Abnormal deflection in the some folded axes within Zagros fold and Thrust Belt, Northern Iraq, Mirawa-Mawaran synclinal axis as a case
Study
Abdalla Amir Omar
Department of Geology
College of Science-University of Salahaddin
Iraq-Arbil- North Iraq
e-mail: [email protected]
Abstract: The Mirawa-Mawaran synclinal structure was studied in order to establish the cause of
the deflection in the fold axis from one segment to another. Field data obtained from two structural
sections perpendicular to the major fold axis, one of the section located in the Mirawa segment, while
the second section located in Mawaran part. This study indicates that the attitude of the fold axis within
Mawaran segment is 300/03, with axial plane attitude 121/77, that indicate northeast vergence fold. In
the Mirawa segment, the axis of the fold is 146/11, with axial plane attitude of 328/82 that refers to
southwest vergency.
The deflection of the fold axis is attributed to presence of major lineament in the middle junction of
these two segments that coincide with a set of strike-slip, normal and reverse faults in this zone. The
model of evolution for that syncline is discussed, and assumed to be related to bending of whole
syncline at that junction part which coincide with that faults. This junction part may coincide with
boundary of basement block that manifested on the surface as lineament or as different types of the
faults.
Key word: Syncline, Mirawa, Mawaran , vergency, fold axis, deflection, lineament
Introduction:
The geographic theater of the studied area is
situated about 45 Kilometers to the northeast of
Arbil city in Iraqi Kurdistan Region. This area
occupied by a narrow, elongated, oval shape, double
plunging synclinal fold that trending northwest-
southeast parallel to the Zagros fold belt. The whole
area, which this study deals with it, is bounded by
latitude (36˚ 15` - 36˚ 30`) and longitude (44˚ 15` –
44˚ 30` ) (fig.1). Locally this synclinal
structure named Mirawa syncline, but in this study
we call it Mirawa- Mawaran syncline because it
composed of two structurally different segments, one
located at southeastern part named Mirawa, while
the northwestern part called Mawaran segment with
respect to Mawaran village.
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Tectonically, this syncline located within High
Folded Zone of the Unstable Shelf of Iraq (1)
(Fig.2A), while according to Numan (2) is located
within Forland basin of the Zagros thrust belt
(Fig.2B). The folded zone of Iraqi territory is
divided to elevate and unelevated structural subzone
(3) where the present studied area located within
elevated one (Fig.2C). According to Al-Azzawi (4)
this syncline situated in Parabolic-Semi Ellipse fold
to Sinusoidal –Parabolic fold sectors (Fig.2D).
Geomorphological setting of the studied
area closely connected and controlled by tectonic
fabric of the northern Iraq. The general
geomorphology of area can be divided onto three
main groups of Landforms: anticline ridges,
structural denudation hills and slopes, and fluvial
accumulation plains. The anticline ridges comprise
the oldest rock units cropping out in the cores of the
major anticlines which surrounding this syncline,
with a characteristic dip slope and flat Iron
topography around the cores, which defines the
shape of this synclinal fold.
The fluvial accumulation plains are mostly
developed in synclinal valleys. They cover very
wide parts of terrains; the landform is covered by
gravel, sand and mud of quaternary age. Genesis of
these sediments is connected with river flood plain,
river terraces, alluvial fans, cone deposits and recent
deposits and soil. However, the drainage network
comprehends perennial and temporary water course,
and even permanently dry valleys, but it caused the
fluvial process in the studied area is limited to the
several bigger rivers, all of them left tributaries of
the Greater Zab River, most of the rivers and stream
coming from high mountains, as this is
neotectonically active zone, even at the present days,
mountains are uplifting and rivers in effort to cancel
it are reinforcing their incising, forming deep
canyons. This occurrence is well known under the
name “antecedence”.
Fig.(1): Location map of the studied area
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(A) (B)
( C ) (D) Fig.(2): Tectonic position of the studied area with respect to: (A): Buday and Jassim,1987 (B): Numan,2000 (C): Maruoof,1999 (D): Al-Azawi,2003
State of the problem: Although the Mirawa-Mawaran syncline is
generally takes the same trends like Zagros Fold Belt
(i.e. NW-SE), but locally the deflection that happen
in the fold axis of this syncline is considered to be
the main structural problem which is worthwhile.
