The oceanic zone at depths of 200–2000 m, lying to the seaward of the shallower neritic zone, and landward of the deeper abyssal zone. The upper limit of the bathyal zone is marked by the edge of the continental shelf. In marine ecology, it is the region of the continental slope and rise. It may be geologically active, and include trenches and submarine canyons, with underwater erosion producing avalanches.
Subjects: Ecology and Conservation — Earth Sciences and Geography.