The patterns of the predicted prospective target areas for IOCG deposits are defined mostly by neighboring to NE-SW trending faults, vicinity to
pyroclastic rocks (mainly tuff) and Au geochemical anomaly (Fig.
The basaltic and andesitic volcanic lavas and
pyroclastic rocks are deposited in the sedimentary basin in which magmas are enriched in iron and to some extent manganese.
Vent-filling
pyroclastic rocks of the mendanha, the Itauna, and the Cabo Frio Island, State of Rio de Janeiro, Brazil, and their formation process based of the conduit implosion model.
In general, extrusive and
pyroclastic rocks that formed on earth's surface have much higher Q values; hypabyssal rocks that formed near the surface have moderate Q values, whereas the plutonic rocks have the lowest Q values (Table 2).
U., 1984,
Pyroclastic Rocks: Berlin, Springer-Verlag, 472 p.
The Beulah Camp Formation comprises reddish-maroon, coarse- to fine-grained felsic and minor mafic
pyroclastic rocks, chiefly felsic lithic-crystal tuff.
The fragmented magma gives rise to
pyroclastic rocks, not lava flows.
These rocks include basaltic-andesitic lavas volcanoclastic and
pyroclastic rocks. The lavas generally have porphyritic texture with phenocrysts of plagioclase hornblende and pyroxene present in the greenish color chlorite mass.
The present study reports the laboratory simulation of the hydrothermal alteration of Neogene sedimentary and
pyroclastic rocks exposed around the Sochagota Lake (Paipa, Boyaca) to zeolites to understand the geological conditions controlling their formation.
Apart from magmatic rocks, the Lower Silesian basaltoid formation includes as well
pyroclastic rocks, such as: volcanic breccias, tuffs, and tuffites.