WIDESPREAD SECONDARY CA GARNET AND OTHER CA SILICATES IN THE GALWAY GRANITE AND ITS SATELLITE PLUTONS CAUSED BY FLUID MOVEMENTS, WESTERN IRELAND

Widespread secondary andradite-grossular-hydrogrossular garnet, epidot e, prehnite and titanite occur throughout the Galway Granite and its s atellite plutons (Roundstone; Inish; Omey and Letterfrack) and even in some of the country rocks several kilometres from the granites. These minerals are not found in low CaO (< 1%) granites. They formed as res ult of secondary fluid movements which altered the biotite, plagioclas e and hornblende and also produced sericite and chlorite.