Why is the oldest seafloor less than 180 million years when the oldest continental crust is about 4 billion years old?

since the oldest pecan crust is so much younger than the oldest continental crust, scientists realized that sea floor was being destroyed in a relatively short time.

Explanation:

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

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