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a): Tectonic Subdivisions of Northern Iraq (Jassim and Goff, 2006) Showing the Studied Area, b): Location of the Studied area in the Zagros Fold-Thrust Belt (Modified from Ghazi and Moazzen, 2015).
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A part of the Govanda Formation is studied in five outcrops from northeastern Iraq near the Iraqi-Iranian borders. It consists of polygenic conglomerates, detrital limestones (conglomeratic limestone), and highly fossiliferous limestones of reef-fore-reef facies with occasional interbedding of terrigenous sediments. Tectonically, the formation is i...
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... studied area belongs to Kurdistan Region, northeastern Iraq in the Sulaimani Governorate near the Iraqi-Iranian borders (Fig.1). The sections of the formation are distributed over six different areas. ...
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... facies is very common in the lower part Bahe section and it occurs rarely in the Qzlja and Barda Balaka sections (Fig.9). This facies consist of skeletons or bioclasts of pelecypods ( Fig.10) with or without coral and red algae fragments (that are larger than sand size) and floated or embedded in fine matrix of sand or silt sized bioclast or lithoclasts. ...
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... facies show crude lamination and alternated with sandy marlstone. In one case and in the Barda Balaka section, there is a sample contain clasts of large gastropod and other unknown fossils (Fig.11). Generally, in this outcrop and its section, the clasts are very angular and the delicate sculptures are clear, which are denoting very short distance of transportation and relatively rapid deposition. ...
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... facies consists of pebble-sized limestone lithoclasts and bioclasts or skeletons of coral, and it is very common in all sections. Coral bioclast rudstone is common in Rashan and Bahe sections, which consists of elongated, 2 -3cm long and 0.3-1cm in diameter (Fig.12). The lithoclast rudstone is very common in Qzlja and Barda Balaka sections and it makes up more than 50% of the thickness of the section (Fig.13). ...
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... bioclast rudstone is common in Rashan and Bahe sections, which consists of elongated, 2 -3cm long and 0.3-1cm in diameter (Fig.12). The lithoclast rudstone is very common in Qzlja and Barda Balaka sections and it makes up more than 50% of the thickness of the section (Fig.13). The lithoclast rudstones are composed of angular to sub-angular pebbles of limestone clasts of different constituents includjng coral or algae or bioclasts or lithoclasts pebbles. ...
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... facies is well-expressed in the sections of Barda Balaka and Qzlja outcrops. It resembles a loose bundle of thin wood sticks of about 0.2-4cm thick and more than 10cm long (Fig.14). It occurs in thick and massive beds of the middle part of the section of Qzlja outcrops. ...
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... occurs in thick and massive beds of the middle part of the section of Qzlja outcrops. The broken and re-deposited fragments of this facies have generated the coral floatstone or rudstone (Fig.12a). ...
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... hand specimen, the red algae coated corals and other grains look like elongated oncoids (Fig.15b) but they are not oncoids due to the fact that red algae excluded from algae that formed stromatolies and oncoids (Scholle and UlmerScholle, 2006). ...
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... hand specimen, the red algae coated corals and other grains look like elongated oncoids (Fig.15b) but they are not oncoids due to the fact that red algae excluded from algae that formed stromatolies and oncoids (Scholle and UlmerScholle, 2006). In many cases, the corals steam and polyps are surrounded and covered by crustose red algae (Figs.15b and c), which might be resulted from the competition between algae and corals on coral reefs as discussed by McCook et al. (2001). ...
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... facies is common in Barda Balaka and Chwarta sections while it is rare in Qzlja and Bahe sections; under hand lens and binocular microscope, it consists mainly of irregular or global bodies (colonies) or patches of pentagonal coral and brain-like corals. The sizes of the colonies or patches are different, but the common one is 5-30cm in diameter (Fig.15a, b). The spaces between patches are filled with fine- grained carbonate (lime mud and fine-grained allochems). Many specimens are found to contain single large corals (mushroom corals) with a diameter of 3 -7 cm, consisting of framestone and associated with red algae (Fig.15a). The present study indicates that this facies is most possibly ...
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... spaces between patches are filled with fine- grained carbonate (lime mud and fine-grained allochems). Many specimens are found to contain single large corals (mushroom corals) with a diameter of 3 -7 cm, consisting of framestone and associated with red algae (Fig.15a). The present study indicates that this facies is most possibly deposited in backreef environment. ...
