Moho Modeling Using FFT Technique

Wenjin Chen, Robert Tenzer

Research output: Journal article publicationJournal articleAcademic researchpeer-review

3 Citations (Scopus)

Abstract

To improve the numerical efficiency, the Fast Fourier Transform (FFT) technique was facilitated in Parker–Oldenburg’s method for a regional gravimetric Moho recovery, which assumes the Earth’s planar approximation. In this study, we extend this definition for global applications while assuming a spherical approximation of the Earth. In particular, we utilize the FFT technique for a global Moho recovery, which is practically realized in two numerical steps. The gravimetric forward modeling is first applied, based on methods for a spherical harmonic analysis and synthesis of the global gravity and lithospheric structure models, to compute the refined gravity field, which comprises mainly the gravitational signature of the Moho geometry. The gravimetric inverse problem is then solved iteratively in order to determine the Moho depth. The application of FFT technique to both numerical steps reduces the computation time to a fraction of that required without applying this fast algorithm. The developed numerical producers are used to estimate the Moho depth globally, and the gravimetric result is validated using the global (CRUST1.0) and regional (ESC) seismic Moho models. The comparison reveals a relatively good agreement between the gravimetric and seismic models, with the RMS of differences (of 4–5 km) at the level of expected uncertainties of used input datasets, while without the presence of significant systematic bias.
Original languageEnglish
Pages (from-to)1743-1757
Number of pages15
JournalPure and Applied Geophysics
Volume174
Issue number4
DOIs
Publication statusPublished - 1 Apr 2017
Externally publishedYes

Keywords

  • Crust
  • gravity
  • lithosphere
  • Moho
  • spherical harmonics

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology

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