5. seismology and plate tectonicsseismo.snu.ac.kr/class/seismology/swch5.1-5.4v1.1.pdf · 1 5....

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5. Seismology and Plate Tectonics5. Seismology and Plate Tectonics

• Introduction

• Plate kinematics

• Spreading centers

• Subduction zones

• Ocean intraplate earthquakes and tectonics

• Continental earthquakes and tectonics

• Faulting and deformation in the earth

Plate Tectonics Summary (I)Plate Tectonics Summary (I)

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Plate Tectonics Summary (II)Plate Tectonics Summary (II)

Plate Tectonics Summary (III)Plate Tectonics Summary (III)

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Global SeismicityGlobal Seismicity

Deep SeismicityDeep Seismicity

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Seismicity CrossSeismicity Cross--section (Wadatisection (Wadati--Benioff zone)Benioff zone)

Plate kinematics (Euler pole)Plate kinematics (Euler pole)

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Relative Plate Motion and Plate BoundayRelative Plate Motion and Plate Bounday

Angular and Linear Velocity (I)Angular and Linear Velocity (I)

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Angular and Linear Velocity (II)Angular and Linear Velocity (II)

Relative Plate Motions w.r.t North AmericaRelative Plate Motions w.r.t North America

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PacificPacific--North American Plate BoundaryNorth American Plate Boundary

Global Plate CircuitGlobal Plate Circuit

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Relative Plate MotionsRelative Plate Motions

Current and Historic Plate VelocitiesCurrent and Historic Plate Velocities

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Bend at 43 Ma:

Absolute Plate Motions (I)Absolute Plate Motions (I)

Bend at 43 Ma:

Plate direction change?

Mantle wind?

Moving hot spot base?

Absolute Plate Motions (II)Absolute Plate Motions (II)

Plume?

Ri ht R ll?Richter Roll?

Basin and Range extension?

Propagating Rift?

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Earthquakes at an oceanic spreading centerEarthquakes at an oceanic spreading center

Earthquakes on slow spreading centerEarthquakes on slow spreading center

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Earthquakes on fast spreading centerEarthquakes on fast spreading center

Normal Faulting on slow spreading centerNormal Faulting on slow spreading center

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Cooling of the oceanic plate (I)Cooling of the oceanic plate (I)

Cooling of the oceanic plate (II)Cooling of the oceanic plate (II)

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SubductionSubduction zoneszones

Earthquakes at Earthquakes at subductionsubduction zoneszones

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Double Seismic ZoneDouble Seismic Zone

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Normal Faulting at TrenchesNormal Faulting at Trenches