Subduction is a fundamental component in plate tectonics. Here we focus on a prime example, the Sumatra subduction zone that has been the location of several destructive mega earthquakes with magnitude greater than 8 in the past centuries (e.g Henstock et al. 2006). The subduction zone is formed by the Australian plate moving into the Eurasian plate and ranges from the Himalayas in the north, to Timor in the south, but several parts of the plate move independently and the fault is highly segmented (McCaffrey 2009). Moreover there is a lot of variation in type of motion and earthquake risk along strike (Newcomb and McCann 1987) The subduction zone shows the whole range of subduction events, including slow slip events (Tsang et al. 2015) and subduction-related volcanism.

In this test example, we will evaluate the global background model of the 3D Earth project for modelling a subducting slab, the Sumatra subduction zone, addressing

  • Slab structure (density, geometry, gravity, gravity gradients)
  • 3D structure of the slab
  • Improvement of geometry in northern region
  • Improved constraints for dynamical modelling

Flowchart Sumatra

Flow chart of the Sumatra test area.