Iraqi Bulletin of Geology and Mining

A reconnaissance sampling of air-borne dust in Baghdad city has been carried out in 14 sampling stations in addition to streets dust in 12 stations. The analysis of these samples showed that Pb concentration in the former ranged between (14 – 95) ppm (mean 49 ppm) and in the latter between (24 – 280) ppm (mean 92 ppm) compared to about 7 ppm average Pb concentration of more than 20 000 samples of unpolluted soil samples collected from the dust source areas (Western and Southern Deserts of Iraq). These anomalously high concentrations of Pb in the air-borne dust are extremely hazardous for human health, being directly introduced to the respiratory system by unavoidable inhalation causing health defects and fatal diseases. The source of air-borne Pb-rich dust is obviously local and can be directly related to Pb pollutants in the city, especially Pb-additives to the gasoline, still used in Iraq, and to the illegal primitive Pb smelters.

This research is concerned with the study of the microfacies analysis of Sinjar Formation from Baranan Mountain, southwest of Sulaimaniyah city, NE Iraq. The topic of the research represents the first approach in the area for identification carbonate microfacies and microfossils. Thus, the study is applied to an area extremely rich in Paleocene – Eocene paleoflora and paleofauna, mainly represented by red and green algae, corals, and especially large benthic foraminifera (rotallids, discocyclinids and soritids). Two sections were measured in the field, Hazar Merd Section, 135 m thick and Qazan Section, 75 m thick; within the two sections 368 samples were collected. The studying of the thin sections (about 400) allowed us to present some results on the facies succession, micropaleontological content, age and reconstruction of the paleoenvironment of Sinjar Formation.

Gulneri Formation (Early Turonian) consists, mainly as previously described, of shale deposited in euxinic and small relic basin. In the present study, it was found that it consists mainly of marl and marly limestone with no more than 20% of laminated shale. Thin section study showed that the shale is highly deformed, with foliation-like texture. Therefore, most probably the previously described shale is originally marl, which is changed to laminated shale-like rock, by pressure that released insoluble residue and bitumen materials from surrounding rocks. By filtering of these materials, the marl was changed to black shale-like rock. The effect of the pressure is observed by bending of the shale laminae around the spherical limestone bodies and the flattening of planktonic foraminifera to elongated shape.
The upper and lower contacts of the Gulneri Formation seem to be conformable; as conglomerates, erosional surfaces and paleosols were not found. But, short duration of possible submarine erosion or slow rate of deposition is not excluded. There are spherical limestone bodies in the formation and near the contacts, but they are not conglomerate; as assumed previously. Field and thin section studies reveled that the bodies are ball and pillow-like structures, which are formed by pressure; this is evidenced by the absence of silt and sand size grains in the ball and pillow-like structures. This formation occurs only in Dokan dam site (Northwest of Sulaimaniyah) and it does not exist in near by surrounding areas, therefore, we suggest its combination with Kometan Formation.

Late Oligocene – Early Miocene rocks are not previously known in the High Folded Zone, especially in northeast Iraq; neither in outcrops nor in subsurface sections. In most areas, the exposures of the Pila Spi Formation (Middle – Late Eocene) are overlain usually by the exposures of the Fat\'ha Formation (Middle Miocene).
Recent field observations and lithostratigraphic study, of an area near Basara Gorge, south of Sulaimaniyah, Northeast Iraq, revealed the presence of a succession (20 – 25 m thick) between the Pila Spi and Fat\'ha formations. This succession has unconformable contact with the underlying Pila Spi Formation, marked by the presence of (6 – 8) m thick, sedimentary breccias and conglomerate indicating the presence of rocks of different ages. The succession consists of two main parts; the lower part consists of breccia, conglomerate, and red sandstone and claystone, whereas the upper part consists of fossiliferous limestone interbedded with green marl.
Micropaleontological studies, of samples collected from the studied succession, proved the presence of Late Oligocene – Early Miocene rocks between the Pila Spi Formation (Middle – Late Eocene) and Fat\'ha Formation (Middle Miocene), with indication of mixing environments (basinal/ shelf). The lithological diversity indicates the presence of a break in sedimentation, indicated by breccia and conglomerate over the Pila Spi Formation. Moreover, the cyclic repetition of green marl with limestone indicates oscillation of the sea level during deposition of the studied succession.
This is the first time to recognize rocks with such age and mixed environments from the areas of the High Folded Zone in Sulaimaniyah Governorate, Northeast Iraq.

