GEMMA global Moho depth model

The GEMMA project (GOCE Exploitation for Moho Modeling and Applications), funded by the European Space Agency and Politecnico di Milano, aims at estimating the boundary between Earth's crust and mantle (the so called Mohorovicic discontinuity or Moho) from GOCE data in key regions of the world.

GEMMA@ESA-STSE

3D visualization of the GEMMA global Moho depth model (requires a browser that supports HTML5/WebGL): mohoViewer

The Earth’s crust makes up less than 1% of the volume of the planet however it is exceptionally important not just because we live on it, but also because it is the place where all our geological resources like natural gas, oil and minerals come from. Moreover the crust and the upper mantle are also the places where most geological processes of great importance, such as earthquakes, volcanism and orogeny, occur.

A fundamental parameter for the study of the Earth crust is its thickness, usually defined by a discontinuity surface, called Mohorovičić discontinuity or Moho from the name of the Croatian seismologist who discovered it in 1909, separating the upper mantle from the crust itself. Even if it is well known that the Moho can locally present very complex features, like duplications, fragmentations, subductions, etc., a sharp separation defined by a single surface well approximates its global behaviour.

The GEMMA project (GOCE Exploitation for Moho Modeling and Applications), funded by the European Space Agency and Politecnico di Milano, aimed at estimating the Moho depth from GOCE data in key regions of the world.

GEMMA1.0

GEMMA1.0 Moho depth models [km]

GOCE observations in fact represent an extremely innovative and useful product for the study of the Earth crust at regional and global scales: from the one hand they give a practically error-less constraint to verify crustal models, from the other hand combining GOCE gravity observations with seismic data and considering additional information it is possible to retrieve important information on the Earth crust structure.

After one year only of GOCE observations, thanks to the GEMMA project, it has been possible to globally estimate the depth of the boundary between the Earth’s crust and mantle, usually called Moho, with unprecedented resolution.

 

GEMMA_GOCE

 

The knowledge of the Moho is a key topic in Solid Earth sciences: the new GOCE Moho has been used, for instance, as background information to improve our ability to understand and model earthquakes or for the study of the Earth’s heat flux and heat production which in turn constitutes a basic knowledge to understand the plate tectonics and the thermal evolution of our planet.

List of publications:

  • Reguzzoni, M., & Sampietro, D. (2014). GEMMA: An Earth crustal model based on GOCE satellite data. International Journal of Applied Earth Observation and Geoinformation (link).
  • Reguzzoni, M., Sampietro, D., & Sansò, F. (2013). Global Moho from the combination of the CRUST2. 0 model and GOCE data. Geophysical Journal International (link).

 

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