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... the studied sections and outcrops, this facies is not common, but it exists in all sections especially in Qzlja and Barda Balaka sections. In hand specimen, it can be seen as dense undulated and corrugated laminations that probably represent stromatolites (Fig.16a). In Qzlja section, there is a highly wavy limestone and under stereoscope microscope it shows dense reticulate texture that is made of layers of tiny pillars, which forms brick-like wall structures and are distinctive features of stromatolites (Figs.16b and 17). ...
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... hand specimen, it can be seen as dense undulated and corrugated laminations that probably represent stromatolites (Fig.16a). In Qzlja section, there is a highly wavy limestone and under stereoscope microscope it shows dense reticulate texture that is made of layers of tiny pillars, which forms brick-like wall structures and are distinctive features of stromatolites (Figs.16b and 17). These limestones are stromatoporoids bindstone according to the comparison of the present sample with those published in web site (see http://www.earthsurfaceprocesses.com/3f-E-Stromatojlites Stromatoporoids.html). ...
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... limestone is characterized by the occurrence of various foraminiferas skeletons of in-situ species and in most cases; it is associated with bioclasts of red algae and pelecypods in addition to lithoclasts, but without planktonic forams. There are many species of forams in the Bahe outcrop such as Borelis melo melo and Borelis melo Curdica and unknown miliolids (Figs.18a and b). While those of Mila Kawa outcrop, include different reworked nummulites, lepidocyclina and rotalids species (Fig. 19). ...
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... bioclasts of red algae and pelecypods in addition to lithoclasts, but without planktonic forams. There are many species of forams in the Bahe outcrop such as Borelis melo melo and Borelis melo Curdica and unknown miliolids (Figs.18a and b). While those of Mila Kawa outcrop, include different reworked nummulites, lepidocyclina and rotalids species (Fig. ...
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... consist of limestone clasts that are well sorted and well-rounded allochems bound together by spary calcite cement. They appear transparent under binocular microscope and in some intervals; this facies contains bioclasts (Fig.21a). The facies was deposited in high energy agitating environment in which all the fine grain sediments (lime mud) are washed out. ...
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... Due to the complex tectonics and closing of the Neo-Tethys Ocean, which created separate sub-basins, studies have encountered many challenges in separating these formations. Karim et al., (2018) studied the Govanda Formation in some localities around Penjwen town from the Northeastern Iraq; they stated that the formation is consisted of polygenic conglomerates, detrital limestones and highly fossiliferous limestones of reef-fore-reef facies with terrigenous sediments. ...
The Govanda Formation is cropped out as a patchy pattern and as high ridges between the Zagros Suture and Imbricated Zones of the Fold and Thrust Belt of Iraq. The present study concerned with the detailed study of biostratigraphy of the Govanda Formation in two representative localities in Kurdistan region of Iraq. 107 samples from both sections were collected and described. The formation is dominantly composed of fossiliferous limestones with conglomerate, sandstone and shale. 32 species of benthic, planktonic foraminifers and other miscellaneous fossils identified that used in the biostratigraphic zonation for determining the age of the Govanda Formation. Some species of benthic and planktonic foraminifers were identified here in the formation have not recorded previously such as Elphidium sp.14, Meanderopsina iranica, Dendritina rangi, Globorotalia archemenardi-Globigerinoides trilobus, Orbulina universa, Quinquiloculina sp., Pyrgo bulloides, Triloculina sp., Ammonia baccari, Austrotrillina howchini, Austrotrillina asmariensis, Miogypsina tani and Miogypsinoides sivasensis. Based on the recognition and distribution of the foraminiferal species in the Govanda Formation, three assemblage zones were identified, they are a) Austrotrillina howchini- Miogypsina-Miogypsinoides-Peneroplis evolutus-Peneroplis farsensis Assemblage Zone of the Aquitanian age. b) Borelis melo melo-Borelis melo curdica-Meanderopsina iranica-Elphidium sp.14 Assemblage Zone of the Burdigalian age. c) new-recognized Assemblage Zone in this study that comprises Globorotalia archemenardi-Globigerinoides trilobus-Orbulina universa Assemblage Zone of the Langhian age. According to the described zones and fossil contents, the biostratigraphic analysis indicates that the age of the Govanda Formation is Early-Middle Miocene (Aquitanian-Langhian).
