<  Back to the Polytechnique Montréal portal

Seismic modeling and inversion using half-precision floating-point numbers

Gabriel Fabien-Ouellet

Article (2020)

[img]
Preview
Published Version
Terms of Use: All rights reserved.
Download (1MB)
Cite this document: Fabien-Ouellet, G. (2020). Seismic modeling and inversion using half-precision floating-point numbers. Geophysics, 85(3), F65-F76. doi:10.1190/geo2018-0760.1
Show abstract Hide abstract

Abstract

New processors are increasingly supporting half-precision floating-point numbers, often with a significant throughput gain over single-precision operations. Seismic modeling, imaging, and inversion could benefit from such an acceleration, but it is not obvious how the accuracy of the solution can be preserved with a very narrow 16-bit representation. By scaling the finite-difference expression of the isotropic elastic wave equation, we have found that a stable solution can be obtained despite the very narrow dynamic range of the half-precision format.We develop an implementation with the CUDA platform, which, on most recent graphics processing units (GPU), is nearly twice as fast and uses half the memory of the equivalent single-precision version. The error on seismograms caused by the reduced precision is shown to correspond to a negligible fraction of the total seismic energy and is mostly incoherent with seismic phases. Finally, we find that this noise does not adversely impact full-waveform inversion nor reverse time migration, which both benefit from the higher throughput of half-precision computation.

Uncontrolled Keywords

reverse time migration; full-waveform inversion; finite difference; algorithm; wave propagation

Open Access document in PolyPublie
Subjects: 1100 Génie des structures > 1107 Génie parasismique
2950 Mathématiques appliquées > 2960 Modélisation mathématique
Department: Département des génies civil, géologique et des mines
Research Center: Non applicable
Funders: CRSNG/NSERC
Grant number: Postdoctoral research fellowship
Date Deposited: 19 May 2021 11:42
Last Modified: 20 May 2021 01:20
PolyPublie URL: https://publications.polymtl.ca/6303/
Document issued by the official publisher
Journal Title: Geophysics (vol. 85, no. 3)
Publisher: Society of Exploration Geophysicists
Official URL: https://doi.org/10.1190/geo2018-0760.1

Statistics

Total downloads

Downloads per month in the last year

Origin of downloads

Dimensions

Repository Staff Only