PLATE TECTONICS Alfred Wegener 1880 1930 Alfred Wegener

PLATE TECTONICS

Alfred Wegener (1880 -1930)

Alfred Wegener (1880 -1930) The Origin of Continents and Oceans (1915)

I. Continental Drift

Pangea: “all lands”

I. Continental Drift A. Fit of the Continents

Fit of the Continents

I. Continental Drift A. Fit of the Continents B. Fossil Evidence

I. Continental Drift A. Fit of the Continents B. Fossil Evidence C. Rock Types

I. Continental Drift A. Fit of the Continents B. Fossil Evidence C. Rock Types D. Paleoclimate Evidence

PLATE TECTONICS I. Continental Drift Alfred Wegner (1915) A. Fit of the Continents B. Fossil Evidence C. Rock Types D. Paleoclimate Evidence WHAT IS MISSING………?

II. Mounting Evidence of Contin. Drift

A. Earth’s magnetic field

A. Earth’s magnetic field

B. Polar Wandering (S. K. Runcorn, 1950)

II. Mounting Evidence of Contin. Drift A. Earth’s magnetic field B. Polar Wandering (S. K. Runcorn, 1950) C. Sea Floor Spreading (Harry Hess, 1960)

Sea floor spreading

II. Mounting Evidence of Contin. Drift A. Earth’s magnetic field B. Polar Wandering (S. K. Runcorn, 1950) C. Sea Floor Spreading (Harry Hess, 1960) D. Geomagnetic Reversals

Geomagnetic Reversals

video

III. Plate Tectonics

III. Plate Tectonics A. Concept: an assimilation of the ideas of Wegner (continental drift) with sea floor spreading and geomagnetics Tuzo Wilson

III. Plate Tectonics A. Concept: an assimilation of the ideas of Wegner (continental drift) with sea floor spreading and geomagnetics B. Plate Boundaries

The Wilson Cycle

III. Plate Tectonics A. Plate Boundaries 1. Divergent Hot Spot and Triple Junctions

A divergent boundary…. .

A divergent boundary…. . animation

A modern-day divergent boundary…. .

A. Plate Boundaries 2. Convergent Subduction Zone

III. Plate Tectonics A. Plate Boundaries 1. Divergent 2. Convergent a. oceanic-oceanic

Converging boundary…. . Oceanic-Oceanic animation

Converging boundary…. .

III. Plate Tectonics A. Plate Boundaries 1. Divergent 2. Convergent a. oceanic-oceanic b. oceanic-continental

Converging boundary…. . Continental-Oceanic animation

Converging boundary…. .

III. Plate Tectonics A. Plate Boundaries 1. Divergent 2. Convergent a. oceanic-oceanic b. oceanic-continental c. continental-continental

Converging boundary…. . Continental-Continental animation

III. Plate Tectonics A. Plate Boundaries 1. Divergent 2. Convergent a. oceanic-oceanic b. oceanic-continental c. continental-continental 3. Transform

Transform boundary…. .

Transform boundary…. . animation

III. Plate Tectonics A. Plate Boundaries 1. Divergent 2. Convergent a. oceanic-oceanic b. oceanic-continental c. continental-continental 3. Transform 4. Other (hotspots)

Hot Spots…. . animation