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MUD VOLCANISM IN
AZERBAIJAN
A
quantitative study of mud
volcanoes is part of a broader project
aiming to understand the
formation of
piercement structures. The main goal is
to apply the modelling of mud
volcanoes
to palaeo hydrothermal vent systems
present in the large igneous
provinces
(e.g. South Africa,
Offshore Norway).
Azerbaijan
represents an exclusive region to study
onshore mud
volcanism. The connection between
hydrocarbons and mud volcanoes is
visible here
more than anywhere else. I conducted two
fieldworks in Azerbaijan
mapping, and sampling a
dozen of these structures. The results
reveal the origin of the fluids
feeding
mud volcanoes during their dormant
period.
See
pics gallery
below. If you
are interested in some of the
material displayed please contact
me.
Don't forget to open the pics
gallery on a separate page.
DASHGIL
Dashgil MV is one
of the structures with the strongest
seepage activity during dormant period.
Its
crater has a subcircular shape and
irregular morphology. Numerous are
the
currently active gryphons, pools, and
salsae distributed throughout the
crater.
Gryphons appear to be grouped in fields
forming in the central part of
the crater forming a ridge oriented NS
that bends towards the east.
Here
fluids with different viscosity seep
vigorously with constant flow or
with episodic
bursts with frequency that can vary from
seconds up to one minute. On
the southern side evidence of
ancient gryphon fields can be observed
with orientation W-E; at this
site burned
and melted mud breccia indicates
previous sustained burning of seeping
methane.
Inactive and eroded gryphons can be
observed on the eastern side of the
volcano. The northern side is
characterised by the presence of eroded
gryphons
and seepage features some of which are
still active (mainly pools with
gas oil-seepage). On the eastern side
two large pools show vigorous
seepage of fluids
KOTTURDAG
Kotturdag MV is
one of the three main structures present
in the Dashgil peninsula. A
longue tongue of mud breccia groves the
northern flak of the volcano
indicating the last eruption. In
the central part of the crater a
spectacular structure shows the contact
between supercompacted mud
breccia and the framing crater. On the
contact between the crater and
the squeezed mud breccia, gas is
vigorously bubbling in the small
pools.
On the eastern part of the crater a
small gryphon shows active seepage.
BAHAR
Bakar MV is
situated few kilometres
east from Dashgil MV. Unlike Dashgil MV
that shows strong seepage but
no
evidence of recent eruptions, Bakhar
MVshows also relatively fresh mud
breccia
flows on the eastern side of the
volcano. Presumably the two mud
volcanoes are
part of the same large scale plumbing
system. Isolated gryphons and
pools are
scattered inside the crater, locally
grouped in few units; some
isolated
gryphons are significantly high (several
tens of meters). Seepage
activity was
observed at all these sites as well as
microbial colonies forming mats
on the
rim of the pools. Microbial colonies
show large diversity in colour
thickness
and consistency at different pools.
Blocks of carbonate cemented
bioclast have
been observed throughout the crater.
BAHAR
SATELLITE
A
small satellite structure west of
Bahar, indicate a strong
blast eruption that left an empty crater
with steep and several metres
high wall framing the crater. The fluids
seeping from this satellite
are supposedly similar in composition to
the one seeping on the western
part of Bahar MV. This suggetss that they
have a connected plumbing
system in the subsourface. Inside
the crater are now present up
to 1m high seeping gryphons.
LOKBATAN
Lokbatan, Shongar,
Akhtarma Puta,
Gushkhana MVs are situated on the crest
of an anticline that continues
offshore
with E-W direction. The southernmost mud
volcano is Lokbatan that has
been broadly studied by academia and by
oil companies because of its
relatively
frequent eruptive activity (every 8-10
years approx) and because of the
large
oil field that is situated beneath and
around it. More then 1000 wells
are
currently active around this structure
and numerous are the
publications that
tried to describe the dynamics of this
mud volcano. No evidence of
seepage
activity was observed during our visit
(October 2005). The volcano has
elongated EW graben shape
along the direction of the main flow of
the last eruption. The crater
consists
of two main ridges interrupted by the
main mud breccia flow that forms
a tongue
directing towards W-SW. In the crater,
burned mud breccia shows the
effects of
the last methane eruption (October 2001)
that saw the gas burning for
more then
a year. Circular collapse structures are
visible framing the crater.
