Educational game

Earthquake Epicenter Finder

P-waves · S-waves · triangulation · epicenter

Learning outcomeUse three seismic stations to triangulate an earthquake epicenter.

Learning challenge

Station A S−P gap25 sStation B S−P gap38 sStation C S−P gap52 s

Station A radius210 km

Station B radius319 km

Station C radius437 km

Learning focus

Convert S–P arrival gaps to distance circles and use three stations to constrain the epicenter.

distance ≈ Δt / (1/vS − 1/vP)