Sea Base Four Oceanic Fault

Beneath Sea Base Four, the seafloor fractures along an active oceanic fault, a jagged gash in the Earth's crust where tectonic plates grind together. The abyssal darkness here is only partially pierced by the base's searchlights, revealing sheer rock faces striated with mineral veins that glow faintly from geothermal heat. The water churns with upwellings of superheated brine, creating shimmering thermal veils that distort sonar readings. Hydrothermal vents billow dark plumes, the scent of sulfur lingering even through the reinforced hull. The fault's continual tremor vibrates through the base's legs, a subsonic pulse that syncs with the crew's unease as they debate the origin of the anomalous object just beyond these unstable depths.