The contact between the uplifted and subsided areas that represents the Neotectonic movements, which are presented by mean of contours, in West of Iraq, are revised and reconstructed. The contours, previously, were constructed depending on the contact between Fat'ha and Injana formations, which represents the last sea level during the Middle Miocene. The contours, in West of Iraq, are reconstructed depending on the top of the Nfayil Formation that is the equivalent of the Fat'ha Formation.
Previously, the contours, in the extreme western parts of Iraq, where the Injana Formation is not exposed, were constructed depending on the bottom of the Zahra Formation. In this study, these contours are canceled, because the Zahra Formation is proved to be of Pliocene – Pleistocene age, therefore it is younger than the considered contact. The re-constructed contours, which are hypothetical, have different values, shapes and extensions, as compared to the previously constructed contours. The calculated rate of uplifting has changed too, depending on the values of the re-constructed contours.
Many features indicating Neotectonic movements were recognized. Majority of them are related to active faults, dislocated drainage system and their control. These are indicated mainly using remote sensing techniques.

The concealed geology and structures of southern part of Iraq has been investigated by analyzing the gravity fields. The main structural and tectonic trends are clearly defined in the N – S and NW – SE directions through using Fan Filtering technique. Deep regional geological trends represent basement features, while shallow structural trends are confined to structures in the sedimentary rocks.
The deep trends act as zones of weakness that affected the sedimentary cover through the different phases of the Alpine Orogeny and led to create different types of N – S and NW – SE folded shallow structures. The obtained structural trends indicate the possibility of N – S and NW – SE distribution, of the geological features all over the central and southern part of Iraq and they add new information concerning deep geologic structures.

The Sarchinar spring is one of the largest springs in northern Iraq, it supplies municipal water for the Sulaimaniyah city of 700000 inhabitants. The outlet drains a large catchment area, some 200 Km2 of the Sarchinar – Chaq Chaq karstic system.
The recharge of the spring is based on: A) the diffuse infiltration of rainfall through the exposed outcrops of Jurassic and Cretaceous (Qamchuqa – Kometan or Balambo formations, thickly-bedded and highly fractured limestone layers); B) the percolation of runoff and intermittent stream water of Chaq Chaq valley through tectonically active zones. During the recession periods of the extremely dry 1999 and 2000, the minimal discharge of the system was around 600 l/sec. The recorded maximum discharge during the period 1999 – 2005 was 7454 l/sec (March, 2003).
For the characterization of karstic aquifer and discharge regime evaluation, the analyses of input – output relationship was applied including the autocorrelation, cross-correlation and spectral density methods. The main characteristics are cyclic variations and significant aquifer storage capacity. During winter time, the system reacts to rainfall events with a delay of a few days representing the minimum travel time for the recharging inputs. Meanwhile, a slow reaction could be observed during low water period after approximately one month (rainfall at the beginning of May transferred as output at the beginning of June).
The regime of this spring is determined by several factors, the principals are: arid climate and unstable recharge (six months without rainfall), well karstified and fractured aquifer system, and recharge by seepage from the nearby Chaq Chaq valley.

