RESEARCH+ON+THE+INTERPLAY+BETWEEN_compressed

Interplay Between Tectonic Extensional Regime And Eustatic
Control On The Sedimentological Evolution Of The Eastern Part
Of Moesian Platform During The Late-Middle To Late Miocene,
Black Sea Near Balchik, Bulgaria
MSc. Thesis
Ruben Arismendy
Supervisor: Dr. Liviu Matenco
External supervisor: Trauian Rabagia
Free University Amsterdam, Faculty of Earth and Life Sciences
Institute of Earth Sciences, Department of Tectonics and Structural Geology

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Contents
ABSTRACT.................................................................................................................................................. 2
INTRODUCTION........................................................................................................................................ 2
1 GEOLOGICAL BACKGROUND..................................................................................................... 3
1.1 REGIONALGEOLOGY OF THE EASTERN PART OF THE MOESIAN PLATFORM................................. 3
1.2 EVOLUTION OF LITHOFACIES ....................................................................................................... 6
1.2.1 Karvuna Formation ................................................................................................................ 7
1.2.2 Odartsi Formation.................................................................................................................. 7
1.2.3 Topola Formation................................................................................................................... 7
1.2.4 Evksinograd Formation.......................................................................................................... 8
2 METHODOLOGY ............................................................................................................................. 8
3 DATA DESCRIPTION ...................................................................................................................... 9
3.1 MAJOR STRUCTURES .................................................................................................................... 9
3.1.1 Normal Faults......................................................................................................................... 9
3.2 SEDIMENTOLOGIC DESCRIPTION ................................................................................................ 11
3.2.1 Karvuna Formation:............................................................................................................. 11
3.2.2 Odartsi Formation:............................................................................................................... 12
3.2.3 Topola Formation................................................................................................................. 13
3.2.4 Evksingrad Formation:......................................................................................................... 15
4 DATA INTERPRETATION............................................................................................................ 16
4.1 STRUCTURAL INTERPRETATION ................................................................................................. 16
4.2 SEQUENCE STRATIGRAPHY ........................................................................................................ 18
4.2.1 Description of Unconformities and Sedimentary Facies...................................................... 18
5 CONCLUSIONS............................................................................................................................... 24
ACKNOWLEDGMENTS.......................................................................................................................... 25
REFERENCES........................................................................................................................................... 26
APPENDIX I: GEOLOGICAL MAP OF THE RESEARCH AREA AND OUTCROP LOCATIONS.
...................................................................................................................................................................... 28
APPENDIX II: GEOLOGICAL PROFILE............................................................................................. 29
APPENDIX III: STRATIGRAPHIC CORRELATION......................................................................... 30
APPENDIX IV: STRATIGRAPHIC COLUMNS................................................................................... 31
APPENDIX V: FIELD DATA................................................................................................................... 38

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Abstract
A conceptual geological model is created with the purpose of discuss the interaction
between extensional mechanisms and eustatic sea level changes that created particular
sedimentary depositional environments in the eastern part of Moesian platform during
the late-middle to late Miocene. The geological reconstruction of the stress fields and
evolution of lithofacies has been made from data collected along the shoreline where
fault plains and its kinematics indicators were taken and stratigraphic columns that
covered the main formation were constructed. The approach used for the structural data
was the extraction of the main stress fields (extension direction) for each family and its
relation with each sedimentary sequence. The Stratigraphic columns were analysis
using a sequence stratigraphy approach, identifying the main unconformities and
associating each sequence with its depositional environment. The study revealed a link
between extensional tectonics and eustasy that created special condition in Varna-
Balchik depression. That is, reactivation in different stages of pre Jurassic set of faults,
played and important roll in the depression evolution mainly during Besarabian, helping
to generate a Graben structure and hence increasing accommodation space in the
depocenter. Furthermore, as a result it was identified five main unconformities,
associated with four regressive cycles and three trasgressive cycles, which control the
changes in depositional environments in the area.
Introduction
The research was focused on the Easter margin of the Moesian platform at the Black
sea coastline (northeast of Bulgaria) and it covers the area along the cost between
Varna city in the southwest and Kamen Bryag town at the northeast, area that contains
the towns of Kranevo, Albana, Balchik, Kavarna, Kaliakara cape, and Balgarevo (Fig. 1).
The Neogene on the Moesian platform can be characterized with two fragments of
Paratethyan basin: Western, Forecarpathian (Central Paratethys), located over central
and west parts of the platform and Eastern, Crimea-Caucasian (Euxinian, Eastern
Paratethys) on the east part of the platform and Black sea (Fig. 2).
In the area of the external Balkanides and Moesian platform, the extension is driven by
the post-middle Miocene SE Carpatians slab pull and orogenic build-up of the
Dinarides, Bakanides and Hellenides, this extensional regime caused number of
collapses in the east of the Moesian platform. Furthermore, according with Shanov et
al., (1988) and Shanov, (1990) extensional tectonic has been acting during Pliocene,
and it is characterized by a sub-horizontal NE–SW extension.
The northern and eastern margins of Moesian platform had been study by Paramonova
et al., 2004, who found that Euxinian Sea transgressed onto large land areas during the
Volhynian–Chersonian, and proposed that the sediments in the area are control mainly
for a trasngresive process. Additionally, Kojumdgieva and Popov (1981) introduced three
main structural palaeogeographic areas.
The purpose of the present study was to discuss the interaction between tectonic
extensional mechanisms and eustatic control on the sedimentological evolution of the
eastern part of Moesian platform during Neogene. This study was based in two different
approaches, the first one is through measurements of faults and its different kinematic

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indicators and the second was the sedimentological/sequence detail stratigraphic
description of stratigraphic columns, in order to derive the effects of tectonic and
sedimentation in the Neogene evolution of the area. The structural data is represented
by normal faults, which have been activated during two different tectonic phases. In this
context, the extension direction reconstruction was made using conjugate fault sets, and
fault kinematic indicators, giving as result a general direction of NE-SW.
It was also possible to identify throughout evolution of Varna-balchik depression four
regressive cycles, three trasgressive cycles and five main unconformities. Hence, this
especial sedimentation was control by a particular topography, in which deponcenter
was driven by reactivation of normal faults. This normal faults increase subsidence in the
central part of the depression during middle Miocene, keeping the flanks in a relatively
higher position. These orographic barriers separate the depocenter from the flanks and
isolate the sedimentation during regressive periods, creating the perfect situation that
was used by sedimentation to keep low energy environment and isolated conditions,
resulting in the deposition of Topola formation.
Figure 1: Localization study area
1 Geological Background
1.1 Regional Geology of the Eastern Part of the Moesian
Platform
The Moesian Platform corresponds to a stable Precambrian block bounded to the north
and to the west by the South Carpathians, to the south by the Balkanides, and to the
east by the Black Sea (Fig.3). In order to understand the geological evolution, it is
important to refer to the end of the Neotethys Ocean, which was subducted mainly
during the Late Cretaceous-Tertiary by the collision of the dispersed pieces of
Gondwanaland with Eurasia (Sengor 1984, 1987; Sengor et al., 1988). These tectonic
movements generated the elevation of the Alpine–Himalayan mountain belt, which acted
as barrier since the beginning of the Oligocene. Consequently, in the Neogene, the
Tethys Ocean evolved into two different domains, the Mediterranean basin to the south
and the Paratethys to the north. Furthermore, during the Miocene, Carpathians tectonics
induced a further fragmentation of the Paratethys, where the Paratethys region was

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Figure3: Schematic tectonic map of the Black sea Peninsula.
Figure 2: Schematic paleographic map of the Miocene, showing the
Paratethys area (dark gray), the Mediterranean (lighter gray), and the
present day land contribution.
divided into a western and
eastern Paratethys, which
are separated from each
other by the Carpathian
mountain range (Fig. 2).
Hence, the Moesian
Platform was located in an
area covered by two
fragments of Paratethys
mentioned above. While
the Western Paratethys
was covering the central
and west parts of the
Moesian Platform, the
Easter Paratethys
(Dacian Basin and
Euxinian Basin) covered
the east part of the Moesian platform and Black sea. Furthermore Euxinian basin is
closely related to the Black sea evolution generally formed as a result of extensional
processes.
According with Dinu et al.,
2005 large-scale
extension has affected
the western sectors of
Moesia platform during
the Paleozoic, while the
entire unit has been
further subjected to
widespread simple-shear
extension and associated
basic volcanism during
the Permo-Triassic times.
During the Late Jurassic
strike-slip faulting affected
the central part of the
Moesian platform. It was
subsequently followed by local thrusting and inversion during the end of the Early
Cretaceous, in response to the coupled deformation induced by the Carpathians
tectonics (Stan et al., 2004); pre-dating the Carpathians/Balkans docking during the Late
Cretaceous Paleogene (e.g., Sandulescu, 1984; Doglioni et al., 1996).
Furthermore, the entire unit has been again affected by large scale extension during the
Early to Middle Miocene (Neogene), pre-dating the transpressional emplacement of the
thin-skinned Getic Depression foredeep on top of the northern Moesia (e.g., Rabagia
and Matenco, 1999a; Tarapoanca et al., 2003).
The Neogene sedimentation of Bulgaria is represented by marine-Brackish and
continental sediments, which were control by sea level fluctuations and Alpine tectonics.
Therefore, sea level changes were responsible for periods of massive sedimentation
followed by sediment starvation and significant erosion. Moreover, these sediments can

