Towards automatically building starting models for full-waveform inversion using global optimization methods: A PSO approach via DEAP+ Devito

Abstract

In this work, we illustrate an example in estimating the macromodel of velocities in the subsurface through the use of global optimization methods (GOMs). The optimization problem is solved using DEAP (Distributed Evolutionary Algorithms in Python) and Devito, Python frameworks for evolutionary and automated finite difference computations, respectively. We implement a Particle swarm optimization (PSO) with an “elitism strategy” on top of DEAP, leveraging its transparent, simple and coherent environment for implementing of evolutionary algorithms (EAs). The high computational effort, due to the huge number of cost function evaluations (each one demanding a foward modeling step) required by PSO, is alleviated through the use of Devito. The combined use of both frameworks yields not only an efficient way of providing acoustic macro models of the P-wave velocity field (Vp), but also significantly reduces the amount of geophysicist effort in fulfilling this task.

Oscar Mojica

Geologist & Geophysicist/Researcher

My research interests include parallel programming and optimization of scientific applications.