Campanian Ignimbrite eruption

The Campanian Ignimbrite eruption (CI, also CI Super-eruption) was a major volcanic eruption in the Mediterranean during the late Quaternary, classified 7 on the Volcanic Explosivity Index (VEI). The event has been attributed to the Archiflegreo volcano, the 12-by-15-kilometre-wide (7.5 mi × 9.3 mi) caldera of the Phlegraean Fields, located 20 km (12 mi) west of Mount Vesuvius under the western outskirts of the city of Naples and the Gulf of Pozzuoli, Italy. Estimates of the date and magnitude of the eruption(s), and the amount of ejected material have varied considerably during several centuries the site has been studied. This applies to most significant volcanic events that originated in the Campanian Plain, as it is one of the most complex volcanic structures in the world. However, continued research, advancing methods, and accumulation of volcanological, geochronological, and geochemical data have improved the dates' accuracy.

The most recent results by radiocarbon and argon–argon dating are, respectively, 39 220 to 39 705 calendar year BP and 39850±140 year BP. The estimated eruptive volume in dense-rock equivalent (DRE) is in the range of 181–265 km³ (43–64 cu mi), and tephra has dispersed over an area of around 3,000,000 km² (1,200,000 sq mi), commonly referred to as the ash horizon Y-5. The accuracy of these numbers is of significance for marine geologists, climatologists, palaeontologists, paleo-anthropologists and researchers of related fields as the event coincides with a number of global and local phenomena, such as widespread discontinuities in archaeological sequences, climatic oscillations and biocultural modifications.