Layers of the Earth—What is the Moho? Open

9min 20s Novice Spanish Spanish

How was it discovered?

Without understanding what it is, we often hear the phrase “down to the Moho”, meaning very very deep. The Mohorovicic Discontinuity, commonly called the “Moho” is recognized as the boundary zone between Earth's crust and the mantle.

This boundary marks a change in seismic-wave velocity from the crust to the uppermost mantle within the (lithospheric) plate. This boundary was discovered by Andrija Mohorovičić, a Croatian meteorologist-turned seismologist, after an earthquake in Croatia in 1909.

This animation discusses the history of the discovery as well as the logic behind it.
Spoiler Alert: It is about Snell’s Law.

CLOSED CAPTIONING: .srt file is included with the downloiad. Use appropriate media player to utilize captioning.

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