Fewer
structures were observed in 2002
suggesting an ongoing subsidence of
the
volcano is still ongoing. The faults
along the elongated graben
defining the
mud breccia flow support this
hypothesis. Supposedly a shallow chamber
slowly
started the process of collapse after
mud breccia eruption. Up to 15 cm
wide degassing features
have been observed throughout the most
recent mud breccia flows (last
eruption
October 2001) clearly indicating that a
large amount of gas was still
present in
the mud during the mud breccia eruption.
Circular craters up to 2 m in
diameter
were observed around the main crater
demonstrating that smaller scale
blasts
were ongoing at the time of mud breccia
release. It appears obvious
that in the
budget of gas released should be taken
in account both the first
explosive
methane blast and the following
gassified mud breccia eruption.
AKHTARMA
PUTA
Moving west
Akhtarma Puta is the second structure
positioned on the crest of the
anticline. No active
seepage
activity was observed and evidence of
strong erosion of the old mud
breccia
flows was observed. Partly eroded hollows
were observed throughout the
volcano,
presumably representing collapse
structures.
GUSHGANA
Further to the
west Gushkhana
MV doesn’t show any evidence of seepage
activity. Erosion appears
strong throughout the crater where the
altered mud breccia appears
rather poor
in clasts content. Steep up to 2-3 m high
faults and collapse walls
were
observed in the crater resembling the
features observed in Lokbatan MV.
The
volcano is recorded to be inactive since
the last 200 years.
SHANGAR
The anticline
hosting the mud
volcanoes rotates from west to north
direction and the next feature
aligned
with Lokbatan,
Akhtarma Puta,
Gushkhana MVs is Shongar MV. The
volcano reveals the presence of two
superimposed conic features presumably
representing two different
eruption
events. The top most conic feature has a
subcircular crater that is
characterised by concentric collapse
features converging towards the
central
part. Up to four metres steep walls are
characterizing the crater.
Similarly to
what observed for Lokbatan, even in this
case a gradual subsidence of
the
crater is suggested. The mud breccia
didn’t reveal significant
alteration
indicating relatively “recent” eruption.
Degassing features similar to
the one
observed in Lokbatan MV were also seen.
No evidence of active seepage
was
observed.
GARADAG
Garadag MV
presents a
circular shape with gently dipping
flanks and a wide crater with flat
morphology.
In the central part of the crater is
present a large salsa (approx 6 m
wide) where
large amount of gas is bubbling from
focused locations. The size of the
bubbles
can reach 60-70 cm in diameter. Oil
forms a biofilm in defined areas of
the salsa. Microbial colonies are also
observed in the surface and were
sampled. Inside the crater
caldera-like
features were observed. Up to 1 m high
internal walls of the crater and
large
fractures observed along the rim suggest
a gradual collapse and
subsidence of
the internal part of the crater. This
can be considered as evidence of
the deflation
of the structure following to the
eruption. No evidence of mud breccia
flows
was observed. The local flows consist of
fluidized mud.
PIREKESHKYUL
Pirekeshkyul MV shows
elongated structure with a ridge of
active gryphons
that extends along the western flank of
the crater. Pools are usually
situated
at the foot of the active gryphons. In
several instances, different
types of
fluids where observed seeping from sites
located few centimetres away,
indicating a complex plumbing system
even in the close subsurface.
