| Popis: |
The ad 79 eruption of Vesuvius buried several towns under tens of metres of ash, including Pompeii and Herculaneum. The latter was a coastal town located approximately 7 km from the vent; it was hit by a pyroclastic surge, a wave of hot gas and ash, as the people waited for rescue boats in boathouses and on the beach. The current study examines thermal damage to 150 men, women and children from Herculaneum excavated in the 1980s and 1990s. Although 96.6% of the people have some thermal alteration, only a small fraction, approximately 15%, have a calcined bone (one that reached 700°C or higher). Moreover, those bones with calcined aspects are those that are shielded by thin layers of soft tissue, like adult tibiae and subadult crania. Parts of the skeleton covered with thick tissues, like the abdomen, have very light thermal damage. Thus, it is clear the surge was initially hot enough to calcine bone but that temperature only lasted long enough to burn through thin layers of soft tissue. The temperature subsided as the ash and debris settled onto the ground. Bones covered by thicker soft tissues have thermal damage indicating, for the most part, they only reached temperatures up to 300°C. Soft tissues shielded the bones for hours or perhaps days, but eventually the heat affected almost every skeleton. |
