The point at which an outlet glacier no longer lies on bedrock but starts to float over an open body of water as an ice shelf.
The grounding line is located in a zone where the part of the glacier that is above water is balanced by the buoyancy of the part of the glacier that is underwater. Icebergs can be detach from the floating part of the glacier, or ice shelf, and can be as thick as the entire ice shelf is tall.
When a glacier’s terminus is located at the bottom of a body of water, it is called a grounding glacier.
Ice shelf’s scheme