MEA101 - Physical Geology Module 2 PDF

MEA101 - Physical Geology Module 2: The Changing Solid Earth (and the origin of North Carolina) 1 Complete Learning Journal #2 before examining material that follows. Review the learning objectives b...

MEA101 - Physical Geology Module 2: The Changing Solid Earth (and the origin of North Carolina) 1 Complete Learning Journal #2 before examining material that follows. Review the learning objectives below that relate to the Learning Journal activities and consider how confident you are that you could successfully complete each task. Module 2, Part 1: Learning Journal #2 Learning Objectives I can accurately sketch to the relative positions of Earth’s main compositional layers (the crust, mantle, and inner and outer core). I can draw a labeled sketch of the components of the lithosphere and asthenosphere. I can describe the principal differences between Earth’s compositional layers. I can explain Wegener’s continental drift hypothesis and his supporting observations. I can explain why some scientists did not agree with the concept of continental drift. I can describe the reasons behind the development of the “land bridge” hypothesis and identify the observations necessary to falsify it. 2 1  Sample Answer: Learning Journal Question #5 In the early 1900’s, scientist Alfred Wegner proposed the hypothesis that the continents were once joined together in a single “supercontinent”, and that this land mass broke apart before the continents “drifted” to their current positions. Summarize the three most important observations that Wegner used to support his continental drift hypothesis. Alfred Wegener supported his theory of the continental drift using the arguments that all the continents when placed by each other fit together, there are similar fossils on all of these continents, and it explained the glacial deposits in unusual places. Wegener believed that if placed together correctly Africa, South America, Antarctica, India, Madagascar, and Australia all fit together. Today scientists do agree that all these pieces do fit together into what they now refer to as Gondwana. Wegener also studied the distribution of plant in animal fossils in all of these places and found that they all have similar species supporting the idea that the continents were joined at one point in time. Finally he made notice of the fact that there were glacier deposits in all of these places, where now and in Wegener's lifetime were far too warm to have glaciers present supporting the fact that these continents must have been in other locations from where they currently are. This is an example of an excellent response to the short answer question from the 3 learning journal. Try to be as comprehensive in your responses. Learning Journal Review Assessment Continental Drift How is fixing this plate similar to Wegener’s methods of assembling the continents into Pangaea? 4 2  Learning Journal Review Assessment Which of the images below best approximates the relative thicknesses and distribution of Earth’s core, mantle, and crust? 1. Big core, 2. Small core, 3. Big core, 4. Small core, thin crust thick crust thick crust thin crust 5 Review the learning objectives below that relate to the material to be discussed in the slides that follow. Your should be able to successfully complete these tasks when you have finished reviewing the related course resources (e.g., slides, videos, maps). Module 2, Part 1: Course Learning Objectives I can explain the source of internal heat that drives plate tectonic processes I can describe the principal characteristics of Earth’s compositional layers I can identify the distributions of the principal features of Earth’s surface I can write a description of a “tectonic plate”. 6 3 LO: I can explain the source of internal heat that drives plate tectonic processes Earth’s Formation and Internal Heat Earth formed from the accumulation of dust and gas, and collisions of smaller planetary bodies. Asteroids Uranus Driven by gravity, Jupiter Earth’s dense Sun Mars Neptune metallic core Venus Saturn formed as iron Orbit of Mercury Earth planets: sank to the nearly and Moon circular center. Less dense rocks slowly cooled to form 7 outer layers of Earth’s mantle and crust. LO: I can explain the source of internal heat that drives plate tectonic processes Earth’s Formation and Internal Heat Earth’s interior is still losing heat from the formation process but most of the heat from the planet’s interior is generated by radioactive decay of elements in the core and mantle. This heat flows through Convection drives Earth’s Earth’s interior largely by internal motions that: convection. Generate the planet’s magnetic field Rearrange the oceans and continents Produce mountains and volcanoes, and generate earthquakes 8 Watch Simple and