Millions of years ago it was the delta of the Colorado River until sediments created a dam across its mouth, and created a huge lake.
(it; was; the delta of the Colorado River; T:until sediments created a dam across its mouth, and created a huge lake; T:Millions of years ago) (sediments; created; a dam across its mouth) (sediments; created; a huge lake)
it sediments sediments
was created created
the delta of the Colorado River T:until sediments created a dam across its mouth, and created a huge lake T:Millions of years ago
a dam across its mouth
a huge lake