scholarly journals Geological, Mineralogical and Geochemical Studies of Kolosh Formation, Dokan Area, Kurdistan Region, Iraq

2021 ◽  
Vol 05 (1) ◽  
pp. 39-49
Author(s):  
Adnan Q. Mahdi ◽  
A. S. Alshami ◽  
A. H. Mohammad ◽  
A. M. Al Tarif
Keyword(s):  
Kurdistan Region ◽  
Carbonate Facies ◽  
Shallow Marine ◽  
Northern Iraq ◽  
Marine Sedimentation ◽  
Geochemical Study ◽  
Geochemical Studies

The geology, mineralogy and geochemical of The Kolosh Formation in Dokan area, northern Iraq has been studied. The formation sequence includes gray and dark gray marl that alternate from clastic submarine sediments represented by turbid deposits resulted from the last stages of the collision movement between the continental plates. The geochemical study showed that the Kolosh Formation is mainly dominated by detrital sediments (Clay) with a dominance of kaolinite illite, and albite wıth low amounts of quartz. The analysis revealed that the Kolosh Formation is dominated by relatively marginal marine sedimentation where shelf bay facies was deposited with carbonate facies deposited as shallow marine. In contrast, SiO2 is strongly negatively correlated with CaO and MgO, this supports their derivation from terrigenous sources during the deposition of Kolosh sediments. Keywords: Kolosh Formation, sequences, mineralogy, geochemistry.

Cretaceous (Aptian-Maastrichtian) stratigraphy of the Shiranish Islam area, northern Iraq

Stratigraphy ◽  
2021 ◽  
pp. 29-70
Author(s):  
Stephen R. Packer ◽  
Kathryn L. Canner ◽  
Ali Chalabi
Keyword(s):  
Analytical Data ◽  
Middle Part ◽  
Kurdistan Region ◽  
Clastic Material ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Northern Iraq ◽  
Faunal Succession ◽  
World Class ◽  
Early Late

ABSTRACT: The Kurdistan region of northern Iraq contains world-class outcrops that make it possible to examine the Cretaceous deep and shallow marine Tethyan faunal succession. Six separate sections covering the Shiranish, Bekhme, Mergi and Qamchuqa formations have been investigated in this study from the Shiranish Islam area. A number of papers have been published on this area, but no comprehensive biostratigraphic record has been published that fully documents the Cretaceous stratigraphy and the chronostratigraphic interpretation of the succession. As a result, this has led to significant lithostratigraphic and chronostratigraphic uncertainties. The upper part of the Qamchuqa is pervasively dolomitized. Rare occurrences of foraminifera are found in less dolomitized intervals in thin-section indicating an early - middle Albian age for the top of the formation. A thin interval comprising the Gir Bir Formation is Cenomanian in age and is present between the top of the Qamchuqa Formation and the overlying conglomerate. Historical studies indicate that the Turonian Mergi Formation occurs between the Qamchuqa and Bekhme formations, but our field and analytical data does not support it as a discrete lithostratigraphic entity, as Turonian aged faunas were not recognized. The conglomerate separating the top of the Gir Bir and base of the Bekhme is subdivided into three units (A, B & C). Units A and B are late Cenomanian to early Turonian age, whilst Unit C is of Campanian age. A significant hiatus separates the Gir Bir and the Bekhme, which encompasses the intra Turonian to Santonian. The limestone facies of the lower part of the Bekhme Formation contains rich benthic foraminiferal faunas (miliolids, Pseudedomia, Cuneolina) of early - early middle Campanian age. This lower - lower middle Campanian section at Shiranish Islam is considered to be equivalent of the upper part of the Sa'di Formation in central Iraq and is therefore re-assigned on the basis of chronostratigraphic attribution to the Sa'di (equivalent) herein. The top of the early - early middle Campanian biofacies is abruptly truncated by an omission surface, marked by an erosive base, an influx of clastic material and a major up-section biofacies change characterized by an influx of Pseudosiderolites and Orbitoides representing an intra-Campanian hiatus. The bioevent sequence suggests that this hiatus at Shiranish Islam comprises at least the middle Campanian (upper part of the G. elevata Zone) into the late Campanian (intra R. calcarata Zone), from approximately 80.64 Ma to 76.09 Ma with 4.55 my missing. The middle part of the Bekhme Formation comprising the Pseudosiderolites - Orbitoides facies is thin (c. three meters) and is re-assigned to the Lower Bekhme Member. The boundary between the Lower Bekhme Member and the Upper Bekhme Member is conformable and marked by a gradual up-section reduction in the size and presence of larger benthic foraminifera (Orbitoides, Pseudosiderolites) and an increase in the planktic component (small planktics and calcispheres). This trend of gradually increasing water depth continues into the Shiranish Formation, with no apparent major breaks in deposition. The Campanian - Maastrichtian boundary falls within Unit A of the Shiranish Formation. Deposition of the Shiranish continued into the earliest late Maastrichtian and is unconformably overlain by the Danian Kolosh Formation. The hiatus between the top of the Cretaceous and the Paleocene extends from the early late Maastrichtian (c. 68.86 Ma) to the upper part of the Danian (62.2 Ma) with an estimated duration of 6.66 my.