... Directly to the northeast of this outcrop, the greywacke of the latter formation is pulverized and serpentinite which was previously ascribed to Ophiolite rocks. This outcrop is considered Middle Miocene Govanda Formation by Karim et al. (2018) [42] but they admitted that it contained reworked Eocene nummulites. ...
... Therefore, the present study considers the two formations as a pure sedimentary succession of clastic and carbonate facies deposited in the Paleocene-Eocene foreland basin. Previously, Ali et al. (2013[4] and 2017) [17] and Aswad et al. (2016) [41] and (2011, p.815) [43] (put the deposition of the two formations (groups) in the back-arc and Island arc settings (Fig.7). E. a, b, c) photographed on the outcrop that is shown in fig.8. ...
The previous studies documented the tectonics setting, petrology, and geochemistry of the Penjween area (with Shalair Valley) before 70 years and considered it as an area of igneous rocks, and tectonically composed of three thrust sheets. According to these studies, the area includes two main igneous rock units: The Penjween Ophiolite Complex comprised of gabbro, peridotite, and granitoid intrusions at the south. The second unit is Kata Rash Volcanic rocks (Kata Rash conglomerate of the present study) which are located in the north and northeast and comprised of mafic, intermediate and felsic volcanic rocks. The present study disagrees with the previous documentation of these rocks and changed the claimed Kata Rash Volcanic Rocks and Penjween Ophiolite to metamorphosed conglomerates and coarse sandstones of the proximal facies that belong to metamorphosed sediments of Walash Formation (or Group) that was deposited in a large Paleocene Foreland Basin. The Walash Group and Kolosh Formation (as unmetamorphosed, coarse and fine sandstones or greywackes) were deposited as deep basin distal facies in the basin while Kata Rash Conglomerate belongs to coastal facies. All the above five units are deposited by turbidity currents during Paleocene-Eocene and they correlated, in the present study, stratigraphically along the basin paleodip from the present location of the Shalair valley to the south of Sulaymaniyah City. The Naopurdan Formation is recognized for the first time in the Penjween area and its facies and foraminifera are documented and correlated with Sinjar Formation. The above siliciclastic sediments were derived from volcanic source areas inside Iran and depending on the field, lab, and evaluations of the previous studies, the present study drew sedimentary stratigraphic columns and cross-sections for the Penjween and Sulaimanyiah areas and correlated their units along 100 km across the latter two areas. The correlation linked the Kolosh Formation with stratigraphic units of the Penjween area for the first-time supposing deposition during Paleocene-Eocene and sharing the same foreland basin which is aided by the first record of the occurrence of the Kolosh Formation in Chwarta by nannofossils and petrography.
... In this research, the distribution of benthic and planktonic foraminifera with miscellaneous fossils in the Govanda Formation is used as a tool for paleoenvironmental implications. . According to [64] the depositional environment of the Govanda Formation in Penjwen area was high energy, shallow and normal-marine sea which consists of fore-reef, reef and back-reef. [65] Have identified the depositional environment of the Govanda Formation as reef, fore-reef, back-reef depending on the microfacies analysis. ...
