Unit One Earth Processes 6th Grade Science Review Theory of Plate Tectonics Continental Drift Plate Tectonics The Earth’s continents were once joined in a single large landmass that broke apart This land mass was called Pangaea Alfred Wegener proposed the theory of the continental drift Evidence to support the theory: rocks fossils Glacial deposits ocean-floor structures Convection currents in the Earth's mantle play a role in forming and destroying the oceanic crust. Rocks and Minerals Properties of Minerals Color Hardness Streak Luster Property of Color Color is the first thing someone notices when they view a mineral Red Yellow Property of Hardness Hardness can be tested through scratching Some common things used to test for hardness fingernail (2.2) copper penny (3.5) pocket knife or common nail (5.2) piece of glass (5.5) steel file or concrete nail (7.5) Property of Streak Streak is actually the color of the powder of a mineral. The proper way to test for streak is to rub a mineral across a tile of white unglazed porcelain and to examine the color of the "streak" left behind. Property of Luster Luster is a description of the way light interacts with the surface of a crystal - how it reflects light Pearly Luster Metallic Luster The Rock Cycle All rocks are made up of minerals The rock cycle shows how the three types of rocks form Click to see rock cycle Weathering and Erosion Breaking down of the earth’s crust into sediments Earthquakes Occur along plate boundaries Earthquake activity is measured using a seismograph The seismogram is the reading that is produced Connect to website - click here Volcanoes Occur along plate boundaries Eruptions create dust and ash which effects weather and climate Click picture to learn more Earthquakes and Volcanoes The Pacific Ring of Fire is an area of frequent earthquake and volcanic eruptions encircling the basin of the Pacific Ocean Mountains Contour maps Lines on the map are the contour intervals Contour intervals are used to determine elevation points Steepest slope - contour lines are close together Gentlest slope - contour lines are far apart Review website we did in class - click picture Fun Interactive Websites Click on topic below Earth Processes and Plate Tectonics Rock Cycle Volcanoes The End I hope this presentation helped you review for the Unit Test!!