https://phys.org/news/2018-11-potentially-channels-antarctic-ice-shelves.html

However, with new technology researchers are able to study them in greater detail than ever before, even looking through kilometres-thick glaciers to view processes occurring at their bases.

The team, including researchers from universities in the UK and the US, used ice-penetrating radar mounted on planes to peer through the glacier and work out what is happening at its base.