The Structure of the Earth Continental Puzzle • Pangaea – theory of continental drift • Continents—landmasses above water on Earth Inside the Earth • The Core is the center of the earth • Outer core is liquid; inner core is solid • The Mantle surrounds the core (outer core) • Magma—molten rock that forms in the mantle • Crust—thin layer of rock at Earth’s surface Continued . . . NEXT

On and Above the Earth •Atmosphere is the layer of gasses surrounding the earth: - contains oxygen - protects Earth from radiation, space debris • Lithosphere—solid rock portion of Earth’s surface, forms ocean floor • Hydrosphere—water elements on Earth including atmospheric water • Biosphere—atmosphere, lithosphere, hydrosphere combined

• Motion of ocean helps distribute heat on the planet Bodies of Water Ocean Motion • Motion of ocean helps distribute heat on the planet 2 Lakes, Rivers, and Streams • Lakes hold more than 95% of the earth’s fresh water • Freshwater lakes were created by glaciers • Saltwater lakes form when outlet to sea is cut off • Tributaries are smaller and feed into rivers Ground Water • Ground water— water held in the pores of rock NEXT

• Landforms are naturally formed features on Earth’s surface • Topography —the configurations and distribution of landforms NEXT

• Tectonic plates are massive, moving pieces of Earth’s crust Plate Tectonics The Earth Moves • Tectonic plates are massive, moving pieces of Earth’s crust Plate Movement •  Plates move in one of four ways: - moving apart - subduction, going under another plate - collision - sliding past each other Continued . . . NEXT

• An earthquake occurs when plates grind or slip at a fault line Faults & Earthquakes • An earthquake occurs when plates grind or slip at a fault line • A seismograph detects earthquakes and measures the waves they create Earthquake Locations • Epicenter —the point directly above focus on the earth’s surface • Richter Scale —numeric scale showing relative strength of earthquake Tsunami • Tsunami, a giant ocean wave, begins at epicenter of an earthquake: - travels at up to 450 mph - waves of 50–100 ft. or higher Continued . . . NEXT

Volcanoes The Explosive Earth • Volcano—underground materials pour from crack in the earth’s surface • Eruption—lava, gases, ash, dust, explode from vent in Earth’s crust Ring of Fire • Ring of Fire —zone around rim of Pacific Ocean that contains many volcanoes and hot springs • Creates fertile soil Continued . . . NEXT

• Weathering —processes that alter rock on or near the earth’s surface • Mechanical weathering —processes that break rock into smaller pieces • Examples: frost, plant roots, road construction, mining • Chemical weathering —interaction of elements creates new substance • Example: when iron rusts it reacts to oxygen in air and crumbles Continued . . . NEXT

• Erosion —when weathered material moves by winds, water, ice, gravity 4 Water Erosion - river deposits sediment at ocean, creates delta —fan-like landform Wind Erosion Glacial Erosion Continued . . . NEXT