Forces Shaping the Earth Chapter 1 Section 3 Forces Shaping the Earth
Inside the Earth The earth has 3 layers. Core Mantle Crust
Core Center of the Earth Inner Core -Dense area consisting of hot iron mixed with rock and other metals. Outer Core – so hot that the metal melted into a liquid.
Mantle Layer of rock surrounding the core measuring about _______________ miles thick. Mantle has two parts: Inner mantle – solid - rock Outer mantle – liquid- melted rock What is melted rock known as _______________________.
Crust Uppermost layer of the earth Thin layer measuring only about ______________ miles thick Crust includes the ocean floors, as well as the 7 ____________________. Crust is thinner on the ocean floors, than it is under the continents.
Structure of the Earth
Forces Beneath the Earth Plate Tectonics – crust is not an unbroken shell but rather a series of plates, or huge slabs of rock.
Forces Shaping the Earth Tectonic Plates move in all different directions. Millions of years ago, the plates were connected scientists call this ____________. A: Pangea
Pangea
When Plates Meet
When Plates Meet Plates move in all different directions, they can move away, push against, or slide along side each other. Plates can smash into one another This forms _______________________ A: Mountains Himalayans in South Asia formed in this manner
Mountains
When Plates Meet Continental Plates and Ocean Plates move against each other Continental plates are heavier and go over the Ocean plate Lower plate causes pressure to build up which causes and volcanic eruption with magma Pressure also builds between the two plates, and then an earthquake can occur.
Volcanoes
Ring of Fire Huge area in the Pacific Ocean between Asia and the United States. Circle forms from the large amount of active volcanoes found there
When Plates Meet Earthquakes are sudden movements of the earth’s crust. Earthquakes can also occur when plates slide along side each other. The sliding motion causes pressure to build up, cracks begin to form. Fault line – cracks in the earths crust. San Andreas Fault in California is a huge fault line that causes many deadly earthquakes.
Earthquakes
Tsunami When an earthquake occurs underwater, it can cause a huge wave to form. Waves can be very deadly and reach several feet high.
Tsunami
Forces Shaping Landforms Weathering – the process of breaking surface rock into boulders, gravel, sand and soil. Causes of Weathering: Water Frost Chemicals Plants
Erosion Erosion – the process of wearing away, or moving weathered materials. Causes of weathering: Water Wind Ice –glaciers huge slabs of ice that change the land as they move over it. Erosion is earths scrub brush. Glaciers are earth’s sandpaper.