Complex sentence: It is thought that the eruption of the Archiflegreo volcano occurred about 39.28 ± 0.11 ka (older estimate ~ 37,000 years ago), erupting about of magma (bulk volume) to produce the Campanian Ignimbrite.
Split into simpler sentences: It is thought that the eruption of the Archiflegreo volcano occurred about 39.28 ± 0.11 ka. Abstract (older estimate ~ 37,000 years ago), erupting about of magma (bulk volume) to produce the Campanian Ignimbrite.