A robot using density- and resistance-based memory could locate damaged oil leaks by navigating the ocean environment without relying on vision or predefined maps, instead sensing how water, structures, and flow physically respond to its presence and emitted waves. As it moves, the robot probes with sonar or radar-like sensing to measure reflection, absorption, delay, and turbulence, building confidence patterns of normal versus abnormal resistance. Damaged wellheads, cracked pipes, or uncapped leaks create distinct signatures: unexpected density gradients, irregular flow resistance, and persistent absorption or scattering where smooth structural responses should exist. By following these anomalies—essentially moving “upstream” against least-resistance flow patterns—the robot converges on the source of the leak. Repeated passes reinforce the sweet spot where abnormal resistance and energy loss consistently recur, allowing the robot to identify and localize damage even in murky water, heavy sediment, or collapsed infrastructure where cameras and traditional mapping fail.