25th International Meeting on Organic Geochemistry IMOG 2011

P-043
Petrological and organic geochemical characteristics of the No.
11 coal in Antaibao mine, China
Kankun Jin, Yanheng Li, Xiaoli Deng, Shenjun Qin
Hebei University of Engineering, Handan, China (corresponding author:wsaluo@163.com)
Twenty one bench samples were collected from
the No. 11 coal in the Pingshuo Coalfield. The
samples were analysed by petrological and organic
geochemical methods.
The Antaibao mine in the Pingshuo Coalfield is
located in the Shanxi province, Northern China. The
coal-bearing sequences in the Pingshuo Coalfield
include Benxi Formation and Taiyuan Formation (both
Pennsylvanian) and Shanxi Formation (Lower
Permian) [1]. The No.11 coal is in the Taiyuan
Formation and has a total thickness of 3-5m. The
thickness of the coal seam of the sampling location is
4.25 m.
Random vitrinite reflectance (Rr) was measured
by using a Leitz MPV3 reflected light microscope
fitted with a halogen lamp (oil 32/0.65, 548 nm, 3×3
�m, EMI9592 S-11; glass standard Leitz, Ro=0.889%).
The average value is 0.65% Rr. The results indicate
that the vitrinite content of the Late Carboniferous
coals from Antaibao mine varies from 17.48 to
90.91%, and the average value is 55.30%. According
to the GI-TPI diagram, the swamps of the No. 11 coal
are main lowstand systems tract and wet forest
swamps.
For organic geochemical analyses, samples were
Soxhlet-extracted for 48 h using chloroform as solvent.
Extract yields were determined gravimetrically after
removal of the solvent. The extract yields vary from
1.26 to 7.34 mg/g. The extracts were separated into
three fractions by column chromatography over prewashed
silica gel (70-230 mesh, 50×1 cm). The gas
chromatographic (GC) analyses were carried out on a
HP-5890 gas chromatograph fitted with a silica
capillary column (25m×0.2mm i.d.) coated with SE-54.
Gas chromatography-mass spectrometry (GC/MS)
analyses were performed on a Finnigan-Mat SSQ70
GC-MS. A fused silica capillary column (25m×0.25mm
i.d.) coated with SE-54 was used.
The saturated hydrocarbons occur from C11 to
C25, and the main peaks are observed before C24. The
result indicates that the predominant plant sources in
the swamps are lower aquatic organisms [2,3].
Sixty five aromatic compounds of the samples
were identified by GC/MS analysis. The data show
that they are preferentially composed of alkylated
naphthalenes and phenanthrenes. Abundant sulfur
containing polycyclic aromatic compounds were also
observed. These compounds are related to the
marine environments during swamp and peat
formation stages [4].
References
[1] Liu, D. M., Yang, Q., Tang, D. Z. (2001) Int. J.
Coal Geol. 46, 51-64.
[2] Ren, Y. J., Yang J. N., Qiu L. W., Liu K. Y.
(2010) Geol. J. China Univ. 16, 63-72.
[3] Yao, S. P., Hu, W. X., Xue, C. Y., (2004) Acta
Sedimentol. Sin. 22,519-524.
[4] Sun, Y. Z., Li, Y. H., Zhao C.L., Lin M. Y.,
Wang J. X. Qin S. J. (2010) Energ. Explor. & Exploit.
28, 97-104.
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