_:b1218286 "Wikipedia:Pockmark"^^ . _:b1218286 "Pockmarks are craters in the seabed resulting from the release of gas or liquid. Generally, they are formed in soft, fine-grained seabed sediments by the escape of fluids (gas or water, but mainly methane) into the water column."^^ . _:b1218286 . _:b1218286 . _:b1218286 "PLB:plb"^^ . _:b1218286 .