Review for Exam 32 & 33 By Mrs. Senger The speed of a seismic wave depends on The type of material it travels through The amplitude Its frequency The amount of sediment The speed of a seismic wave depends on The type of material it travels through The amplitude Its frequency The amount of sediment Motion in a P Wave is Side to side Up and down Transverse Longitudinal Motion in a P Wave is Side to side Up and down Transverse Longitudinal The fastest seismic wave is a Rayleigh wave Tertiary wave Secondary wave Primary wave The fastest seismic wave is a Rayleigh wave Tertiary wave Secondary wave Primary wave A seismograph Helps prevent earthquakes Measures ground movement Predicts earthquakes Measures fault displacement A seismograph Helps prevent earthquakes Measures ground movement Predicts earthquakes Measures fault displacement Secondary waves can travel through all areas of the Earth except the Mantle Surface Inner core Outer core Secondary waves can travel through all areas of the Earth except the Mantle Surface Inner core Outer core The outer core Is solid as a rock Transmits S waves Has a plastic like flow Flows fast enough to power the Earth’s magnetic field The outer core Is solid as a rock Transmits S waves Has a plastic like flow Flows fast enough to power the Earth’s magnetic field The Earth’s layer with plastic like behavior is the Mantle Inner core Outer core Crust The Earth’s layer with plastic like behavior is the Mantle Inner core Outer core Crust The core of the earth is probably composed of An iron-nickel alloy Aluminum oxides Silicate minerals Calcium magnesium sulfate The core of the earth is probably composed of An iron-nickel alloy Aluminum oxides Silicate minerals Calcium magnesium sulfate Evidence to support the concept that the inner core is solid & the outer core is liquid comes from The inner core is not solid, it is a liquid Refraction of seismic waves as they encounter different mediums The absence of waves after the crust The wave shadow effect of P & S waves and the P waves increasing speed as it enters the core Evidence to support the concept that the inner core is solid & the outer core is liquid comes from The inner core is not solid, it is a liquid Refraction of seismic waves as they encounter different mediums The absence of waves after the crust The wave shadow effect of P & S waves and the P waves increasing speed as it enters the core The inner core is solid because It is composed of iron and nickel The surrounding outer layers act as a blanket to insulate the core Pressure from the weight of the surrounding layers prevents the inner core from melting None of these, the inner core is a liquid The inner core is solid because It is composed of iron and nickel The surrounding outer layers act as a blanket to insulate the core Pressure from the weight of the surrounding layers prevents the inner core from melting None of these, the inner core is a liquid The outer core is a liquid because It is magnetically charged Of less weight, and thus less pressure The inner core is solid It is composed of molten iron The outer core is a liquid because It is magnetically charged Of less weight, and thus less pressure The inner core is solid It is composed of molten iron The outer core is thought to be molten because it Is denser than the inner core Will not transmit S waves Will not transmit P waves Is made of iron and nickel The outer core is thought to be molten because it Is denser than the inner core Will not transmit S waves Will not transmit P waves Is made of iron and nickel The earth’s magnetic field is generated in The outer core The mantle The crust Space The earth’s magnetic field is generated in The outer core The mantle The crust Space The mantle is composed of Iron and nickel Solid rock Half liquid and half rocky material Iron-rich silicate rocks The mantle is composed of Iron and nickel Solid rock Half liquid and half rocky material Iron-rich silicate rocks The upper mantle is the region known as the Centrosphere Mohorovicic Lithosphere Asthenosphere The upper mantle is the region known as the Centrosphere Mohorovicic Lithosphere Asthenosphere Thermal convection movement in the upper mantle Generates electric current that powers the magnetic fields Heats the earth’s core by friction Is usually negligible Greatly influences the Earth’s surface features Thermal convection movement in the upper mantle Generates electric current that powers the magnetic fields Heats the earth’s core by friction Is usually negligible Greatly influences the Earth’s surface features The crustal surface and the uppermost section of the mantle is called the Mohorovicic Centrosphere Asthenosphere Lithosphere The crustal surface and the uppermost section of the mantle is called the Mohorovicic Centrosphere Asthenosphere Lithosphere The lithosphere floats atop of the Mohorovicic