Physics 125A Chapter Notes - Chapter 9.1, 9.2, 9.6: Volcanic Rock, Seismic Wave, Outer Core
Document Summary
Each planet must have looked very different than it does today when it was first born. Planetary geology: the study of earth and other worlds, includes solid worlds, like moons. How do we know about earth"s interior: seismic waves after earthquakes. Three layers of planets: core: highest density material. Differentiation in the past: we should expect smaller worlds to have correspondingly smaller cores. Geological activity: ongoing changes, volcanic eruptions, earthquakes, erosion, and other geological processes continue to reshape earth, making earth geologically active, interior heat is the primary driver of geological activity. How interiors get hot: interiors contain a lot of thermal energy, heat of accretion: as a planetesimal approaches forming a planet, its. Gpe is converted into thermal energy, causing it to accelerate. Upon impact, much thermal energy is converted into heat, adding to the thermal energy of the planet.