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You're listening to Shortwave from NPR.

Hi, shortwavers. Sydney Lepkin guest hosting today.

If you were to look out over the New York City skyline,

Antoinna Katwa says you might notice something interesting.

What you see are clusters of skyscrapers all over Manhattan.

Clusters. That's the interesting part. There are

some in midtown, some are downtown, but not in between. As a geologist, Angina says part of the

reason it looks like this has to do with what happened 500 million years ago when New York was

sitting atop an ancient continent called Laurentia.

And opposite side of an ancient ocean was another continent called Gondwana land.

Now over the course of about 150 million years, these two continents gradually moved towards

each other, closing the ocean, and the ocean sediments

beneath were squeezed and pushed upwards, and as these two continents collided, the landscape

was transformed into towering mountains. Over time, these towering mountains were weathered down

until just their bases were left,

underground but near the surface.

And this, Angena says, is where New York skyscrapers are rooted.

And those particular clusters of skyscrapers congregate around hard bedrock known as the Manhattan Schist.

For Angina, rocks contain stories, and those stories explain our world, from the fossil fuel

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