Complex mantle convection videos linked to class Moodle site. 4 LO: I can describe the principal characteristics of Earth’s compositional layers Some Layers Are Stronger than Others Oceanic crust Continental crust Lithosphere (stronger) Uppermost mantle Asthenosphere (weaker) Lithosphere = crust + uppermost mantle Asthenosphere = layer in uppermost mantle hot and weak; mostly solid 9 LO: I can describe the principal characteristics of Earth’s compositional layers Match each of the three letters with one of the listed features. B C A Mantle lithosphere A Continental crust B Asthenosphere C Oceanic crust 10 5 LO: I can describe the principal characteristics of Earth’s compositional layers Plate Tectonics Animation Southern Atlantic opening 140 (Myrs-present) Examine the figure and predict which parts of the image best represent the continental crust, oceanic crust, lithosphere, and asthenosphere? 11 LO: I can describe the principal characteristics of Earth’s compositional layers Name the feature X labeled X on the image. A. Continental crust B. Oceanic crust C. Lithosphere D. Asthenosphere 12 6 LO: I can identify the distributions of the principal features of Earth’s surface Earth’s Surface Features In the decades following the presentation of the continental drift hypothesis, key observations about the Earth features contributed to the development of the theory of plate tectonics − Seafloor topography − Volcanoes − Earthquakes 13 LO: I can identify the distributions of the principal features of Earth’s surface Label the main features on Earth’s surface Oceanic fracture zones Continental shelves Island arcs Mountains Linear island chains Deep ocean trenches Mid-ocean ridges How are these features related to the continents and oceans? 14 7 LO: I can identify the distributions of the principal features of Earth’s surface Where are earthquakes (yellow dots) located relative to main features of Earth’s surface? 15 LO: I can identify the distributions of the principal features of Earth’s surface Where are earthquakes (yellow dots) located relative to main features of Earth’s surface? Island arcs Mountain belts Trenches Mid-ocean ridges 16 8 LO: I can identify the distributions of the principal features of Earth’s surface Where are active volcanoes (orange triangles) located relative to main features of Earth’s surface? 17 LO: I can identify the distributions of the principal features of Earth’s surface Where are active volcanoes (orange triangles) located relative to main features of Earth’s surface? Island arcs next to trenches Linear chains of oceanic islands Red Sea and East Africa Mountain belts Mid-ocean ridges (not all shown) next to trenches 18 9 LO: I can write a description of a “tectonic plate” Earth’s surface can be divided into “plates” on the basis of tectonic activity Earthquakes, volcanism, or mountain building = tectonic activity Belts of tectonic activity divide lithosphere into tectonic plates 19 LO: I can identify the distributions of the principal features of Earth’s surface Use the map to identify at least three locations found along: 1. Oceanic ridges 2. Oceanic trenches 20 10 LO: I can write a description of a “tectonic plate” Some Layers Are Stronger than Others Oceanic crust Continental crust Lithosphere (stronger) Uppermost mantle Asthenosphere (weaker) Lithosphere = crust + uppermost mantle = tectonic plate Trenches and/or = boundaries between plates oceanic ridges 21 LO: I can write a description of a “tectonic plate” Plate Tectonics Rigid lithosphere is divided into pieces = tectonic plates 22 11 LO: I can write a description of a “tectonic plate” Plate Tectonics Rigid lithosphere is divided into pieces = tectonic plates 23 LO: I can write a description of a “tectonic plate” Plate Tectonics Oceanic ridges and trenches represent most plate boundaries Plates composed of both oceanic and continental lithosphere, e.g., South America Most of the major geologic processes occur along the boundaries between plates How is plate tectonics Rigid lithosphere is divided different from into pieces = tectonic plates continental drift? 24 12 LO: I can write a description of a “tectonic plate” How many tectonic plates are pictured along the bottom edge of this image? 25 LO: I can write a description of a “tectonic plate” Andes mountains with mid-ocean ridge in Atlantic volcanoes and earthquakes Ocean (earthquakes, few along edge of continent volcanoes) Active continental margin Ridge is plate boundary Plate 1 Plate 2 Plate 3 03.09.b1 Oceanic plate descends below trench at western edge Shelf along eastern edge of of continent continent - not a plate boundary Trench is plate boundary Passive margin – no earthquakes, no volcanoes 26 13 LO: I can write a description of a “tectonic plate” Examine the image and label examples of tectonic plates, oceanic trenches, oceanic ridges, active and passive margins. 