  Supersonic isothermal turbulence establishes a network of transient dense
shocks that sweep up material and have a density profile described by balance
between ram pressure of the background fluid versus the magnetic and gas
pressure gradient behind the shock. These rare, densest regions of a turbulent
environment can become Jeans unstable and collapse to form pre-stellar cores.
Using numerical simulations of magneto-gravo-turbulence, we describe the
structural properties of dense shocks, which are the seeds of gravitational
collapse, as a function of magnetic field strength. In the regime of a weak
magnetic field, the collapse is isotropic. Strong magnetic field strengths lead
to significant anisotropy in the shocked distribution and collapse occurs
preferentially parallel to the field lines. Our work provides insight into
analyzing the magnetic field topology and density structures of young
protostellar collapse, which the theory presented here predicts are associated
with large-scale strong shocks that persist for at least a free-fall time.
