زئوليت در سازند آقچاگيل منطقه مغان شمال غرب ايران

Zeolite in the Akchagyl formation in the moghan

formation in the form of ash, show no changes. Microscopic studies also show volcanic rock fragments are fresh and have not been changed to zeolite. Heulandite is formed by alteration of plagioclase feldespar during diagenesis. partially altered plagioclase to zeolite and remaining of polysynthetic twinning of completely altered pla­gioclase are the main evidences of feldsare alteration, low salinity of depositional environment and pore water as well as low PH are the main causes of these changes