The Govanda Formation was deposited during the Early-Middle Miocene Epoch in the intermountain areas between Zagros Suture and Imbricate zones. The Paleoecology and depositional environment of the Govanda Formation has been studied in detail in Mergasor and Penjwen districts for the first time. The formation in these two sections from bottom to top is comprised of thick bedded, oyster and chert bearing conglomerate, pebbly sandstone, red-brown shale and siltstone, fossiliferous limestone and detrital limestone. The formation in Mergasor, Beshkariya Village is 85 m thick and in Penjwen, Gole Village is 60 m thick. The study is based on the detailed microscopic analysis on the benthic and planktonic foraminifera with miscellaneous fossils that exists in the carbonate rocks of the Govanda Formation. Larger and smaller benthic foraminifera include the following genera: Operculina sp., Borelis melo sp., Austrotrilina sp., Peneroplis sp., Meanderopsina sp., Miogypsinoids and Miogypsina sp., Archaias sp., Amphistegina sp., Textularia sp., Lepidocyclina sp., Miliolids, Quenquiloculina sp., Pyrgo sp., Spiroloculina sp., Triloculina sp., Ammonia sp., Elphidium sp., Dendritina sp. and Rotalia venoti dominated the limestones of the Govanda Formation. Planktonic foraminifers are mostly includes the following genera: Globigerinoids sp., Globigerina sp., Globorotalia sp. and Orbulina sp. Moreover, miscellaneous fossils include corals, coralline red algae, echinoderms, bivalves, ostracods, bryozoans, brachiopods and serpulid worms (Ditrupa sp.). The paleoecological condition of the formation was interpreted as follow; the temperature of the Govanda basin ranges between 15-30 °C, nutrient level is between eutrophic to mesotrophic, salinity ranged between normal saline to hypersaline water, light intensity ranging from euphotic to mesophotic and less oligophotic zones, the water depths ranged between 0-120 m, the clastic influx was high in the basin, differences in size and shape within foraminifers of the Govanda Formation indicate various depositional environments and ecological conditions, the water energy was moderate. The environment of deposition is interpreted as being ramp environment. Depending on the different microfauna that exist in the formation, four main zones are distinguished in the ramp model of the Govanda Formation as follows; proximal inner ramp setting which includes open lagoon, distal inner ramp setting which includes back-reef environment, proximal middle ramp setting which includes reef and fore-reef environments, distal middle ramp/ proximal outer ramp setting, which includes open marine environment.
... In this research, the distribution of benthic and planktonic foraminifera with miscellaneous fossils in the Govanda Formation is used as a tool for paleoenvironmental implications. . According to [64] the depositional environment of the Govanda Formation in Penjwen area was high energy, shallow and normal-marine sea which consists of fore-reef, reef and back-reef. [65] Have identified the depositional environment of the Govanda Formation as reef, fore-reef, back-reef depending on the microfacies analysis. ...
The Govanda Formation was deposited during the Early-Middle Miocene Epoch in the intermountain areas between Zagros Suture and Imbricate zones. The Paleoecology and depositional environment of the Govanda Formation has been studied in detail in Mergasor and Penjwen districts for the first time. The formation in these two sections from bottom to top is comprised of thick bedded, oyster and chert bearing conglomerate, pebbly sandstone, red-brown shale and siltstone, fossiliferous limestone and detrital limestone. The formation in Mergasor, Beshkariya Village is 85 m thick and in Penjwen, Gole Village is 60 m thick. The study is based on the detailed microscopic analysis on the benthic and planktonic foraminifera with miscellaneous fossils that exists in the carbonate rocks of the Govanda Formation. Larger and smaller benthic foraminifera include the following genera: Operculina sp., Borelis melo sp., Austrotrilina sp., Peneroplis sp., Meanderopsina sp., Miogypsinoids and Miogypsina sp., Archaias sp., Amphistegina sp., Textularia sp., Lepidocyclina sp., Miliolids, Quenquiloculina sp., Pyrgo sp., Spiroloculina sp., Triloculina sp., Ammonia sp., Elphidium sp., Dendritina sp. and Rotalia venoti dominated the limestones of the Govanda Formation. Planktonic foraminifers are mostly includes the following genera: Globigerinoids sp., Globigerina sp., Globorotalia sp. and Orbulina sp. Moreover, miscellaneous fossils include corals, coralline red algae, echinoderms, bivalves, ostracods, bryozoans, brachiopods and serpulid worms (Ditrupa sp.). The paleoecological condition of the formation was interpreted as follow; the temperature of the Govanda basin ranges between 15-30 °C, nutrient level is between eutrophic to mesotrophic, salinity ranged between normal saline to hypersaline water, light intensity ranging from euphotic to mesophotic and less oligophotic zones, the water depths ranged between 0-120 m, the clastic influx was high in the basin, differences in size and shape within foraminifers of the Govanda Formation indicate various depositional environments and ecological conditions, the water energy was moderate. The environment of deposition is interpreted as being ramp environment. Depending on the different microfauna that exist in the formation, four main zones are distinguished in the ramp model of the Govanda Formation as follows; proximal inner ramp setting which includes open lagoon, distal inner ramp setting which includes back-reef environment, proximal middle ramp setting which includes reef and fore-reef environments, distal middle ramp/ proximal outer ramp setting, which includes open marine environment.
