Complex sentence: They are Ordovician in age, deposited as turbidites about 480 million years ago in the Iapetus Ocean, and heavily folded and lightly metamorphosed in late Ordovician times.
Split into simpler sentences: They are Ordovician in age, deposited as turbidites about 480 million years ago in the Iapetus Ocean. They were heavily folded and lightly metamorphosed in late Ordovician times.