Iraqi Bulletin of Geology and Mining

Late Paleocene – early Middle Eocene shallow-water larger benthic foraminifera were identified from the Sinjar Formation that crops out in the southwest of Sulaimaniyah city, northeast Iraq. The present study is applied in an area extremely rich in paleofauna, mainly represented by larger benthic foraminifera. Three sections were studied: Section 1 (75 m thick) and section 2 (135 m thick) in Baranan Mountain, near Qazan and Hazar Merd villages, respectively, whereas section 3 (62 m thick) is in Qara Dagh Mountain, near Sulekan village. In total 461 samples were collected representing all lithological changes along the three sections, and 492 thin sections were prepared and studied under binocular microscope.

The benthic foraminiferal association documented in the study area belongs to 16 families. Thirty genus and twenty five species have been identified. Based on the identified species of larger foraminiferal assemblages, the age of Selandian – Lutetian is assigned to the Sinjar Formation, in the studied area.

Nineteen species of calcareous nannofossils were identified from the contact between Kometan and Shiranish formations that is exposed in Chaqchaq valley, northwest of Sulaimaniyah city, NE Iraq. The recorded calcareous nannofossils' assemblages permit recognition of two biozones:
1- Aspidolithus parcus – Calculites ovalis Interval Biozone (CC 18 – CC 19)
2- Ceratolithoides aculeus Interval Biozone (CC 20)
Based on nannofossils biozonation, the contact between Kometan and Shiranish formations is considered to be conformable. In the studied area, it was found that the age of the Shiranish Formation extends to Early Campanian.

The geological and hydrogeological features, which are responsible for the relatively unusual existence of a hydrogen sulphide rich lake in the broad Ranya Plain is the main endeavor of this study. The lake is located 131 Km northwest of Sulaimaniyah city on the northwestern periphery of Dokan reservoir. To investigate the basin configuration and the subsurface setting of the lake and its surrounding area, two GPR profiles were laidout using a band width (Centre Frequency) 100-MHz unshielded antenna. For penetrating more depths; as well as mapping structural and stratigraphic situations of the subsurface that couldn't be achieved by GPR survey, one dimensional resistivity sounding was carried out.

Hydrochemical analysis of the water samples collected from the major lake and the surrounding smaller ones revealed that the water is of CaSO4 type, with domination of Ca and SO4 over Na and Cl. Values of δ18O and δ2H in water samples of Ganau lake, when plotted along the global meteoric water line shows that the two collected water samples from both the major and minor lakes have similar isotopic composition indicating that both of them are receiving water from the same flow zones, with diffuse recharge type. The tritium value indicates that the spring water is modern.

From combining together the acquired field results (geological, hydrogeological, and geophysical investigations); the occurrence of the lake and draining of the sulphuric spring in such a condition is attributed to a probable graben like faults on the crest of Ranya anticline, which facilitate both discharging of the deep artesian water from the underlying bituminous Jurassic rocks; or even from the deeper Triassic rocks. The continuous dissolution and the accompanying collapsing have contributed in formation of this lake and the sinkhole spring.

A detailed magnetic survey has been carried out in Taq-Kisra Archaeological Site, situated in Al-Mada'in city; about 32 Km southeast of Baghdad. The aim of this survey is to delineate the locations and extensions of the buried archaeological structures. The area was covered by (2 × 2) m net of magnetic measurements, with 5262 stations measured with an accuracy of up to ±1.8 nT. Residual magnetic intensity map of the site has been constructed after applying the necessary corrections on the raw data. Generally, the map shows linear magnetic anomalies that have archaeological meaning. The range of the achieved magnetic anomalies is (15 – 24) nT. Location of ten trenches, depending on the magnetic map, have been suggested for checking the obtained magnetic anomalies. The results of the excavations showed good relations between the observed magnetic anomalies and the causative sources, represented by archaeological features. The archaeological features that appeared through excavations are: the main mure, walls, floor, base of column and other archaeological remains. These have depths ranging between (0.25 – 2) m and they were built with clayey burned bricks, which have red and yellow colors. A map showing the suggested tracks and areas for future excavations in the site is prepared, too.

Red kaolinitic claystone from Al-Amij and Al-Hussainiyat regions in the Western Desert of Iraq were evaluated for the production of artificial pozzolana as cement admixtures. Both claystones were calcined in the temperature range of (500 – 900)º C at 100º C interval, for 45 and 60 min duration. The chemical and mineralogical properties of both raw materials and calcined samples were studied; they display useful information that helps to predict the preparation of pozzolana from the claystone. The influence of the calcination temperature and time on pozzolanic activity index were found (as in ASTM C311) and discussed. The results obtained showed that the burning temperature and the duration of burning have significant effect on the activity of the produced pozzolana (calcined claystone). It was also found that the activity index of the pozzolana produced from Al-Amij claystone was higher than that produced from Al-Hussainiyat claystone.

An exploration survey has been carried out in Albu-Gharis Saltern, western Iraq to follow- up previously mentioned relatively high K concentrations in the salt and in the brine. The present work is based on field observations, sampling, mineralogical and chemical analyses of salt crust, brine and sediments.

The results showed that all salt samples analyzed by X-ray diffraction contained sylvite (KCl) with halite as the dominant constituent. The older (dust-contaminated) salt crust contained 1.63% KCl and the recent (freshly precipitated) crust contained 3.52% KCl, whereas the brine contained 1.3% KCl with 330 gm/l salinity. The major salt constituent is NaCl, making about 83% of total salts in the crust and about 30% in the brine.