... Despite the previous lithology a chocolate limestone beds contacted with the GPB have been found. Although, [5] described these limestone beds in Gole village as chocolate brown recrystallized limestone and like those seen in Walash group, the authors believed that the limestone bed is return to Govanda Limestone Formation [15]. ...
... Although [15] concluded that the studied area was an intercontinental shallow basin by studying stratigraphy of Govanda Formation, the authors also tend to use morphological features like (vesicles and pipe vesicles diameter size and distributions as well as pillow forms and sizes) and compared to the studies of [29]; [30]; [18]; [4] and all indications point that the GPB extruded in a shallow marine environments with a depth of about less than 350m. Below we consider the implications of the new data we have presented and our new results regarding GPBs to interpret the petrogenesis and tectonic settings in which the GPB rocks formed. ...
The petrological, morphometric and geochemical analyses of pillow lava from Gole village (Penjween town) Sulaimani city Northeastern Iraq have been undertaken. The Gole Pillow basalt (GPB) extruded, in the form of pillow and sheet flow into the Qulqula radiolarite Formation. The basaltic intrusion restricted to a small area of about 100 m2 within Penjween- Walash zone in the Zagros Suture Zone (ZSZ) of Iraq. The investigated area divided into two sections GPB1 and GPB2. It is envisaged that the studied area distinct two episodes of submarine alkaline eruptions that produced pillowed lavas that differently interacted with seawater to produce different morphologies and geochemistries. The pillows of the GPB1 section well exposed all along the Shalair river near Gole village. Although the pillows of the GPB2 section altered due to low-grade metamorphism and late hydrothermal processes, their igneous textures are still preserved. GPB samples are mostly phyric in nature and show porphyritic or sub-ophitic textures. Petrographically, most of the GPB rock samples appeared as amygdaloidal and vesicular aphanitic basalt. Large phenocryst of hypersthene with schiller structure is present within a matrix of longer quenched plagioclase. Numerous small euhedral grains of opaque minerals like ilmenite and hematite are dispersed in the fine groundmass. Morphological features show that the GPB appeared as spheroidal and lobate to tubular individual pillows. Although some pillow extends 2 meters with a foreset distribution some others show cracked with irregularly jointed surface and larger vesicles partly filled with calcite and quartz. Geochemical investigation of GPB exhibit high TiO2 (3.42 – 3.84 wt.%), Fe2O3 (14.84–19.93 wt.%), and high Zr/Nb and Zr/Y ratios respectively (5.85 – 7.2) (7.10-11.40). The content of alkalies, with the Nb/Y ratio≥1.4, and silica, as well as many trace element discrimination diagrams, classify the GPB as alkaline basalts. The field, stratigraphic relationships, and geochemistry of the GPB and associated clastic and carbonate sediments suggest that the pillow lavas were emplaced in a shallow marine marginal within plate basin. The overall geochemistry of GPB resembles that of alkaline basalts generated in within-plate ocean island settings (OIB-type). https://doi.org/10.25130/tjps.v24i7.460
... It has gradational (conformable) boundaries with underlying Kolosh and overlaying Gercus Formations. The Khurmala Formation is less than 10m thick in this area, this reduced thickness may be due to its lateral facies change to Gercus Formation which concluded by Karim et al. (2018, p.53) [13] in Darbandikhan area. ...
... This isolation most possibly attributed to subsidence of hinterland and generation of local basin. In this connection, Karim et al (2018) [18] studied Govanda Formation in the Thrust Zone near the border with Iran in Penjween area and concluded its deposition in a normal marine basin that developed during Eocene and expanded during Miocene. The most serious challenge to the tectonic timing (arrival of tectonic stress) at the studied area is what concluded by Numan et al. (1998) [23] who summarized development of two conjugated tectonic syn-sedimentary joints in the Pila Spi Formation (Middle Eocene-Late Eocene) in the Low Folded Zone in the Mosul Governorate. ...
