The dominant mega-province in eastern North America is the Appalachian Highlands , consisting of several provinces, which contain rocks ranging in age from about 570 to 245 million years (m.y.) They have been involved in several major episodes of mountain building, culminating in the Appalachian Revolution about 250 m.y. ago.
(The dominant mega-province in eastern North America; is; the Appalachian Highlands) (The dominant mega-province in eastern North America; consisting; of several provinces) (several provinces; contain; rocks ranging in age from about 570 to 245 million years (m.y.)) (rocks; ranging; in age; from about 570 to 245 million years) (They; have been involved; in several major episodes of mountain building)
The dominant mega-province in eastern North America The dominant mega-province in eastern North America several provinces rocks They
is consisting contain ranging have been involved
the Appalachian Highlands
of several provinces
rocks ranging in age from about 570 to 245 million years (m.y.)
in age from about 570 to 245 million years
in several major episodes of mountain building