Mineralogical Evaluation of Some Soils Representing The Geomorphic Units in The Northwestern Coast of Egypt

FIFTEEN soil samples from successive strata were collected for five soil profiles representing assimilated four geomorphology units in the northwestern coast of Egypt. For mineralogical structure, the soil samples were studied microscopically and X-ray diffraction was done. The polarized microscopic examination of the sand fraction between 0.125 and 0.063 mm showed that. Light minerals were dominated by quartz then by feldspar minerals. The presence of feldspars indicates that the soils are young from the pedological view point. Heavy minerals were the dominion of the total opaque minerals. The predominant minerals in nonopaque minerals were: Pyroxene minerals, Parametamorphic minerals. High-resistance mineral for weathering was predominant with zircon mineral. Distributions of the resistant minerals indicate that the soils are generally of multi-origin and/or multi-depositional regime and are thus young. X-ray diffraction of clay minerals showed the predominance of kaolinite, followed by montmorillonite, then mica trioctahedral, halloysite, -vermiculite, palygroskite, -regularly interstratified minerals -(vermiculite + mica), talc mineral and regularly interstratified minerals (montmorillonite + mica or chlorite + vermiculite), regularly interstratified minerals (chlorite + montmorillonite or saponite) chlorite, mica dioctahedral. The accessory minerals were dominated by quartz mineral. The study showed that the variable content of clay minerals in the geomorphic units in the study soil is essentially inherited from the parent materials, with some modification during the spatial deposition system and a slight change if there is any effect of the weathering factors on the studied soils.