Light Refraction Analogy for Seismic Shadow Zones

We propose analogy modeling of seismic wave refraction using light refraction to enhance the understanding of P-wave and S-wave shadow zone formation. In the first experiment, we simulate an earthquake within a fishbowl using a point light source, where the water represents the Earth's mantle and a glass ball represents the outer core, demonstrating observable shadow bands on the opposite side. The second experiment introduces a simplified 2D method for observing shadow zones using a transparent cylindrical beaker and a water tank. In the third experiment, we measure shadow zones in a plane using computer simulations. By analyzing the data obtained through angle measurements, we calculate the refractive index. These experiments not only aid in comprehending the historical development of knowledge regarding seismic waves and Earth's internal structures but also provide valuable educational insights for teaching physics and earth science, despite the inherent limitations of the educational model.