturated hydrocarbon signature demonstrates some unique features of coal
commonly encountered in environmental samples: (A) subbituminous coal exhibits the early stages of normal
alkane and isoprenoid formation, (B) high-volatile bituminous C coal continues this process while demonstrating a
pronounced enrichment of pristine relative to phytane (
m
/
z
), (C) high-volatile bituminous B coal also from the
Uinta Formation retains the high ratio of pristine to phytane while demonstrating a slight reduction in the plant wax
signature, and (D) high-volatile bituminous A coal from the Breathitt Formation share the high proportion of
pristine relative to phytane and the continued geochemical reduction of the plant wax signature.
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