Accordingly the main purpose in this article is
related to study of structural characteristic for each
part of this syncline, in order to detect the cause of
that deflection which happens in the fold axis from
one part to another. The above purpose need
collecting data from field and previous study and
treating these data statistically in structural point of
view which is another purpose in this work.
Methodology: The work which done during the preparation of
this research can be divide in to two stages, one
concerning the field work and second is the office
work. Details of each one describe in the following
paragraphs.
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(A): Field work: In the present study, field measurements and
observations were carried out in 20 field stations
distributed along two structural traverses taken
perpendicularly to the Mirawa-Mawaran fold axis
trend. Two day of field work was sufficient for
collecting the required data, as well as auxiliary data
were taken from Οmar (5) such as more bedding
plane attitude and data about faults and geological
formations.
One of the traverse located in northwestern segment
of the syncline i.e. within Mawaran portion of the
syncline, while the second traverse located within
the Mirawa segment in most end of the syncline at
southeastern side. The total number of (118) reading
about bedding planes was measured using Brunton
compass. In the field the correction was done for the
magnetic declination. Each field station covered an
area of about 30-50 m2. The following important
structural elements recorded at each field station:
1- Measuring the attitude of bedding
planes.
2- Measuring attitude and type of
faults.
3- Recording layer thickness, lithology
and some mesoscopic fractures such as joints,
veins…..etc.
4- Plotting the position of the each
field station in the field on topographic base map.
(B): Office work: Schmidt equal-area net was used to analyses the
field data. The poles of bedding planes were plotted
on the pi-diagram in order to determine some
geometrical properties of that fold in different
position i.e, Mirawa and Mawaran segments of
syncline.
In order to show these data in a proper way in
the report the all data were redrawing again using
SteroWin software, which is one of the professional
software used nowadays in plotting these types of
the structural data. The pi-diagrams were used to
demonstrate the following:
1- Measuring the mean attitude of each
limb within each traverse for Mawaran and Mirawa
segments of the studied syncline.
2- Calculating and determining the fold
axes within each segment to show the variation in
direction and plunging of this syncline within the
two segments.
3- Determining the attitude of axial
plane for each segment of the fold.
4- Calculating interlimb angle for the
fold.
5- The Landsat images were also used
and interpreted for whole studied area in order to
delineate the major lineaments, which affect this
syncline; the lineaments were checked latter in the
field.
Stratigraphy of studied region:
Geological map (Fig.3), as well as columnar
section (Fig.4) for this synclinal structure are drawn
partly from the field and from the explanation notes
taken from Summer field trip manual by Omar(6), as
well as from Οmar (5),which are as follow:
Kolosh Formation:
This formation is exposed in all the
structures of the high folded zone, within the
mapped region. Generally it forms gently elevated
areas, which are dissected by dense drainage system,
due to the predominance of the soft rocks in the
formation. The formation consists of clastic rocks
that are dark gray and black in color. The rocks are
shales, claystones, sandstones, siltstone with
conglomerate. The age of this formation is
Paleocene – Lower Eocene (7).
The sandstone beds are generally dark gray or
black in color, friable, medium to coarse grain. The
thickness of the sandstone beds ranges from 0.15m
upto 0.8m. Occasionally they are pebbly, the pebbles
are small in size, not more than 2-3cm. The shales
and claystones of this formation are soft papery and
fragmented, and are weathered. The thickness of the
formation is variable and increases southeastwards.
In Shaqlawa its thickness ranges between 140 and
180m. Dolomitic limestone beds representing the
Khurmala Formation are interbedded within the
Kolosh Formation.
In Safin Anticline (SW limb of Mirawa syncline)
the appearance of thin bedded sandstone is
considered to be the contact between this formation
and underlying Shiranish Formation (8). The upper
contact of the Kolosh Formation is gradational with
the Khurmala Formation. The total thickness of the
Kolosh Formation is variable; it increases towards
southeast of the investigated region
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Khurmala Formation: This formation, found as a series of ridges
around most of the anticlinal structures in the studied
region, belongs to the Early Paleocene – Early
Eocene time span (7). It consists of limestone which
is dolomitic, crystalline, fossiliferous. Fossils found
within this formation are some large gastropods
whose lengths reach up to 20cm. The color of the
limestone beds is yellow, in some localities creamy,
well bedded, the thickness of individual beds ranges
from 0.5-3.0m. The beds are relatively hard, because
they are overlain and underlain by soft materials
(clastics). They always form ridges and scarps over
the whole area. At the vicinity of Shaqlawa town,
one or two horizons of limestone occur. Gercus Formation:
This formation is of Middle Eocene age (9),
is exposed in all the mapped structures of the studied
region. It generally forms steep slopes below the
hard limestone of Pila Spi Formation, which forms
high and steep ridges (mostly anti-dip). Soft rocks
are the main constituents of this formation; hence it
is dissected by a dense drainage pattern, which forms
parallel rills and galleys. When the slopes are gentler
the rocks are mainly weathered and covered by red
soil. The formation consists of red clastic rocks,
which are mainly claystones, siltstones, and
sandstones with thin horizons or lenses of
conglomerate that vary vertically and laterally.
