(Khanaqin) Fault, Kurdistan Region, Northeast Iraq
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/305979606 Surface analysis and critical review of the Darbandikhan (Khanaqin) fault, Kurdistan Region, Northeast Iraq Article · July 2016 CITATIONS READS 4 363 4 authors, including: Kamal H Karim Salim Hasan Sulaiman (Al-Hakari) University of Sulaimani University of Sulaimani 90 PUBLICATIONS 635 CITATIONS 9 PUBLICATIONS 24 CITATIONS SEE PROFILE SEE PROFILE Polla Khanaqa Kurdistan Institution for Strategic Studies and Scientific Research 50 PUBLICATIONS 95 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Both above (two) articls to me View project Updating geology of Iraqi Kurdistan and Critical review of published data View project All content following this page was uploaded by Polla Khanaqa on 08 August 2016. The user has requested enhancement of the downloaded file. Kurdistan Academics Journal (KAJ), Part - A -, Vol: 12, No.: 1, July 2016 ñŒí¿óm ،1ZòŠbàˆ ،12@ZÊói ،- A-@ð’ói ،(KAJ)@çbn†ŠíØ@ðäbﺆbØó÷@ñŠbÄü 2016 @ Surface analysis and critical review of the Dar- bandikhan (Khanaqin) fault, Kurdistan Re- gion, Northeast Iraq Kamal H. Karim*, Salim H. S. Al- Hakari*, Soran O. A. Kharajiany* and Polla A. Khanaqa** *. Department of Geology, School of Science, Faculty of Science and Science Education, University of Sulaimani, Su- laimaniya, Kurdistan Region, Iraq. **. Professor, PhD in Organic Petrology- Geobiology, Head of Kurdistan Institution for strategic studies and Scientific Research (KISSR), Sulaimaniya, Kurdistan Region, Iraq. Abstract The Iraqi Zagros Mountain Belt has been deformed intensely by colliding of Arabian and Iranian plates and the resulted deformation, on all scales, have been analysed in the previous studies, includ- ing folding and faulting. One of these deformations is the Darbandikhan (or Khanaqin) fault which has nearly N20E tends. According to the previous studies, it extends for about 200kms in the eastern Iraq and nearly coincides with Sirwan (or Diala) river. It is indicated on the maps and described by many authors previously either as traverse strike slip fault or as deep normal fault. Moreover than that, some geologists have attributed many tertiary stratigraphic and sedimentologic variations to the movement of the blocks of this fault. In the present study, the field data and stereonets are used to analyse the surface structural and stratigraphical expression of the fault. For this purpose, the Dar- bandikan Gorge (or town) and its surrounding areas are survey for classification of the deformational and stratigraphical and sedimentologic difference (on the both side of the fault) that may be associ- ated with this fault on the surface. In the present study, neither traverse strike slip nor normal fault are recorded in the Darbandikhan gorge and surrounding areas. Moreover, no stratigraphic differ- ences (facies changes) are recorded on both left and right sides of the assumed fault. The recorded deformation is lateral thrust fault that strikes nearly N20W. The strikes of the fault are not coinciding with the previously indicated Darbandikhan (Khanaqin) fault which is assumed to strikes nearly N20E. In this study the stress components (ϭ1, ϭ2, and ϭ3) are clarified with the origin of the shorten- ing that are associated with the thrust and strike slip faults. Keywords: lateral thrust, oblique strike slip fault, Pila Spi Formation, Zagros Main thrust, Dar- bandikhan town, Sirwan fault, Khanaqin fault. Introduction and classified as Consequent River which The area is located at 55 km to the meets with many subsequent tributaries. The southeast of Sulaimani city and includes the largest tributaries are Dewan, Dara Duwena area around Darbabdikhan town on the both and Zhalla Naw streams which are descend- right (western) and left (eastern) sides of the ing toward the Sirwan River from Qaradagh Sirwan River (upstream of Diala River). Re- and Barkal (northern part of Tuny Baba) and cently, the area has subjected to intense field Zimako areas respectively. In the studied and seismic survey for oil exploration and area, Sirwan River has highly meandering two deep well are drilled but oil has not course which controlled by local structure, found till now. The area is part of the Sirwan lithology and coarse accumulation of allu- valley which collects runoff from most parts vial fan sediments. of northeast of Kurdistan region into Dar- Most areas of the valley consist of lo- bandikhan lake (Fig.1). The Sirwan river cal plains which are hilly and mostly sloping valley has broad bottom with gentle sides gently toward the Diala River. These plains 61 Kurdistan Academics Journal (KAJ), Part - A -, Vol: 12, No.: 1, July 2016 ñŒí¿óm ،1ZòŠbàˆ ،12@ZÊói ،- A-@ð’ói ،(KAJ)@çbn†ŠíØ@ðäbﺆbØó÷@ñŠbÄü 2016 @ are mainly covered by sporadic small and The main mountain of the area