A Science Odyssey Mountain Maker, Earth Shaker

Slippin' and a Slidin'

GIF Animation, endless loop: side view of transform boundary

Transform boundaries neither create nor consume crust. Rather, two plates move against each other, building up tension, then releasing the tension in a sudden and often violent jerk. This sudden jerk creates an earthquake.

The San Andreas Fault is undoubtedly the most famous transform boundary in the world. To the west of the fault is the Pacific plate, which is moving northwest. To the east is the North American Plate, which is moving southeast.

Los Angeles, located on the Pacific plate, is now 340 miles south of San Francisco, located on the North American plate. In 16 million years, the plates will have moved so much that Los Angeles will be north of San Francisco!

The Sea Floor Spread (divergent boundary)

The Continental Slide (convergent boundary)

The Continental Crush (collisional boundary)

Back to first page of Plate Tectonics

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