The main rock type of this formation is the
claystones, which are reddish-brown, brown and
rarely violet, soft to fairly hard and fragmented to
small chipses 3-4 cm in size. Sandstones in this
formation are less abundant than claystones and
occur as thin beds 0.5-3.5m, they are also reddish
brown and brown in color, hard, bedded, the
thickness of individual bed is 0.1 to 0.8m, fine to
medium grained.
Limestone horizons may occur within this
formation. They become thicker in the middle and
southeastern parts of the studied region. These
limestones exist as Tongues within this formation,
white, light gray in color fairly hard, well bedded,
highly fractured, its thickness ranging from 0.3to2m.
These limestone beds represent short-lived marine
incursions and are supposed to be equivalent of the
Avanah Formation of Middle Eocene (10).
The lower contact of this formation with the
underlying Kolosh or Khurmala Formation is
conformable; the contact in the field is sharp and
clear due to color difference, while the upper contact
is unconformable in all of the mapped areas with the
Pila Spi Formation. Thickness of this formation
varies from one place to another.
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Fig.(4): Generalized geological columnar section for studied area
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Pila Spi Formation: This formation belonging to Middle-Late
Eocene age (7) is exposed in the entire studied
region. It is seen as continuous high ridges
surrounding the synclinal structures with very
common flat iron morphology, while in the other
places it forms the carapace of main body of the
anticline as in case of the Pirmam Anticline.
The formation consists mainly of limestones,
which are crystalline, dolomitic, clayey or chalky
and sometime dolomitic. The color is white, creamy,
light gray, well bedded. The upper beds of this
formation contain Iron oxides and chert concretions
up to few centimeters in size, and rich in limonite
concretions.
The lowermost part of this formation
consists, of conglomerate, which marks the
unconformable contact with the underlying Gercus
Formation. This conglomerate consists of chert
pebbles, chalcedony, flint, jasper, some igneous
rocks and limestone also occur. In some areas, thin
lenticular limestone horizons may occur within
conglomerate. In northeast limb of the Safin
Anticline, green colored cement materials were
found in the conglomerate thought to be of copper
(10). The maximum thickness of the conglomerate
beds reaches up to 6m, such as near Shaqlawa City.
The thickness of the formation is highly variable.
The formation is deposited in a lagoonal
environment (7).
Fathُa Formation (Lower Fars Formation): This formation covers most of the studied
region as a continuous belt around most of the
anticlinal structures and the troughs of the synclines.
This formation is of Middle Miocene age (7).
Geomorphologically the formation forms hilly area
with continuous ridges of thick limestone forming
cuesta and hogback features around most of the
anticlines.
The formation in the studied areas consists
of cyclic deposits of claystone, limestone and marls
with the presence of lenses of gypsum as in the
southwestern limb of Mirawa-Mawaran syncline.
The main color is reddish brown with some green
and blue colors which occur in the lower parts. The
claystone is soft, fragmented into small chips,
occasionally it is silty, conchoidal fracturing is
common in the claystone. The limestone is also one
of the main constituents of the formation. It is light
gray, white, light brown, hard, well bedded, some of
beds are fossiliferous, fossils are mostly shells of
Pelecypods and gastropods up to 5cm in size. Others
are recrystallized, sandy limestones are common,
more towards the lower parts of this formation, some
of the limestone beds are underlain by green marl or
marly limestone.
The lower contact of this formation with the
underlying Pila Spi Formation is unconformable
marked by presence of basal conglomerate. Due to
the lithological difference between Pila Spi and
Fatha Formations; the contact is easily followed in
the field. It is also very clear geomorphologically
due to difference in the degree of resistance to
erosion between the two formations.
Injana Formation (Upper Fars Formation): The age of the formation is Late Miocene
according to Bellen et al (7). This formation is
exposed in the core of synclines within the studied
region. Geomorphologically, the formation forms
hilly areas with continuous strike ridges and valleys
due to alternation of hard and soft rocks.
