This rapid down-cutting of the Illinois River Valley left the tributaries of the Illinois River hanging at their original height, forming the canyons we see today.
(the tributaries of the Illinois River; hanging; L:at their original height) (the canyons; see; T:today) (This rapid down-cutting of the Illinois River Valley; left; the tributaries of the Illinois River; hanging at their original height) Context(This rapid down - cutting of the Illinois River Valley left,List([0, 57))):(This rapid down-cutting of the Illinois River Valley; left the tributaries of the Illinois River forming; the canyons we see today)
This rapid down - cutting of the Illinois River Valley left,List([0, 57))
the tributaries of the Illinois River the canyons This rapid down-cutting of the Illinois River Valley This rapid down-cutting of the Illinois River Valley
hanging see left left the tributaries of the Illinois River forming
L:at their original height
T:today
the tributaries of the Illinois River hanging at their original height
the canyons we see today