Applied Chemical Engineering

Weathering indices and mineralogical composition of the sand fraction in soils from the western desert of holy Karbala governorate, Iraq

Shireen Mudhafar Ali Alkhalil

Department of Desertification Combat, College of Agricultural Engineering Sciences, University of Baghdad, Baghdad, 10071,Iraq

DOI: https://doi.org/10.59429/ace.v8i4.5760

Keywords: Light and heavy minerals; Mineral weathering Index MWI; ZTR indicators

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Abstract

This study focuses on analyzing the mineral composition of sand fraction was separated from clay and silt in selected soils of the Western Desert in Karbala Governorate, Iraq, and assessing the intensity of Mineral Weathering Index MWI and ZTR indicators. Sixteen samples were collected from depths of 0–30 cm, sand was separated from clay and silt, then light and heavy minerals were identified with polarized light microscope. The results showed that monocrystalline quartz dominated by 21.1-26.9%, while polycrystalline quartz ranged between 2.7–4.6%. Feldspar content ranged 2-3.9%, and carbonate rock fragments accounted for  28.2–40.2%. Heavy minerals were the most abundant which resented by  iron oxides at 39.5-47.7%. Chlorite is present with 7.8-10.1%, biotite mica 4.4-6.5%, and muscovite 4.9–6.9%. Unstable minerals such as pyroxene and amphiboles ranged from 3.4–6.8%. MWI values ranged from 0.33-0.44, and ZTR values between 21.1-26.9, moderate to low weathering and low to moderate mineral maturity. These results reflect the nature of sedimentary deposits and the impact of a dry desert environment on limited chemical weathering.

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References

[1]. E. Gül, S.Esen.High desertification susceptibility in forest ecosystems revealed by the Environmental Sensitivity Area Index (ESAI). Sustainability. 2024 16(23), 10409. https://doi.org/10.3390/su162310409

[2]. B. H., Abdulmahdi, F. M. Abdulhussein. Geochemistry of the kaolinite-rich claystone in Western Iraq. Iraqi Journal of Science,2025. 66(6), 2370–2381. https://doi.org/10.24996/ijs.2025.66.6.15

[3]. H. A. Al-Amar. Geotechnical and Geochemical Study of Shatt Al-Hilla Banks' Soil in Babylon Governorate, Middle of Iraq. Iraqi National Journal of Earth Sciences. 2025. 25(1), 222–231. https://doi.org/10.33899/earth.2024.144800.1177

[4]. S. N. S. Al Baghdady, L. A. S. Alabadi .Studying and diagnosing the heavy and light sand minerals for some of the soils in southern and northern Iraq. IOP Conference Series: Earth and Environmental Science,2021. 735(1), 012081. https://doi.org/10.1088/1755-1315/735/1/012081

[5]. S. A. Ali. Variations in heavy minerals as indicators of provenance of the recent sediments from the Lesser Zab River, north Iraq. Kirkuk University Journal-Scientific Studies.2006. 1(1), 37–50. https://doi.org/10.32894/kujss.2006.43637

[6]. M. L. Hussien, M. R. A. Al-Owaidi, A. J. Al-Khafaji, M. D. Abduulah Geochemical and heavy minerals investigation to identify provenance of dunes and valley sediments at Al-Muthanna, southern Iraq. Modeling Earth Systems and Environment.2022. 9(2), 129-143. https://doi.org/10.1007/s40808-022-01473-9

[7]. H. B. Milner, Sedimentary petrography. 4thed. 1962. Murby and Co. London.

[8]. P.F. Kerr, Optical mineralogy.4th ed. McGraw-Hill Book Co. 1977. Inc. New York, U.S.A.

