Nonlinear Surface Wave Propagation and Attenuation from an Array of Cylindrical Cavity Sources

Indianapolis, IN

This project further developed an existing program that models nonlinear wave propagation near the Earth's surface. Before this project, the program was capable of modeling data from two cylindrical sources of energy, and my task for the summer was to expand this program to be able to handle input from ten sources. Ultimately, this project seeks to form a comparison between linear and nonlinear wave propagation from an array of sources in order to create a rule for source array spacing with attenuation of coherent wave noise when nonlinear wave propagation dominates, as it does in soft materials such as soils and sand. In general, linear propagation is assumed in array design, but under many conditions this leads to significant error, as the behavior is often truly nonlinear. Improvements in array design in nonlinear material can lead to significant improvements in signal to noise ratio of recorded seismic data in the exploration for oil and gas. Also, this work can be scaled up in amplitude to better understand earthquake seismic wave propagation in soft sediments.