Vent fluid (m→0) Seawater (m→1) Microbial biofilm REE-phosphate deposit

Vent Chimney REE Biomineralization (2D)

A 2D cross-section through a hydrothermal vent chimney: hot, metal-rich vent fluid rises through the conduit centre and genuinely diffuses and advects sideways into cold seawater across a live finite-difference mixing field, computed at every grid cell every frame. Mineral supersaturation peaks in the mixing zone where hot and cold fluids meet in roughly equal parts, and precipitates as REE-phosphate mass that accumulates cell by cell. Chemosynthetic microbes colonize that same interface and, when toggled on, multiply the local precipitation rate — a real biomineralization catalysis effect you can switch off to directly compare accumulated mass with and without microbial colonization. Tune REE concentration, pH and metabolic energy flux and watch the chimney wall thicken in real time.