27 LO: I can write a description of a “tectonic plate” Define Key Terms Write a one sentence definition of the term “tectonic plate”. 28 14  Learning Objectives Reflection Activity How confident are you that you can successfully complete the learning objectives? I can explain the source of internal heat that drives plate tectonic processes I can’t I can do I can do I can do do this some of this most of this all of this I can describe the principal characteristics of Earth’s compositional layers I can’t I can do I can do I can do do this some of this most of this all of this I can identify the distributions of the principal features of Earth’s surface I can’t I can do I can do I can do do this some of this most of this all of this I can write a description of a “tectonic plate”. I can’t I can do I can do I can do do this some of this most of this all of this Complete Learning Journal #3 before examining material that follows. Review the learning objectives below that relate to the Learning Journal activities and consider how confident you are that you could successfully complete each task. Module 2, Part 2: Learning Journal #3 Learning Objectives I can explain how the age of the ocean floor varies relative to the position of the oceanic ridge I can describe how and why sediment thickness varies on the ocean floor I can predict how the ages of volcanoes associated with a hot spot will change relative to the hot spot location I can identify the principal characteristics of hot spots 30 15  Learning Journal Review Assessment 2 Myrs N The figure shows the relative ages 4 Myrs of a chain of volcanoes on the 6 Myrs ocean floor. The volcanoes formed 9 Myrs above a hot spot. What direction has the oceanic plate been moving for the last 9 million years? A. Southeast B. Northwest 31 Review the learning objectives below that relate to the material to be discussed in the slides that follow. Your should be able to successfully complete these tasks when you have finished reviewing the related course resources (e.g., slides, videos, maps). Module 2, Part 2: Course Learning Objectives I can use the locations of earthquakes and volcanoes to draw the approximate locations of the plate boundaries on a world map I can name and label the major plates I can write a definition of the term “plate tectonics” I can describe the relative motions of tectonic plates on either side of the three types of plate boundaries I can identify the characteristics of a divergent plate boundary I can describe how ocean basins form and grow 32 16 LO: I can use the locations of earthquakes and volcanoes to draw the approximate locations of the plate boundaries on a world map Interpret the distribution of earthquakes and volcanoes to predict the locations of the major plate boundaries Sketch the predicted plate boundary locations on one of the blank maps available on the class Moodle site 33 LO: I can use the locations of earthquakes and volcanoes to draw the approximate locations of the plate boundaries on a world map Sketch the predicted plate boundary locations on one of the blank maps available on the class Moodle site 34 17 LO: I can name and label the major plates Label and name the plates Go to the top of the class if you can successfully identify at least four plate boundaries are oceanic ridges and four that are oceanic trenches 35 LO: I can use the locations of earthquakes and volcanoes to draw the approximate locations of the plate boundaries on a world map AND I can name and label the major plates Interpret the distribution of earthquakes and volcanoes to predict the locations of the major plate boundaries North Eurasian American Pacific African Pacific South American Indian- Nazca Australian Antarctica Smaller plates: Cocos Caribbean Philippine Arabian Scotia 36 18 LO: I can describe the relative motions of tectonic plates on either side of the three types of plate boundaries Plates of lithosphere... Move apart: at a Move toward each other: divergent boundary at a convergent boundary Move horizontally What directions of past one another: motion occur at: at a transform oceanic ridges boundary oceanic trenches? 37 LO: I can write a definition of the term “plate tectonics” Define Key Terms Write a short paragraph (15-30 words) that explains the concept of plate tectonics. 38 19 LO: I can identify the characteristics of a divergent plate boundary Oceanic Divergent Boundaries Oceanic plates move apart at oceanic ridges Forms new (seafloor spreading) oceanic lithosphere Oceanic ridges are located far from the margins of ocean basins Mid-Atlantic Where is the Ridge oldest seafloor in this image? 