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Figura 5: Sketch map showing
the structural/paleogeogaphic
areas in northeast Bulgaria During
Neogene (Popov and
Kojumdgieva, 1987)
be found in Varna-Dobrogea and Burgas-Tsarevo bays, which belong to eastern
Parathetys domains (Tzankov et al., 1998) (Fig 2). Additionally these semi-isolated
basins were occasional connected to the main Tethyan realm, and their marine to
brackish or fresh water sediments contain endemic faunas (Papaianopol et al., 1995).
Figure 4: Stages subdivisions of Miocene and Pliocene according with each region.
A separate Neogene geochronology has been developed for Eastern Paratethys,
Central Paratethys and Mediterranean with different stages according with each specific
area (Fig. 4).
The evolution of the Western Black Sea basin is
characterized by Albian–Cenomanian syn-rift
extensional structures (particularly below the
Histria Depression). Late Cretaceous–Paleogene
post-rift basin fill and inversion, and Neogene
subsidence associated with extensional tectonics.
During the Neogene–Quaternary, sea level
variations, global and/or local, became the main
feature controlling the sedimentary architecture of
the western Black Sea basin (Dinu et al., 2005).
Extensional tectonic in the area during the
Neogene–Quaternary is also supported by the
results presented in the preliminary studies by
Shanov et al., (1988); Shanov, (1990). Who found
that after the Pliocene period this region was
characterized by a stress regime with sub-
horizontal 1 axis directed NW–SE, and sub-
horizontal 3 axis directed NE–SW. Moreover this
stress that has not changed until present day
according to the described process of rupturing

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Figure 6: Sketch map showing
outlines of the basin during
Sarmatian:
(Compiled after Popov and
Kojumdgieva, 1987):
that occurred during the 1986 earthquakes sequences in the area of Strajitsa and the
fault-plane solution from these two earthquakes, the general NE– SW direction of the
contemporary regional tension could be postulated (Shanov, 2005).
Furthermore, use of advanced geostatistical methods (variogram analysis and kriging)
leads to the reconstruction of the regional trend of 1 and 3 axes of the Post-
Sarmatian tectonic stress field on the studied territory. The general direction of 1 axis is
thus determined of N 121°, and of 3 axis, N 212° (Shanov, 2005).
According with Paramonova et al., 2004, the
Euxinian Sea transgressed onto large land areas
during the Volhynian–Chersonian, especially at the
northern and eastern margins; this means that the
sediments in the study area are control mainly for a
trasngresive process. Kojumdgieva and Popov
(1981) introduced three main structural
palaeogeographic areas. This areas help to
understand the general sea level changes in the
area, this areas are (Fig. 5): I. South-Dobrogea strait,
slightly uplifted area, flooded by the sea during two
short periods: first at the beginning of the Middle
Miocene, and then during the Bessarabian, forming a
sea channel to the Forecarpathian (Dacic) Basin, II.
Marginal area of the Varna–Balchik depression
comparatively stable and uplifted belt surrounding
the depression to the west and north. This area was
the shelf of the Euxinian Sea and III. Varna–Balchik
depression, which appeared at the beginning of the
Middle Miocene and was active up to the Chersonian.
During Middle to late Miocene, it has been identified
four main sea level changes in the area (Fig. 6). In the
beginning of the Volhynian, a slight probably eustatic
transgression took place (1). Later, in the beginning of
Bessarabian the sea flooded the South-Dobrogea strait (2), where shallow limestones of
the Odartsi Formation were deposited. Chemical sedimentation started in the Balchik
depression and aragonitic sediments accumulated (Koleva-Rekalova, 1994).
During the late Bessarabian to Chersonian, regression occurred (3), and before the end
of this stage, the sea abandoned northeast Bulgaria. The Chersonian is represented
mainly by laminated sediments: aragonitic laminate alternate with laminate rich in clay
minerals (Koleva-Rekalova, 1994; Ivanov and Koleva-Rekalova, 1999). The basin was
isolated from the ocean, and the salinity was lower, probably between 10–15‰ during
this period (Temniskova- Topalova, 1994).
1.2 Evolution of Lithofacies
The Moesian platform contains locally up to 2 km thick Paleogene and Neogene
continental and shallow marine sediments, 4-5 km thick relatively undeformed, generally
shallow marine Mesozoic sediments which lies on gently folded Paleozoic basement.

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This study is focused on the sequence stratigraphy and tectono-sedimentary evolution of
the upper middle Miocene to late Miocene (Sarmatian). The main formations found in the
area and their ages can be seen in Figure 4.
A general lithofacies description for the Moesian platform was extracted from the only
published references, which has been done by Robb et al,. 1998, Ivanov et al,. 2007 and
part was extracted from www.paleoworld.pillax.com Bulgarian website. Below is a
general description of the upper middle Miocene to late Miocene formation in the area.
1.2.1 Karvuna Formation
The unit is composed of dense or porous, biodetrite, fossiliferous (mainly Mactra
bivalves shells) limestones and rare oolitic and pisolitic limestones with irregular bed
surfaces, small to medium scale cross bedding and thin layers of limey clays (especially
in the areas of transition from Topola Fm). This unit overlays transitionally Topola Fm
and covers transgresivelly Odartsi Fm which has similar lithology. This is the uppermost
Miocene formation, of Chersonianian age and it is covered by transgressive boundary of
Plio-Pleistocene terrestrial deposits. Due to the different level of erosion its thickness
varies from 2-3 to 25-30m.
1.2.2 Odartsi Formation
The unit is represented by irregular interbedding of bioclastic, oolitic, fossiliferous or
sandy limestone, very hard, solid and usually porous. In some outcrops (Aladja
monastery and Cape Kaliakra) small reef buildups (Nubecularia) can be observed, with
lenses (storm channel-fill) of calkarenites and rudites or stromatolitic limestones. In the
“mechanically” deposited limestones (calkarenites and oolitic sands) medium to large
scale sigmoidal and herringbone cross bedding is developed. Laterally the unit
interfingers with the lowermost levels of the Topola and Euxinograd Fms and overlays
Frangen and Euxinograd Fms or transgresivelly Galata Fm. Its maximum thickness is
50m but it pinches out laterally rapidly. Its age is Bessarabian-Chersonian.
1.2.3 Topola Formation
The Topola formation is composed mainly by fine laminated limy clays, interbedded by
micrite limestones, of Upper Bessarabian – Chersonian age.
The unit is exposed along the seaside cliff between Albena resort and Cape Kaliakara
and is represented by thin-bedded alternation of white micrite limestones and yellowish
limey clays (in the western part) or monotonous limey clays with rare limestone layers.
The clays carbonate content is very high (50 to 60%) but reaches 80 % in some
samples. The unit overlays or interfingers laterally with Odartsi and Euxinograd Fms and
is covered transitionally by Karvuna Fm. Its thickness is around 90m around village
Topola, with a variation between 40 and 110 m.
Koleva - Rekalova 2001 described the Bessarabian aragonite sediments in this area as
massive structure, no visible bedding and interbedded by hard micrite limestone and
more rarely by clays, with beds with thickness from 0.5 to 1.0 m. The Chersonian

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aragonite sediments have a predominantly fine laminated structure, with thickness of
each aragonite-clayey layer of less than 1.0m. The color of aragonite sediments varies
from white to yellowish. They are usually unconsolidated and slightly compacted, looking
some times like a chalk (unctuous and smudge hands)
The various examinations prove that the massive aragonite sediments and aragonite
laminate are almost entirely composed of aragonite crystals (about 85-95%) (Koleva –
Rekalova 2001).
1.2.4 Evksinograd Formation.
This unit is composed of massive laminated clays and thin sandstone, limestone,
diatomaceous clays, even diatoms and fossiliferous seams, layers, beds or lenses are
common in the sequence, especially in the areas of lateral interactions or upper
boundary. The clay limy content is quite high (around 35-40%), but rare exceeds 50 %.
The unit is well exposed around the town of Varna, and along the coastline near Balchik.
The formation characterizes by complicated interactions with the synchronous units. It
interfingers with Galata, Frangen and Odartsi Fms and Limy-sandy unit, overlays Galata
and Clayey-limy unit and is covered by Odartsi and Topola Fms. Its maximum thickness
is 100-110m. Its age is Upper Karaganian-Bessarabian (Fig.7).
Figure 7: Formations present in the studied area and their age.
2 Methodology
The data acquisition was conducted mainly along the shoreline and in the accessible
areas of the cliffs; hence it was possible to take structural and stratigraphic information.
The structural deformation is mainly concentrated in the cliffs of Varna-Balchik
depression, where 17 fault plains and different kinematic indicators were taken
(slickensides and readels shears). On the other hand outside of Varna-Balchik
depression was not possible to identify important structural features and the sedimentary
sequences are not affected by important structures.
With the purpose of understanding the eustatic changes in the area, several stratigraphic
columns were taken, trying to capture all the formations present in the region, including
their lateral variations and main unconformities. In total 8 main stratigraphic columns
were constructed (Appendix IV)