Shear serpentinite represents two meters thick serpentinite, formed at the contact of the Penjween Ophiolite sequence and Tertiary molasses (Miocene Merga Red Beds). It is formed of metamorphism of massive serpentinite as a result of Tertiary post-collision tectonics. Mineralogically, shear serpentinite consists of serpentine polymorphs mainly antigorite, lizardite – chrysotile serpentines, bands of carbonate minerals, subordinate amount of magnetite. There are two types of the later: a) chemically zoned large grains with cores of primary Cr-spinel and/ or pre-serpentanization ferrichromites; and b) small, unzoned, pure syn-serpentanization magnetite grains. The first type of magnetite occupies the outermost of rimmed Cr-spinel. Lizardite – chrysotile fibers enclose strips within antigorite suggesting that it formed on expense of this mixture of chrysotile and lizardite. Antigorite is formed under shear stress condition during post-collision tectonics. Chemical analysis of serpentine polymorphs shows that the antigorite is richer in FeO and poorer in MgO and SiO2 than that in lizardite – chrysotile serpentines. The co-existing of high-Fe antigorite with lizardite – chrysotile assemblage may suggest that the earlier is stable in slightly higher temperature condition (>300° C) than that of lizardite and chrysotile serpentine. Back scattered images (BSE) show that antigorite is granular light gray, whereas the lizardite – chrysotile is fibrous dark gray. Chlorite is a Cr-rich clniochlorite (2.6 wt.% Cr2O3). It is formed through the reaction of ferrichromite with serpentine minerals during retrograde metamorphism. The occurrence of this shear serpentine along post-collision strike – slip fault zones suggests that they used these zones of weakness for protrusion.

This study deals with the lithological units of Aqra Formation (Late Cretaceous), which interfingers with Tanjero Formation at the northeastern limb of Azmar Anticline, Chwarta area, Sulaimaniyah Governorate, NE Iraq. Ninty one samples were collected from two sections, the first is in Zarda Bee village and the second from Mawkaba area. The study revealed four microfacies depending on the fossils content and lithological characters, these are:
1- Pelagic Lime Wackestone Facies
2- Foraminiferal Lime Wackestone Facies
3- Larger Foraminiferal Lime Wackestone Facies
4- Larger Foraminiferal Lime Packstone Facies
Depending on the high diversity in the species of different groups of foraminiferal assemblage, the depositional environment of Aqra Formation was suggested by application of the environment triangle, which shows that the depositional environment extends from near pelagic area to the toe of slope area and its continuation to the shallow water area, and the rudist reef body, although the counting of the fossils content of the foraminiferal species shows that the Aqra Formation (in Zarda Bee section) was deposited in deeper environment.

Many hydro-geochemical survey projects were carried out during 1975 – 1989 in the Iraqi Southern and Western Deserts for preliminary evaluation of a hidden radioactive ore bodies. The ground water in these areas plays very important role in human living and land developments, the depth of the ground water varies from artesian or near ground surface; along the bank of Euphrates river to 300 m. The regional trend the ground water movement is towards the east and north east.
Seventy water samples were collected from water wells and springs, their concentrations range from (5 – 261) µg/l Uranium. Arithmetic average Uranium concentration for all samples was 51.2 µg/l. Seventy percent of the water samples of the ground water and springs, in these areas exceed the USEPA proposed maximum contaminant level (MCL) for Uranium, being 20 µg/l. The Uranium concentration in shallow ground water (hand dug wells) is higher than it's concentration in deep water well, because the shallow water is in contact with or near from the radioactive resource materials, besides, the shallow waters is not rejuvenated and mixed with other deep water aquifers.
A health risk exists for persons consuming water that contain Uranium exceeding 20 µg/l, due to it's chemical toxicity. Also there are harsh effects on the renal system for users of these tainted water. Appropriate water treatment is recommended for water supplies exceeding 100 µg/l Uranium.

Many areas in Iraq suffer from desertification, expressed as gypsiferous soils and sand dunes. One of the most affected areas is the Tigris basin extending from Baghdad to Beygee, which is considered an important rural and agricultural area in Iraq. This paper deals with a laboratory study to investigate the influence of adding bentonite on increasing the fertility of the gypsiferous and sandy soils as far as increasing their capacity to accommodate exchangeable potassium added to the soil as NPK fertilizer.
Two samples were investigated; the first is sandy soil from Beygee area and the second is gypsiferous soil from Tikrit area. The samples were investigated and analysed for grain-size, mineralogy, chemical composition and salt composition, as well as the determination of soluble, exchangeable (ex) and fixed K in these samples.