Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi

Yazarlar: Abdurrahman LERMİ, Mustafa SÖNMEZ, Faruk AYDIN

Konular:Mühendislik

DOI:10.28948/ngumuh.502300

Anahtar Kelimeler:Hydrothermal alteration,Alunite-jarosite,Mass transfer calculations,Tepeköy volcanites,Niğde

Özet: Andesite, basalt and their pyroclastic deposits are widespread around Tepeköy. The volcanic rocks are predominantly andesitic and rarely basaltic in composition. Alteration developed near around volcanic eruption center and along the fault zones. Quartz, sericite, chlorite, epidote and carbonate minerals are the dominant alteration minerals. Based on the results of geochemical analysis (XRF and ICP-MS), the volcanic rocks outcropping in the region have medium- to high-K calc-alkaline character. The mass and net mass change calculations indicate that 25.2 % volume increase in the altered zones mainly due to addition of K (9,93 g), P (0,46 g), Mg (16,74 g), Al, S, small amount of Si (5,89 g), and ore-forming elements. The presence of silicification, kaolinization and sulfate minerals such as alunite-jarosite in the extremely altered fault and fracture zones indicates that a hydrothermal system works in the region. Also, Ba, Sr, Pb, Bi and As enrichments in the extremely altered zones support the existence of the hydrothermal system. The system has led to the formation of clay beds, which can have economic potential due to intense hydrothermal alteration occurring in pyroclastic deposits.

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