Loading in 2 Seconds...
Loading in 2 Seconds...
http://plateboundary.rice.edu/ 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 • Use descriptive terms: 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 Theory • 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 Crust - 2 Mantle Core Physical / Mechanical Lithosphere Asthenosphere Mesosphere
3 Basic Boundary Interactions 5 Basic Boundary Types
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? Peru-Chile Trench Andes Mountains Nazca Plate South American 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?
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? Tibetan Plateau Himalayan Mountains Eurasian Plate Indian-Australian 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?
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
What skills did you use in undertaking this activity? • Historical use … • How might you use it in your classroom? • What might you modify?