form into homogenic phases at the temperatures of 321.5°С, 204°С and 185°С, respectively. The. amount of fluid salt is 1.7-6.7 weight % NaCl eq. 4. f ГЕОЛОГИЙН АСУУДЛУУД 17 (519) 2019. Stable oxygen isotope is (δ18O 23.6‰) for the first generation quartz whereas it is (δ18O.