Mineralogical and geochemical properties of non-marine sedimentary units in Temelli Basin (Polatlı-Ankara)
Abstract
Study area located in south-west of Ankara in Central Anatolia, is a fault-controlled graben basin. Neogene aged clastic, clayey, dolomitic, tuffitic and evaporitic rocks form dominant lithology in the region. Four deep drillings were made in the field. The basin consists of a quite thick sequence of fluvial and lacustrine units. Fluvial sediments made up of detrital units such as poorly consolidated conglomerate, sandstone, mudstone, siltstone and claystone. Lacustrine sediments commonly made up of fine-grained clastics (mudstone, claystone), carbonates (clayey limestone, marl) and evaporites (sulfates and chlorides). The composition of some levels is almost pure, consisting of one or two evaporite minerals such as halite and anhydrite, while in some levels clay minerals, zeolite and other silicate minerals are present together. Evaporite and non-evaporite units show facies development in vertical and lateral directions. Subhedral lenticular, bar shaped glauberite, cubic halite, rhomboedric dolomite, prismatic celestine, anhydrite and gypsum crystals were observed in SEM studies. Ca, Na, S ions dominate the major element in the evaporate samples. The positive correlation of SiO2 with K2O, Al2O3, Fe2O3 and TiO2 indicates the presence of smectite, illite, and feldspar. The high differences (528.8-10061.4ppm) in strontium contents between carbonate and sulfate levels reflect hydrologically unstable conditions and sedimentation in shallow waters. LRE element enrichment relative to HRE elements and Eu anomaly indicated that the basin is upper continental crust origin and fed from a volcanic source.
Keywords
References
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Details
Primary Language
English
Subjects
Applied Geology
Journal Section
Research Article
Authors
Tülay Altay
*
Türkiye
Early Pub Date
November 2, 2025
Publication Date
March 16, 2026
Submission Date
February 28, 2025
Acceptance Date
August 21, 2025
Published in Issue
Year 2026 Volume: 32 Number: 2