Astronomy 1021 Chapter Notes - Chapter 7: Subduction, Scientific Modelling, Outer Core

• School: Western University
• Department: Astronomy
• Course: Astronomy 1021
• Professor: Jan Cami

Document Summary

Volcanoes and earthquakes are 2 processes that act to reshape the earth"s surface. Also on rare occasions asteroids or comets slamming into earth cause far greater change. Gradual changes due to erosion (wind, wave/water, rain) The terrestrial worlds probably all looked the same when they were young because they are all made of rock. Earth is geologically active meaning its surface is constantly being reshaped by volcanic eruptions, earthquakes, erosion, and other processes. Most of these take place deep under earth"s surface. Seismic waves vibrations that travel both through the interior and along the surface after an earthquake. Comparing overall average density to surface rock density tells us how dense the inside of a planet must be. Measuring a world"s gravity tells us about mass distribution. Studies of magnetic fields tells us about interior layers. Volcanic rocks tell us about interior composition. Rock can vary in strength, breaks cleanly when pulled quickly but stretches and deforms when pulled slowly.