Akademik Veri Yönetim Sistemi
CARBONATES AND EVAPORITES, cilt.13, sa.2, ss.198-206, 1998 (SCI-Expanded, Scopus)
Neogene (Upper Miocene-Pliocene) lacustrine sediments of northern Konya consist of conglomerate, sandstone, marl, mudstone, claystone, clayey limestone, and limestone. Limestones are white, beige-cream colored, fine-grained and contain remnants of plant roots. Brecciation, calcretion, mud cracks, and dissolution voids are common. Claystones are typical with white and green colors. Green claystone cropping out at the lower part of the sequence is alternated with mudstone and sandstone. White claystone alternating with carbonate units appears at the upper part of the sequence. Carbonate units are found as intercalated layers and lenses of conglomerate, sandstone, and mudstone. Calcite, dolomite, feldspar, and quartz minerals are dominant in the study area. They are accompanied by sepiolite, palygorskite, smectite, chlorite, and illite minerals hosted by white colored clayey limestone and claystone. In addition, on the green colored claystones, minerals such as chlorite, smectite, and illite are formed. SEM studies indicate that sepiolite-palygorskite fiber and fiber bundles cover calcite and dolomite. Calcite and dolomite are of hexagonal and rhombic crystal types. These minerals show a meniscus type cement which characterizes a vadose zone. Paragenesis and textural features of the minerals determined in the study area indicate that precipitation should occur due to climate fluctuations ranging from arid, semi-arid, and wet conditions. Changes in climatic conditions does affect the lacustrine water chemistry and precipitation of carbonate and detrital units. Sepiolite and palygorskite form authigenically as a result of the calcretion of carbonate units in alkaline conditions, high Si and Mg activity, and low Al.