Class 2: Chapter 1 Ideas needed to understand the point of the class Earth Systems • Helps organize a set of processes as a distinct entity • Isolated: no interaction with other systems • Closed: exchange of energy only • Open: exchange of energy and matter Complete worksheet #1 • What is Earth system science? • Examining how different groupings of matter and energy operate and how changes in one system impacts other systems. • • • • Geosphere Atmosphere Hydrosphere Biosphere These systems are open because there is a transfer of energy and matter between systems. Explain each of these cycles or subsystems The hydrologic cycle The rock cycle Today’s class • Earth systems • Earth’s surface features – Features on the map, exercise • The scientific method • Geology as a science and evolution of ideas: uniformitarianism and catastrophism • Time and space Why are these concepts important to the class? Earth Systems • Understand when there is a change in one system, this impacts other systems • If there is a reduction of precipitation, this reduces the amount of erosion and sediment deposition. Earth’s surface features • Trends and patterns of topographic features are indicative of what processes are occurring within the Earth • Geographical features such as mountains and volcanoes adjacent to trenches Use either the physical map at the front of the room or map on pages 20 and 21 of the book. COMPLETE WORKSHEET Earth’s energy sources Internal heat • Remaining from the Earth’s formation • Decay of radioactive particles • Influences movement of tectonic plates • Provides energy for volcanic eruptions and earthquakes Sun • Drives the atmosphere, hydrosphere, weather and climate The Scientific Method • How new ideas are developed • The natural world behaves in a consistent and predictable manner. • A hypothesis or multi hypotheses are proposed, observations or data prove or disprove • Ideas evolve with new information • Most every overview or concept presented in this class is the result of many scientist’s work using the scientific method. History of geology as a science • New hypothesis and theories alter the evaluation of data – Theory of plate tectonics – Uniformitariansim versus catastrophism Ideas evolve with new information James Hutton: father of geology • Scottish engineer/farmer • 1785 • Observed that Earth’s processes are slow • Uniformitarianism: geologic processes that occur today also occurred in the past • The present is the key to the past Who cares? Why the big deal??? His observations, descriptions, hypotheses, and theories went against the accepted philosophies of the time. th 18 century Europe was strongly influenced by the Christian Church • Bishop Usher • Calculated the Earth’s age by adding the ages in the Bible • Irish Archbishop • 1654 • 4004 CE • Catastrophism: Earth formed by biblical type events William Whewell • Earth history also contains catastrophic events • 1850 • Catastrophism Geological ideas were based on the concept of uniformitarianism. Walter and Luis Alvarez • • • • Extinction of the dinosaurs 1980 Asteroid impact Catastrophism Today, uniformitarinism and catastrophism are accepted ideas Mississippi River Delta: slow deposition Volcanic eruption: Mt. Pinatubo, large event that lowers global temperatures by .7 degree Fahrenheit for two years. Time • Understand the enormous amount of time since the creation of the Universe, solar system, and Earth • Humans have not lived on this planet for a long time compared to the age of the Earth • Understand that mostly, Earth’s processes are very slow with an occasional large event Time Creation of matter: 14 billion years Tsunami: hours Change through time Geologic time: the most important contribution to the world Complete the 2nd page of the worksheet Space • Features presented in the class vary from microscopic to enormous Fossil diatom Orion nebula 100 light years in diameter Scale: 1 x 10-6 meters 1 light year = 6 trillion miles These concepts will be applied to most topics discussed in this class • Earth systems • Earth’s surface features – Features on the map, exercise • The scientific method • Uniformitarianism and catastrophism • Time and space