ENV 110 Study Guide - Spring 2018, Comprehensive Midterm Notes - Plate Tectonics, Igneous Rock, Asthenosphere

• School: University of Portland
• Department: Environmental Studies
• Course: ENV 110
• Professor: Kali Abel

Document Summary

Stars are immense balls of incandescent gas: light years: is the distance light travels in one year, light travel around earth 7. 5 time in one sec. Sun is medium sized star orbited by 8 planets: our sun is about 99. 8% of our solar systems mass. Is a large body orbiting a star: spherical shape, cleared neighboring. Thea protoplanetary hits earth: collision debris form a ring around earth, coalesces and forms the moon. When earth becomes cool enough: moisture condenses and accumulates, the ocean comes into existence. Diffusion of core and mantel: molten ocean 4. 7 ga-4. 4ga. Early formation of earth crust: plate tectonics began during or just before the archean. First evidence of life: first undisputed fossils 3. 2 ga (possible first life 3. 8 ga, photosynthesis occurring. Global change: plastic asthenosphere permits tectonic plate motion, star warm enough to warm earth and atmosphere (habitable zone, liquid is possible allowing weathering and erosion, biotic evolution continually modifies the biosphere.