Asthenosphere Crust mantle The lithosphere floats atop of the Mohorovicic Asthenosphere Crust mantle Movement of the lithosphere Has leisurely pace and allows the formation of gentle rolling hills Causes earthquakes and volcanoes Has a plastic like flow None of these Movement of the lithosphere Has leisurely pace and allows the formation of gentle rolling hills Causes earthquakes and volcanoes Has a plastic like flow None of these What portion of the surface crust is dense and thin? Ocean crust Continental crust Both Neither What portion of the surface crust is dense and thin? Ocean crust Continental crust Both Neither What portion of the surface crust is thick and low density? Ocean crust Continental crust Both Neither What portion of the surface crust is thick and low density? Ocean crust Continental crust Both Neither Continental crust is very buoyant compared with ocean crust because the continental crust is Thinner than ocean crust Very young and fresh Mostly granitic rocks where ocean is mostly basaltic Mostly basaltic with bubbles from the lava flow Continental crust is very buoyant compared with ocean crust because the continental crust is Thinner than ocean crust Very young and fresh Mostly granitic rocks where ocean is mostly basaltic Mostly basaltic with bubbles from the lava flow In an undisturbed sample of rocks, the youngest rocks are found At the bottom At the top As an eroded bed In the core of the anticline In an undisturbed sample of rocks, the youngest rocks are found At the bottom At the top As an eroded bed In the core of the anticline The San Andreas fault in California is a Thrust fault Normal fault Strike slip fault Syncline The San Andreas fault in California is a Thrust fault Normal fault Strike slip fault Syncline When rock is subject to compressive force, it may fault. If the rocks in the hanging wall are pushed up over the rocks of the footwall, it is called Reverse Normal Strike slip Syncline When rock is subject to compressive force, it may fault. If the rocks in the hanging wall are pushed up over the rocks of the footwall, it is called Reverse Normal Strike slip Syncline A fault in which the footwall has moved down relative to the hanging wall is called a Reverse Normal Strike slip Syncline A fault in which the footwall has moved down relative to the hanging wall is called a Reverse Normal Strike slip Syncline The Richter scale measures an earthquake’s Damage Magnitude Frequency All of these The Richter scale measures an earthquake’s Damage Magnitude Frequency All of these Plates that are moving away from each other are called Convergent Divergent Normal Strike slip Plates that are moving away from each other are called Convergent Divergent Normal Strike slip Plates that are moving towards each other are called Convergent Divergent Normal Strike slip Plates that are moving towards each other are called Convergent Divergent Normal Strike slip When continental crust and ocean crust converge, which plate dives below? Continental Oceanic Neither Both melt at the surface When continental crust and ocean crust converge, which plate dives below? Continental Oceanic Neither Both melt at the surface What is the area where the oceanic plate melts beneath the surface at a convergent boundary? Subduction zone Rift valley Trench None of these What is the area where the oceanic plate melts beneath the surface at a convergent boundary? Subduction zone Rift valley Trench None of these Where would you find an ocean trench? Strike slip boundary Divergent boundary Convergent boundary All of these Where would you find an ocean trench? Strike slip boundary Divergent boundary Convergent boundary All of these Where would you find a rift valley? Strike slip boundary Divergent boundary Convergent boundary All of these Where would you find a rift valley? Strike slip boundary Divergent boundary Convergent boundary All of these Wegener’s theory of continental drift Was not accepted in the early 1900’s Was first considered a break through Received a Nobel prize Proposed that Continental Drift was generated by convection motion Wegener’s theory of continental drift Was not accepted in the early 1900’s Was first considered a break through Received a Nobel prize Proposed that Continental Drift was generated by convection motion Alfred Wegener supported his theory of continental drift by all of these EXCEPT Using paleoclimatic data (glaciers) Fitting together shorelines like a puzzle Making connections between rocks, structures, plants, fossils etc from Africa and South America Paleomagnetic data Alfred Wegener supported his theory of continental drift by all of these EXCEPT Using paleoclimatic data (glaciers) Fitting together shorelines like a puzzle Making connections between rocks, structures, plants, fossils etc from Africa and South America Paleomagnetic data The Earth’s magnetic record is recorded