arch excavation site
The Excavation Site: What the Stratigraphy Tells Us About That Day
Vesuvius' eruption was not simply an 'explosion.' Archaeologists call this a 'Plinian eruption' — a volcanic cloud at least 15 km in diameter and 30 km high. Reading the process through excavation stratigraphy: [Layer 1: Lapilli Fallout (8-10 hours)] Starting around 1 PM on August 24, 79 CE, the explosion first showered pumice and ash. Pumice accumulated in Pompeii at approximately 10-20 cm per hour. Many citizens escaped during this phase. Roof collapses killed those who remained indoors. [Layer 2: High-Temperature Pyroclastic Surge (18-20 hours)] At dawn the next day, as the volcanic column collapsed, 300-400°C gas and ash at 100 km/h swept the city. This pyroclastic surge caused the majority of deaths. Residents who had not evacuated died instantly at this moment — not from asphyxiation but from instantaneous heat death. [Layer 3: Ash Sealing Layer (final burial)] The entire city was buried under 4-6 meters of ash and pumice. This sealing preserved Pompeii for 1,700 years. Fiorelli's Plaster Casting Method (1863): Injecting plaster into the voids within the volcanic ash restores the final postures of victims. To date, over 1,150 sets of remains have been discovered — less than 10% of Pompeii's population (estimated 11,000-20,000). Most successfully escaped.