  Characteristic shock effects in silica serve as a key indicator of historical
impacts at geological sites. Despite this geological significance, atomistic
details of structural transformations under high pressure and shock compression
remain poorly understood. This ambiguity is evidenced by conflicting
experimental observations of both amorphization and crystallization
transitions. Utilizing a newly developed machine-learning interatomic
potential, we examine the response of $\alpha$-quartz to shock compression with
a peak pressure of 60 GPa over nano-second timescales. We initially observe
amorphization before recrystallization into a d-NiAs-structured silica with
disorder on the silicon sublattice, accompanied by the formation of domains
with partial order of silicon. Investigating a variety of strain conditions
enables us to identify the non-hydrostatic stress and strain states that allow
the direct diffusionless formation of rosiaite-structured silica.
