MAP: The Mohorovivic discontinuity in Southamerica - ESA

The European Spatial Agency (ESA) has just published the first global high resolution map of the boundary between Earth's Crust and Mantle - mostly known as MOHO -. The map has been produced based on data from the GOCE gravity satellite. An improved image and knowledge of the Moho will offer new clues about the dynamics earth's interior.
The region between the crust and upper mantle is the place where most geological process occur, such as earthquakes, volcanism and orogeny; most resources including natural gas, oil and minerals comes from there to make possible our daily live.
Until just a century ago, we didn’t know Earth has a crust. In 1909, Croatian seismologist Andrija Mohorovičić found that at about 50 km underground there is a sudden change in seismic speed. Ever since, that boundary between Earth’s crust and underlying mantle has been known as the Mohorovičić discontinuity, or Moho.

Two methods are used to distinguish the different layers of earth's interior: seismic and gravimetric. Seismic uses the treveltime of the seismic waves. Gravimetry looks at the gravitational effect due to the density difference caused by the changing composition of crust and mantle.

The GOCE Exploitation for Moho Modelling and Applications project – or GEMMA – has now generated the first global high-resolution map of the boundary between Earth’s crust and mantle based on data from the GOCE satellite.
For the first time, it is possible to estimate the Moho depth worldwide with unprecedented resolution, as well as in areas where ground data are not available. This will offer new clues for understanding the dynamics of Earth’s interior, unmasking the gravitational signal produced by unknown and irregular subsurface density distribution.

(Map from the European Spatial Agency)