ocean floor
ocean bed

She swam away and down to the ocean bed with him, laughing.

Surely they must be well below the ocean bed now.

They had to return to the ocean bed as quickly as possible.

He saw the first charge plunge into the water on his right and fall towards the ocean bed.

Reaching bottom, he prowled about the ocean bed for a while, then started up again.

Once more the Advance settled to the ocean bed, near the wreck.

Only in the last century scientists were saying that there could be no life at all on the ocean bed.

The earthquake killed some, and the rest died for want of water after the ocean bed rose to the air.

Once, this must have been a lake or an ocean bed.

We have planted them in different spots on the ocean bed.