Chemical analysis revealed it to be rich in irons and iron oxides, most likely originating from the blood and bodily fluids of the victims. In addition, many of the Pompeii victims were found in fully contorted poses, indicating that their muscles had contracted very quickly upon being exposed to high heat.
Those in Herculaneum seemed to show muscle contraction in some limbs but not others. According to the new study, this supports the idea that extreme heat could have destroyed certain muscles faster than they could contract. Jaskulska says that some independent forensic evidence supports the idea that red blood cell destruction can cause this sort of bone staining.
This heat is comparable to what victims would have experienced in Herculaneum. This seems odd to her, considering that there are far more soft tissues to vaporize on legs than on arms. Jaskulska also expected that if these tissues disappeared due to sudden heat, the damage to the bones would be much more intense than it appears.
Even if heat-driven hemoglobin breakdown did occur, the pyroclastic surges might have caused the damage after the people had already died of asphyxiation or other causes. Modern analogs may shed some light on the debate.
Janine Krippner , a volcanologist at Concord University in Athens, West Virginia, points out that pyroclastic flows and surges still happen today, and they are not always a guarantee of a quick, painless demise. The outcome depends on how fast, hot, ashy, and gassy the currents are, among other things.
If it is diluted enough, you might even be able to survive the severe heat-related trauma. All rights reserved. Share Tweet Email. Read This Next Wild parakeets have taken a liking to London. Animals Wild Cities Wild parakeets have taken a liking to London Love them or hate them, there's no denying their growing numbers have added an explosion of color to the city's streets. India bets its energy future on solar—in ways both small and big. Environment Planet Possible India bets its energy future on solar—in ways both small and big Grassroots efforts are bringing solar panels to rural villages without electricity, while massive solar arrays are being built across the country.
Epic floods leave South Sudanese to face disease and starvation. Travel 5 pandemic tech innovations that will change travel forever These digital innovations will make your next trip safer and more efficient. But will they invade your privacy? The volcano also has a semicircular ridge called Mount Somma that rises to 3, feet 1, m. Mount Vesuvius is considered to be one of the most dangerous volcanoes in the world because of its proximity to the city of Naples and the surrounding towns on the nearby slopes.
The volcano is classed as a complex stratovolcano because its eruptions typically involve explosive eruptions as well as pyroclastic flows. A pyroclastic flow is a high-density mix of hot lava blocks, pumice, ash and volcanic gas, according to the U. Geological Survey. Vesuvius and other Italian volcanoes, such as Campi Flegrei and Stromboli, are part of the Campanian volcanic arc. The Campanian arc sits on a tectonic boundary where the African plate is being subducted beneath the Eurasian plate.
Under Vesuvius, scientists have detected a tear in the African plate. This "slab window" allows heat from the Earth's mantle layer to melt the rock of the African plate building up pressure that causes violent explosive eruptions. In the past, Mount Vesuvius has had a roughly year eruption cycle, but the last serious eruption was in Mount Vesuvius destroyed the city of Pompeii, a city south of Rome, in A. Because the city was buried so quickly by volcanic ash, the site is a well-preserved snapshot of life in a Roman city.
There is also a detailed account of the disaster recorded by Pliny the Younger, who interviewed survivors and recorded events in a letter to his friend Tacitus. Pompeii was established in B. The shallow quake, originating beneath Mount Vesuvius, had caused major damage to the springs and piping that provided the city's water.
Reconstruction was being carried out on several temples and public buildings. Seneca, a historian, recorded that the quakes lasted for several days and also heavily damaged the town of Herculaneum and did minor damage to the city of Naples before subsiding. The major quake was followed by several minor shakes throughout the following years. Because seismic activity was so common in the area, citizens paid little attention in early August of 79 when several quakes shook the earth beneath Herculaneum and Pompeii.