39 LO: I can describe how ocean basins form and grow Observe what happens when continents break apart Initial uplift of continental crust from rising mantle Rifting Stretching and faulting form steep-sided rift valley (Durham is above an old rift) Melting forms magma Can lead to seafloor spreading and new ocean basin Ocean widens with spreading Old ocean basin 40 20 LO: I can describe how ocean basins form and grow From continent to narrow ocean − One continental plate in process of breaking apart (e.g., East Africa) − Red Sea, early stage ocean Thinned crust, volcanoes, rift valley Active volcanoes 41 LO: I can describe how ocean basins form and grow Active volcanoes Tearing a continent apart – initial rifting activity in East Africa today 42 Earth cracking up 21 LO: I can identify the characteristics of a divergent plate boundary Read the partial or complete sentence.. circle the appropriate term. below and... Divergent plate boundaries are typically ridges trenches characterized by oceanic Earthquakes are associated with divergent plate True False boundaries Most active volcanoes are found along divergent True False plate boundaries What is the source of magma that forms at Melting of Melting of oceanic ridges? lithosphere asthenosphere Divergent plate boundaries initially form by Old, cold oceanic Continental breaking apart lithosphere lithosphere Raleigh is moving _________ a divergent away from toward boundary in the Atlantic Ocean How many plates are associated with a typical one two divergent plate boundary Oceanic ridges are found In all ocean Only in the basins Atlantic and Pacific oceans 43 LO: I can identify the characteristics of a divergent plate boundary Which of the locations on the map represent examples of divergent plate boundaries? 44 22  Learning Objectives Reflection Activity How confident are you that you can successfully complete the learning objectives? I can use the locations of earthquakes and volcanoes to draw the approximate locations of the plate boundaries on a world map I can’t I can do I can do I can do do this some of this most of this all of this I can name and label the major plates I can’t I can do I can do I can do do this some of this most of this all of this I can write a definition of the term “plate tectonics” I can’t I can do I can do I can do do this some of this most of this all of this I can describe the relative motions of tectonic plates on either side of the three types of plate boundaries I can’t I can do I can do I can do do this some of this most of this all of this I can identify the characteristics of a divergent plate boundary I can’t I can do I can do I can do do this some of this most of this all of this I can describe how ocean basins form and grow I can’t I can do I can do I can do do this some of this most of this all of this Complete Learning Journal #4 before examining material that follows. Review the learning objectives below that relate to the Learning Journal activities and consider how confident you are that you could successfully complete each task. Module 2, Part 3: Learning Journal #4 Learning Objectives I can describe the processes that occur at oceanic ridges I can describe the characteristic features of the ocean floor, including the ridge, trench, abyssal plain, continental shelf, and island arc I can explain the difference between active and passive continental margins I can predict how sediment thickness and the age of the ocean floor would vary 46 23 Review the learning objectives below that relate to the material to be discussed in the slides that follow. Your should be able to successfully complete these tasks when you have finished reviewing the related course resources (e.g., slides, videos, maps). Module 2, Part 3: Course Learning Objectives I can compare and contrast the three types of convergent plate boundary I can describe the geologic processes that characterize the three major types of convergent plate boundary 47 Learning Journal Review Assessment Identify the features of the ocean floor located at each of the lettered locations. C A B D 48 24 LO: I can compare and contrast the three types of convergent plate boundary Plates of lithosphere... Move apart: divergent Move toward each other: at boundary convergent boundary, 3 types Move horizontally past one another: transform boundary 49 LO: I can compare and contrast the three types of convergent plate boundary The distribution of earthquakes helps predict the locations of the major plate boundaries (ridges & trenches) The distribution of active volcanoes generally indicate the locations of trenches adjacent to convergent 50 boundaries 25 LO: I can compare and contrast the three types of convergent plate boundary Observe the distribution of volcanoes around the Pacific Ring of Fire What do you think could explain the overall pattern? Pacific & Nazca plates are consumed below trenches, generating volcanoes, W E earthquakes, mountain building. 