The Lithosphere Mr. Norris

Day 1 Objective: Objective: – I can explain how the Earth is structured – I can explain how the material of earth is changed

Layers of the Earth Defined by composition 3 Major Zones – Crust – Mantel – Core

The Crust Thin, rocky outer layer Either oceanic or continental – Oceanic is 7-km thick – Continental is 8-75 km thick

The Mantle 82% of Earth’s volume 2890-km thick Solid rock at the top Liquid rock at the bottom

The Core Composed of an iron-nickel alloy Extreme pressure found at the center

Layers based on Physical Properties Lithosphere – Crust and Upper most mantle – Cool, rigid shell – 100-km thick Asthenosphere – Below the Lithosphere – Soft, comparatively weak layer – Rocks close to melting

Outer Core – Liquid layer – 2260-km thick – Metallic iron flow creates Earth’s magnetic field Inner Core – Solid layer – Radius of 1220-km – High temperature – High pressure – Mostly nickel

What is a ROCK? Solid mass of minerals or mineral matter that naturally occurs as part of out planet Three types – Igneous – Sedimentary – Metamorphic

Types of Rocks Igneous Rock – Forms when lava or magma cools Sedimentary Rock – When existing rocks are broken down into pieces then compacted and cemented together Metamorphic Rocks – When existing rocks are changed by heat and pressure

What is the ROCK CYCLE? Origin of the three basic rocks and interrelatedness of Earth’s materials and processes

The Rock Cycle

DAY 2 Objective: Objective: – I can explain about the theory of plate tectonic – I can describe plate interactions

What is Continental Drift? Proposed by Alfred Wegener Stated that the continents had once been joined to form a single supercontinent Supercontinent was called Pangaea

What did the Theory Says? Occurred 500 million years ago Pangaea broke apart 200 million years ago Continents “Drifted” (moved) to present positions Continents “broke” through the oceans North America and Africa split 135 million years ago

Evidence of Continental Drift Shorelines look like they fit together Same fossil organisms found on different landmasses Several mountain belts end at one coastline, only to reappear on a land mass across the ocean Ancient Climates relate

The Theory of Plate Tectonics Earth’s outer shell consists of individual plates Plates interact in various ways when they move along

Plate Boundary Activities Earthquakes Volcanism Mountain Building Sea Floor Spreading

Earth’s Major Plates Top 7 – African – Antarctic – Eurasian – Australian-Indian – North American – Pacific – Southern American Other Plates – Arabian – Caribbean – Cocos – Nazca – Phillippine – Scotia

DAY 3 Objective Objective – I can explain how the plates interact with each other

Types of Plate Boundaries Divergent Boundary Convergent Boundary Transform Fault Boundary

Divergent Plate Boundary When two plates move apart Also called spreading centers New crust is created (mainly seafloor) – Known as sea floor spreading Causes Ocean Ridges and Rift Valleys (on continents)

Convergent Plate Boundary Two places move towards each other 3 versions – Oceanic-Continental – Continental-Continental – Oceanic-Oceanic

Oceanic-Continental Convergent Boundary Oceanic plate goes beneath the continental plate Causes – Subduction zones – Trenches – Continental Volcanic arcs (ex: The Andes)

Continental-Continental Convergent Boundary Two plates continental plates collide Causes Mountains to forms – Ex: Appalachians, Himalayas, Alps

Oceanic-Oceanic Convergent Boundary Once oceanic plate goes beneath another oceanic plate Causes Volcanic Island Arc – Ex: Aleutian Islands

Transform Fault Plate Boundary Two plates grind past each other No production or destruction of lithosphere Causes Earthquakes – Ex: San Francisco

DAY 4 Objective: Objective: – I can explain how faults differ – I can explain the relation between boundaries and plate tectonics

What Causes Plate Movement? Convective Flow – The circulation of magma that pushes & pulls plates Driving Force is heat

What is a Fault? Fracture in Earth where movement has taken place Most times near Plate Boundaries

Parts of a Fault Hanging Wall – Rock above the fault line Foot Wall – Rock below the fault line

What are the types of Faults? Normal Reverse Thrust Strike-Slip

Types of Faults Normal Fault – Occurs when the hanging wall block moves down relative to the footwall block Reverse Fault – Occurs when the hanging wall block moves up relative to the footwall block

Thrust Fault – A reverse fault with dips of less than 45 degrees Strike-Slip Fault – Movement is horizontal and parallel trend of the fault surface

Evidence of Plate Tectonics 1.Paleomagnetism – Most persuasive evidence – Ancient magnetism found in the rocks – Records show a shift in the poles

2.Earthquake Patterns – Connection between deep-focus earthquakes and ocean trenches 3.Ocean Drilling – Young rocks are near ocean ridge crest – Oldest rocks are near the continental margins

4.Hot Spots – A concentration of heat in the mantle capable of producing magma, which rises to Earth’s surface – Supports that the plates move over Earth’s surface – Ex: Hawaiian Island Chain