The dark-matter problem is usually framed as the search for an unseen particle component. This paper develops a geometric hypothesis: a significant part of dark-matter phenomenology may be the gravitational imprint of persistent defect-like textures in an emergent spacetime medium. Building on the Enchan Field framework, we model spacetime order by a dimensionless geometric field whose finite-tension relaxation can support long-lived geometric textures, referred to here as "spacetime wrinkles." A logarithmic effective profile produces a 1/r field gradient, which yields flat galactic rotation curves in the weak-field regime. With a baryonic anchoring condition, the same structure provides a candidate mechanism for the characteristic acceleration scale appearing in the Radial Acceleration Relation (RAR) and the Baryonic Tully-Fisher Relation (BTFR). This manuscript establishes a falsifiable research program for geometric dark-sector modeling, explicitly separating phenomenological targets from microphysical derivations, and outlining necessary consistency checks against cluster mergers, CMB constraints, and high-acceleration Solar-System limits. Related Enchan Project Materials: * The Enchan Field (Core Framework): https://doi.org/10.5281/zenodo.20121394 * Enchan Field Notes (Mathematical Precursor): https://doi.org/10.5281/zenodo.17979664 * Computational Validation (Proof-of-Reality Engine): https://doi.org/10.5281/zenodo.18139449
Mitsuhiro Kobayashi (Sun,) studied this question.