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Explore the complexities of volcanic viscosity, geological viscosities, magma dynamics, and igneous formations. Learn about plate tectonics, common materials, and the driving forces behind volcanic eruptions. Dive into the anatomy of various volcanic structures worldwide.
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Viscosity • Units: pascal-seconds (kg/m-sec) • How many pascals pressure x how many seconds to squash fluid flat? • Viscous: Material flows as long as pressure is applied, however small • Pseudoviscous: Material flows after some threshold stress
What Drives Magma? • Magma is typically 10% lighter than equivalent solid rock • Why pressure inhibits melting • Buoyancy drives magma upward • Weight of rock around volcanic conduit > weight of magma • Gas pressure powers volcanic eruptions • Mafic (dense) rocks can sink in crust by viscous flow