EARTHSC 2GG3 Lecture Notes - Lecture 1: Volcanic Rock, Volcanic Ash, Silicate Minerals

• School: McMaster University
• Department: Earth Sciences
• Course: EARTHSC 2GG3
• Professor: John Maclachlan

Document Summary

Plate boundary - most likely spot for volcano occurrence. Most active volcanic area known as the ring of fire (indonesia, japan) is around the pacific ocean. Lava is molten rock on the earth"s surface. Pyroclastic debris - lava and rock fragments ejected in a volcanic eruption. Volcanic bombs: large masses thrown out of explosive volcanoes. Lapilli: smaller volcanic rocks, comes out of semi molten rocks. Volcanic ash: most destructive, climate effects, economic effects, etc. of volcanic ash, tiny shards of glass, dangerous to health. Volcano - hill or mountain produced by volcanism. Vent - opening through which eruption takes place. Caldera - depression is greater than 1 km wide. If there is a lot of magma in the volcano, it can potentially collapse on itself. Decompression - pressure exerted on hot rock is reduced, occurs at divergent boundaries, continental rifts and hot spots. Addition of volatiles - chemical compounds that lower the melting temperature of the rock.