The previous studies referred to the Duhok area as a terrestrial uplift during Oligocene while the present study achieved completely different result by recording and mapping about 20-30 meters thick succession of the Oligocene Rocks (Kirkuk Group) for first time. The succession extends for about 20 kilometers inside the High Folded Zone and the previous basin boundary of Oligocene shifted to north for more than 50 kilometers. The succession consists of lagoonal limestone and changes in certain places in the north to patchy reef. Few beds of polymictic and limestone conglomerates intervened the succession. The Middle and Upper Oligocene index fossils are common, the most significant ones are Archias hensoni, Austrotrillina howchini, Praerhapydionina delicata, Peneroplis evolutus, Archias asmariensis, Archias kirkukensis and spirolina austrica. The main facies are coral and red algae boundstone, foraminifera and intraclast packstone to grainstone, pelecypod gastropod bioclast packstone to grainstone. The paleogeography setting (model) of the Oligocene is discussed in detail, compared with the previous model and a new model is drawn
... It has gradational (conformable) boundaries with underlying Kolosh and overlaying Gercus Formations. The Khurmala Formation is less than 10m thick in this area, this reduced thickness may be due to its lateral facies change to the Gercus Formation which concluded by Karim et al. (2018, p.53) [13] in the Darbandikhan area. ...
... This isolation most possibly attributed to subsidence of hinterland and generation of local basin. In this connection Karim et al (2018) [18] studied Govanda Formation in the Thrust Zone near the border with Iran in Penjween area and concluded that it deposited in a normal marine basin that developed during Eocene and expanded during Miocene. ...
... .(13). Oligocene fossils in the Kirkuk Group in the Duhok area, a) Peneroplis evolutus, b) Archias asmariensis, s.n.G6,ppl c) Archias kirkukensis (upper left) and spirolina austrica. ...
The previous studies referred to the Duhok area as a terrestrial uplift during Oligocene while the present study achieved completely different result by recording and mapping about 20-30 meters thick succession of the Oligocene Rocks (Kirkuk Group) for first time. The succession extends for about 20 kilometers in side High Folded Zone and the previous basin boundary of Oligocene shifted to north for more than 50 kilometers. The succession consists of lagoonal limestone and changes in certain places in the north to patchy reef. Few beds of polymictic and limestone conglomerates mediated the succession. The Middle and Upper Oligocene index fossils are common, the most significant ones are Archias hensoni, Austrotrillina howchini, Praerhapydionina delicata, Peneroplis evolutus, Archias asmariensis, Archias kirkukensis and spirolina austrica. The main facies are coral and red algae bounstone, foraminifera and intraclast packstone to grainstone, pelecypod gastropod bioclast packstone to grainstone. The paleogeography setting (model) of the Oligocene is discussed in detail, compared with previous model and new model is drawn
Avroman Mountain has a northwest–southeast trend of Zagros Collisional Belt and elongates parallel to the Iranian border in Northeastern Iraq, Kurdistan Region. Previous studies found many volcanic bodies on the mountain and considered them either as Triassic and Cretaceous dismembered ophiolite fragments or as basaltic dykes. The present work focused on the restudy of these bodies and proved that they are neither dykes nor ophiolite rocks. On the contrary, the present study considers these bodies as successions of altered volcaniclastic sandstones (greywackes) and conglomerates that were transported from the Urumieh-Dokhtar Magmatic Arc (UDMA) as fresh or old reworked sediments, during Paleocene–Eocene, and deposited inside the Sanandij-Sirjan Zone (SSZ). Additionally, many clues are found that manifest their sedimentary origins such as presences of laminations, a southward decrease in grain sizes, the parallelism of all the bodies to the surrounding layer of Qulqula Radiolarian Formation (QRF) and Avroman Formation, folded successions, graded beddings, poorly sorted textures, irregular and broken grains outlines, a gradation from conglomerate to sandstone. Other evidences are absences of pillow basalts, amygdales, volcanic vents or cones, volcanic mineralizations, volcanic flow structures and textures, chilled borders, contact metamorphism, sedimentary xenoliths, volcanic bombs, or lapilli, and crosscutting relations between the sedimentary bodies and host rocks. These bodies are nearly located between the Avroman and Qulqula Radiolarian formations at the top and the base, respectively. Finally, these bodies have tectonic, depositional, and chronological close relations with the volcaniclastic successions of the Mawat, Bulfat, and Penjween areas. Stratigraphically, they belong to Walash Formation (or Group) and were deposited during the Paleocene–Eocene.
