Hydra-Flux Technical Memorandum

This preprint is an early Hydra‑Flux conceptual technical memorandum (TRL 2), preserved for traceability as part of an iterative design process. It proposes a hypothesis-level systems architecture for offshore methane hydrate production in unconsolidated sediments and related mobility-control use cases. Status: conceptual only; no laboratory validation, no field testing, no certified engineering design. Quantitative values are design envelopes / baseline hypotheses. Core disclosed elements (hypothesis-level): Sequential brine conditioning concepts (e.g., KCl → NaCl → CaCl₂) intended to manage clay/fines behavior and stress-path sensitivity. Progressive / dynamic volume replacement concept using waste-derived mineral feedstocks as injected structural fill (geopolymer/mineral skeleton), intended to reduce compaction/subsidence risk (site-gated). Optional mechanical decoupling concepts for infrastructure integrity (interface/damping layer), and optional CO₂-related dissociation/mineral interaction loops (site-gated). Superseded by (normative reference): Hydra‑Flux Master Compendium — 10.5281/zenodo.19699052.