Origin of iron-opal-chalcedony deposits near Sivrihisar, Turkey
4th Biennial SGA Meeting on Mineral Deposits - Research and Exploration: Where do They Meet, Turku, Finland, 11 - 13 August 1997, pp.729-732, (Full Text)
- Publication Type: Conference Paper / Full Text
- Volume:
- City: Turku
- Country: Finland
- Page Numbers: pp.729-732
- Dokuz Eylül University Affiliated: No
Abstract
The iron and opal-chalcedony deposits in mafic-ultramafic rocks scattered around Sivrihisar have been classified into two types. The first type, the lateritic deposits, formed under favourable morpho-climatic conditions in the Middle Miocene concordantly within the weathering profile of a series of peridotites and serpentinites of Paleozioc-Triassic age. These deposits are massive iron-opal-chalcedony deposits with a concentration of nickeliferous minerals in the saprolite zones. The second type, the vein type opal-chalcedony deposits, formed locally by hydrothermal replacement, the mineralising fluids originating from the lateritic deposits and moving via fractures which developed during the extensional tectonic regime of Northwestern Anatolia in the Late Tortonian.