THE LATER PREHISTORY OF THE SHAHRIZOR PLAIN, KURDISTAN REGION OF IRAQ: FURTHER INVESTIGATIONS AT GURGA CHIYA AND TEPE MARANI

Iraq ◽  
2020 ◽  
Vol 82 ◽  
pp. 41-71
Author(s):  
Robert Carter ◽  
David Wengrow ◽  
Saber Ahmed Saber ◽  
Sami Jamil Hamarashi ◽  
Mary Shepperson ◽  
...  
Keyword(s):  
Material Culture ◽  
Environmental Data ◽  
Kurdistan Region ◽  
Ceramic Assemblage ◽  
Radiocarbon Dates ◽  
Northern Iraq ◽  
Halaf Period ◽  
Adjacent Site ◽  
Related Series ◽  
Southern Iraq

The Shahrizor Prehistory Project has targeted prehistoric levels of the Late Ubaid and Late Chalcolithic 4 (LC4; Late Middle Uruk) periods at Gurga Chiya (Shahrizor, Kurdistan region of northern Iraq), along with the Halaf period at the adjacent site of Tepe Marani. Excavations at the latter have produced new dietary and environmental data for the sixth millennium B.C. in the region, while at Gurga Chiya part of a burned Late Ubaid tripartite house was excavated. This has yielded a promising archaeobotanical assemblage and established a benchmark ceramic assemblage for the Shahrizor Plain, which is closely comparable to material known from Tell Madhhur in the Hamrin valley. The related series of radiocarbon dates gives significant new insights into the divergent timing of the Late Ubaid and early LC in northern and southern Mesopotamia. In the following occupation horizon, a ceramic assemblage closely aligned to the southern Middle Uruk indicates convergence of material culture with central and southern Iraq as early as the LC4 period. Combined with data for the appearance of Early Uruk elements at sites in the adjacent Qara Dagh region, this hints at long-term co-development of material culture during the fourth millennium B.C. in southeastern Iraqi Kurdistan and central and southern Iraq, potentially questioning the model of expansion or colonialism from the south.

scholarly journals New records of basidiomycetous macrofugi from Kurdistan region - Northern Iraq

2017 ◽  
Vol 11 (6) ◽  
pp. 209-219
Author(s):  
Q. Suliaman Sara ◽  
O. AL- Khesraji Talib ◽  
A. Hassan Abdullah
Keyword(s):  
New Records ◽  
Kurdistan Region ◽  
Northern Iraq

Geochemical evidence of tropical cyclone controls on shallow-marine sedimentation (Pliocene, Taiwan) 

2021 ◽  
Author(s):  
Shahin Dashtgard ◽  
Ludvig Löwemark ◽  
Pei-Ling Wang ◽  
Romy Setiaji ◽  
Yu-Yen Pan ◽  
...  
Keyword(s):  
Foreland Basin ◽  
Extreme Weather ◽  
Extreme Weather Events ◽  
Shallow Marine ◽  
Sediment Reworking ◽  
Virtual Absence ◽  
Marine Strata ◽  
Marine Sedimentation ◽  
Weather Events ◽  
Waves And Tides

