Wide spread zeolitization of the Neogene – Quaternary volcanic tuff in Jordan

Representative samples were collected from well exposed Neogene – Quarternary scoria cones of north east Jordan. The results of this study have led to the discovery of eleven new localities of zeolite associated with the volcanic tuff. The zeolitization process of the volcanic tuff in Jordan is widespread and of regional distribution. The identified zeolites are phillipsite and chabazite with subordinate associations of faujasite and analcime. The zeolitization process resulted from the transformation of sideromelane into palagonite by the reaction of the scoria with the circulating meteoric water. The variation in the Na/K, Na/Ca and Si/Al ratios of the circulating water was responsible for the variation in the mineralogy and chemistry of the zeolites and the associated authigenic minerals.