Earth’s Spheres, Landforms and Physical Processes What does it all mean? ©2012, TESCCC

©2012, TESCCC

©2012, TESCCC

Earth’s Spheres Atmosphere: located right above the Earth’s surface and includes layers of gases (clouds, air pollution, sand storms, hurricanes, etc.) It protects us by absorbing solar radiation. Biosphere: life on land, rivers and oceans (Biomes) deserts, forests, grasslands Hydrosphere: water in liquid and solid state (oceans, glaciers, snow, lakes, rivers, etc.) Lithosphere: solids of the Earth (rocks, soils, landforms, etc.) ©2012, TESCCC

Dissecting the Earth Inner core- very hot and solid Outer core- hot molten liquid Lower mantle- largest area, sticky-thick liquid Upper mantle- solid rock Crust- thin top layer of Earth’s surface Atmosphere- air; layers of gases, clouds Lithosphere- solids of the Earth; rocks, soil, landforms Hydrosphere- water in liquid or solid state; oceans, glaciers, snow Biosphere- life on land or in water; different biomes or habitats such as deserts or forests ©2012, TESCCC

Dissecting the Earth ©2012, TESCCC

Plate Tectonics: View direction of the arrows showing movement of the plates. What can you deduce from this image? ©2012, TESCCC

Movement Along Plate Boundaries Converging- Plates moving toward one another; plates colliding Subduction- Plates moving underneath each other Divergent- Plates moving away or apart from one another. Also known as “spreading” Transform faulting- Plates moving side to side or sliding past each other ©2012, TESCCC

Converging Consists of two types of plate boundaries… *Continental-continental (mountains) *Oceanic-oceanic (volcanic mountains and ocean trenches) Oceanic-oceanic plates are heavy, and move under the lighter continental plate. This in turns causes subduction. All convergent plates experience landslides and volcanic mudslides ©2012, TESCCC

Subduction Plates moving underneath each other The subducted crust is always oceanic while the overriding crust may or may not be oceanic. Subduction zones are often noted for their high rates of volcanism, earthquakes and mountain building, also known as orogenesis. ©2012, TESCCC

Divergent Plates moving apart from each other On land, this is called a rift valley, and in the ocean it is called mid-oceanic ridge Block-vaulted and volcanoes form here (When the continental crust fractures, large blocks of crust can drop into the space that opens up) Earthquakes are experienced here ©2012, TESCCC

Transform faulting Plates moving side by side Produces earthquakes Relative motion is predominantly horizontal Transform faults end abruptly and are connected on both ends to other faults, ridges, or subduction zones While most transform faults are hidden in the deep oceans where they form a series of short zigzags accommodating seafloor spreading, the best-known (and most destructive) are those on land at the margins of tectonic plates ©2012, TESCCC

Pangaea Scientist Alfred Wegner theorized that at one time there was one huge super continent- Pangaea, that broke apart and separated into our seven (7) current continents The continents continue to drift even today Continental drift- Pangaean plates spliting and breaking apart several times to form the continents we know today; tectonic plates In the 1960’s, scientist found eveidence on the sea floor that suggested that it was spreading and pushing the continents apart. ©2012, TESCCC

Our next supercontinent, maybe? The Earth has been covered by giant combinations of continents, called supercontinents, many times in its past, and it will be again one day in the distant future. The next predicted supercontinent, dubbed Amasia, may form when the Americas and Asia both drift northward to merge, closing off the Arctic Ocean, researchers suggest. Conventional models of how supercontinents evolve suggest they form on top of the previous supercontinent, known as introversion, or on the opposite side of the world from that supercontinent, known as extroversion. Under these models Amasia would therefore either form where Pangaea once was, with the Americas meeting with Asia to close off the Atlantic Ocean, or form on the other side of the planet from where Pangaea was, with the Americas merging with Asia to close off the Pacific Ocean. ©2012, TESCCC

Ring of Fire The Ring of Fire is the circle of volcanoes bordering the Pacific Ocean. An arc of islands east of China marks where the Pacific, Philippine and Eurasian tectonic plates meet. Most of the mountainous islands, including Taiwan and Japan, were formed by volcanic activity. Plate movements cause frequent earthquakes that can generate tsunamis and violent volcano eruptions. ©2012, TESCCC

Now lets read… Open your books and read pgs 26-29 and pgs 37-41 OH…. And you will have homework  ©2012, TESCCC