Transcript Slow Motion Earth

Slow Motion Earth
• How do we know slow
objects are moving?
• Plates
– Broken pieces of
Earth’s crust
• Theory of Plate
Tectonics
– Earth’s plates move
ever so slowly in all
directions
Calculating Distance
• If the pacific plate moves 5 cm a year,
how far will it move in 1,000 years?
– 5 cm x 1000 yr = 5000 cm which is 50 m
• What would this convert to per day?
– 5 cm ÷ 365 days = .0137 cm/day
Predicting
• Los Angeles is on the Pacific Plate moving
northwest. San Francisco is on the North
American Plate moving southeast. These 2
cities are moving toward each other at 5
cm/yr. If the two cities are 554,000 m apart,
how long will it take the two cities to meet?
• 554,000 m x 100 cm/m = 55,400,000 cm
• Time = 55,400,000 ÷ 5cm/yr =
• 11,080,000 years