Mautaz Al-Dabbas, Salih Muhammad Awadh & Ayad Abed Zaid
الملخص الانجليزي
This study deals with the mineralogical and
geochemistry of the Euphrates Formation (Lower Miocene)
in Bahr Al-Najaf area in order to assess the lithofacies of the
Euphrates Formation for Portland cement manufacturing.
Petrographic and mineralogical studies were carried out on
210 core samples, collected from 21 boreholes, and showed
that calcite is the dominant mineral with few amounts of
quartz, gypsum, feldspar, and a rare amount of dolomite.
Clay mineral suites (palygorskite, kaolinite, montmorillonite,
and illite) formed about 5% from the total mineral
composition. Palygorskite precipitated directly in alkali
shallow water rich with Si and Mg ions. Chemical
weathering of feldspar under acidic conditions participated
in formation of Kaolinite. Geochemistry showed that there is
no high variation in chemical constituents with depth, and
the average of CaO (51.5), MgO (0.83), SO3 (0.54), SiO2
(4.3), Fe2O3 (0.45), Al2O3 (0.93), L.O.I (40.7), Na2O3
(0.08), K2O (0.14), and Cl- (0.1) qualified the lithofacies of
Euphrates Formation to be raw materials suitable for
manufacturing the Portland cement. Triangle Block method
is applied to estimate the reserve on square area (2×2 km2)
which is computed to be 63 million tons of medium-tough
limestone as potential probable reserve.