Natural zeolites mineralization in the Oligocene-Miocene volcanosedimentary succession of Central Sardinia (Italy)

摘要

Investigations performed on the Cenozoic volcano-sedimentary sequence of Central Sardiniarecognized widespread secondary mineralization processes, differently affecting the volcanic andsedimentary units cropping out in the region. Mineralogical studies evidence the presence of a mainzeolite mineral association consisting of clinoptilolite and mordenite, locally attaining economicconcentrations. Chemical composition of mordenite and clinoptilolite is strongly correlated with therhyodacitic glassy precursor. Secondary mineralization process which affected the volcaniclastic andepiclastic deposits, enables to identify the most interesting areas, as far as zeolite grade is concerned.Up to now, available data are not sufficient for a exhaustive definition of the complex and articulatedminerogenetic processes which originated the zeolitization .