<p> Shallow-marine sediment typically contains a mix of marine and terrestrial organic mate­rial (OM). Most terrestrial OM enters the ocean through rivers, and marine OM is incorpo­rated into the sediment through both suspension settling of marine plankton and sediment reworking by tides and waves under fairweather conditions. River-derived terrestrial OM is delivered year-round, although sediment and OM delivery from rivers is typically highest during extreme weather events that impact river catchments. In Taiwan, tropical cyclones (TCs) are the dominant extreme weather event, and 75% of all sediment delivered to the surrounding ocean occurs during TCs.</p><p>Lower Pliocene shallow-marine sedimentary strata in the Western Foreland Basin of Taiwan comprises mainly completely bioturbated intervals that transi­tion upward into strata dominated by tidally generated sedimentary structures, indicating extensive sediment reworking under fairweather conditions. Physical evidence of storm deposition is limited. However, lower Pliocene strata contain OM that is effectively 100% terrestrial OM in sediment that accumulated in estimated water depths <35 m. The overwhelming contribution of terrestrially sourced OM is attributed to the dominance of TCs on sedimentation, whereby ∼600,000 TCs are estimated to have impacted Taiwan during accumulation of a ~200 m long succession. In contrast, the virtual absence of marine OM indicates that organic contributions from suspension settling of marine OM is negligible regardless of the preserved evidence of extensive reworking via fairweather processes (i.e., waves and tides). These data suggest that (1) even in the absence of physical expressions of storm deposition, TCs still completely dominate sedimentation in shallow-marine environments, and (2) the organic geochemical signal of preserved shallow-marine strata is not reflective of day-to-day depositional conditions in the environment.</p>

Geochemical evidence of tropical cyclone controls on shallow-marine sedimentation (Pliocene, Taiwan)

Geology ◽  
2021 ◽  
Author(s):  
Shahin E. Dashtgard ◽  
Ludvig Löwemark ◽  
Pei-Ling Wang ◽  
Romy A. Setiaji ◽  
Romain Vaucher
Keyword(s):  
Foreland Basin ◽  
Weather Conditions ◽  
Extreme Weather ◽  
Extreme Weather Events ◽  
Fair Weather ◽  
Shallow Marine ◽  
Sediment Reworking ◽  
Virtual Absence ◽  
Marine Strata ◽  
Marine Sedimentation

Shallow-marine sediment typically contains a mix of marine and terrestrial organic material (OM). Most terrestrial OM enters the ocean through rivers, and marine OM is incorporated into the sediment through both suspension settling of marine plankton and sediment reworking by tides and waves under fair-weather conditions. River-derived terrestrial OM is delivered year-round, although sediment and OM delivery from rivers is typically highest during extreme weather events that impact river catchments. In Taiwan, tropical cyclones (TCs) are the dominant extreme weather event, and 75% of all sediment delivered to the surrounding ocean occurs during TCs. Distinguishing between sediment deposited during TCs and that redistributed by tides and waves during fair-weather conditions can be approximated using δ13Corg values and C:N ratios of OM. Lower Pliocene shallow-marine sedimentary strata in the Western Foreland Basin of Taiwan rarely exhibit physical evidence of storm-dominated deposition. Instead they comprise completely bioturbated intervals that transition upward into strata dominated by tidally generated sedimentary structures, indicating extensive sediment reworking under fair-weather conditions. However, these strata contain OM that is effectively 100% terrestrial OM in sediment that accumulated in estimated water depths <35 m. The overwhelming contribution of terrestrially sourced OM is attributed to the dominance of TCs on sedimentation, whereby ~600,000 TCs are estimated to have impacted Taiwan during accumulation of the succession. In contrast, the virtual absence of marine OM indicates that organic contributions from suspension settling of marine OM is negligible regardless of the preserved evidence of extensive reworking under fair-weather conditions. These data suggest that (1) even in the absence of physical expressions of storm deposition, TCs still completely dominate sedimentation in shallow-marine environments, and (2) the organic geochemical signal of preserved shallow-marine strata is not reflective of day-to-day depositional conditions in the environment.

scholarly journals Lithostratigraphic and allostratigraphic framework of the Cambrian–Ordovician Potsdam Group and correlations across Early Paleozoic southern Laurentia

2017 ◽  
Vol 54 (5) ◽  
pp. 550-585 ◽  
Author(s):  
David G. Lowe ◽  
R.W.C. Arnott ◽  
Godfrey S. Nowlan ◽  
A.D. McCracken
Keyword(s):  
Climate Change ◽  
Early Paleozoic ◽  
Middle Cambrian ◽  
Shallow Marine ◽  
Upper Cambrian ◽  
Subaerial Exposure ◽  
Marine Sedimentation ◽  
Lower Ordovician ◽  
Fluvial Sedimentation ◽  
Mixed Carbonate