By rocks at the North and South poles In minerals that align themselves with the Earth’s magnetic poles By certain igneous minerals in rocks None of these The Earth’s magnetic record is recorded By rocks at the North and South poles In minerals that align themselves with the Earth’s magnetic field By certain igneous minerals in rocks None of these The theory of seafloor spreading is supported by Geological, biological, and climatic data The change in the Earth’s polarity Paleomagnetic analysis of the ocean’s floor None of these The theory of seafloor spreading is supported by Geological, biological, and climatic data The change in the Earth’s polarity Paleomagnetic analysis of the ocean’s floor None of these Magnetic surveys of ocean floors reveal That reversed polarity is rare Thin oceanic crust composed of basaltic rocks Alternating strips of normal and reversed polarity paralleling the midAtlantic Ridge All of these Magnetic surveys of ocean floors reveal That reversed polarity is rare Thin oceanic crust composed of basaltic rocks Alternating strips of normal and reversed polarity paralleling the midAtlantic Ridge All of these The Earth’s magnetic field Never changes Has reversed itself many times Is centered at the Earth’s core Both the second and third answer The Earth’s magnetic field Never changes Has reversed itself many times Is centered at the Earth’s core Both the second and third answer According to the theory of seafloor spreading, molten rock is rising up along The mid-ocean ridges Surrounding the Pacific volcanic rim Trenches that border continental margins None of these According to the theory of seafloor spreading, molten rock is rising up along The mid-ocean ridges Surrounding the Pacific volcanic rim Trenches that border continental margins None of these The ocean crust Becomes older away from the midocean ridges Becomes younger away from the mid-ocean ridges Is the same age worldwide Ranges in age depending on the ocean The ocean crust Becomes older away from the midocean ridges Becomes younger away from the mid-ocean ridges Is the same age worldwide Ranges in age depending on the ocean The theory of plate tectonics states that Buoyant lithospheric plates float on top of the rigid asthenosphere The plates move in conveyor-belt fashion as new crust is generated at the continental margins and destroyed at the mid-ocean ridge The lithosphere is broken up into large palates that move as the result of convection within the asthenosphere Earthquakes & volcanic activity results from convection motion in the lithosphere The theory of plate tectonics states that Buoyant lithospheric plates float on top of the rigid asthenosphere The plates move in conveyor-belt fashion as new crust is generated at the continental margins and destroyed at the mid-ocean ridge The lithosphere is broken up into large plates that move as the result of convection within the asthenosphere Earthquakes & volcanic activity results from convection motion in the lithosphere Most of the Earth’s seismic activity, volcanism, and mountain building occur along Plate boundaries Transform fault boundaries Convergent boundaries Divergent boundaries Most of the Earth’s seismic activity, volcanism, and mountain building occur along Plate boundaries Transform fault boundaries Convergent boundaries Divergent boundaries The oldest rocks are found At convergent boundaries In the ocean basins At divergent boundaries On continental land The oldest rocks are found At convergent boundaries In the ocean basins At divergent boundaries On continental land Divergent boundaries are areas of Crustal formation Continuous, high magnitude earthquakes Crustal destruction Intense compressional forces Divergent boundaries are areas of Crustal formation Continuous, high magnitude earthquakes Crustal destruction Intense compressional forces Spreading centers occur along The northern and western margins of the Juan de Fuca Plate Mid-ocean ridges Transform faults Trenches Spreading centers occur along The northern and western margins of the Juan de Fuca Plate Mid-ocean ridges Transform faults Trenches Convergent boundaries are Regions of great mountain building Areas of plate subduction Regions of plate collision All of these Convergent boundaries are Regions of great mountain building Areas of plate subduction Regions of plate collision All of these Earthquakes in the absence of seafloor spreading, oceanic trenches, or volcanic activity is a characteristic feature of Subduction zone Divergent boundaries between plates Convergent boundaries between plates Transform fault boundaries between plates Earthquakes in the absence of seafloor spreading, oceanic trenches, or volcanic activity is a characteristic feature of Subduction zone Divergent boundaries between plates Convergent boundaries between plates Transform fault boundaries between plates