GLG 111 Lecture Notes - Lecture 4: Viscosity, Stratovolcano
Document Summary
Volcano- cone shaped structure created by the successive eruptions of lava and/or pyroclastic material onto earths surface. 50-60 volcanoes erupt each year- most are gentle eruptions. Not all volcanoes have the same physical features, but all are generated by the build-up of erupted materials. The form of a volcano is determined by the composition of its magma/lava. Shield volcano broad, domed structure volcano produced by the accumulation of basaltic lavas flat, cover large areas, may or nay not have a large caldera at the top. Cinder cone volcano- cone shaped made by accumulation of ejected lava fragments and pyroclastic material short, steep slopes small. Composite cone (stratovolcano) large, cone shaped volcano made from accumulation of gas rich intermediate and felsic lavas and pyro material steep with gentle sloping flanks tall, nearly symmetrical. Magma viscosity and factors that play into the style of eruption.
