After the Ice Age, when the glaciers retreated, deep furrows or valleys were left behind, and 10-15,000 years ago, the Red Deer River Valley was carved out as a result of the flood waters from melting glaciers.
(the glaciers; retreated; ) (deep furrows or valleys; were left; behind; T:After the Ice Age; T:when the glaciers retreated) (the Red Deer River Valley; was carved out; as a result of the flood waters from melting glaciers; T:10-15,000 years ago)
the glaciers deep furrows or valleys the Red Deer River Valley
retreated were left was carved out
behind T:After the Ice Age T:when the glaciers retreated
as a result of the flood waters from melting glaciers T:10-15,000 years ago