Mantle Transition Zone Topography Model Beneath South America

The dynamic processes in the Earth’s mantle are strongly affected by the properties of the mantle transition zone (MTZ), a layer that controls the circulation of heat and compositional materials in the mantle. The boundary of the MTZ is characterized by two seismic discontinuities at 410 km and 660 km depths that are associated with mineral phase transitions. The recent expansion of global seismic arrays has improved our ability for high-resolution imaging of deep Earth structure related to important questions on the Earth’s internal physics and chemistry. We take advantage of a global dataset of seismic records of teleseismic earthquakes to image upper mantle discontinuities beneath South America, one of the least explored continental plates regarding its geological evolution. Data are being characterized by travel times of underside reflections from the discontinuities (also known as SS precursors).