The formation consists of cyclic deposits of
clastics, which in general coarsen upwards. The
dominant color of the clastics is red color. Each
depositional cycle consists of mudstone and
sandstone. The mudstone is occasionally silty with
some thin horizons of interbedded siltstone, which
are reddish brown, and brown in color and are 0.1-
0.5m thick. The claystone is reddish brown, grayish
brown, and rarely green and violet in color, soft to
fairly hard, weathered in some places usually
covered by soil, which is silty and sandy. The
sandstone is the second main constituent of the
formation; the main color is reddish brown to brown,
bedded, and the thickness of the individual beds
ranges from 0.1m up to 4m. Fracturing and Jointing
are well developed in the sandstone. The sandstones
are rich in sedimentary structures among them, mud
balls; cross bedding, ripple marks; and burrowings
are common.
The lower contact of the formation with the
underlying Fatha formation is conformable it is
recognized in the field by the uppermost limestone
horizon of the Fatha Formation which is always
overlain by a thick red claystone bed.
Mukdadiya Formation (Lower Bakhtiari Formation):
The formation is exposed in some synclines
of the studied region such as in the northeastern limb
of the Mirawa (Mawaran) syncline. The formation
consists of cyclic deposits of clastic material fining
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upwards. The cycle starts by claystone, pebbly
sandstone and thick layers of the conglomerate, in
some other places it start by pebbly sandstone, thin
beds of the claystone and thick beds of the
conglomerate. Siltstone occurs either as thin beds or
as silty materials within the claystone. The
conglomerates covers the claystones and the size of
the pebbles reaches to 25cm. The thickness of the
conglomerate beds is 20-35m. The shapes of the
pebbles within the conglomeritic beds are spherical,
bladed and rounded.
The lower contact of this formation with the
underlying formation is diachronous (9). This
contact is recognized lithologically by the first
occurrence of the pebbly sands. Pebbles usually
occur on lamination surfaces or along surfaces of the
cross bedding, they are of small size. The pebbles
may disappear laterally and reappear again along the
same bed, so the contact might be missed easily in
the field if no careful attention is paid to the
occurrence of the pebbles. The mode of the
deposition is continental, and it is the Molasse
sediments, deposited in rapidly sinking troughs (7).
Bai-Hassan Formation (Upper Bakhtiari Formation):
This formation is the youngest one in the
stratigraphic column of the studied region. The Bai-
Hassan Formation is of Middle Pliocene age. It
consists of molasses sediments represented by
deposition of conglomerates and claystone with
some sandstone and siltstones beds. Variations from
claystone to siltstone and sandstone, horizontally and
vertically were observed. The conglomerates are the
first main constituent of the formation, especially in
the upper parts in which they from more than half of
the thickness of this formation. Conglomerates
consist mainly of limestones, silica and some
igneous and metamorphic rocks. The shape of
conglomeratic pebbles is spherical, bladed and rod
shape, the size varies from less than 1cm up to
15cm, sand and calcareous materials poorly cement
the pebbles. Lenses of sandstone are common in the
conglomerates.
The thickness of the formation is difficult to
measure due to wide covered areas of the formations
outcrop. The top of the formation is always
weathered. The lower contact of the formation with
underlying Mukdadiya Formation is diachronous (9);
it is recognized lithologically by the appearance of
the first thick (more than 1m) conglomerate horizon
(10).
The depositional environment of the
formation is continental fluviatial, molasses
deposition which is the product of erosion of the
mountain ranges, deposited in one or more sinking
troughs in front of those ranges.
Quaternary sediments:
Quaternary sediments covered large parts of
the studied area, especially in the south,
southwestern parts of the studied regions. These
sediments represent; River terraces, slope sediments,
valley filling sediments and soil. They differ widely
depending on the type of the mother rocks and on
the order of the valleys that exist in the mountains,
as well as on weathering process.
Structural Analysis of the Mawaran- Mirawa Syncline:
This syncline is relatively narrow and long
one. Extends from Sarqant village at NW plunge,
towards north of the Nazanin town it called wadi
Balessan, it is about 30km length measured on aerial
photographs, all parts of this syncline located within
studied area. The trough of the syncline consist
upper Fars formation with river deposit. The axis
trend N55W from up to near Hasara village, then the
axis deflected to take a direction N35W. In order to
analysis this structure it divided in to two segment
one located at northwestern side which we called it
Mawaran segment and the second portion located at
southeast called Mirawa. Each part has its own
structural characteristic differs from each other;
accordingly we divided in to two part.
