Archean felsic volcanic rocks often causes pyroclastic flow (hot, dense gas with volcanic fragments) instead of fluid lava flow. However, if the rhyolitic lava is still molten during eruption, it can behave and flow like fluid flow. Felsic lava flow and lava dome are the two common types of underwater deposits formed by Archean felsic volcanic rocks (Fig. 4). Documented Archean lava structures are distinctive from post-Archean felsic lava because underwater eruptions are so rare in post-Archean. The dacitic or rhyolitic lava flows are quenched right after the eruption. When water is in touch with the flow, the lava quickly cools down. Finally, The
Felsic Often the species of mafic minerals is included in the name, for instance, hornblende-bearing granite, pyroxene tonalite or augite megacrystic monzonite, because the term "granite" already assumes content with feldspar and quartz. The rock texture thus determines the basic name of a felsic rock. Felsic In geology, felsic refers to igneous rocks that are relatively rich in elements that form feldspar and quartz. It is contrasted with mafic rocks, which are relatively richer in magnesium and iron. Felsic refers to those rocks rich in silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen,