25th International Meeting on Organic Geochemistry IMOG 2011

P-329
Characterising the depositional environments of the massive
lacustrine source rocks of Nenjiang Formation in Songliao Basin,
China
Zhiguang Song, Qin Yin, Sibo Wang
State Key Laboratory of Organic Geochemistry, Guangzhou, China (corresponding author:zsong@gig.ac.cn)
Songliao Basin is the largest petroleum-containing
and producing basin in China. Two sets of massive
lacustrine source rocks were developed during the
Upper Cretaceous time. The major source rocks are
both in great thickness and massive distribution
associated with high abundance of organic matter and
higher hydrogen index (IH) which indicated type I and
II kerogen. The organic matter is characterized by the
high carbon numbered long-chain alkanes and longchain
alkyl naphthalenes. The organic matter were
mainly originated from the specific aquatic algae input,
while high plants input were very limited as there are
no distinguishing terrestrial biomarker identified. The
pristane/phytane ratio and the occurrence of
gammacerane and aryl isoprenoids suggest that
anoxic and salinity stratified water column were
prevailed during the sedimentation of petroleumprone
source rocks, while non-stratified water and
anoxic depositional environment were contributed to
the deposition of organic poor sediments.
Furthermore, the profile variation in the composition
and distribution of hydrocarbon including the carbon
isotopic composition suggest that there were short
period of rapid fluctuation in the climate related
environmental changes.
(This research are financially supported by the NSFC
fund of 40973033 and State ―973‖ Project
(2006CB701404)
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