Experimental shock deformation in zircon: a transmission electron microscopic study

Timing of crystallization of the lunar magma ocean constrained by the oldest zircon

“…The deformation bands are parallel to the crystallographic a-planes {010} of the zircon, have misorientation axes parallel to the c-axis, and are geometrically consistent with formation by dislocation creep associated with <100>{010} slip 21 . The deformation bands are geometrically similar to dislocation microstructures reported in experimentally shocked zircon 35 . We interpret these crystal-plastic deformation microstructures to have resulted from a significant impact, either directly from impact shock, or during ductile flow directly following the impact.…”

Analyses of shocked quartz at the global K-P boundary indicate an origin from a single, high-angle, oblique impact at Chicxulub

“…Three grains displayed strawberry texture, and this texture has previously been interpreted as a product of recrystallization under high-T conditions after shock-induced amorphization [41][42]. As for zircon from North American sites (e.g., [40,43]), the granular texture in the porous zircon from the European sites occurs beneath the original planar surface of subhedral grains (Fig. 4c).…”

Zircon to scheelite phase transition induced by pressure and magnetism inTbCrO4

“…Experimentally, Kusaba et al 27 concluded that the ͓110͔ direction in zircon-type structure becomes the ͓100͔ direction in the scheelite-type structure, consistent with an electron diffraction study that determined that the ͓110͔ direction of the scheelite-type structure is parallel to the ͓100͔ of the zircon-type one. 28 Bond breaking atom diffusion are not considered in this zircon-scheelite phase transition, only a more effective packing in the scheelite form due to the cooperative rotations of ͓SiO 4 ͔ tetrahedra, justifying the increase of 10% in density going from zircon to scheelite-form. These results point toward a the displacive-type structural transition.…”