Earthquakes shake united state up, however they’re as herbal as rain. They’ve increased up Northwest hills over millions and millions of years. What causes earthquakes? It’s the consistent motion of the earth’s crust.

Earthquakes room Inevitable

Earthquakes are the result of the structure of our planet. The planet beneath united state is rock all the means through, but only the thin crust is a brittle solid. Within the earth, the absent is for this reason softened by warmth that it gradually moves and flows.

The earth is favor an egg

The within of the earth is layered something favor an egg. Both have a thin, brittle shell. The tardy of the earth is broken into pieces, favor the cracked covering of a hardboiled egg. The mantle the the earth is favor the egg white, and the core of the earth lies in the center, like the egg yolk.


Not together solid together it seems The earth’s brittle late is damaged into pieces that geologists speak to plates.

These plates room in continuous slow motion, brought by currents in the earth’s heat-softened interior. This convection currents move at around the rate that our fingernails grow.

What space convection currents? If you’ve ever watched a lava lamp, you’ve watched convection currents at work.

warm (from the light bulb) warms up a colored liquid at the basic of the lamp. The colored fluid rises, because hot liquids are less dense than cool ones. as the blobs of warm liquid relocate away indigenous the warm source, castle cool off, become an ext dense again, and also sink back to the bottom. This bicycle of motion is referred to as a convection current.

Heat keeps plates in motion

The earth is something favor a lava lamp. Inside the mantle, convection currents increase slowly, fueled by warmth in the earth’s core. Most of the earth’s warmth is left end from the large Bang at the formation of the Universe. Continuous radioactive degeneration constantly produces an ext heat.

The convection currents in ~ the planet are huge. They carry the tardy plates in addition to them, since the crust is so slim in comparison.

Convection currents circulate gradually within the earth’s mantle.

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Plate activity makes earthquakes all the key that comprise the crust space jostling against each other. Strain builds up together these key of solid absent grind together. Eventually the rocks can’t take it any more. The key slip and also the built-up stress is all of sudden released together an...Earthquake! since of the jostling of the plates, earthquakes usually happen at plate edges.

Motion is at the margin The Pacific Northwest lies on the margin of the north American continental plate. Simply off the coast, a thick oceanic bowl is sliding—subducting—beneath us. This plate movements are continuous, and so earthquakes space inevitable.

The earth has bowl Earth’s late is written of eight big plates and also a variety of small ones.

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Strings that triangles and lines show the edges of crustal plates.
YOU ARE here detail: in ~ the sheet of the Pacific Northwest, an oceanic plate is slide (subducting) in ~ a continental plate.

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