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Figure 8: Typical horizontal to sub horizontal
strata in the flanks of Varna Balchik
depression.
Figure 9: Rose diagram of the
fault’s strikes found in the area
3 Data description
The structural data has been obtained along the coast between Varna city in the
southwest and Kamen Bryag town at the northeast, area that contains the towns of
Kranevo, Albana, Balchik, Kavarna and Balgarevo. Some of the data where collected
also along the road section that connects the different cities and towns in the area. A
detail description of the data and its outcrop is presented in Appendix IV.
3.1 Major Structures
The type of structures observed in the basin are normal faults, mainly in a brittle phase
with just a few outcrops in which the deformation is plastic due to unconsolidated
sediments. In some outcrops, it was possible to identify extensional joints, which can
give a clue about the smallest principal stress and the intermediate stress (Appendix IV,
Outcrop R13).
3.1.1 Normal Faults
This is the predominant fault pattern in the
area, as is mainly found in the central part
of the basin (Between Balchik and Kavarna
towns), principally associated with
Euxinograd and Topola formation and in
some cases the throw of the fault contact
these two formations (Fig 10). On the flanks
of the basin (Varna-Balchik depression), the
sediments do not show deformation, having
mainly horizontal to subhorizonal layers
without evident displacement (Figure 8).
The fault
were identified on outcrops scale, but was not
possible to identify geomorphology features related
with tectonic processes on a regional scale.
Although the strikes of normal faults found are
spread, is possible to identify some mean directions
in the rose diagram. The two main concentrations of
strike directions are from 70° to 100° and from 150° to
180° (Fig.9).

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Figure 10:Normal fault contact between
Topola and Euxinograd formation, in outcrop
R3.
Figure 11:Domino fault system in
Euxinograd formation, outcrop
R10.
According with field observation the faults in
the area can be divided into 2 groups (Fig
13): The first group is composed for six
faults with similar strike direction, which
present synthetic and antithetic relation with
each other. The mean orientation of this
group is 61°/68° and 234°/65° for the
antithetic.
Moreover, this group is characterized for
synsedimentary normal faults, which contact
Topola and Euxinograd formation.
In these faults (i.e. outcrop R3, R4, R19,
R21, R22, and R25) was possible observed offset
between 10 to 30 m and they were usually cutting the
complete sedimentary sequence (Fig.10).
The second group of faults are also represented by
normal faults, which are cutting Euxinograd formation
(i.e., Outcrops R10, R16, R17, R9 R23 and R19)
These faults are affecting part of the sequence and in
some cases only one or several layers, hence they
seem to be pre Topola deposition. The mean
orientation of this group is 350°/71° and 158°/58° for its
antithetic (Fig. 11).
Figure 12: Location of the main fault plains in the area

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Figure 14: Prograding clinoforms and its composition grains, Kaliakra
Cape.
Figure 13: Main faults associations in the area. Mean orientation for each of the fault groups A:
61/68 and 234/65, B: 350/71 and 158/58
3.2 Sedimentologic Description
The study area is composed mainly by shallow marine sediments; in which was possible
to identify energy depositional changes (laterally and vertically) and events.
Below is a description of different formations, its lithology, sedimentary structures and
main features with a first stage interpretation of depositional environment, energy
changes and depth variations.
3.2.1 Karvuna Formation:
This formation is the
younger formation in the
area (Chersonian age)
and it is located on the top
of Topola and Odartsi
formation, and it was
found in outcrops R8 and
R11, R12, R15, R31, R32
and R33. It is on the top of
the stratigraphic sequence
of the area.
As it can be seeing in the
outcrop 8 this formation is
overlain Odartsi and it is composed by biodetrite and highly fossiliferous limestones, with
a siltstone grain size matrix. The fossils are mainly bivalves shell, highly fractured and in
chaotic distribution. Moreover, it was possible to observe recrystallization and digenetic
replacements in the shells.
The main sedimentary structure associated with this formation is cross bedding which is
an indication of tidal conditions and which is consisted with the broken fossils.
This formation can be also related with outcrop R11 (Kaliakara cape), where, the last 7
meters of the stratigraphic sequence seems to be a transition zone between Karvuna
and Odartsi formation. In this outcrop and associated with clinoforms we could identify a
highly fossiliferous limestone, (i.e., bivalve shells and oolites), with fossils dissolved in

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Figure 15: Stratigraphic Column 1-Odartsi formation, detail of
high-energy deposition
Figure 15: Stratigraphic column 3, outcrop R8
some cases leaving Vugs (Secondary porosity into the rock). The fossils where broken
and in chaotic distribution, which is indicative of transport and high energy conditions.
The percentage of fossil is increasing upwards which can be indicative of Regression
(Fig. 14).
3.2.2 Odartsi Formation:
It was describe in outcrops
R6, R7, R8, R11, R29,
R30, R31, R32, and R33.
According with field
observations Odartsi
formation is characterized
by sandy limestone as
matrix with a high fossil
content (Bivalve Shells)
(E.g. Outcrop R6). In the
outcrop R6 it was possible
to identify reworked bioclastic-Pebbles and in some cases secondary porosity due to
fossil dissolution.
The biggest stratigraphic columns made over this formation are in the outcrop R8 (Fig
16), and the sequence of outcrops 30 to 34. In general terms this stratigraphic sequence
is approximately 40
meters, with 4
main
unconformities and
a sequence of
shallow water
deposits, which
can be subdivide
between high
energy deposits
(close to the
shoreline) to distal
low energy
deposits.
Mainly fined
grained limestones
(shales and mud)
compose the low
energy deposits. In
this deposits is possible to identify cycles coursing upwards, (with bivalves and oolites)
hence it is indication of different regressive cycles, which are also bounded by several
erosion surfaces (Appendix IV, Stratigraphic column 3). After the erosion surfaces it was
possible to see a important change in energy, where the sequence in made mainly by
low energy sediments (transgressive cycle).
Finally the last 15 meters show a group of high energy deposits represented by
conglomerates composed mainly by pebbles rounded and spherical, providing a clue

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
13
about a fluvial deposition environment, where we can assume is related with a
regression, and therefore with the main unconformities (Fig. 16).
The distal low energy sediments are usually silt, mud, and fined sands with centimeter
lamination. The can be found as cyclic intercalations (seasonal changes) or in some
cases it can fined or course upwards, giving an insight of the changes in depositional
energy.
This formation also was identified in the outcrop R11, R29, R30, R31 and R32, where it
is characterized by a red color Intercalation of fossiliferous Sandy Limestone with Vugs,
in which the amount of fossils usually increases upwards (reworked thin shells and
Oolites), hence is some cases it becomes matrix supported. One of the main features of
the outcrop R11 is that fossiliferous strata on the top present cross bedding and
clinoforms patters (Fig.17), this last one appearing twice in the section and which may
indicate progradation associated with a regressive system track.
Figure 16: Kaliakara cape outcrop, showing clinoforms, and high fossil percentage in the upper
layers.
Other important characteristic of Outcrop 11 (Kaliakara cape), is that in this area is
possible to observe the lateral interfigering of Odartsi formation with Topola and
Euxinograd formation (Fig. 17 ). This change is quite fast, pinching in approximately 100
from Kaliakara cape towards Balgarevo (N-W direction) and is possible to observe the
change in lithology and color of the beds.
3.2.3 Topola Formation
Topola formation is exposed along seashore, in the area between Albena and Kaliakara
cape. During fieldwork was possible to recognize a gradual change between Topola and
Euxinograd formation due to the color and size of the sediments, where Topola
formation is composed by whiter sediments than Euxinograd (See outcrop R12 in
Appendix V,). Moreover due to the normal faults present in the area it was also possible
to see an structural position of Topola in contact with Euxinograd formation, which can
be observed in outcrops R3, R4, R21 and R22.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
14
Figure 19: Euxinograd formation
fossils, in an organized distribution,
lying parallel to the lamination and
slightly broken, showing calm
deposition environment.
Figure 17: Outcrop R12, showing transition
between Euxinograd formation and Topola
Formation.
This formation is composed by cyclic sequence of white thin laminate shale (less than
one centimeter in thickness) which may indicate seasonal changes and in some cases
was possible also to identified bedding of less than 1 meter (e.g. R12, R26 and R28).
During field was not possible to make differentiation of the layers composition, but it has
been reported for this formation, alternation of white micrite-limestones and yellow limey
clays, with aragonite being the main component of the formation with about 85-95%
(Koleva-Rekalova, E., 2001).
It was also possible to identify the aragonite sediments in some of the outcrops due to its
unconsolidated and non compacted texture, being some times unctuous like a chalk.
The biggest thickness found in this formation was outcrop R12 (Fig.18), where the
sequence has about 40 meters, outcrop R14 with more than 30 meters and outcrop R26
with a thickness between 30 and 40 meters.
The sedimentary features of Topola formation and its Aragonite mineral composition,
give an insight of the deposition environment o deposition of these sediments. The
sediments of Topola formation show a clear low energy deposition environment (low
energy sediments, fined lamination), even more Aragonite needs warm and shallow
marine environments and in some cases isolation in order to get the right composition to
be deposited.
The stratigraphic column made in the outcrop
R12 shows how the sequence start with low energy sediments, associated with
Euxinograd formation, dark gray to gray sediments (due to perhaps to the organic
material content), showing seasonal cycles (Fig. 18 and 20). In these cycles is also
possible to identify a small percentage of fossils (Fig. 19), which are usually in an
organized distribution, lying parallel to the lamination and slightly broken, showing calm
to intermediate high-energy deposition environment. The main sedimentary structures in
these first meters of stratigraphic column are lamination and hummocky cross bedding
(Fig.20).

