Earth Sciences 2240F/G : Chapter 7-9.docx

• School: Western University
• Department: Earth Sciences
• Course: Earth Sciences 2240F/G
• Professor: Ron Podesta

Document Summary

Pacific ocean- ocean floors spread causing eruptions (ring of fire) Volcanic rock decomposes quickly to produce rich soil. Yellow stone- erupted three times in usa causing no summer for two years with so much ash. Magma- molten rock, hot liquid, gases, scattered mineral crystals. Lava- magma when it is out on the surface. Pyroclastic- magma that blows out into the air from a violent eruption. Blobs of magma or very solid blocks or fine material. Ash- form of pyroclastic that is very fine but pulverized material. Volcanic rock- after the magma has been cooled or solidified. Igneous rocks- produced from volcanic or plutonic magma: (cid:160) viscosity: provides resistance to flow (opposite is fluid, temperature: high more fluid low-more viscous. Higher temperature the greater the atoms vibrate breaking bonds and creating a liquid. 900oc liquid would be 100,000 times more fluid than 600oc: volatiles (structure of h2o; role) Not symmetrical (one end + charge, the other end charge) dipolar.