The Potsdam Group is a Cambrian to Lower Ordovician siliciclastic unit that crops out along the southeastern margins of the Ottawa graben. From its base upward, the Potsdam consists of the Ausable, Hannawa Falls, and Keeseville formations. In addition, the Potsdam is subdivided into three allounits: allounit 1 comprises the Ausable and Hannawa Falls, and allounits 2 and 3, respectively, the lower and upper parts of the Keeseville. Allounit 1 records Early to Middle Cambrian syn-rift arkosic fluvial sedimentation (Ausable Formation) with interfingering mudstone, arkose, and dolostone of the marine Altona Member recording transgression of the easternmost part of the Ottawa graben. Rift sedimentation was followed by a Middle Cambrian climate change resulting in local quartzose aeolian sedimentation (Hannawa Falls Formation). Allounit 1 sedimentation termination coincided with latest(?) Middle Cambrian tectonic reactivation of parts of the Ottawa graben. Allounit 2 (lower Keeseville) records mainly Upper Cambrian quartzose fluvial sedimentation, with transgression of the northern Ottawa graben resulting in deposition of mixed carbonate–siliciclastic strata of the marine Rivière Aux Outardes Member. Sedimentation was then terminated by an earliest Ordovician regression and unconformity development. Allounit 3 (upper Keeseville) records diachronous transgression across the Ottawa graben that by the Arenigian culminated in mixed carbonate–siliciclastic, shallow marine sedimentation (Theresa Formation). The contact separating the Potsdam Group and Theresa Formation is conformable, except locally in parts of the northern Ottawa graben where the presence of localized islands and (or) coastal salients resulted in subaerial exposure and erosion of the uppermost Potsdam strata, and accordingly unconformity development.

Batocrinidae (Crinoidea) from the Lower Mississippian (lower Viséan) Fort Payne Formation of Kentucky, Tennessee, and Alabama: systematics, geographic occurrences, and facies distribution

2018 ◽  
Vol 92 (4) ◽  
pp. 681-712
Author(s):  
William I. Ausich ◽  
Elizabeth C. Rhenberg ◽  
David L. Meyer
Keyword(s):  
Shallow Water ◽  
Deep Water ◽  
Dominant Species ◽  
Carbonate Facies ◽  
Shallow Marine ◽  
First Time ◽  
Water Carbonate ◽  
Shallow Water Carbonate ◽  
Water Facies ◽  
Mixed Carbonate

AbstractThe Batocrinidae are characteristic faunal elements in Lower Mississippian shallow-marine settings in North America. Recent delineation of objectively defined genera allows a reexamination of batocrinid species and their distribution in the Fort Payne Formation (early Viséan, late Osagean), a well-studied array of carbonate and siliciclastic facies. The Fort Payne batocrinid fauna has 14 species assigned to six genera, plus hybrid specimens.Magnuscrinus spinosus(Miller and Gurley, 1895a) is reassigned to its original placement inEretmocrinus. Hybrid specimens (Ausich and Meyer, 1994) are regarded asEretmocrinus magnificus×Eretmocrinus spinosus.Macrocrinus casualisis the dominant species ofMacrocrinusin the Fort Payne, andM.mundulusandM.strotobasilarisare recognized in the Fort Payne Formation for the first time.Magnuscrinus cumberlandensisn. sp. is named, 13 species are designated as junior synonyms, the name for the hybrid specimens is changed toEretmocrinus magnificus×Eretmocrinus spinosus, and the previous occurrences of two species in the Fort Payne are rejected. The Eastern Interior Seaway was a mixed carbonate-siliciclastic setting with both shallow- and deep-water epicontinental sea facies ranging from relatively shallow autochthonous green shales to deep-water turbidite facies.Dizygocrinuswas restricted to shallow-water carbonate and siliciclastic facies,Eutrochocrinuswas restricted to shallow-water carbonate facies, andMagnuscrinuswas restricted to deep-water facies. Species distributions varied fromAbatocrinus steropes,Alloprosallocrinus conicus,Macrocrinus mundulus, andUperocrinus nashvillae, which occurred throughout the Eastern Interior Seaway, to species that were restricted to a single facies.Eretmocrinus magnificus,Alloprosallocrinus conicus, andUperocrinus robustuswere the dominant batocrinids in the Fort Payne Formation.UUID:http://zoobank.org/703aafd8-4c73-4edc-9870-e2356e2d28b8

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