Geology 150 Earth Revealed Introduction
Evolution of the Earth Big Bang – 15 b.y. Solar Nebula Cooling and Condensation of tiny particles Repeat collisions Accretion into planets
Our Solar System Composed of Sun, 9 planets, asteroids, comets, and moons –Sun is at the center –Inner planets Terrestrial (rocky) –Outer planets Jovian (gas) (1) Mercury, (2) Venus, (3) Earth, (4) Mars (1) Jupiter, (2) Saturn, (3) Uranus, (4) Neptune –Outermost planet Pluto
Earth
What is Geology? The science that seeks to understand planet Earth
Earth’s system Group of interacting parts that form a complex whole Hydrologic Cycle Rock Cycle
Earth’s Spheres Biosphere –All living organisms and their habitats Hydrosphere –H 2 O in oceans, rivers, lakes, ice, groundwater Atmosphere –Gaseous envelope surrounding Earth Geosphere –Solid Earth
Geology I.Physical Geology –Materials that compose the Earth and the processes that operate beneath and on its surface II.Historical Geology –The origin of Earth and its development over time
History of Geology Catastrophism –Earth’s landscape had been shaped by great catastrophes
Modern Ripples History of Geology “The present is the key to the past” Uniformitarianism –Geologic processes operating today, operated in past Fossilized Ripples Modern Mudcracks Fossilized Mudcracks
People and Geology Natural Hazards –Natural processes that become hazards when people live where they occur
Natural Hazards Earthquakes
Natural Hazards Volcanoes Nevado del Ruiz, Columbia, 1985; 25,000+ perished
Natural Hazards Volcanoes Weed, California; Mount Shasta
Natural Hazards Landslides La Conchita, California
Natural Hazards Floods
Natural Hazards Tsunamis