KEYREKIE
Keyrekie
MV is
situated ~25 km east of
Pirekeshkyul MV. Here is visible the
emplacement of the different mud
breccia flows that clearly appear
superposed to each other. The crater has an
almost perfectly circular
shape open towards the eastern side
where the last mud breccia flow
erupted. Walls
up to 1 m high frame the crater
indicating gradual collapse and
compaction of
the mud breccia following the last
eruption. On the internal SW side of
the
crater large blocks of mud breccia
appear to have slide towards the
centre of
the crater supposedly after the cooling
and the contraction of the mud
breccia.
Various tongues of mud breccia flows are
observed especially on the
eastern
side. Mud breccia flows are thicker in
their central and thinner on the
edge
before reaching the steep and thick
walls that contain the boundaries
of the
flows. Degassing features where locally
observed and appear to be
highly
concentrated on the surfaces of isolated
“gryphon like” structures.
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Selected reading:
Mazzini,
A., Etiope,
G., and Svensen, H.,
2012, A new hydrothermal scenario for the 2006
Lusi eruption,
Indonesia. Insights from gas geochemistry: Earth
and Planetary Science
Letters, v. 317-318, no. 0, p. 305-318.DOWNLOAD
Mazzini,
A., 2009. Mud volcanism: Processes and
implications. Marine and Petroleum Geology,
26(9): 1677-1680. DOWNLOAD
Mazzini,
A., Nermoen, A., Krotkiewski, M.,
Podladchikov, Y., Planke, S. and Svensen, H.,
2009a. Strike-slip
faulting as a
trigger mechanism for overpressure release
through piercement
structures.
Implications for the Lusi mud volcano,
Indonesia. Marine and Petroleum
Geology,
26(9): 1751-1765. DOWNLOAD
Mazzini,
A., Svensen, H., Planke, S., Guliyev,
I., Akhmanov, G.G., Fallik, T. and Banks, D.,
2009b. When mud volcanoes
sleep:
Insight from seep geochemistry at the Dashgil
mud volcano, Azerbaijan.
Marine
and Petroleum Geology, 26(9): 1704-1715. DOWNLOAD
Skinner
Jr, J.A. and Mazzini, A., 2009. Martian
mud volcanism: Terrestrial analogs and
implications for formational
scenarios.
Marine and Petroleum Geology, 26(9): 1866-1878.
DOWNLOAD
Svensen, H., Hammer, Ø.,
Mazzini, A., Onderdonk,
N.,
Polteau, S., Planke, S. and Podladchikov, Y.Y.,
2009. Dynamics of
hydrothermal
seeps from the Salton Sea geothermal system
(California, USA)
constrained by
temperature monitoring and time series analysis.
Journal of Geophysical
Research (Solid Earth), 114, B09201,
doi:10.1029/2008JB006247. DOWNLOAD
Mazzini,
A.,
Ivanov, M.K., Nermoen, A., Bahr, A., Borhmann, G.,
Svensen, H. and
Planke, S., 2008. Complex plumbing systems in the
near subsurface:
geometries of authigenic carbonates from
Dolgovskoy Mound (Black Sea)
constrained by analogue experiments. Marine &
Petroleum Geology 25(6):
457-472.
DOWNLOAD
Mazzini,
A., Svensen, H.,
Akhmanov, G.G., Aloisi, G., Planke, S.,
Malthe-Sorenssen, A. and
Istadi, B.,
2007. Triggering
and
dynamic evolution of the LUSI mud
volcano, Indonesia. Earth and Planetary Science
Letters, 261(3-4):
375-388. DOWNLOAD
H. Svensen, G. Gisler,
S.
Polteau, A. Mazzini, and S. Planke, 2007,
Hydrothermal Vent complexes
and the
search of extra-terrestrial water. Lunar
and Planetary Science XXXVIII (2007) 2268.pdf
Mazzini, A.,
Ivanov, M.K.,
Parnell, J., Stadnitskaya, A., Cronin, B.,
Poludetkina, E., Mazurenko,
L., and van
Weering T.C.E., 2004.
Methane-related authigenic carbonates from the
Black Sea:
geochemical characterization
and relation
to seeping fluids. Marine Geology, 212 (1-4),
153-181. DOWNLOAD
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