The glaciers eroded preexisting deposits, veneered the upland, and filled valleys with unconsolidated deposits that changed surface-water drainage and altered groundwater gradients.
(The glaciers; eroded; preexisting deposits) (The glaciers; veneered; the upland) (The glaciers; filled; valleys; with unconsolidated deposits) (unconsolidated deposits; changed; surface-water drainage and altered groundwater gradients)
The glaciers The glaciers The glaciers unconsolidated deposits
eroded veneered filled changed
preexisting deposits
the upland
valleys with unconsolidated deposits
surface-water drainage and altered groundwater gradients