Between tectonic plates and the mantle

While plate tectonics and mantle convection are well understood individually, scientists' understanding breaks down at the interface between the two. Here, a phenomenon known as strain localisation transfers energy from the convecting mantle into tectonic plates, resulting in tectonic activity.

To understand this process better, the INSIDE-STRAIN (In situ deformation experiments to study ductile strain localization) initiative created several laboratory methods to study strain localisation at the microscopic scale.

Researchers studied the phenomenon by reproducing strain localisation within ice and magnesium crystalline structures, and examining how these crystals changed under a scanning electron microscope. They used observations of natural strain localisation events to constrain their experimental model.

INSIDE-STRAIN identified the processes acting on crystals during strain localisation, and showed that fluids play the most important role here. The data generated was added to a database of ice recrystallisation events.

Scientists also produced maps of the ice recrystallisation process, based on this experimental data set. Lastly, INSIDE-STRAIN produced and published a new method for conducting this sort of experiment.

The methods and findings of INSIDE-DATA will improve models of strain localisation in the mantle, in glaciers and in polar ice sheets.