GEOLOGY AND ORIGIN OF SAME CORBONATE-HOSTED HOLLOYSITE DEPOSITS IN NW - ANATOLIA (TURKEY)

Abstract

Geology and origin of some halloysite deposits in the provinces Çanakkale and Balıkesir (NW-Anatolia-Turkey) are investigated in this study. The deposits of Taban, Ilicaoba, Karasu-Kabakla. Şahbaz and Turplu are mostly located on the contacts of altered Neogene volcanics and Jurassic limestons. Pyrite, manganese, gibbsite and some alunite are the accesorry mineralisations. Based on the geological position of the halloysites over the probably karstic topography of the limestones: the absence of halloysite in the volcanics and the correlation of the REE's with the carbonate rocks; the origin of the deposits are suggested to be originated by partial dissolution of the hostrock limestones and formation of halloysite directly from Al and Sirich acidis fluids.