Interesting hypothesis but optical spectra & Mossbauer tell a chemical story.
from VISIBLE/NEAR INFRARED SPECTRAL CHARACTERIZATION OF IN SITU ROCK OUTCROPS AT
MERIDIANI PLANUM AS OBSERVED BY THE MARS EXPLORATION ROVER OPPORTUNITY by Farrand et al (PSC , 2005, 2082.pdf) they state "Vein/coating materials were
observed at Endurance crater in association with such
features as “Razorback”... These
coating/fracture fill materials were characterized by a
shallow 900 nm absorption feature- very similar to that
observed in the “rind” material at Shoemakers Patio in
Eagle crater. Examples of these materials subjected to
in situ examination display a stronger inner Fe3+ doublet
in Mössbauer spectra . The same mineral
phase(s) could be responsible for both features; possibilities
include, but are not limited to, schwertmannite,
akaganeite or ferrihydrite." That to my mind suggests chemistry in involved, not jus physcal rearrangement of existing dust particles.