Noun
tillite (plural tillites)
(geology) Glacial till cemented into a solid rock.
Tillite In cases where till has been indurated or lithified by subsequent burial into solid rock, it is known as the sedimentary rock tillite. Source: Internet
When the glacial sediments were turned into stone they formed the rocks that now make up the Fitzroy Tillite Formation in the Falklands. Source: Internet