SCIENCE NOTES  
Summer 1998

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S H A K I N G      H I S T O R Y

At the end of the Bronze Age, over 50
Mediterranean cities fell during a 50-year period.
Were earthquakes responsible?

By Christie Aschwanden


ARCHAEOLOGISTS have long puzzled over a strange finding in the eastern Mediterranean. They've unearthed over 50 cities in this region, and found that all were destroyed within the fifty year period between 1225 BC and 1175BC. The fall of these centers marks the end of the Bronze Age, which lasted from 3,000BC to about 1,000BC. During this time, art and literature flourished and bronze technology pushed Middle Eastern societies towards new innovations in tools and architecture. During the "mini dark age" that followed the Bronze Age, the written language Linear B disappeared and artistic pursuits were abandoned.
      For years, historians and archaeologists have debated how these civilizations fell without reaching a consensus. Some scholars, like ancient historian Robert Drews of Vanderbilt University and author of "The End of the Bronze Age", believe warfare destroyed the civilizations. Others, like archaeologist Eric H. Cline of Xavier University, believe a multitude of factors were responsible. But Stanford geophysicist Amos Nur thinks geology explains these civilizations' downfalls. Nur's theory: earthquakes destroyed the cities.

AT FIRST, Nur couldn't find an audience among archaeologists and historians. But he refused to give up, and finally he persuaded Cline that geology could contribute to archaeology. Now Cline is helping him reach ancient scholars by speaking their language.
      Nur didn't set out to study ancient history. Twenty-five years ago, earthquake prediction was geophysics' hottest field, and Nur was searching for ways to refine his earthquake prediction theories. "We needed a way to test these schemes against real records, and I had the naive idea that maybe I'd look at the past for clues," Nur says. Recognizing that the eastern Mediterranean has a written history dating back ten thousand years, he began digging through the Holy Land's texts looking for records of ancient earthquakes.
      That's when Nur made an unexpected find. While not enough to test his theories, the 32 earthquakes Nur found in the Holy Land's historical records led him to a startling conclusion: The region's earthquakes could have driven the catastrophic collapse of eastern Mediterranean civilizations at the end of the Bronze Age. "Instead of learning about earthquakes from archaeology, we ended up learning about archaeology from earthquakes!" Nur wrote in a 1997 International Geology Review paper. The first line of evidence, he says, lies in the region's active fault system. Three faults dissect the eastern Mediterranean, and Nur says they've plagued the region with earthquakes for thousands of years. Modern seismic data show that earthquakes have rocked virtually every Bronze Age site in the area during the last 100 years. Based on the fault system's layout, there is "Absolutely no question Jericho was hit and devastated by earthquakes every few hundred years," Nur says.
      But Nur also believes the archaeological evidence is unequivocal. At Israeli sites, huge marble pillars are knocked over on their sides--all in the same direction, and keystones in mighty stone arches are slipped out of position. Human skeletons crushed under stone ruins have been uncovered at a handful of sites. Nur argues these skeletons are signs of earthquake fatalities since, "We don't bury people under rubble." Other evidence includes: walls sitting at an angle at some sites; walls offset, where the right side is moved above the left; and sites where walls are completely toppled.

