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 BoundariesWhere Stuff Happens

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

CompositionalCrust - 2MantleCore

Physical / MechanicalLithosphere

AsthenosphereMesosphere

3 Basic Boundary Interactions

5 Basic Boundary Types

1. Divergent Boundaries

Mid-AtlanticRidge

North AmericanPlate Eurasian

Plate

• Volcanic activity in fissures, some volcanos• Shallow earthquakes, on plate boundary• Young crust, symmetrical around boundary• Ridge• Rocks?

South American Plate

Nazca Plate

Antarctic Plate

Andes Mountains

2. Convergent Boundaries(a) Ocean-continent convergence

Nazca Plate

AndesMountains

South American Plate

Peru-Chile Trench

• Volcanos tight, parallel boundary, landward• Shallow to deep earthquakes• Age varies on one side of the boundary; not symmetrical• Trench, mountain chain• Rocks?

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

Himalaya Mountains

Tibetan Plateau

Himalayan Mtns.

Mt. Everest

2. Convergent Boundaries(c) Continent-continent convergence

TibetanPlateau

Indian-Australian Plate

EurasianPlate

HimalayanMountains

• Volcanos rare, dispersed• Shallow (to medium) dispersed earthquakes• No age data• High mountain chain• Rocks?

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

What’s Driving Plate Tectonics

on Earth?

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?