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
15
Figure 20: Seasonal cycles hummocky cross bedding
associated with Euxinograd formation.
Figure 21: Bivalves and
gastropods fossils associated
with the last meters of column 5
in outcrop R12
Upwards and with a thickness of
around 35 meters the sediments
keep fine grained changing from
shale to siltstone and mud
(seasonal cycles), but the main
change is in color and texture of
the sediments, where the
sediment get whiter and unctuous
texture, indicating an increase in
aragonite content, feature that is
characteristic of Topola formation.
The suitable depositional
environment to deposit this
sediment is either lacustrine or
shallow bay.
On the top of this sequence (the last 10 meters) is
possible to see and important change in the energy of
sedimentation, where fossils appear again (bivalves
and gastropods) (Fig. 21), showing an increase in
energy, which may be indicative of shallow water
deposits close to the shoreline. Hence, these last
meters may be representative of a transition zone
between Topola and Kavurna formation.
3.2.4 Evksingrad Formation:This formation is
exposed along the seaside cliffs between Albena and
Balgarevo, pinching out towards Kaliakara cape
(Outcrops R1 to R4, R9, R10, R13, R16 to R18, R20 to
R25 and R27). It was possible to observe tectonic
contact between this formation and Topola formation
(e.g. outcrop R3) but its relation with Topola in
stratigraphic terms is a gradual change without
unconformities(e.g. R9).
It is composed by intercalation of millimetric cyclic lamination, with fine material which is
going from silt to clay, also it was possible to identify cycles of bioclastic storm beds
(Tempestites) (Fig. 22), which consist mainly of bivalves and mollusk shells. The main
sedimentary structures in this formation are hummocky cross stratification and parallel
lamination. Hence, this sediment must be deposited in deep and calm conditions, with
some sudden energy changes associated possibly with marine storms, which deposit
high-energy material (Tempestites) over the low energy sequences.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
16
Figure 22: Detail of Tempestites layers with high fossil percentage in R19 Evksingrad Formation
4 Data Interpretation
The structural and stratigraphic interpretation was made using the data collected in the
study area. That is for the structural interpretation, it was use all the kinematic indicators
found in each fault, and it was obtain an approximation of the paleo stress field. On the
other hand, the stratigraphic interpretation was drive with the purpose of recognize the
different depositional environments and main unconformities, besides identify the
different changes in sea level. Below is the analysis and interpretation for both structural
and stratigraphic data.
4.1 Structural Interpretation
All faults found in the area are normal and located between the towns of Balchik and
Kavarna, hence the data shows that the main tectonic process that has been acting
during Neogene is extension. Moreover, the fault pattern gives insight in some cases of
lystric faults, and its associated synthetic and antithetic faults.
The fault system in the area is represented by two main directions; the first group of
faults has as main strike direction 330° to 360°, while a second group of faults has as
general strike trend between 250° and 270°, which is almost perpendicular to each
other.
This two families form two different sets, in which can be clearly separated two different
generations of faults. Thus, the first generation is represented by normal faults, but they
do not seem to cut Topola formation, which mean they were active for a short period of
time and therefore affecting older formations than Bessarabian age.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
17
Figure 24: Stress field
reconstruction according with
conjugate set found in outcrop
R16.
Figure 23: Faults contact Topola formation
and Evksingrad Formation, which throw of
more than 20 meters
The second generation of faults is
represented also by normal faults, with
offset of more than 20 meters but in this
case, they cut sediments older than
Chersonian age, mainly older than
Topola Formation (Fig 23). The
wedging shapes in the sediments in
Topola formation indicate that they are
synsedimentary. This means that while
Topola formation was being deposit, this
set of faults where active and having
and influence in the formation of Balchik
depression sediments. Thus, this faults
patters can be inherited form Pre-Jurassic structures patterns (For instance Triassic fault
patters) and having different periods of reactivation also being reactivated during
Neogene times: Therefore first period during Bessarabian and a second one during
Chersonian, and which can be still active today.
The two faults systems found in the area of study are orientated approximately at
90 from each other, which mean they have been formed by different stress states.
Despite the fact the 2 fault system were form under different stresses regime, they
reactivation of the faults is consistent with a general extension direction NE-SW
( 3=Shmin), being similar in almost all the faults, with
some variations in just 2 cases (R9 and R25) where
the extension direction found was NW-SE. Thus for
faults in outcrop R3, R4, R19 and R23 the extension
direction is NNE-SSW. Similar directions were found
for faults in outcrops R10, and R22 with ENE-WSW
extension (Fig. 24).
Furthermore the faults found in outcrop R16 are a
conjugate pair in which, it was obtain an extensional
direction of 3 is N 202° (NNE-SSW) and of 1 axis ,
N105° (Fig 24). Finally and according with this
direction of extension previously found, it was possible
to derived an extension direction ENE-WSW, in
outcrop R13 using extensional joints (with 3
perpendicular to the joints propagation).

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
18
4.2 Sequence Stratigraphy
4.2.1 Description of Unconformities and Sedimentary Facies
In the area of study is possible to find exposures of Euxinogrand, Topola, Odartsi, and
Kavurna formation, with ages form Upper Karagain to Chersonian. This stratigraphic
record is represented mainly by shallow marine sediments (less than 200m), deposited
between the continental shelf and lithoral zone areas. In this context, several
stratigraphic columns were taken, which were synthesized in 7 main stratigraphic
columns (Fig. 25 and Appendix IV).
Figure 25: Main Stratigraphic columns locations (See Appendix IV).
In the study area was possible to identify 5 main unconformities. The first and oldest
unconformity is associated with Bessarabian sediments which show a clear coursing
upwards patter, indicating a trasgressive cycle (Fig. 26). S1 is well developed mainly
towards the northeast (see appendix III) while in the central part of Varna-Balchik
depression (Depocenter of sedimentation) this unconformity is not present.
Moreover S1 unconformity marks the end of a regressive cycle follow by regression and
erosive period (localized erosion), affecting mainly the flanks of the depression, while in
de central part sedimentation of middle to high energy sediments were still on (Fig. 27).
In this respect, S1 separates shallow marine sediments from distal (low energy)
sediments. The shallow marine sediments are tempestites and indicated deposition
above the storm wave base.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
19
Figure 26: Trasgressive cycle pre S1 unconformity.
Figure 27: Regressive cycle and creation of unconformity S1.
After the erosive period that created S1, a transgresive cycle started, which is
characterized by a fast increase in sea level. Here, deposition of distal low energy
sediments are also localized in the central part of the depression, while it is getting more
costal towards the flanks, besides with channels that take the high energy sediments
farther into deeper areas. (Fig.28). Moreover the percentage of fossils in this level is
increasing towards the north and towards the east (see colums 1, 2 and 3 in Appendix
IV), and is possible to see also slumps (conglomerate lenses) and sandy material, at the
same level in the column 2, indicating some possible coarse material coming from upper
levels.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
20
Figure 28mesi: Trasgressive cycle After Unconformity S1
Figure 29: Regressive cycle and creation of subaerial unconformity S2 in the northeastern flank
of the depression.
S2 unconformity represents a second small regression with similar characteristics than
S1. It is also a limit between shallow marine-high energy to distal low energy
environment. The main difference is that this unconformity has lateritic bauxites in
almost the whole easter flank, which is indicative of subareal exposure (erosional
unconformity).
Therefore, these two unconformities spot a cyclic sea level changes during Odartsi
Formation disposition and mark the transition between Euxinogrand and Topola
formation in Varna-Balchik depression, transition that can be identify along the shoreline
near Balchik. Moreover tectonic subsidence start to be active right after deposition of

