Seismic Wave Behavior: Critically Refracted Rays Ping Arrivals

How does the ping sound announce refracted rays?

Multiple seismic paths migrate downward to be critically refracted off of increasingly higher-velocity boundaries showing that although the deepest path is the longest, the transit time is less than the direct wave that travels entirely in the slow layer. AUDIO ARRIVAL SOUNDS.

Total Time: 33s
Level: Intermediate

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Like other waves, seismic waves obey the laws of physics. In this activity Physics students have the opportunity to apply their understanding of the basic concepts of waves (e.g. reflection, refraction and transmission of energy) as they examine seismic data to determine how far it is from the surface to the bedrock.

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