Energy Sources for Disasters / Geologic time / Earth Materials Energy Sources of Disasters -disasters occur where and when Earths natural processes concentrate energy and then release it, killing life and causing destruction -growth of worlds population -> more people are affected by natural disasters since more people are occupying areas close to or at hazardous places -natural hazards are caused by the energy sources that fuel Earth processes -internal energy and external energy Internal energy: within Earth a) impact energy b) gravitational energy c) radioactivity External energy: exterior/surface of Earth a) the sun Four Primary Energy Sources that fuel Earth processes -these make Earth an active body: 1) the impact of extraterrestrial bodies (impact energy) 2) gravity (gravitational energy) 3) Earths internal heat 4) the sun 1) Impact energy -impact of extraterrestrial bodies -asteroids and comets -impacts were abundant and important Early in Earths history -heat energy -planetary rings, objects hurling in space Rocky chunks -> stoney meteorite Metallic chunks -> Fe (iron) meteorite Icy chunks -> comets 2) Gravity (gravitational energy) -an attractional force between bodies -at equal distances, the greater the mass of a body, the greater its gravitational force (ex. Bigger falls harder or more mass, more you weigh) Geol 303 (Natural Disasters) Study Guide - Exam 1 Understand the nebular hypothesis for the formation of the Earth and the solar system. Is the Earth a terrestrial planet or a Jovian planet? What is the difference in these two planetary types? How old is the Earth? Where does the heat in the Earth's interior come from? How was it used to differentiate the early earth into a series of nested layers? Know what these layers are, how they differ in density and composition, and how they formed.

Have a thorough understanding of the cross-section of the upper mantle and crust and the relationship between the asthenosphere and lithosphere. How do these later two layers differ from one another? What are the two most common elements in the Earth's crust? What is a mineral? Know the difference between absolute and relative dating, and how each to determine each. What is meant by half life? What is meant by the Curie point? What is the difference between a continental shelf and a deep oceanic trench? Have a thorough understanding of plate tectonics, including the nature of the plate boundaries, and the specific role of particular scientists in evolution of thought leading to the plate tectonic theory. What is the difference between continental drift, seafloor spreading, and plate tectonics? Know the three different types of convergent plate boundaries, and examples of each. What is Pangea? On what plate is San Diego located? What is the composition of both oceanic and continental crust? Which is denser? How is oceanic crust created and where does this take place? Where is oceanic crust destroyed; i.e., consumed back into the mantle? Have a thorough understandingof the fundamental concepts controlling weather (e.g., atmospheric heating, the Coriolis effect, global wind patterns, and the movement of air masses and weather fronts). Understand the nature of the global belts of high and low pressure and the convection cells associated with each. What is the jet stream? What differentiates a lowpressure system from a high-pressure system? In which system is it likely to rain? Why? In which is it likely to have clear skies and dry conditions? Why? In what way do regional pressure systems control the global movement of wind? Have a thorough understanding of the nature of thunderstorms, hail storms, tornadoes, and hurricanes. What factors control the generation of each? Where does the energy for severe types of weather come from? Where in the U.S. are you more likely to experience thunderstorms? . . . hail storms? . . .tornadoes? What relationship does the jet stream have to the generation of hail storms and tornadoes? How would you determine how far away you are from a thunderstorm? How are tornadoes produced? What is the difference between a hurricane and a cyclone or a typhoon? How does a hurricane differ from a tropical storm or a tropical depression? In what directions do hurricanes rotate in the northern and southern hemispheres? Why? How does the eye and eye wall of a hurricane differ from the rest of the storm? What is the storm surge?