HIGH-PRESSURE MINERAL SHAPE FABRICS REVEAL 3D STRAIN VARIATION IN THE DEEP CONTINENTAL CRUST

Elongate rutile (TiO2) in a ~3.5 x 2.5 cm block of eclogite, a high-pressure rock composed of garnet, pyroxene, rutile, and quartz. The sample is from the Montagne Noire structural dome, France. Imaging of a similar rock from another region of the Montagne Noire dome yielded a different fabric, documenting variation in strain under high-pressure conditions of the deep crust during the late stages of evolution of this mountain system.

 

 

 

Videos showing slices through 3D volumes. All phases (top left) Quartz (top right) Garnet (bottom left) Rutile (bottom right). Click image to see video.

In the All phases video different colors correspond to different phases: Quartz is dark blue, garnet is green, rutile is yellow, and red is matrix. In the videos for individual phases different colors correspond to unique grains.