is Zim- large blocks of limestone of Pila Spi Forma- nako, Golan and Sagrma which are located tion and Oligocene Rocks such as the area at the north, west and southwest of the Dar- around Darbandikhan town. Other parts of bandikan Dam (Fig.1). The lateral thrusts the areas are covered by badlands which are are exposed directed along the downstream consisted of numerous small valleys and of the latter dam especially at left side of the canyons which are deep and steep sided. Diala River where the six locations are These bad lands occur on the areas that are found where slickensides are found. The aim covered (consists) of conglomerate and red of this study is to surface analysis and criti- clay stone of Upper and Lower Bakhtiari cal review of the Darbandikhan (Khanaqin) Formations. The best examples of these bad fault which is assumed, in the geological lands are the area that is known as of Tuny literature of the Iraq, ass the main geological Baba and the streams of this areas are called deformation in the northeastern Iraq. The locally “Khir” in Kurdish which indicating analysis includes structural and stratigraphi- to accumulation of coarse spherical gravels cal differentiation on both sides of the fault on the stream beds. (Fig.2). Fig. (1): Topographic map of the area around Darbandikhan town shows the two lateral thrusts and bending of the anticlines around the conglomerate successions (indicated by x letters) 62 Kurdistan Academics Journal (KAJ), Part - A -, Vol: 12, No.: 1, July 2016 ñŒí¿óm ،1ZòŠbàˆ ،12@ZÊói ،- A-@ð’ói ،(KAJ)@çbn†ŠíØ@ðäbﺆbØó÷@ñŠbÄü 2016 @ Fig. 2: Tectonic subdivision of the northern Iraq by Jassim and Goff (2006)[1] on which the studied area is shown with, 1, 2 and 3: three fault of the present study, 4: Unclassified fault of Jassim and Goff (2006) [1] 5: strike slip fault of Ibrahim (2009) [2] and Lawa et al. (2013) [3]. Method of the study which resulted from mesolateral thrust and Data collection is depended on the reverse faults are compared with that of the field survey around the Darbandikhan town main Zagros thrust fault to see angular rela- where there are extensive outcrop of the Ter- tion between them. tiary rocks on the both side the assumed Khanaqin fault. During survey the lithol- Stratigraphic expressions on the ogy, boundary, deformational features and both sides of the Khanaqin facies changes of stratigraphic units, on the The stratigraphy of the exposed forma- both sides of the fault, are inspected by hand tions is important for checking of the strati- lenses and eyes. The inspections are re- graphic expressions of the Khanaqin fault corded and compared with the findings of in the area which may be expressed in dif- previous studies. The fault data, strike, dip ference in facies, lithology and their thick- and displacements are measured using geo- ness (Fig.3). The present expressions are logical compass. The method of Richard W. compared with those concluded in many Allmendinger is used for analysis of the data previous studies such as Lawa (2004) [4], for indication of the paleostress using Fault- Ghafur (2012) [5] and Lawa and Ghafur KinWin 1.2.2 Program, 2001. (2015) [6] whom attributed many facies The stereographical representation of change and stratigraphic characteristics to the data is depended on software that plots the Khanaqin fault. the faults and the striations and calculates the attitude of (σ1, σ2 and σ3) and indicates Kolosh Formation (Paleocene) the direction of the footwall and hanging The formation consists of black to wall movement by arrows. The paleostress grey marl, sandstone and thin beds of con- glomerate and its thickness reaches about 63 Kurdistan Academics Journal (KAJ), Part - A -, Vol: 12, No.: 1, July 2016 ñŒí¿óm ،1ZòŠbàˆ ،12@ZÊói ،- A-@ð’ói ،(KAJ)@çbn†ŠíØ@ðäbﺆbØó÷@ñŠbÄü 2016 @ 400m. It is exposed in the core of the anti- [9]. The formation is nearly similar on both cline such as Sagrma, Kalosh and both side of the fault and it rapidly change to Zmnako and Birke and Bamo. Due to the dolomitic limestone and marly limestone of softness, it is intensely deformed by upwards the Khurmala Formation which is de- flow and accumulation in the cores of the scribed by Karim (1997) [10]. above anticlines. The softness has motivated sliding of many blocks of the Sinjar Forma- Pila Spi Formation tion on Kolosh Formation along the north- This formation is directly related to the western limbs of the above anticlines. Due studied faults in the studied area and its to the sliding, the formation has rolling and thickness is about 70 meters. It composed of hummocky surface. These slides are dis- chalky and dolomitic limestone. In the stud- cussed in detail by Karim and Ali (2004) [7] ied area, according to Khanaqa (2012) [11], and Ali (2005) [8] directly to the north of the its lithology contains (in some intervals) in- studied area.