Mineralogy and geochemistry of kaolinitic clays in the Şile Neogene Basin (İstanbul, Türkiye)

Authors

Bala EKİNCİ ŞANS Asst. Prof., İstanbulFollow
Oral SARIKAYA MSc, İstanbul Technical University, Department of Geological Engineering, Maslak, 34469, İstanbul, TürkiyeFollow
Fahri ESENLİ Prof. Dr., İstanbul Technical University, Department of Geological Engineering, Maslak, 34469, İstanbul, TürkiyeFollow
Şenel ÖZDAMAR Prof.Dr., İstanbul Technical University, Department of Geological Engineering, Maslak, 34469, İstanbul, TürkiyeFollow
Hakan TUNÇDEMİR Assoc.Prof.Dr., stanbul Technical University, Department of Mining Engineering, Maslak, 34469, İstanbul, TürkiyeFollow
Ümit KARADOĞAN Asst.Prof.Dr., İstanbul Technical University, Department of Civil Engineering, Maslak, 34469, İstanbul, TürkiyeFollow
Mustafa KUMRAL Prof.Dr., İstanbul Technical University, Department of Geological Engineering, Maslak, 34469, İstanbul, TürkiyeFollow

DOI

10.19111/bulletinofmre.1627560

Abstract

Şile Neogene Basin (ŞNB) is one of the world’s crucial sedimentary clay-sand-coal basins, where approximately 3 million tons of clay and 20 million tons of sand are produced annually. The ŞNB, with a thickness of <54 >m, lies unconformably on partly Paleozoic and partly Mesozoic basement units. Clay levels with a total thickness ofkaolinite, quartz and illite, and small amounts of Ca-smectite, mixed-layered phase (I/S), feldspar, siderite, chlorite, muscovite (+/- sericite), anatase, iron oxides/hydroxides, alunite and pyrite. Geochemically, most of the major oxides and SiO2/Al2O3 ratios do not show significant changes on the vertical or lateral scale. On the other hand, trace elements, REE contents and Th/U ratios of the clay levels overlaying the Paleozoic sandstones are higher than the clays overlaying the Mesozoic volcanics. REEs are higher in the lower part of the Neogene sequence than in the upper part. The mineralogical and geochemical data show that the existing material of ŞNB is an accumulation of different basement rock groups, the mineral type and size of the transported fragments varied at short intervals and carried the effects of various environmental conditions and alteration types.

Recommended Citation

EKİNCİ ŞANS, Bala Asst. Prof.; SARIKAYA, Oral MSc; ESENLİ, Fahri Prof. Dr.; ÖZDAMAR, Şenel Prof.Dr.; TUNÇDEMİR, Hakan Assoc.Prof.Dr.; KARADOĞAN, Ümit Asst.Prof.Dr.; and KUMRAL, Mustafa Prof.Dr. (2025) "Mineralogy and geochemistry of kaolinitic clays in the Şile Neogene Basin (İstanbul, Türkiye)," Bulletin of the Mineral Research and Exploration: Vol. 2025: Iss. 178, Article 2.
DOI: https://doi.org/10.19111/bulletinofmre.1627560