25th International Meeting on Organic Geochemistry IMOG 2011

P-321
Hydrocarbon potential of Maikopian source rocks within Black
Sea petroleum basin
Dmitry Nadezhkin
Moscow State University, Moscow, Russian Federation (corresponding author:dvnadezhkin@gmail.com)
Nowadays there is huge interest in the deep-sea
part of the Black Sea region. Multiple direct features
of petroleum potential in the area such as oil and gas
seepages, active mud volcanoes, gas hydrates have
been detected.
Samples were collected during several scientific
cruises in the Black Sea within Training Trough
Research program. Rock clasts derived from mud
breccia and oil from deep sea mud volcanoes were
analyzed. Additionally collection of Maikopian
(Oligocene – Lower Miocene) oil and rock samples
from onshore drilled wells and outcrops was chosen
for comparison (fig. 1).
Fig.1. Scheme of sampling for geochemical studies.
Age determination shows that most of
semilithified rock clasts are from upper part of
Maikopian formation.
The total organic carbon content (TOC) in rock
clasts based on Rock-Eval pyrolysis varies from 0.2 to
9.37%. The hydrocarbon potential (S1+S2) is 0.25-18
mg/g that belongs to a source rock with a moderate
and good oil/gas potential. Samples demonstrated
relatively low maturity based on pyrolysis data
(maximum temperature (Tmax) less than 429 o ) and
biomarker analysis. Nevertheless samples of oil were
found in seabed sediments.
Since Maikopian sediment thickness in the
Tuapse, Sorokin and East Black Sea depressions
around 5-6 km we expect existence of active oil
generation in the middle and lower parts of formation.
As a result the question arises about the
potential of these parts of Maikopian formation.
Samples from adjacent land were analyzed to
evaluate oil/gas potential due to the lack of
information and lack of drilling in the deep part of the
Black Sea. Some of them were collected within Sochi-
Adler depression which is a continuation of the
Tuapse Trough onshore [1].
TOC in these samples varies from 0.3 to 4.06%.
Petroleum potential (S1 + S2) ranges from 0.17 to
18.38 mg HC / g rock. Thus potential of middle and
lower parts of Maikopian formation varies from low to
very high. Also values of potential increased up to
18.38 mg HC / g rock in the lower part of Maikopian
sediments within the Sochi-Adler depression and
Abkhazia region.
Finally studies show that the upper part of
Maikopian formation has enough potential to generate
hydrocarbons but it is immature.
The onshore data convincingly prove presence
of high oil/gas potential in the lower and middle part of
the Maikopian formation.
Since Maikopian sediment thickness within
depressions is around 5-6 km we expect existence of
active oil generation in the middle and lower parts of
formation.
References
[1] Afanasenkov A.P., Nikishin A.M, Obukhov A.N.
East Black Sea Basin: geological structure and hydrocarbon
potential. Moscow, 2007.
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