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Explore geophysical field trip and tutorials at Malham Tarn (North Yorkshire) in October 2009, focusing on refraction analysis by Sebastian Rost from the University of Leeds. Learn about traveltime curves, peaceful nuclear explosions, seismic wavefield, raypaths, and more.
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SOEE2102 – Geophysical Field Trip and Tutorials Malham Tarn (North Yorkshire) October 2009 Refraction Analysis Sebastian Rost University of Leeds 2009
At criticaldistance: r = 90 ic = critical angle
Seismic Wavefield and Seismic Raypaths Courtesy of M. Thorne (Univ. Utah)
x Traveltimes Direct wave: (from velocity = distance / time )
Refracted Wave: Snell’s Law
Different ways to express the refracted traveltime curve Intercept time
Crossover distance: Tdirect = Trefracted Xcross > 2z
Intercept Times q1c q1 q2
General multi-layer formula Layer thickness: z Layer velocity: V
Up-Dip Q Down-Dip Q
Combining Up-Dip and Down-Dip shoots with and Vd and Vu are apparent velocities!
Shot point geometries 12 element geophone spread Possible shot point locations