The world’s largest iceberg appears to have run aground off the coast of a remote British island home to millions of penguins and seals — potentially threatening local wildlife, but also providing an opportunity for research into such rare “megabergs.”

Known as A23a, the massive slab of ice — roughly the size of Rhode Island and weighing nearly a trillion tonnes — was first reported to be heading toward South Georgia months ago, sparking concerns that it could collide with the island and disrupt the balance for local wildlife.

The British Antarctic Survey (BAS) said Tuesday that the iceberg had apparently struck the continental shelf that surrounds South Georgia, getting stuck roughly 73 kilometres from the island itself.