People were unprepared for the explosion that took place shortly after noon on the 24th of August. Around 2, residents survived the first blast. Pliny the Elder , a Roman author, described the massive debris cloud. The same account reveals, however, that the signs were there. Pliny's casual reference to earth tremors 'which were not particularly alarming because they are frequent in Campania' reveals the Roman's comprehensive ignorance of the link between seismic activity earth tremors and volcanic activity.
The volcanologists of today constantly monitor any changes in levels of seismic activity from the observatory on Vesuvius, because they know that the same increase of activity in the deep reservoir of magma molten or partially molten rock beneath the Earth's surface causes both earth tremors and volcanic eruptions.
Through measuring seismic activity, these scientists expect to predict an approaching eruption months in advance. They also know that the activity of Vesuvius is recurrent, and that the longer the intervals between one eruption and another, the greater the eventual explosion will be.
The frequent but low-level activity of Vesuvius in recent centuries has relieved the build-up of pressure in the magma chamber.
The catastrophic magnitude of the eruption of AD 79 was connected with the extended period of inactivity that preceded it. A long interval combined with mounting seismic activity is a sure sign of impending disaster. Of course, the Romans could not know this, and our own knowledge owes much to the care of Pliny's description.
The long inactivity of the volcano naturally lulled the people of the region into a false sense of security, though they were aware of the signs of burning at the peak of the mountain. They were not the first to be so lulled: recent excavations at the site of the new NATO base at Gricignano, on the north of the Bay, have revealed two catastrophic eruptions that preceded that of 79, and wiped out the populations of a densely occupied territory.
The most important earlier eruption, known as that of the 'Avellino pumice' occurred around BC; several sites, especially one near Nola, reveal the destruction of Bronze Age settlements, with their huts and pots and pans and livestock. But of this the Romans knew nothing. The irony of this is that the Romans were extremely interested in predicting the future, and they had a range of ways to detect what they saw as the approaching wrath of the gods.
They were adept, for example, at observing 'portents' in the shape of strange sights and sounds, or unusual births. Even in these terms, there were warnings of the eruption of Vesuvius. Earthquakes in themselves counted as portentous, and the historian Cassius Dio, writing over a century later, reports repeated sightings of giants roaming the land.
This was a bad portent indeed, given that one standard explanation for the volcanoes of south Italy was that, when the gods defeated the rebellious giants and brought peace to the universe, they buried them beneath the mountains, and that it was their stirrings that caused the eruptions.
But while the ancient imagination doubtless conjured up giants in plumes of gas from fumaroles vents from which volcanic gas escapes into the atmosphere , the earthquakes that Pliny described so casually were more than just portents. Current thinking, however, had not yet caught up with their significance. We know this because, by an extraordinary coincidence, the philosopher Seneca, advisor to the emperor Nero, wrote a discussion of the scientific causes of earthquakes only a few years before the eruption.
Seneca's treatise on the causes of natural phenomena included an entire book on earthquakes, and at the time he was writing, the news was coming in freshly of the catastrophic earthquakes in Campania of AD 63, which caused extensive damage to both Pompeii and Herculaneum. Seneca writes that he regarded it as likely that earthquakes in different parts of the world were interconnected, and even that they were linked to stormy weather, but he draws no link with volcanic activity.
Indeed, he goes so far as to reproach the landowners who were deserting Campania for fear of further earthquakes. Some areas seem to have been worse affected than others - there are cases where entire houses were demolished and reduced to agricultural land. Upper floors would have been particularly badly affected - and indeed some buildings do have blocked-up doors at the top, indicating that the higher floors had been abandoned.
But more impressive than the signs of damage are the signs of the resilience of the local population. Damaged houses were being extensively repaired and redecorated at the time of the AD 79 eruption, and there was a comprehensive programme of restructuring of public buildings in the Forum of Pompeii.
The evidence points to a continuous process of repairs and rebuilding from AD 63 onwards. It used to be assumed that the earthquake described by Seneca was the only cause of damage, and that signs of incomplete work suggested that it took the cities a long time to recover from the first catastrophe.
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