[9]. S. Ramadan, M.A. Hamdan, M. Abdel Wahed. The provenance and history of Abu Muharak barchan sands (Kharga Depression) inferred from textural, mineralogical, and geochemical perspectives. Arabian Journal of Geosciences. 2022. 15(1582),13-28. https://doi.org/10.1007/s12517-022-10848-2

[10]. M. Bernet. K.N. Bassett, Quartz types of the eocene broken river formation, mount somers: discrimination of volcanic versus metamorphic source rocks. New Zealand. Journal of Geology and Geophysics.2016.59 (2), 274–285. https://doi.org/10.1080/00288306.2015.1132743

[11]. SH. M. A AlKhalil. A comparative study of organic and mineral acids in the release of potassium from potassium feldspar minerals. IOP Conf. Ser.: Earth Environ. Sci. 2025.1487 012200. https://doi:10.1088/1755-1315/1487/1/012200

[12]. SH. M. A AlKhalil, S. K. Essa. Effect of sedimentation source on the nature occurrence and distribution of the feldspar in some soil of alluvial plain Iraq. Plant Archives. 2020. 20(2), 812-822 https://www.plantarchives.org/SPL%20ISSUE%2020-2/119__812-822_.pdf

[13]. SH. M. A AlKhalil, S. K. Essa. Effect of sedimentary source on the properties of sphericity and roundness of feldspar minerals in some soils of the alluvial plain. Indian Journal of Ecology. 2021. 48(1), 315-318 https://indianecologicalsociety.com/wp content/themes/ecology/volume_pdfs/48(1)_removed%20(1)-53.pdf

[14]. V.K. Sissakian, H.K. Al-Jiburi, H.S. Al-Mimar. Geological Hazards in Karbala Quadrangle. Journal of African Earth Sciences.2014. 95, 89–104. https://doi.org/10.1016/j.jafrearsci.2013.09.007

[15]. Q. Zhang, B. Zhang, Q. Yu, et al,. Study on the Provenance and Tectonic Setting of Mudstone in the Lower Silurian Longmaxi Formation of the Yanyuan Basin on the Western Margin of the Yangtze Platform. Minerals.2023. 13(2), 194. https://doi.org/10.3390/min13020194

[16]. Y. B. Mohammad, S. M. Awadh Geochemistryof Sabkhas in Abu Ghraib, Western Baghdad, Iraq. Iraqi Geological Journal. 2023. 56 (2B).145-158. https://doi.org/10.46717/igj.56.2B.11ms-2023-8-20

[17]. A. R. Ali1, S. A. Jassim , Z. N. Aladeen. The Role of Heavy Minerals in Understanding the Provenance of Sandstone: An Example from the Upper Cretaceous Tanjero Formation, Surdash Region, Northeastern Iraq .Iraqi Geological Journal.2022. 55 (1E), 94-109 https://doi.org/10.46717/igj.55.1E.9Ms-2022-05-25

[18]. C. Li, P. Shen, Y. Zhao, P. Li, L. Zhang, H. Pan. Mineral chemistry of chlorite in different geologic environments and its implications for porphyry Cu ± Au ± Mo deposits. Ore Geology Reviews. 2022. 145, 105112. https://doi.org/10.1016/j.oregeorev.2022.105112.

[19]. M. Auer, R. Deguise, , S. White. Zircon and tourmaline as geochronological tools: applications in metamorphic and igneous rocks. Journal of Geology. 2018. 126(3), 305-320. https://doi.org/10.1086/693246.

[20]. B.O. Al-Jaff. Using center of gravity equation for mica and smectite in evaluation of K-status in some soils of Iraqi Kurdistan region Iraqi Journal of Agricultural Sciences.2024. 55(3): 1110-1119. https://doi.org/10.36103/w953r397.

[21]. R. Jassin, W. Goff. Mineralogy of amphibole-bearing rocks: Implications for tectonic settings. Journal of Mineral Science, 2006 . 52(1): 97-108. https://doi.org/10.1016/j.minsci.2006.02.004.

[22]. J.F. Hubert. A zircon-tourmaline-rutile maturity index and the interdependence of the composition of heavy mineral assemblages with the gross composition and texture of sandstones. journal of Sedimentary Research ,1962. 32 (3): 440–450 https://doi.org/10.1306/74d70ce5-2b21-11d7-8648000102c1865d