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
21
Euxinogrand formation, where reactivation of Triassic faults, enhance farther subsidence
of the depression (Fig. 29).
During the regression that creates Unconformity S2, the depocenter of the depression
was still flooded and with low energy deposition still going on, mainly in a bay
environment and with sedimentation of lacustrine type (Fig 29 and 30). This type of
conditions were thanks to the Orographic barrier such as, uplift areas in the south and
what is called Marginal area of Varna–Balchik depression according with Popov and
Kojumdgieva, 1987, which produce isolation of this area and therefore that particular
conditions (Fig . 30).
Figure 30: Onset of Transgressive cycle and isolation of de central part of Varna–Balchik
depression
Later in Bessarabian (above S2) the sedimentary record shows a distal low energy
environment along the whole area and hence a fast increase in sea level. Which indicate
a trasgresive system track (Fig 30 and 31). Distal sediments characterize the sequence
on the bottom while it is getting transitional and shallow marine towards the top (high-
energy conditions). In this context, the record shows a coarsening upwards sequence in
which is possible to identify hummocky cross stratification and conglomerates lenses
(slumps or submarine channels). Therefore, the sequence present a gradual fall in sea
level, that is recorded in the flacks of the depression and follow by a period of erosion
that is linked with the develop of lateritic bauxites (Unconformity S3). This regressive
surface may represent the end of Bessarabia age and beginning of Chersonian and
could be a sequence boundary, when Balchik- Varna depression was the only flooded
area.
Tectonics had an important roll during deposition of Topola formation (Sequence
between S1 and S3), where an important fault patters was active during some periods of
Topola deposition, as was evident in the wedge shape that some of the topola
sequences show (Fig 31 and 32).
In general unconformities S1, S2 and S3 are well develop along the Easter flank of the
area, where are quite continues while in de central part of the depression is difficult to
identified it, due to the special sedimentation conditions (Fig 33)

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
22
Figure 31: Fast transgression and deposition of low energy sediments along the area.
Figure 32: Gradual Regression and creation of subaerial unconformity S3 in the flanks of the
depression.
.
After unconformity S3, the topography of the area was relatively flat with infill of
sediments in the central part of the depression, which was under sedimentation during
regression and transgression cycles. Therefore, the orographic barriers started to be
less evident during beginning of Chersonian and onwards, stopping the isolation of the
central part of the depression, and leading to towards deposition similar lithofacies along
the area (Karvuna formation). Hence, the sea level started to increase and shallow
marine environments where predominant with high-energy evidences such as high
percentage of reworked fossil and oolitic shoals (Fig. 34). On the other hand towards the
southwest, the conditions were quite similar but the sediments show shallower

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
23
conditions, due to the fact this were farther areas reached for the transgression, being
closer to the shoreline at that moment.
Figure 33: S1, S2, and S3 unconformities along the cost, between Kaliakra cape and Bolata
beach.
Figure 34: Gradual transgression on a relatively flat topography and deposition of coastal
environment sediments.
Finally and after the transgressive cycle describe above, a regressive cycle started, with
the develop of unconformity S4, which is a wide spread unconformity in the area, and
represents a limit between high energy environments and prograding clinoforms patterns
associated with Karvuna formation. This unconformity shows lateritic bauxites in the
North West part of the area, indicating that during the regression this area was probably
in a higher topography position and having longer periods of subaerial exposure.
Moreover, sediments above S4 show an increase in grain size and percentage of fossil
upwards, hence indicating a trasgressive system track. This last regression stage can
also be evidence on the area of the abandonment of the sea during end of Chersonian
(Fig. 36).

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
24
Figure 35: Lateral interfigering of Odartsi formation with Topola and
Euxinograd formation
Figure 36: Final regression cycle with develop of prograding clinoforms on a relatively flat
topography and deposition of coastal environment sediments.
5 Conclusions
The main aim of this research is try to find evidences of the interaction of tectonic
extensional regime that has acted during the Neogene and its relation with Eustatic sea
level changes.
According with data found in the area tectonic and eustatic mechanisms were combine
to create the particular conditions of sedimentation. Such a tectonic factors where quite
important mainly in Varna-Balchik depression, where reactivation of pre Jurassic set of
faults, played and important roll in the depression evolution, helping to generate a

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
25
Graben structure and hence increasing accommodation space in this particular spot,
creating a special depositional environments suitable for the depositions of aragonite
sediments.
The structural setting in the area is clearly extensional and data found shows two
different sets of faults. These two sets are both represented by normal faults, showing
directions that can be related with older faults proposed in the area This pre Jurassic
system faults has been probably reactivated in different stages in Moesian platform and
mainly in Varna-Balchik depression. Moreover, these fault system possibly are use today
as weakness zones for new stress regime.
The structural and kinematic data show two periods of reactivation of the faults. The first
group seems to be reactivated post sedimentation of Evksingrad Formation and it is not
cutting Topola formation, which means that this faults where reactive somewhere
between the end of the Volhynian and begging of Bessarabian. Varna-Balchick
depression started to be active and which has been proposed to be at the beginning of
the Middle Miocene, Therefore this group of faults can mark the last period of
reactivation in the late middle Miocene.
Second period of reactivation occurs during deposition of Topola formation in the Varna-
Balchick depression area, which means that reactivation was acting from Middle to late
Bessarabian and possibly until Chersonian. This faults show a larger offset that the first
set, and also giving insights of syntectonic deposition, and therefore having a bigger
tectonic influence in the system.
Sedimentary record shows 5 main unconformities, which have been develop during four
regressive cycles and associated with three trasgressive cycles. Especial conditions
were developed throughout evolution of Varna-balchik depression during middle
Miocene, leading to particular topography, in which deponcenter was control by
reactivation of normal faults. This normal faults increase subsidence in the central part of
the depression, keeping the flanks in a relatively higher position. These orographic
barriers separate the depocenter from the flanks and isolate the sedimentation during
regressive periods, creating the perfect situation that was used by sedimentation to keep
low energy environment and isolated conditions, resulting in the deposition of Topola
formation.
During the infill of the basin, the depocenters were exposed to a constant sedimentation,
which made it fill faster and reach a balance with the flanks during Chersonian . That is,
the flanks where under erosive conditions during regressive cycles, which resulted in
develop of unconformities on the flanks .
Acknowledgments
I would like to thank my two supervisors Dr. Liviu Matenco from the tectonics department
of the Faculty of Earth and Life Sciences at the Vrije Universiteit Amsterdam and
external supervisor Dr. Traian Rabagia, this study could not be done without their
knowledge, support, and assistance during fieldwork and work office.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
26
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System: Correlation and Evolution of Tectonic Units. Swiss J. Geosci. 101

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
27
Shanov, S., 2005. Post-Cretaceous to recent stress fields in the SE Moesian Platform
(Bulgaria), Tectonophysics, Volume 410, Issues 1-4 , 2005, Pages 217-233, The
Carpathians-Pannonian Basin System - Natural Laboratory for Coupled
Lithospheric-Surface Processes.
Tzankov, Tz,. Popov, N. and Nikolov, G.. 2000. About the Neogene tectonic evolution
in Bulgaria. - C. R. Acad. Bulg. Sci., 53, 3.

30
S1
S2
S3
S4
S5
SC1
SC2
SC4
SC5,
SC7
SC3
SC6,

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
31
AppendixIV:StratigraphicColumns

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
32

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
33

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
34

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
35

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
36

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
37

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
38
Appendix V: Field data
In this appendix is described the most important outcrops
in the field zone that will be use to constrain the
geological evolution of the area. The locations of the
outcrops can be foundin Appendix I.
For each outcrop, we describe features such as:
-Ô±½¿¬·±² , section with thecoordinates of the outcrop.
-Ù»±´±¹·½¿´ º±®³¿¬·±² in which the outcropwas found.
-ß¹»associated with the formation.
-Ô·¬¸±´±¹§ , section where the main lithological features
will be described.
-Í¬®¿¬·¹®¿°¸§ô section with a general description of the
stratigraphic features found in the outcropò
-Î±½µ ¬»¨¬«®», section with description of the main
sedimentary structures, presents in the different beds of
the outcrop.
-Í¬®«½¬«®»-, description of the main structures found in
the outcrop including kinematics indicators such as
riedels andSlickensides.
In some of the outcrops was possible to measure all the
features while in others no all of them were reachable or
measured. For this reason, the quality of the structural
data is classifiedin:
A- First class quality data, where was possible to
measured all kinematic indicators and identified all fault
features.
B- Second class quality data, where was possible to
identified some kinematic indicators and have an
approachof the fault features.
C- Third class quality data, where was not possible to
measured any kinematic indicator, and the features of
the fault where quit confusing.
ÑËÌÝÎÑÐ Îïæ
Ô±½¿¬·±²æ X=43.21936, Y=27.97856, Z=14
Ú±®³¿¬·±²æ Lower part of Evksinograd Formation,
contact with Galata formation.
ß¹»æ Upper Karagain-Bessarabian.
Ô·¬¸±´±¹§æ Fine laminated siltstones.
Í¬®¿¬·¹®¿°¸§æ Fine laminated siltstones (mm cycles) but
also with metric bedding. It also contains bivals
associated with oxidation layer of 3 cm thick. The
material is coursing upwards. On the top is observed an
unconformity, which has beach material probably a
Terrace (Figure 1).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Crossbedding, parallel
lamination, and ripplemarks.
Í¬®«½¬«®»-æ Thebeds are dipping slightly 2˚ tothe north.
ÑËÌÝÎÑÐ Îîæ
Ô±½¿¬·±²æ X= 43.38952, Y=28.12192, Z=5
Ú±®³¿¬·±²æ Lower part of Evksinograd Formation,
contact with Galata formation.
Ô·¬¸±´±¹§å Fine laminated siltstones to shale.
Í¬®¿¬·¹®¿°¸§æ Fine laminated siltstones (mm cycles) but
also with metric bedding. The color of the sediments is
whites that in the previous Evksinograd outcrop. It shows
a centimeter layer of bioclastic storm beds (Tempestites).

