According to Colin Richardson, this cup marked stone is thought to have once been upright, and accumulated cairn material about it's base afterwards. Presumably this material was removed during the excavation. Dating was inconclusive, though the usual late Neolithic/early bronze age period was assumed.
Excavations on a cup-&-ring marked boulder on Tortie Hill.
(Transactions of the Cumberland and Westmorland Antiquarian & Archaeological Society, 92, 1992, 7–11, ISSN 0309-7986):