Spectral harmonic analysis and synthesis of Earth's crust gravity field

Robert Tenzer, Pavel Novák, Peter Vajda, Vladislav Gladkikh, Hamayun

Research output: Journal article publicationJournal articleAcademic researchpeer-review

57 Citations (Scopus)

Abstract

We developed and applied a novel numerical scheme for a gravimetric forward modelling of the Earth's crustal density structures based entirely on methods for a spherical analysis and synthesis of the gravitational field. This numerical scheme utilises expressions for the gravitational potentials and their radial derivatives generated by the homogeneous or laterally varying mass density layers with a variable height/depth and thickness given in terms of spherical harmonics. We used these expressions to compute globally the complete crust-corrected Earth's gravity field and its contribution generated by the Earth's crust. The gravimetric forward modelling of large known mass density structures within the Earth's crust is realised by using global models of the Earth's gravity field (EGM2008), topography/bathymetry (DTM2006. 0), continental ice-thickness (ICE-5G), and crustal density structures (CRUST2. 0). The crust-corrected gravity field is obtained after modelling and subtracting the gravitational contribution of the Earth's crust from the EGM2008 gravity data. These refined gravity data mainly comprise information on the Moho interface and mantle lithosphere. Numerical results also reveal that the gravitational contribution of the Earth's crust varies globally from 1,843 to 12,010 mGal. This gravitational signal is strongly correlated with the crustal thickness with its maxima in mountainous regions (Himalayas, Tibetan Plateau and Andes) with the presence of large isostatic compensation. The corresponding minima over the open oceans are due to the thin and heavier oceanic crust.
Original languageEnglish
Pages (from-to)193-207
Number of pages15
JournalComputational Geosciences
Volume16
Issue number1
DOIs
Publication statusPublished - 1 Jan 2012
Externally publishedYes

Keywords

  • Crust
  • Forward modelling
  • Gravity field
  • Spectral representation
  • Synthetic model of the Earth

ASJC Scopus subject areas

  • Computer Science Applications
  • Computers in Earth Sciences
  • Computational Theory and Mathematics
  • Computational Mathematics

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