ESCI 401 Lecture Notes - Lecture 12: Pegmatite, Tephra, Viscosity

• School: UNH
• Department: Earth Sciences
• Course: ESCI 401
• Professor: Boettcher, Margaret S.

Document Summary

Groundwater circulation: lava flow, pyroclastic debris i, gas i. Tephra: what are three products of volcanic eruptions, what is the primary physical parameter of a lava flow that determines how fast and how, unconsolidated deposits of grains from pyroclastic debris far it will flow, viscosity i. A measure of fluids resistance to flow: honey is more viscous than water, temperature i. i, gas content, composition. Felsic makes the viscosity go up i: mafic makes the viscosity go down, how does a basaltic flow differ from a rhyolitic flow, basaltic lava flows i. ii. iii. iv. v. vi. Produces at mid-ocean ridges and continental hot spots. : pahoehoe lava: ropy texture, high fluid lava that spreads in sheets and a glassy skin forms as it cools vii. viii. ix. Columnar jointing: feels like you"re stepping on glass when you step on it, flows slowly, crusts over, flows again, during the final steps of cooling, lava flows contract and may.