51 LO: I can compare and contrast the three types of convergent plate boundary Identify the three locations on the map that are characterized by oceanic trenches. 52 26 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Ocean/Ocean and Ocean/Continent Convergence Volcanic arc on land, and Eruptions at volcanoes compression forms mountains on island arc formed on plate above subduction zone by rising magma oceanic trench ridge trench One plate moves down into mantle Mantle in over-riding plate Process = subduction melted to form magma Feature = subduction zone Ocean-ocean convergent boundary Ocean-Continent convergent boundary 53 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Predict how this plate configuration will change over time. How would it look different 20 Million Years from now? 54 27 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Continent-Continent Convergence Continent 1 Continent 2 Collision is preceded by the subduction of oceanic lithosphere that brings Pieces of crust continents closer sliced off Thickest crust (70 km), high elevation Continents collide along suture zone 55 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Identify the different types of convergent plate boundaries Label the red lines on the basis of the type of convergent boundary present at that location O-O Ocean-ocean convergent boundary O-C Ocean-continent convergent boundary C-C Continent-continent convergent boundary 56 28 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Compare and contrast ocean-ocean, ocean-continent, and continent-continent convergent boundaries Place a mark in the column to the right if feature is present at convergent boundary type: 1 with no correct answer; 4 with one correct answer Features Ocean- Ocean- Continent- Ocean Continent Continent Trenches currently present Island arc present Mountain belts on overlying plate Volcanoes on plate descending subduction zone Oceanic plate currently descends subduction zone Magma rises through overlying plate Thickest crust on Earth Volcanoes on overlying plate Subduction zone currently present Example: Nazca plate collides with S. America Example: India collided with Eurasia 57 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Which diagram best represents the convergent plate boundary configurations at locations 3, 4, 5, and 8? 58 29 LO: I can describe the geologic processes that characterize the three major types of convergent plate boundary Draw a cross section through the outer layers of Earth along the W-E line Label: Physical features, Geologic processes Indicate the directions of plate motions W E 59 Learning Objectives Reflection Activity How confident are you that you can successfully complete the learning objectives? I can compare and contrast the three types of convergent plate boundary I can’t I can do I can do I can do do this some of this most of this all of this I can describe the geologic processes that characterize the three major types of convergent plate boundary I can’t I can do I can do I can do do this some of this most of this all of this 30 Review the learning objectives below that relate to the material to be discussed in the slides that follow. Your should be able to successfully complete these tasks when you have finished reviewing the related course resources (e.g., slides, videos, maps). Module 2, Part 4: Course Learning Objectives I can discuss the features and relative plate motions associated with a transform plate boundary I can identify the rate of plate motion and explain why some plates move faster than others I can describe how the North American continent was assembled I can describe the concept of terranes and use it to explain the geologic history of North Carolina 61 LO: I can discuss the features and relative plate motions associated with a transform plate boundary Plates of lithosphere... Move apart: divergent Move toward each other: boundary convergent boundary Move horizontally past one another: transform boundary 62 31 LO: I can discuss the features and relative plate motions associated with a transform plate boundary Transform Boundary Observe how these Transform boundary - Plates two plates are moving move horizontally past each other past each other Divergent Divergent boundary – plates move away from each other Transform Analog: Observe how the pieces of pizza can be separated 63 LO: I can discuss the features and relative plate motions associated with a transform plate boundary Transform Boundary Transform boundary - Plates move horizontally past each other Divergent boundary – plates move away from each other Transform boundaries link other 03.07.d1 types of plate boundaries 64 32 LO: I can discuss the features and relative plate motions associated with a transform plate boundary Transform Boundary Observe the pattern of the Mid-Atlantic Ridge Oceanic ridge segment Transform Which parts are the oceanic ridge segments 65 and which parts are transform boundaries? LO: I can discuss the features and relative plate motions associated with a transform plate boundary Transform Boundary Example: San Andreas Fault, CA Links 2 oceanic ridge systems U.S. on 2 plates – North American and Pacific Western California, including Los Angeles, on Pacific plate Moving north  collide with Alaska in many millions of years 66 33 LO: I can discuss the features and relative plate motions associated with a transform plate boundary Apply what you know about plate tectonics to predict which location represents a transform boundary. 