Twenty sand samples were collected from the sand dunes of Missan fields, Southeastern Iraq. Grain size distribution, mineralogical and chemical composition were studied for the total, medium, and fine-size sand fractions. The grain size analysis shows that the sand is the main component, followed by silt and trace of clay. The predominant grain size of sand is 0.250 to 0.500 mm, which forms more than 57.28 %, which indicates that these dunes were formed under the influence of relatively strong winds and the sedimentary material is close to the source. The light components are quartz, feldspar, and different rock fragments, while the heavy mineral assemblages are composed of opaque minerals, chlorite, mica, and amphiboles. Pyroxene and epidote are the common minerals, while zircon, garnet, tourmaline, rutile, kyanite, and staurolite are in minor amounts. X-ray diffraction (XRD) data reveals that the predominant non-clay minerals are quartz, calcite, feldspar, and gypsum. While the dominant clay minerals are palygorskite and illite, followed by kaolinite and the mixed layer of montmorillonite – chlorite. There is a negative relationship between the percentage of heavy minerals and the grain size of sand. Dunes are distinguished by a relatively high percentage of minerals derived from intermediate and basic igneous rocks located in the Zagros belt, northern Iraq. They also may be derived from local source formations, Injana and Mukdadiya in the surrounding areas. The average geochemical components of sand as indicated by X-ray fluorescence (XRF) are; SiO2 (61.36%), which is mainly represented by quartz, CaO (14.08%) related to the presence of carbonate, SO3 (0.05%) is represented by gypsum, Al2O3 (6.76 %) and alkalis (2.30%) reflect the presence of the K-feldspar and clay minerals, Fe2O3 (3.2%) is attributed to the presence of hematite, magnetite and limonite minerals. SiO2 is concentrated in a medium sand size fraction, while the other oxides are concentrated in a fine sand size fraction.
The purpose of the present paper is to define the minerals content in the Najaf Dunes fields and the origin of these sand sediments in the southwestern parts of Iraq. There are three types of dunes in this field were described, the barchan, longitudinal, and dome dunes and additional types e.g. Nabkha, Barchanoid ridges, and sand sheet dunes. The study area was divided into three areas according to the geographical position, and numerous samples were collected from this field.
The mineralogical study consists from three methods these are; the first: separation of sand samples into the light and heavy minerals by heavy liquids,where performed on 30 samples. The second method; carbonate content performed on 60 samples, and the thir
... Show MoreThis research concerns with the study of the sand dunes sedimentary structures in two areas from dunes field of Najaf governorate these are; 1)Al-Rahimiya and 2)Ain Mazlun areas, where the first area consists from barchans, barchanoid, and nabkha dunes types, while the second area has the dome, longitudinal, nabkha, and sand sheet dunes types.
The affected prevailing wind direction is obvious on the study area, where has the NW-SE bearing and the sedimentary structures were influenced by prevailing and local wind directions in studied areas.
Many types of sedimentary structures recognized in the studied areas these are; cross stratification, ripple marks, slump (grain flow), adhesion structures, and bioturbation structure
... Show MoreThe main aim of this research is to define the mineralogical composition of recent sediments deposited around the Al-Teeb river basin in eastern Missan, trying to determine the provenance or the source of these sediments.
The study area represents the southeastern edge of the Mesopotamian Plain and is part of it. Quaternary deposits cover most of the area. It is clayey with old sea and river deposits and part of aeolian deposits.
These sediments cover 95% of the study area, while the older rocks, which date back to the Tertiary (Late Miocene – Pliocene), exposed in the area east and northeast of the Al-Teeb area, made up hills which back to the undifferentiated Pliocene Mukdadiya and Bai-Hassan f
... Show MoreFifteen samples were collected from recent sediments grouping at 80 km east Samawa City, southern Iraq. Three selected samples for grain size analysis and twelve samples for chemical and biofacies analysis. Grain size analysis indicated that the sediment is mainly composed of the silt and clay with a small amount of sand. Most of the samples considered to be as clayey silt. The dominated non clay minerals are Quartz, Calcite, and Dolomite, while the clay minerals are composed of mixed Montmorillonite- Chlorite, Palygorskite, Illite and Kaolinite. Chemical analysis showed that all samples have high concentrations of SiO2 and CaO in comparison with Al2O3, MgO, Fe2O3, K2O and N2O. The identified fauna
... Show MoreGypsiferous soil deposits (Gypcrete) are weakly consolidate earthy mixture of secondary gypsum, sand and clay. It is formed in arid and semi- arid area with annual precipitation rainfall less than 400mm. These sediments occur in surface and subsurface in region of little rainfall and rapid evaporation. This research deals with the study of gypcrete in Alexandria to improve the mineralogical and geochemical properties of the gypcrete. The gypcrete soil is used as raw material to produce the plaster for building purposes. Three samples of gypcrete were chemically and geochemically analyzed. The common mineral is howed in 0-0.5m Gypsum followed by Calcite in 0-1m and Quartz in 1-1.5m due to leaching and infiltration by rainfall as well as it
... Show MoreThis paper presents the finite strain results from seven oriented samples data on Tertiary sandstone of Muqdadiya Formation and (400) samples of pebbles and conglomerate of Bai –Hassan Formation at the southwestern limb of Al-Tib Anticline in the Southeastern part of Iraq. Measurement and analysis of finite strain are carried out including these rocks at fluvio- lacustrine environment. The present study followed Fry method. The computed strain was, in the form of ellipses, within three prepared perpendicular planes in a single sample and Center to Center method was used to determine the strain ratio of the these samples. The strain in the studied area is low, this is mainly due to the sampled rocks underwent brittle deformation d
... Show MoreDuring the past forty years, and due to the global climate changes, Iraq had and still suffering from the spreading and expansion of large dune fields in which many new generations have been accumulated, and older ones have expanded leading to the desertification of huge agricultural and urban areas and causing vast environmental problems that have a drastic effect on the life style of the population. To tackle such a problem, many methods have been suggested and even more are applied to fix the dunes or at least to limit their spreading so that to lessen the environmental impact. Such efforts were tried in many dune areas in Iraq, but it was in vain due to the classical nature of remedy that deals only with temporary and limited results
... Show MoreFifty five surface and subsurface soil samples were taken from the area between Tigris and Euphrates Rivers along the Main Drain course from north Baghdad to Basrah to evaluate the geochemical, physical characteristics and the probability contamination of these samples. The study area is covered by Quaternary sediments of complex alternation of sand, silt and clay. Significant variation in the textural content of the present soils is observed, where the northern and southern parts are characterized by silt predominance, while sand is prevailing in the central parts as a result of the extensive spreading of aeolian deposits represented mostly by sand dunes. Mineralogical analysis explains wide variations in the heavy minerals distribution
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