Complex sentence: During other times in its past, Laurentia has been part of larger continents and supercontinents and itself consists of many smaller terranes assembled on a network of Early Proterozoic orogenic belts.
Split into simpler sentences: During other times in its past, Laurentia has been part of larger continents and supercontinents. Laurentia owes its existence to a network of Early Proterozoic orogenic belts.