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http://www.geophysics.rice.edu/plateboundary/ Where are the Earth’s tectonic plates and their boundaries? What happens at plate boundaries? How do Earth scientists classify plate boundaries?. Part 1.
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http://www.geophysics.rice.edu/plateboundary/ Where are the Earth’s tectonic plates and their boundaries? What happens at plate boundaries? How do Earth scientists classify plate boundaries?
Part 1. • Identify the patterns of your area of expertise – volcanology, seismology, geography, geochronology - AT PLATE BOUNDARIES • Describe what you observe – do not interpret what you see, just describe the patterns • Wide or narrow, straight or curved, symmetric or not symmetric, deep or shallow, ridge or valley, active or inactive • Identify 3-5 boundary types; color each on your transparency; define in words
Part 2. • Bring together areas of expertise – volcanology, seismology, geography, geochronology • Correlate your data sets; what collective patterns emerge? • Identify 3-5 boundary types; color each on a master transparency; define in words
Part 3. • Describe the different types of boundaries • What patterns were related in the different data sets?
Plate Tectonics • The upper mechanical layer of Earth (lithosphere) is divided into rigid plates that move away, toward, and along each other • Most (!) geologic action occurs at plate boundaries in DISTINCT patterns
Compositional Physical / Mechanical
1. Divergent Boundaries • Volcanic activity in fissures, some volcanos • Shallow earthquakes, on plate boundary • Young crust, symmetrical around boundary • Ridge • Rocks? Mid- Atlantic Ridge North American Plate Eurasian Plate
Nazca Plate South American Plate Antarctic Plate
2. Convergent Boundaries (a) Ocean-continent convergence • Volcanos tight, parallel boundary, landward • Shallow to deep earthquakes • Age varies on one side of the boundary; not symmetrical • Trench, mountain chain • Rocks? Andes Mountains Peru-Chile Trench South American Plate Nazca Plate
2. Convergent Boundaries (b) Ocean-ocean convergence • Volcanos tightly spaced, parallel boundary, arc • Shallow to deep earthquakes • Age varies on one side of the boundary; not symmetrical • Trench, volcanic island chain • Rocks? Mariana Islands Marianas Trench Philippine Plate Pacific Plate
Eurasian Plate Indian Plate
Tibetan Plateau Mt. Everest Himalayan Mtns.
2. Convergent Boundaries (c) Continent-continent convergence • Volcanos rare, dispersed • Shallow (to medium) dispersed earthquakes • No age data • High mountain chain • Rocks? Himalayan Mountains Tibetan Plateau Indian-Australian Plate Eurasian Plate
3. Transform-Fault Boundaries • Volcanos dispersed, most on one side • Earthquakes complex, shallow (to medium) on both sides • Age data not symmetrical, one side of boundary • Complex topography, wide mountains and basins • Rocks? Pacific Plate North American Plate
Plate Tectonics • The upper mechanical layer of Earth (lithosphere) is divided into rigid plates that move away, toward, and along each other • Most (!) geologic action occurs at plate boundaries in DISTINCT patterns
It’s all about convection and heat (loss)! Vigorous convection drives plate tectonics
And for the rest of the week … • What features do you expect to see on other planets if plate tectonics processes are active? • What does this tell you about the interior of the planet?
What skills did you use in undertaking this activity? • Historical use … • How might you use it in your classroom? • What might you modify?