MKTG 317 Lecture Notes - Lecture 2: River Engineering, Saguenay Flood, Snowmelt
11 Oct 2017
School
Department
Course
Professor
Document Summary
Pyroclastic flows: fast moving current of hot gas. 3 types of magma andesite, basalt (safest), rhyolite (higher water = more explosive), silicone + oxygen compounds: magma contains dissolved gases, volatiles; solubility increases as temp. increases. Spreading centres are ideal locations for volcanism because 1) they sit above high temp. asthenosphere 2_ the asthenosphere rock has a low percentage of sio2 3) the oceanic pull apart= allowing hot rocks to rise = lower pressure. Icelandic type: most peaceful, fissure eruptions because lava pours out of linear vents or long fissures. Lava domes: when the gas is depleted, gas poor, high viscosity magma slowly oozes out, a plug in the throat of the volcano. Explosive eruptions (from least to greatest): strombolian (somewhat), vulcanian, plinian. Stratovolcanoes: steep sided, symmetrical volcanic peaks built of alternating layers of pyroclastic debris, high viscosity andesitic to rhyolitic lava.
