The Moving Earth:

A poem of tectonic proportions

Welcome to Earth, glad you are here!

Let’s look inside at its layers by taking a peer;

The first three: litho-, astheno- and meso- sphere

Are what causes changes to the land and sea-floor

And then we get a magnetic field from the inner and outer core.

But why should I keep this knowledge stored?

Remember convection currents;

Hot magma moving in torrents?

The magma rises because the gases give lift,

Then the plates spread apart in “continental drift”.

As the plates travel because of the moving heat

There are three ways that these plates may meet:

Plates may converge, we say they collide,

Plates may diverge, we say they divide,

Plates may transform, it’s where they slide.

At these boundaries are many changes,

It is here that the planets land rearranges.

Like where plates converge and collide

Features form at the boundaries at the end of their ride.

If the collision is continental-continental

Mountains are built in a way not-so-gentle;

And when the collision is continental-oceanic,

Volcanoes arise and create quite a panic;

Yet, when oceanic-oceanic come, one plate will sink,

Forming volcano island arcs at the boundary’s brink.

Subduction occurs with the last two examples:

Subduction is when one plate ducks under into the mantle.

Then you have divergent boundaries and plates divide,

Like at mid-ocean ridges, where oceans grow wide.

The best-known mid-ocean ridge is the mid-Atlantic

Which is growing by sea-floor spreading and becoming gigantic.

What is sea-floor spreading, umm the spreading of a sea-floor,

Earth science terms mean what they say, no less, no more.

Transform boundaries occur between plates

Allowing sliding plates to cause earthquakes.

Because of these changes in the earth’s crust

We see the land as it starts to shake and bust.

Mostly the bursts are volcanic, along the ring of fire

Where magma rises up and gets pushed higher and higher,

So high in fact it is released from mountaintops

That volcanoes appear where the earth pops.

This ring of fire is able to function,

Because magma forms after plate subduction.

Subduction occurs because the plates (o-c) converge

And when the oceanic plate melts, the magma will surge.

There are also volcanoes found on hot spots;

This is where magma rises because a spot is hot.

Magma is underground rock that is molten

Lava is the rock when it left the earth by an opening.

Because we looked at volcanoes first,

We should at the quaking of the earth.

We know that when the earthquakes

Waves of energy cause the crust to break.

These seismic waves are of various types,

Primary, Secondary, and surface waves cause all the hype.

Primary waves are the first and the fastest,

But they do not cause damage that is massive.

Most damage comes from rolling surface waves

The ground actually rolls in slinky-like ways.

But as we return to the Primary,

They move through solids and liquids in a hurry.

Then the secondary waves, also known as S,

(which only move in solids) add to the wavy mess.

When we look at both S & P waves to take our measures,

We find where the earthquake was buried underground, like pirate treasure.

We find the focus: that is the point deep down,

By looking at the epicenter, the point above ground.