Thermal Reaction Of Antigorite: A XRD, DTA-TG Work

Yıl 2006, Cilt: 133 Sayı: 133, 41 - 49, 01.02.2006

Gökçe Gürtekin Mustafa Albayrak

Öz

 It is very important to determine the stability limits of serpentine minerals for investigation of geologic
processes taking place in the oceanic lithosphere which consists of serpentinized peridotites. As a result of
temperature increase in the subducting oceanic lithosphere, thermal decomposition of serpentine minerals and
new mineral formations have a great effect on geologic processes related to subducting plate. In this study, serpentine
minerals (antigorite) collected from the Konya-Çayýrbaðý region were dehydrated under constant atmospheric
pressure, then mineralogical changes were determined by using X-Ray diffraction and DTA-TG analyses
and finally the stability limits of antigorite was determined. Dehydration reactions on antigorite started at approximately
100-150°C, dehydroxilation reactions started at approximately 550°C and beyond this temperature
forsterite started to crystallize from antigorite+brucite. Association of antigorite+forsterite continued until 650°C at
which enstatite started to be formed. During all the reactions, which were carried out at the atmospheric pressure,
talc was not formed but some H2O and amorphous silica were released. Dehydroxilation reaction on antigorite
occurred between 550°C and 690°C and antigorite was stable until 650°C-690°C.

Anahtar Kelimeler

XRD, DTA-TG, Antigorite, Dehydration, Dehydroxilation

Kaynakça

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