Compared to average K content in seawater (0.39 gm/l) and in the Arabian Gulf water (0.5 gm/l), the Albu-Gharis Saltern may be considered a potential potash resource in Iraq. KCl may be produced from the bitter solution left after NaCl precipitation from the brine. The Albu-Gharis brine is lower (one third) in potash concentration, but comparable in salinity to the Dead Sea, which contains 4.4% KCl and 315 gm/l salinity. However, the Dead Sea is highly different in other chemical constituents.

The studied area, Darbandi Khan – Sartaq Bammu, is located in the northeastern part of Iraq, along the Iraqi – Iranian international borders, about 50 Km southeast of Sulaimaniyah city (Fig.1), forming the southwestern limb of Bammu anticline. The studied area is characterized by well development of calcrete. The calcrete, as other Quaternary sediments is not well studied and presented in geological maps all over the Iraqi territory, though they cover considerable areas with different thicknesses.

The study of sources and origin of the hydro-chemical constituents in the Euphrates River and Haditha Lake from Al-Qaim to Al-Baghdadi, west Iraq was performed by regime observation in six stations during the water surplus and deficit periods of 2007 water year. The hydro-chemical properties of the Euphrates River and Haditha lake waters are determined, using the analysis results of 26 physico – chemical variables including major, minor and trace elements, acidity, hardness and electrical conductivity. The interpretation of the hydro – chemical phenomena are achieved according to statistical results of Regression Stat. Program (Curve Expert v1.3), calculating the correlation coefficients among the physico – chemical components of the water.

The hypothetical statistic (significant level) and significant difference results were used to determine the variations in water components along the Euphrates river valley. The study also determined the natural hydro – geochemical effectiveness within the Eco-system of Euphrates River and Haditha lake, to prove and reaches the other related environmental effectiveness, which affect the hydrologic system; such as ground water, waste water and irrigation drained water.

The environmental effectiveness are considered as a probable source for pollution in case of hydrologic system deterioration, which is increased by man activities through inadequate controlled process in river discharge across the gates of dams or caused by Draught Crises results from low rainfall and high evaporation. The study indicated a source case of Nitrogen species, such as nitrite and ammonium ions, resulted by the process of putrefaction, which affects the environment of water plants in the river and lake to the reduction case, causing the increasing of organic sludge in the bed load sediments, which became a good environment for living of micro organisms; then causing the life of human in danger, when using the water directly without treatment. The hydro – geochemistry of trace elements is examined to approach the probable pollution throughout the additional concentration percent along the river between the monitoring points, from Al-Qaim through Al-Baghdadi.

This study deals with the hydrochemical evaluation of the groundwater in Sha'abani –Bawara area, which is located in the middle and southern parts of Al-Jazira Area, central west Iraq. The study regarded that the Quaternary sediments are the main water bearing horizons in the study area, and may be connected with Fatha Formation (Middle Miocene), which consists of cyclic sediments; each cycle consists of green marl, limestone and gypsum. The cycles are repeated, with irregular thicknesses for each cycle and even each rock constituent. The main characteristic of the formation is the karstification, which had increased the porosity and permeability of the formation.

The Injana Formation consists of cyclic deposits; each cycle consists of reddish brown sandstone, siltstone and claystone. Very rarely thin (5 – 25 cm) horizons of limestone and gypsum may occur in the lowermost part of the formation. In some locations, Injana Formation (Upper Miocene) contains water, and is considered as the first aquifer below the Quaternary aquifer. The results of the chemical analysis are graphically represented in several classifications (Hem, Sulin classification, and Scholler – Sulin diagram). Further more, mathematical evaluation (cluster analysis) of the results were achieved to identify the origin of the ground water and mineral resources, and to support the more soluble salts in the groundwater, which include Sodium Chloride (NaCl), Magnesium Nitrate ]Mg(NO3)[, Calcium Bicarbonate ]Ca(HCO3)2[, and Calcium Sulphate (CaSO4).

In conclusion, the ground water in Sha'abani – Bawara area is saline, not good quality water and not suitable for human consumption. Nitrate concentration (52 – 827 mg/l) is slightly high in several wells. The relatively high proportion of nitrate is most probably due to the impact of fertilizers used by human activities. The water type is proved to be mainly of Sulphate and Chloride types.

Chemical, mineralogical and physical evaluation of clay deposits in south and north Amarah city, southern part of Iraq shows that the deposits have a high percentage of silt and medium to high plasticity. The chemical and mineralogical analysis revealed that SiO2 and Al2O3 are the main chemical components of the deposits, which indicate the high content of Quartz; from one hand and clay minerals, Montmorillonite, Chlorite and Kaolinite; on the other hand. The high percentage of CaCO3 shows the presence of predominant Calcite, in addition to slight increase in the average of sulfate, especially in north Amarah samples, which is highly related to the increase in the average of T.D.S. One hundred and eighty cylindrical samples were prepared from six mixtures of clay deposits and some different additives. The samples were formed by semi-dry method under 200 Kg/ cm2 as forming pressure, then the samples were dried and fired according to firing program under (800, 900 and 1000)° C, respectively.

The physical tests show that there is an improvement in the firing shrinkage, water absorption, compressive strength and efflorescence, especially by adding 10% and 15% of fine sand under (900 and 1000)° C. The produced bricks are within the requirements of Class A and B of ISO, 25, 1988, as compared to the properties of the produced bricks by brick plants of Amarah city, which are out of the ISO, 25, 1988 limits.

Light weight bricks were produced under some conditions by adding 10% and 15% of fine bacase to clay deposits, the prepared bricks have a good porosity, water absorption, light bulk density and good compressive strength and within the limits of international standards of light weight bricks.