Complex sentence: From 545 to 390 MYA there were shallow warm seas over parts of central Australia, with a series of volcanic arcs and deep water sedimentation in the east, during this period between 480 to 460 MYA the Larapinta Seaway ran across the centre of Australia.
Split into simpler sentences: From 545 to 390 MYA shallow warm seas covered parts of central Australia, with a series of volcanic arcs and deep water sedimentation in the east. During this period between 480 to 460 MYA the Larapinta Seaway extended across the centre of Australia.