  We describe and constrain the origins of ISM structures likely created by
ongoing ICM ram pressure stripping in two Virgo Cluster spirals, NGC 4522 and
NGC 4402, using HST BVI images of dust extinction and stars, as well as
supplementary HI, Halpha, and radio continuum images. This is the
highest-resolution study to date of the physical processes that occur during an
ICM-ISM ram pressure stripping interaction, ram pressure stripping's effects on
the multi-phase, multi-density ISM, and the formation and evolution of
ram-pressure-stripped tails. In dust extinction, we view the leading side of
NGC 4402 and the trailing side of NGC 4522; we see distinct types of features
in both galaxies. NGC 4522 has experienced stronger, more recent pressure and
has the jellyfish morphology characteristic of some ram pressure stripped
galaxies. Its stripped tail extends up from the disk plane in continuous
upturns of dust and stars curving ~2 kpc above the disk plane. A kinematically
and morphologically distinct extraplanar arm of young, blue stars and ISM
extends above a mostly-stripped portion of the disk, and between it and the
disk plane are decoupled dust clouds. NGC 4402 contains long dust ridges,
suggesting that large parts of the ISM are being pushed out at once. Both
galaxies contain long ridges of polarized radio continuum emission indicating
the presence of large-scale ordered magnetic fields. We propose that magnetic
fields could bind together gas of different densities, causing nearby gas of
different densities to be stripped at the same rate and creating the large,
coherent dust ridges and upturns. A number of factors that play roles in
determining what types of structures form as a result of ram pressure: ram
pressure strength and history, the location within the galaxy relative to the
leading side, and pre-existing substructure in the ISM that may be bound
together by magnetic fields.