A): Mawaran segment of the Syncline:
One of the field traverses located at this part
of this syncline, the stereographic projection for
bedding planes (Fig.5) show different structural
characteristics. The attitude of the southwestern limb
of this syncline is 299/59, while the northeastern
limb have attitude of 124/33, this indicate that the
south western limb is steeper than the northeastern
limb accordingly the vergency of the fold in this
segment is toward northeast direction. The fold axis
(B-axis) in this part measured from stereographic
projection as 300/3. The axial plane attitude is
121/77 and the interlimb angle is measured as 95.
The geological map of this portion of
syncline also show that the amount of the dip in
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southwest limb show higher angle than the
northeastern side, so that the axial plane directed
toward gentler limb that is northeastern limb.
B): Mirawa segment of the syncline:
This part of the major synclinal fold located
towards southeastern side, in this portion also one
traverse is taken, and all bedding plane data were
plotted on the stereographic projection (Fig.6). The
total of 48 bedding planes shows that the attitude of
the southwest limb is 343/32, while the attitude of
the northeast limb of the same syncline in this
segment is 138/51. The axial plane attitude is
328/82, which coincides with the direction of the
south west limb, this means that this syncline in this
portion has vergency towards southwest, which is
differs from the Mawaran segment, as well as the
fold axis has an attitude of 146/11, and the interlimb
angle is about 77. The geological map of this
synclinal fold also shows that the values of dip of
beds are higher in northeast limb rather than the
southwest limb.
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NE Limb of the Mirawa Syncline
SW Limb of the Mirawa Syncline
B-axis
B-axis
SW Limb of the Mawaran Syncline
NE Limb of the Mawaran Syncline
SW limb attitude
NE limb attitude
pi- plane attitude
Attitude of Axial plane
interlimb angle = 86
Fig ( ) : Sterographic projection for bedding planes in MAWARAN section
Fig ( ) : Sterographic projection for bedding planes in MIRAWA section
SW limb attitude
NE limb attitude
attitude of pi- plane
attitude of Axial plane
Interlimb angle=72º
Fig.5
Fig.6
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C): Structure of the Middle part of the Mawaran-
Mirawa Syncline:
(Junction part of the two segments)
The middle part at which the Mawaran segment
changed to Mirawa segment has a characteristic
structural important. This part which is the junction
coledorie between the above two segment are
described in many structural reports and thesis.
Travaglia and Dainelli, (11) Described that a major
lineament pass through this junction, more over
Οmar (5) describe this major lineaments and he
considered to be as one of the regional lineament
which passes through this area, his description are
listed below:
This Lineament (Fig.7) is long regional lineament,
was first delineated on the Landsat mosaic of
Kurdistan region on the basis of aligned northeast
trending topographic and tonal features (11). The
most notable geomorphological and structural
features, which characterize this lineament, are from
southwest to northeast as follow:
Fig.(7): Landsat image show the regional lineament C passing through the studied syncline ( after Omar,2005)
1- Deflection of the Qarachuq
anticlinal fold axis coincides in this part with the
position of a known fault delineated on the
geological map of this anticline (12).
2- Lineament (C) passes
northeastwards through the Kirkuk anticlinal
structure causing culmination and depressions in the
axis of this structure leading to the so-called
Khurmalah, Baba and Avanah domes in the jargon
of local petroleum geologists.
3- In the Arbil plain this Lineament
coincides with straight segments of the surface
drainage pattern as well as, tonal variation is also
noticed along this lineament in this locality.
4- A spectacular topographic
manifestation of lineament is seen in the steep cliffs
of Sara-Rash locality where the Pirmam anticlinal
axis ends abruptly.
5- Deflection of the Mirawa -Mawaran
synclinal axis due to this lineament from the
direction of 320 to 295.
6- Northeastwards, this lineament cuts
a cross the southwestern limb of Shakrok Anticline
where a 35m long dextral strike-slip fault can bee
seen in the field.