1 3 4 2 5 67 LO: I can identify the rate of plate motion and explain why some plates move faster than others Rates of Relative Plate Movement Plates move 1-15 cm/year Some move faster than others 68 But why do some plates move faster than others? 34 LO: I can identify the rate of plate motion and explain why some plates move faster than others What Moves the Plates? Almost all plates have some Ridge push Slab pull – faster plate Other forces, such as motions w/subduction zones convection in mantle 69 How many plates in this image? LO: I can identify the rate of plate motion and explain why some plates move faster than others Rates of Relative Plate Movement Identify 2 plates with ridge push only and 2 with ridge push + slab pull - compare rates of plate motions 70 1. Which ocean are growing or shrinking? 35 LO: I can describe how the North American continent was assembled Supercontinent Cycles NA Distribution of present day continents and oceans 280 Myrs ago: Supercontinent “NA” Pangaea forms; “North America” and “Africa” collide” near equator Appalachian Mountains “NA” 600 Myrs ago: Supercontinent 550 m.y. ago Rodinia, centered over South Pole; breaks up by rifting continental lithosphere 71 600 m.y. ago LO: I can describe how the North American continent was assembled Geologic History of North America Continental shield Continental platform 72 36 LO: I can describe how the North American continent was assembled Geologic ages of North American Crust Brown – stable continental interior, oldest (1-4 Green - Varied billion year old) geology, younger rocks, relatively tectonic terranes unchanged in last added in last 600 600 Myrs Myrs Purple - Older Blue - Relatively rocks deformed by young rocks collisions along overlying thin margins of “old” continental margin continent in last formed when 600 Myrs, smaller Atlantic opened pieces of crust ~200 Myrs ago (tectonic 73 terranes) added LO: I can describe the concept of terranes and use it to explain the geologic history of North Carolina Common settings for the origin of terranes Piece of seafloor Oceanic island or plateau (hot spot) Island arc Micro-continent Must be added (accreted) to continental margin 74 by subduction, collision, or strike-slip faulting 37 LO: I can describe the concept of terranes and use it to explain the geologic history of North Carolina Identifying Tectonic Terranes Major faults or shear Different fossils or zones separate rock chemistry terranes 11.09.a1 Different Different sequence of rocks tectonic settings on either side of for formation of rocks boundary 75 LO: I can describe the concept of terranes and use it to explain the geologic history of North Carolina Terranes and Geology of North Carolina Blue Ridge – (Inner) Piedmont – Carolina Slate Belt – part of ancient terrane, possibly volcanic island arc North America (1.8 microcontinent or terrane (500 Myrs, Byrs old) island arc (~500+Myrs) added ~300 Myrs ago) Charlotte Belt – plutonic igneous Coastal Plain rocks formed from magma along – young convergent boundary Triassic basins – rift basins sedimentary (~300-500 Myrs) formed during opening of rocks over Atlantic Ocean (~200 Myrs) passive margin 76 38 Learning Objectives Reflection Activity How confident are you that you can successfully complete the learning objectives? I can discuss the features and relative plate motions associated with a transform plate boundary I can’t I can do I can do I can do do this some of this most of this all of this I can identify the rate of plate motion and explain why some plates move faster than others I can’t I can do I can do I can do do this some of this most of this all of this I can describe how the North American continent was assembled I can’t I can do I can do I can do do this some of this most of this all of this I can describe the concept of terranes and use it to explain the geologic history of North Carolina. I can’t I can do I can do I can do do this some of this most of this all of this The Changing Solid Earth (and the origin of North Carolina) Notes by David McConnell Department of Marine, Earth and Atmospheric Sciences January 2014 39