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
39
Figure 1: View of the outcrop R1.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Parallel lamination.
Í¬®«½¬«®»-æ Horizontal bedding.
Ü»°±-·¬·±²¿´ Û²ª·®±²³»²¬æ Structures indicate a
possibleshallow to deep-water environment.
SW NE
ÑËÌÝÎÑÐ Îíæ
Ô±½¿¬·±²æ X=43.39852, Y=28.20438, Z=4
Ú±®³¿¬·±²æ Evksinograd Formation and Topola
formationin fault contact.
ß¹»æ Upper Karagain-Bessarabian., and Bessarabian-
Chersonian
Ô·¬¸±´±¹§æ Siltstones to shale associated to Evksinograd
Formation and whiteshales associated to Topola.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ It was not possible to measure
due to the high deformation in therocks.
Í¬®«½¬«®»-æ The main fault contacts Evksinograd and
TopolaFormation, with dragging of Topola.
Ó¿·² º¿«´¬ °´¿·²: 35˚/26˚
Ñºº-»¬: 20 m aprox.
Ü·®»½¬·±² ±º ³±ª»³»²¬ øÒ»¬-´·° ª»½¬±®÷ : 8˚/25˚
Í´·½µ»²-·¼»-: 8˚/25˚
Í¸»¿® Í»²-» : Dip slip fault-Normal
Þ»¼¼·²¹: It was not possible tomeasure.
Ï«¿´·¬§ : A
ÑËÌÝÎÑÐ Îìæ
Ô±½¿¬·±²æ X= 43.39849, Y= 28.20315, Z=4
Ú±®³¿¬·±²æ Evksinograd Formation and Topola
formationin fault contact.
Chersonian
Formation and whiteshales associated to Topola.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ It was not possible to measure
due to the high deformation in therocks.
Í¬®«½¬«®»-æ The main fault contacts Evksinograd and
TopolaFormation.
Ó¿·² º¿«´¬ °´¿·²: 0˚/72˚
Ñºº-»¬: 20 to 30m aprox.
Ü·®»½¬·±² ±º ³±ª»³»²¬ øÒ»¬-´·° ª»½¬±®÷ : 40˚/66˚-
slickensides and64˚/55˚ riedels
Í´·½µ»²-·¼»-: 40˚/66˚
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ : 56˚/15˚
Þ»¼¼·²¹º±±¬©¿´´æ 140˚/20˚
Ð®·³¿®§Î·»¼»´-æ4˚/85˚, offset: 0.02 m
Ý±²¶«¹¿¬» Î·»¼»´-æ 160˚/68˚, offset: 0.02m
Ï«¿´·¬§ : A

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
40
ÑËÌÝÎÑÐ Îëæ
Ô±½¿¬·±²æ X= 43.44123, Y= 28.54877, Z=3
Ú±®³¿¬·±²æ Galataformation.
ß¹»æ Karagain.
Ô·¬¸±´±¹§æ Sandy limestone and Conglomerates
(bioclastic Pebbles)
Í¬®¿¬·¹®¿°¸§æ Fossiliferous Conglomerate (reworked
bioclastic Pebbles), well indurated material, the matrix
seems to be sandy limestone, it shows secondary
porosity, Framework supported, micrite. The whole
sequence is fining upwards. The middle part of the
sequence shows a clear clinoforms patter (Figure 5).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Metric beddingô clinoforms
ÑËÌÝÎÑÐ Îêæ
Ô±½¿¬·±²æ X= 43.44232, Y= 28.54929, Z= 13
Ú±®³¿¬·±²æ Odartsi and Galata formation.
ß¹»æ Bessarabian andKaragain.
Ô·¬¸±´±¹§æ Oolitic limestone and Conglomerates
(bioclastic Pebbles).
Í¬®¿¬·¹®¿°¸§æ Stratigraphic sequence of approximately
20 metersô on the bottom (reworked bioclastic Pebbles),
well indurated material, the matrix seems to be sandy
limestone, it shows secondary porosity, Framework
supported. The whole sequence is fining upwards. The
top of the sequence is folded, has a whiter color and also
shows recrystallization associated with the shells. The
first ten meters shows lenses of conglomerates into
massivelimestone with metric cycles (1 m aprox.).
Í»¼·³»²¬¿®§Í¬®«½¬«®»-æ Parallel Bedding.
Figura 6: View of the outcrop R6
ÑËÌÝÎÑÐ Îéæ
Ô±½¿¬·±²æ X= 43.44258, Y= 28.54861, Z= 32
Ú±®³¿¬·±²æ Odartsi and Galata formation.
ß¹»æ Bessarabian andKaragain.
Ô·¬¸±´±¹§æ Oolitic limestone with bibals and
Conglomerates (bioclastic Pebbles).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Parallel Bedding.
Í¬®«½¬«®»-æ It seems to be Fault, which put in contact a
massive limestone, with a laminated limestone.
Figure 7: View of the outcrop R7,contact or fault zone?
ÑËÌÝÎÑÐ Îèæ Þ±´¿¬¿
Ô±½¿¬·±²æ X= 43.38101, Y= 28.47003, Z= 2
X= 43.36676, Y= 28.46609, Z= 45

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
41
Ú±®³¿¬·±²æ Odartsi and KavurnaFormation.
ß¹»æ Bessarabian and Chersonian
Ô·¬¸±´±¹§æ Fossiliferous Siltstones interbedding with mud
and shale. It also has some strata of Conglomerate and
sand.
Í¬®¿¬·¹®¿°¸§æ Stratigraphic sequence of approximately
40 metersô on the bottom Siltstone, Increasing fossils
upwards, with Porosity (fossil dissolution), with some
Interbedding of silt and mud(cm bedding).
It shows small layers of chaotic Conglomerates, with
pebbles with different composition, rounded and
spherical.
Through the middle part of the sequence, the layers are
composed by Siltstone well consolidated, Shale and very
finesand, with clinoforms (progradingsurfaces).
On the top of the sequence is possible to see layers of
laminated Siltstone, White to Grey color, with fossil’s
recrystallization (Figure 8).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Lamination, clinoforms, cross
beddig, and Horizontal bedding.
.
Í¬®«½¬«®»-æ No structures present.

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
42
Figure5:ViewoftheoutcropR5.

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
43
Figure8:ViewoftheoutcropR8anditscorrelationwiththemainunconformitiesstratigraphiccolumn.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
44
Figure 9: Fault system with W-E strike
ÑËÌÝÎÑÐ Îçæ
Ô±½¿¬·±²æ X= 43.40932, Y= 28.26114, Z=5
Ú±®³¿¬·±²æ Evksinograd and Topola Formation.
ß¹»æ Upper Karagain-Bessarabian., and Bessarabian-Chersonian
Ô·¬¸±´±¹§æ Siltstones and shales.
Í¬®¿¬·¹®¿°¸§æ Evksinograd Formation shows a Laminated
sequence of (20 cm) siltstones and shales (seasonal changes), with
a small percentage of shells and fining upwards (Figure 10). The
middle part of the cliff has white shales and horizontal bedding
associated with Topola Formation where is possible to see the
unconformities.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Cross bedding, seasonal lamination, and
metric bedding (Figure11).
Figure 10:View of the outcrop R9.
Í¬®«½¬«®»-æ The main fault is affecting mainly Evksinograd
formation, and it shows a domino faults system (extensional) on the
bottom of the outcrop.
Ó¿·² º¿«´¬ °´¿·²: 155˚/50˚
Ñºº-»¬: 0.8m aprox.
Ü·®»½¬·±² ±º ³±ª»³»²¬ øÒ»¬-´·° ª»½¬±®÷æ
Í´·½µ»²-·¼»-ïéì4 ñìë 4 ¿²¼ Î·»¼»´ ïëð4 ñëð4
Í´·½µ»²-·¼»-: 174˚/45˚
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ : 356˚/35˚
Þ»¼¼·²¹º±±¬©¿´´æ 350˚/50˚
Ð®·³¿®§Î·»¼»´-æ 150˚/70˚, offset: 0.05 m
Í»½±²¼¿®§º¿«´¬-æ 82˚/68, 75˚/70˚, 160˚/65˚
Ï«¿´·¬§ : A
Figura 11:Lamination and cross bedding related with the outcrop R9
ÑËÌÝÎÑÐ Îïðæ
Ô±½¿¬·±²æ X= 43.41228, Y= 28.27105, Z=6
Ú±®³¿¬·±²æ Evksinograd Formation.
Í¬®¿¬·¹®¿°¸§æ Laminatedsequence of siltstones.
metric bedding.
Í¬®«½¬«®»-æ The main fault is affecting mainly Evksinograd
formation, and it shows adomino faults system (extensional).
Ó¿·² º¿«´¬ °´¿·²: 0˚/85˚
Ñºº-»¬: 0.2 m aprox.
Ü·®»½¬·±² ±º ³±ª»³»²¬ øÒ»¬-´·° ª»½¬±®÷ : 88˚/28˚
Í¸»¿® Í»²-» : Strike slipfault-Dextral
Ð®·³¿®§Î·»¼»´-æ 260˚/65˚, offset: 0.02 m
Ï«¿´·¬§ : Þ

