Where are felsic volcanoes found?
Examples include the Andes Mountains of South America, Cascade Range in North America, and the Japan Islands in the western Pacific. Because if its relatively high viscosity, felsic magma is resistant to flow and tends to plug volcanic vents, causing a buildup of pressure that may release violently.
Where is the most felsic volcanism found?
Divergent plate boundaries are where we find most felsic volcanism.
Where do felsic stratovolcanoes form?
Stratovolcanoes are common at subduction zones, forming chains and clusters along plate tectonic boundaries where oceanic crust is drawn under continental crust (continental arc volcanism, e.g. Cascade Range, Andes, Campania) or another oceanic plate (island arc volcanism, e.g. Japan, Philippines, Aleutian Islands).
What is felsic lava and where does it come from?
Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. Felsic magma or lava is higher in viscosity than mafic magma/lava.
Where does felsic magma come from?
It has been suggested that felsic magmas found at subduction-zone volcanoes are produced by mechanisms including fractional crystallization with or without crustal assimilation8, partial melting of the crust9,10, and partial melting of metasomatised silica-excess pyroxenite mantle11,12.
Do shield volcanoes have mafic or felsic lava?
Magma composition determines both eruption type and volcano type. Composite cones are built of felsic to intermediate lava and shield volcanoes of mafic lava. Cinder cones are made of small fragments of a variety of compositions usually from a single eruption.
What is felsic lava?
Felsic lavas are low temperature lavas because lower temperatures are required to keep felsic minerals molten (and if it was hotter it would have incorporated more iron and magnesium in comparison to silica). So, mafic lavas are hot , low in silica and volatiles, and have relatively low viscosity.
What are felsic rocks high in?
In geology, felsic is an adjective describing igneous rocks that are relatively rich in elements that form feldspar and quartz. Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium.
Where are mafic magmas most likely to be found?
Mafic magmas are usually produced at spreading centers, and represent material which is newly differentiated from the upper mantle. Common mafic rocks include basalt and gabbro.
What plate boundary do stratovolcanoes form?
Composite volcanoes, also known as stratovolcanoes, are found on convergent plate boundaries , where the oceanic crust subducts beneath the continental crust.
What are stratovolcanoes composite formed from?
Key Takeaways: Composite Volcano Composite volcanoes, also called stratovolcanoes, are cone-shaped volcanoes built from many layers of lava, pumice, ash, and tephra. Because they are built of layers of viscous material, rather than fluid lava, composite volcanoes tend to form tall peaks rather than rounded cones.