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7- The northeastern extension of this
lineament cut a cross successive anticlines of Shikh-
Wasanan and Korak anticlines causing collapse,
gorges and displacements within the different
geological formation
This lineament divides the area into two sub-blocks
(5) , one of the block located to the southeast which
Mirawa part of this synclinal structure is consist,
while the second block located to northwest and
Mawaran segment is a part of it. This major
lineament may be a surface manifestation of the
basement block boundary. The subdivisions of
folded zone into a blocks by basement faults is
propounded by coworkers such as; Numan,(13),
Doski(14).
Our study in the field in this area of that
syncline indicates that this major lineament coincide
with two faults of strike-slip type, one of them
located at NE limb of the synclinal structure which is
of sinistral type and the second one located at SW
limb of same type and on the same extend. The fist
one shows displacement in outcrops for about 10m,
while the second one displaced the beds for about
15m. Moreover some normal and reverse faults of
small displacement ranging 5-7m are present in same
positions. These faults occurs parallel to the
synclinal fold axis, especially in junction part of the
two segments (i.e. Mawaran segment and Mirawa
segment). The normal faults occurs mostly in this
area parallel to bedding planes, so it form bedding
faults, while reverse faults makes an angle to the
bedding plane (see geological map).
Interpretation and Discussion of the results: Previous field observation and data analysis
indicates that this elongate, narrow synclinal
structure made up of two segments, which they are
Mawaran and Mirawa segments. Each segment has
its own structural properties differs from the other
part. One of the most worthwhile points in the
structural analysis is concerning the trend of the fold
axis. The axis of this syncline in Mawaran part has a
trend of 301˚, while Mirawa part of this syncline has
fold axis that trend 146˚ (i.e. 326˚). This indicates
that the same syncline has two different fold axes
direction. The variation between these two trends is
about 26˚, which means that the Mawaran segment
(i.e. fold axis) deflected from Mirawa segment (i.e.
fold axis) by 26˚.
One another notable exception that must take
into consideration is concern the vergency of this
fold. The axial plane of the Mirawa synclinel
segment directed towards northeast, while the axial
plane of the Mawaran synclinal segment directed
towards southwest. This indicates that the axial
plane of this syncline is flip-flopped nearly in the
middle part (i.e. junction part).
The junction between these two segments
appears on landsat image as a major regional type
lineament which has a long length with a direction
nearly N45E. In the field the position of this
lineament occupied by a number of strike-slip,
normal and reverse faults. The two strike slip faults
are considered to be of traversal fault type that cut
the middle part, while the normal and reverse faults
are two longitudinal faults type. All of these faults
seem to be of local occurrence and of restricted
elongation.
Moreover, it seem that the response of each segment
for a regional stresses was different, so reflect
different geometrical characters for each segment.
The hinge closer for Mirawa segment is much tight
than the hinge of the Mawaran segment; this can
obviously appears from two interlimb angles.
The structural model, which is applicable for the
above situation is during regional stress, which acted
on this syncline bending, occurs along a middle part,
which was occupied by a major lineament. This
lineament may relate to a basement fault. The
bending of the syncline create a space in one limb,
and in order to avoid this space problem a set of
strike-slip, normal and reverse fault appears (Fig.8).
These situations obey the model that proceeded by
Twiss and Moores (15). The basement fault may be
a basement block boundary, accordingly each block
behaviors separately with respect to a regional
stresses which acting on them, one of them (such as
Mirawa segment) became much more tighter due to
it located between two rigid cretaceous obstruction
one of them in north which represented by uplifting
of cretaceous succession in Shakrok Anticline, and
another obstruction located in south represented by
Safin cretaceous successions which was uplifted in
that time. Concerning Mawaran segment there are no
any criteria tell about presence of any obstruction
body around this part, so that the syncline in this part
rotated anticlockwise by amount of 26˚, through a
middle part which is the location of major lineament.
This model seems to be a convenient about the area
of the study many coworker in low propounds
especially subdivision of the area into sub-blocks
and high folded zone of the Iraqi territories (14).
Recent Researches in Geography, Geology, Energy, Environment and Biomedicine
ISBN: 978-1-61804-022-0 29
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9-Buday, T., 1980. The regional geology of Iraq,
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10-Sissakian, V. K. and Youkhana, R., 1978. Report
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11-Travagalia, C. and Dainelli, N., 2003. Lineament
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Iraq). Unpub. M.Sc. thesis, University of salahaddin,
129p. 15-Twiss, R. J. and Moores, E. M., 1992.
Structural geology. W.H. Freeman, USA, 532
Recent Researches in Geography, Geology, Energy, Environment and Biomedicine
ISBN: 978-1-61804-022-0 30