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
45
ÑËÌÝÎÑÐ Îïïæ
Ô±½¿¬·±²æ X= 43.36539, Y= 28.46537, Z= 16.
X= 43.36399, Y= 28.46530, Z= 25.
X= 43.36242, Y= 28.46573, Z= 28.
Ú±®³¿¬·±²æ Odartsi and KavurnaFormation.
Ô·¬¸±´±¹§æ Fine laminated siltstones, Sandstone and
Conglomerates
Í¬®¿¬·¹®¿°¸§æ The top of the sequence is composed by red color
Intercalation of Limestone with fossils increasing upwards (thin
shells and Oolites). It also has white to light grey Sandstone layers
with bedding and lamination.
A layer of conglomerate is associated with one of the
unconformities withpebbles size of 20 cm.
On the bottom of the sequence is possible to see Sandstone
compose by reworked limestone grains associated with the
progradingunits, some local interbedding with mudstone.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Karstification (secondary porosity)
associated with the most fossiliferous part and clinoforms, while the
cross bedding is associated mainly with sandstones. Moreover is
possible to see bedding and lamination inpart of the sequence (see
figure 14).
Í¬®«½¬«®»-æ Bedding related with clinoforms 276˚/24˚.
ÑËÌÝÎÑÐ Îïîæ
Ô±½¿¬·±²æ X= 43.38203, Y= 28.44052, Z= 4.
X= 43.38505, Y= 28.42901, Z= 45
Ú±®³¿¬·±²æ Topola and Kavurna Formation.
ß¹»æ Bessarabian – Chersonian and Chersonian
Ô·¬¸±´±¹§æ SequenceShale and Siltstones
Í¬®¿¬·¹®¿°¸§æ At this area is possible to see a transitional change
between sediments associated to Evksinograd Formation and
Topola, On the bottom the sediments are represented by Shale with
darker colors (grey and light grey) than Topola formation. Some of
the strata are fossiliferous while in other levels was not possible to
identify any fossil (Seefigure 15).
The sediment in this area dose not change upwards, keeping the
same material but changing in color, get ting whiter and becoming
what is know it the area as Topola formation.
On the top of the sequence the sequence has a change, where the
material is compost mainly by Siltstone (Matrix), with fossils
(bivalves and gastropodes), 15% to 25% fossils.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Cross bedding, ripple marks and
lamination.
ÑËÌÝÎÑÐ Îïíæ
Ô±½¿¬·±²æ X= 43.40464, Y= 28.38676, Z= 6.
X= 43.40604, Y= 28.38741, Z= 52
Ú±®³¿¬·±²æ Topola Formation (AlsoEvksinograd Formation).
Figure 13:View of the lower partof outcrop R13.
Í¬®¿¬·¹®¿°¸§æ The lower part of this sequence is made mainly by
siltstones with gray color (similar to Evksinograd Formation). The
main difference between layers is the degree of induration. Where
is possible to see pattern of extensional joints associated with the
less indurate layers.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
46
At this area on the top of the sequence the size of the material
keeps almost the same, represented mainly by shales, but
changing mainly in the color, where the material get more white
(Topola formation).
Moreover is possible to observe on the top of the sequence, an
erosion unconformity, and laying on this probably a quaternary
material (See figure 13).
Figure 16:View of the upper part ofthe outcrop R13
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Millimetric Lamination, Cross bedding,
ripples marks and metric bedding.
Í¬®«½¬«®»-æ Extensional joints: 72˚/ 75˚, 80˚/75˚, and separated
between 30 and 50 cm.
Beddinglower part: 38˚/3˚
ÑËÌÝÎÑÐ Îïìæ
Ô±½¿¬·±²æ X= 43.41244, Y= 28.3479, Z= 0.
Ú±®³¿¬·±²æ Topola Formation.
ß¹»æ Bessarabian – Chersonian.
Ô·¬¸±´±¹§æ Shale and siltstone.
Í¬®¿¬·¹®¿°¸§æ Sequence of more that 30 meters with interbedding
of Shale and siltstone, dark Grey color, getting whiter upwards
(typical feature of Topola formation), laminated, with centimeter
cycles. The layers change from none indurated to well indurated,
meter size bedding (See figure 17).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Lamination and bedding.
ÑËÌÝÎÑÐ Îïëæ
Ô±½¿¬·±²æ X= 43.43118, Y= 28.33846, Z= 121.
Ú±®³¿¬·±²æ Kavurna Formation.
ß¹»æ Chersonian.
Í¬®¿¬·¹®¿°¸§æ Stratigraphic sequence of white Shale, color, with
some small layers of fossil onthe bottom.
The top part has bigger amount of fossils and also the size of them
are bigger as well, with some recrystallization
Themainunconformities are associated withBauxite layers.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Cross bedding, Lamination, and
bedding.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
47
ÑËÌÝÎÑÐ Îïêæ
Ô±½¿¬·±²æ X= 43.41361, Y= 28.27979, Z= 0.
Ô·¬¸±´±¹§æ shales.
Í¬®¿¬·¹®¿°¸§æ Laminated sequence of shale, with some small
percentage of fossils.
metric bedding. ˚

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
48
Figure14:ViewoftheoutcropR11.

Î«¾»²ß®·-³»²¼§
×²¬»®°´¿§Þ»¬©»»²Ì»½¬±²·½Û¨¬»²-·±²¿´Î»¹·³»ß²¼Û«-¬¿¬·½Ý±²¬®±´
Ó±»-·¿²Ð´¿¬º±®³ôÞ´¿½µÍ»¿
49
Figure15:ViewoftheoutcropR12

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
50
Í¬®«½¬«®»-æ The fault system is affecting Evksinograd
formation.
Ú·®-¬Ó¿·² º¿«´¬ °´¿·² : 240˚/85˚
Ñºº-»¬: more than 2 meters.
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ : It was not
possible tomeasure.
Í¸»¿® Í»²-» : Normal
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ : 65˚/70˚
Þ»¼¼·²¹º±±¬©¿´´æ136˚/35˚
Ï«¿´·¬§ : C
Í»½±²¼ Ó¿·² º¿«´¬ °´¿·²: 340˚/65˚
Ü·®»½¬·±² ±º ³±ª»³»²¬ øÒ»¬-´·° ª»½¬±®÷ : 7˚/63˚
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ :65˚/70˚
Þ»¼¼·²¹º±±¬©¿´´æ146˚/20˚
Ð®·³¿®§Î·»¼»´-æ314˚/70˚, offset: 0.05 m
Ý±²¶«¹¿¬» Î·»¼»´-æ 306˚/90˚.
Ï«¿´·¬§ : A
ÑËÌÝÎÑÐ Îïéæ
Ô±½¿¬·±²æ X= 43.41343, Y= 28.27762, Z= 3.
Ô·¬¸±´±¹§æ shales.
Í¬®¿¬·¹®¿°¸§æ Laminated sequence of shales with small
amount of fossils.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Cross bedding, seasonal
lamination and metric bedding.
formation.
Ú·®-¬Ó¿·² º¿«´¬ °´¿·² : 10˚/65˚
Ñºº-»¬: more than 1 meter.
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ : It was not
possible tomeasure.
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ : 55˚/50˚
Þ»¼¼·²¹º±±¬©¿´´æ 30˚/20˚
Ï«¿´·¬§ : C

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
51
ÑËÌÝÎÑÐ Îïèæ
Ô±½¿¬·±²æ X= 43.4133, Y= 28.27663, Z=2
Formation and white shaleassociated to Topola.
Í¬®¿¬·¹®¿°¸§æ Intercalation of beds of siltstone and
fossiliferous shalewith recrystallization, (Lumashale).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Lamination.
Í¬®«½¬«®»-æ Bedding 0˚/20
ÑËÌÝÎÑÐ Îïçæ
Ô±½¿¬·±²æ X= 43.41337, Y= 28.27439, Z= 0.
Chersonian
Ô·¬¸±´±¹§æ Siltstones
Í¬®¿¬·¹®¿°¸§æ Sequence of fossiliferous Siltstones (mainly
snails) on the bottom. On the top is possible to see whiter
material laminated associated with Topola formation.
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Cross bedding, lamination.
formation.
Ó¿·² º¿«´¬ °´¿·²: 294˚/85˚
Ü·®»½¬·±² ±º ³±ª»³»²¬ øÒ»¬-´·° ª»½¬±®÷ : Î·»¼»´-
210˚/52˚
Í¸»¿® Í»²-» : Strike slipfault-dextral
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ : Difficult to measure due to
height grade deformation.
Þ»¼¼·²¹º±±¬©¿´´æ 40˚/270˚
Ð®·³¿®§Î·»¼»´-æ 58˚/56˚, offset: 0.01m.
Ï«¿´·¬§ : A

