All the lakes of the state were formed by glaciation.
Many of them are at high elevations (Lake Victoria, 13,400 ft., being probably the most elevated), and are undoubted vestiges of an ancient period of glaciation.
Since the uplift and stream dissection a slight depression has allowed the sea to invade the lower portions of the river valleys, forming the bays known as Narragansett Bay, Providence "river," Sakonnet " river," &c. Glaciation has disturbed the river 1 Block Island, over which the jurisdiction of the state extends, lies Jo m.
The northern half is more broken and irregular; elevations, usually rounded, mingle with depressions some of which are occupied by small shallow lakes or ponds, the characteristic physical features of this region being due to glaciation.
Much interest attaches to estimates of time based on data afforded by the consequences of glaciation.