EASC 108 Lecture Notes - Lecture 8: Mantle Convection, San Andreas Fault, Paleomagnetism
Document Summary
3rd planet from the sun (1au), 5th largest world. Sidereal rotation 23. 9 hours (solar day 24hrs) 78% n2, 21% o2, < 1% others 0. 004 co2. Smaller worlds cool off faster and harden earlier. Larger worlds remain warm inside, promoting volcanism and tectonics. Larger worlds have more erosion because gravity remains an atmosphere. Planets close to sun too hot for rain, snow, ice = less erosion. Hot planets have more difficulty retaining an atmosphere. Planets far from sun too cold for rain = limits erosion. Planets with slower rotation have less weather, less erosion, and a weak magnetic field. Planets with faster rotation have more weather, more erosion, and a stronger magnetic field. A planet"s outer layer of cool, rigid rock is called the lithosphere: it floats on the warmer, softer rock that lies beneath it. Earth divided into layers based on composition/mechanical properties. Motion of the continents can be measured with gps.