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
52
ÑËÌÝÎÑÐ Îîðæ
Ô±½¿¬·±²æ X= 43.41337, Y= 28.27439, Z= 0.
Chersonian
Ô·¬¸±´±¹§æ . Siltstones
Í¬®¿¬·¹®¿°¸§æ Sequence of Siltstones.
Í»¼·³»²¬¿®§Í¬®«½¬«®»-æ Cross bedding, lamination.
Í¬®«½¬«®»-æ Thefault is affecting Evksinograd formation.
Ó¿·² º¿«´¬ °´¿·²: 320˚/70˚
Ñºº-»¬: 0.21 meter.
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ : It was not
possible tomeasure.
Ï«¿´·¬§ : C
Figure 23:View of the upper partofthe outcrop R20.
ÑËÌÝÎÑÐ Îîïæ
Ô±½¿¬·±²æ X= 43.39771, Y= 28.19147, Z= 0.
Chersonian
Í¬®¿¬·¹®¿°¸§æ Sequence of fossiliferous Siltstones and
shale associatedwith Topola formation.
Í¬®«½¬«®»-æ The fault system is putting in contact
EvksinogradandTopola formation.
Ó¿·² º¿«´¬°´¿·²: 70˚/50˚
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ : It was not
possible tomeasure.
Þ»¼¼·²¹¸¿²¹·²¹©¿´´ : Horizontal
Þ»¼¼·²¹º±±¬©¿´´æ 50˚/35˚
Ï«¿´·¬§ : C

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
53
ÑËÌÝÎÑÐ Îîîæ
Ô±½¿¬·±²æ X= 43.39801, Y= 28.18996, Z= 0.
Chersonian
Ô·¬¸±´±¹§æ Siltstones and shale.
Í¬®¿¬·¹®¿°¸§æ Sequence of Siltstones on the footwall. On
the hangingwall is possible to see whiter material laminated
associatedwith Topola formation.
Í¬®«½¬«®»-æ The fault system is putting in contact
EvksinogradandTopola formation.
Ó¿·² º¿«´¬°´¿·²: 86˚/55˚
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ : Î·»¼»´-
62˚/51˚
Î·»¼»´-æ 256˚/85˚, offset: 0.02m.
Ï«¿´·¬§ : B
ÑËÌÝÎÑÐ Îîíæ
Ô±½¿¬·±²æ X= 43.39825, Y= 28.18874, Z= 0.
Í¬®«½¬«®»-æ Thefault is affecting Evksinograd formation
Ó¿·² º¿«´¬°´¿·²: 160˚/60˚
Ñºº-»¬: it was not possible to measure.
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ :
Í´·½µ»²-·¼» 194˚/55˚
Í´·½µ»²-·¼»æ 194˚/55˚
Ï«¿´·¬§ : B

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
54
ÑËÌÝÎÑÐ Îîìæ
Ô±½¿¬·±²æ X= 43.39832, Y= 28.18589, Z= 0.
Ú ±®³¿¬·±²æ Evksinograd and Topola Formation.
Chersonian.
Ó¿·² º¿«´¬°´¿·²: 242˚/55˚
Ñºº-»¬: it was not possible to measure.
Ü·®»½¬·±² ±º ³±ª»³»²¬øÒ»¬-´·° ª»½¬±®÷ : it was not
possible tomeasure
Ï«¿´·¬§ : C
ÑËÌÝÎÑÐ Îîëæ
Ô±½¿¬·±²æ X= 43.39833, Y= 28.18572, Z= 0.
Ú ±®³¿¬·±²æ Evksinograd and Topola Formation.
Chersonian
Ó¿·² º¿«´¬°´¿·²: 218˚/55˚
Ñºº-»¬: more than 20 m
Í´·½µ»²-·¼»æ 170˚/45˚
Ï«¿´·¬§ : B

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
55
ÑËÌÝÎÑÐ Îîêæ
Ô±½¿¬·±²æ X= 43.39495, Y= 28.12497, Z= 98.
Ú ±®³¿¬·±²æ Topola Formation.
ß¹»æ Bessarabian-Chersonian
Í¬®¿¬·¹®¿°¸§æ Sequence of Siltstones and shale of around
30 to 40 meters. On the top is possible observed some
oxidizedlayers similar to the one on Odartsi formation.
Í¬®«½¬«®»-æ The whole sequence seems to be horizontal,
but is tiding towards theshore.
ÑËÌÝÎÑÐ Îîéæ
Ô±½¿¬·±²æ X= 43.39785, Y= 28.13400, Z= 4.
Í¬®¿¬·¹®¿°¸§æ Sequence of Siltstones of more than 10
meters.
Í¬®«½¬«®»-æ Thewhole sequence seems tobe horizontal.
ÑËÌÝÎÑÐ Îîèæ
Ô±½¿¬·±²æ X= 43.40914, Y= 28.158113, Z= 68.
Ú±®³¿¬·±²æ Topola Formation.
ß¹»æ Bessarabian – Chersonian.
Í¬®¿¬·¹®¿°¸§æ Sequence of more that 20 meters with
interbedding of Shale and siltstone, dark Grey color, getting
whiter upwards (typical feature of Topola formation),
laminated, with centimeter cycles. The layers change from
none indurated to well indurated, meter size bedding, is
possible to see a continues sedimentation without visible
uncoformities (See figure31).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Metric Bedding, lamination.
ÑËÌÝÎÑÐ Îîçæ
Ô±½¿¬·±²æ X= 43.42937, Y= 28.53502, Z= 0.
Ú±®³¿¬·±²æ Odartsi Formation.

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
56
ß¹»æ Bessarabian.
Ô·¬¸±´±¹§æ Siltstone and conglomerate.
Í¬®¿¬·¹®¿°¸§æ On the bottom of the sequence is composed
by Siltstone with oolites, 70% of fossils with secondary
porosity due to fossil dissolution. Upwards is possible to
observe lenses of conglomerate (matrix supported), with
some layers with bauxite (See figure 32).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æMetric bedding.
Í¬®«½¬«®»-æ Bedding N55/15W
Figure 32 View of the outcrop R29
ÑËÌÝÎÑÐ Îíðæ
Ô±½¿¬·±²æ X= 43.43942, Y= 28.54615, Z= 24
Ú±®³¿¬·±²æ Odartsi Formation.
ß¹»æ Bessarabian.
Ô·¬¸±´±¹§æ Sandstones.
Í¬®¿¬·¹®¿°¸§æ Sequence of Sandstones, with oolites, fossils
and some pebbles, coarsening upwards. The matrix is
mainly fossil fragments (shells), and dissolution process
created vugs. (See top part of figure 33).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æMetric bedding.
Figure 33 View of the outcrop R30 on the top and 31 on the bottom.
ÑËÌÝÎÑÐ Îíïæ
Ô±½¿¬·±²æ X= 43.44286, Y= 28.5495, Z= 1
Ú±®³¿¬·±²æ Kavurna-Odartsi Formation.
ß¹»æ Chersonian-Besarabian.
Í¬®¿¬·¹®¿°¸§æ This sequence is made by interbedding of
white Siltstone and shales, with some % of fossils
associated with some of the levels. It also shows green
salty layer and other orange layers due to oxidation
processes. Towards the bottom the percentage of fossils
increase, where is possible to observe large reworked
pebbles and fossils (5 cm) with vugs associated. (See Top
part of figure 34).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æ Metric bedding, lamination.
ÑËÌÝÎÑÐ Îíîæ
Ô±½¿¬·±²æ X= 43.44117, Y= 27.9466, Z= 247
Í¬®¿¬·¹®¿°¸§æ Repetitive sequence of white Shale and
Siltstone with large pebbles and fossils. (See middle part of
figure 35).

Î«¾»² ß®·-³»²¼§
×²¬»®°´¿§ Þ»¬©»»² Ì»½¬±²·½ Û¨¬»²-·±²¿´ Î»¹·³» ß²¼ Û«-¬¿¬·½ Ý±²¬®±´
Ó±»-·¿² Ð´¿¬º±®³ô Þ´¿½µ Í»¿
57
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æMetric bedding and lamination.
ÑËÌÝÎÑÐ Îííæ
Ô±½¿¬·±²æ X= 43.44032, Y= 27.94747, Z= 240
Ô·¬¸±´±¹§æ Siltstones and Sandstone.
Í¬®¿¬·¹®¿°¸§æ This part of the sequence is fining upwards
and I s mainly characterized by an interbedding of
fossiliferous Siltstone and Sandstone (See bottom part of
figure 35).
Í»¼·³»²¬¿®§ Í¬®«½¬«®»-æMetric bedding and crossbeding

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