Spawns patches of Clay, Sand, and Dirt, within the Ocean type biome floors (spawning in the sand/gravel surface layers of the ocean floor, as well as some gravel below ocean biomes. applies to all temperatures)
1.16 example: https://github.com/Lothrazar/OceanFloorControl/blob/trunk/1.16/oceanfloor.toml
In newer mminecraft versions these are controled bo the Mojang standard JSON files as regular placed features