NUR IS NOT the first to suggest earthquakes were a major player in the region's history, but he's given the idea new life. In the late 1940's, archaeologist Claude Schaeffer published a paper and later a book blaming earthquakes for the great Middle Eastern cities' fall at the end of the Bronze Age. Schaeffer's work met with great resistance from the archaeology community. "Schaeffer was famous before the book, and infamous after," Nur says. He is not merely picking up Schaeffer's theory-he's backing it up with hard scientific evidence. But while scholars are slowly warming to the quake theory, Nur's recent attempts at popularizing it still haven't gained wide acceptance.
      One reason is that archeologists resent "an outsider coming in and thinking he can do better something we've been training our whole lives to do," Xavier archaeologist Cline says. And Nur's approach has made matters worse. "Nur's tone has been that of an enthusiastic bystander," says Cline. "At first, Nur said quakes ended the Bronze Age, that's not the case. But earthquakes may have contributed to the end of the Bronze Age," Cline says. Bold proclamations like that make archaeologists wary. "There are forbidden topics in archaeology and if you really want to be considered a serious scholar, you must avoid them," Cline says. Nur's early work on the theory invoked Bible passages and myths of Armageddon, which Cline believes reduced his credibility with serious scholars.
      Nur contends scholars resist the notion earthquakes ended the Bronze Age is that, "Historians don't want to accept that random events changed history." As evidence, he cites a 1991 paper by Elizabeth French, former director of the British School of Archaeology and a leading excavator at Mycenae, "Archaeologists of my generation who attended university in the immediate aftermath of Schaeffer's great work in 1948, were brought up to view earthquakes, like religion, as an explanation of archaeological phenomena to be avoided if at all possible."
      But Vanderbilt historian Drews disagrees that historians resent random events, "I think we have to accept it (a random event) when it's fact. What historians would object to is the random resort to either supernatural or very unusual or unprecedented events of this kind (to explain history). I don't know of any place in antiquity where an earthquake ever destroyed a city," Drews says, "but we know of thousands of places destroyed by human beings." He says scientists are overly anxious to apply their trades to history. "Scientists may prefer to think that some of these interesting events have natural causes rather than human ones, so they're eager to find natural disasters to explain them.
      Drews insists the evidence doesn't support Nur's theory. "If the place was suddenly destroyed, you'd expect to find all the things in the palace buried in debris, and we don't," he says. While archaeological digs have yielded some pottery, there are no beautiful treasures like ivory or gold, Drews says. Drews cites the small numbers of casualties as further proof against the earthquake theory. "We'd expect quakes to trap people suddenly, but we don't see evidence of that," he says. Though archaeologists have found some crushed skeletons, Drews believes an earthquake-destroyed city would have widespread casualties. But Nur offers a simple explanation, "When we have an earthquake nowadays, we dig through the rubble, find the victims and bury them." He says there's no reason to believe things were different then.
      Cline says the problem's crux is that it's difficult to differentiate between earthquake damage and human inflicted destruction. Both warfare and earthquakes can topple walls, start fires, and leave skeletons in the rubble. Even at sites where earthquakes are clearly implicated, there's no easy way to tell if the quake happened a hundred or a thousand years ago. "You can't deny there were earthquakes, that's a given, but the question is, what role did they play?" Cline says. "What I adhere to is the 'systems collapse' (model): the civilization as we know it comes to an end, but it's not from one cause, but from a series of events and factors. It was almost a domino effect, one domino may have been earthquakes."

WRITTEN TEXTS document mass migrations that dispersed the population among places previously sparsely populated. Reasons for these migrations aren't clear, but Cline believes this mass exodus could have been a large reason for the cities' demises. Archaeologists know that international trade was suddenly cut off during this period and Cline concedes that earthquakes could have been responsible. Yet another domino could have been drought, Cline says.
      Meanwhile, Drews proposes that warfare destroyed the Middle Eastern cities. He says invaders came from the Mediterranean Sea region and ransacked the Middle Eastern civilizations. These invaders set out with one purpose-to sack and loot, not to conquer, Drews says. "These days when rioters loot cities, they don't try and take over the store. If they're going to loot, they loot," he says. Drews believes the invaders came from regions where people were poor, and their motive was wealth. Once one group proved invading the Middle Eastern region paid off, the idea spread, Drews contends. "Somebody thought of it and it worked. Just like in modern times when someone tried hijacking a plane and once it worked the idea spread," Drews says.
      But Nur contends earthquakes were the dominant force in these civilizations' downfall, wars in the region were only possible because of the quakes, he argues. "These cities were run by a small elite. There was continual conflict between the elite and the poor people living in the countryside," he says. He concedes that his tone on this issue has evolved. Initially, when he was saying that earthquakes caused the end of the Bronze Age, "I didn't have it clear in my mind how they (quakes) did it. Now I've thought it through and I realize that earthquakes create a mechanism for the powerful elite to lose control."
      However, Drews takes issue with Nur's peasant uprising theory, "Villagers living in the vicinity of the center depended on those centers and would be the first to give aid. Nur seems to think these people were controlled by despot rulers and that's simply not the way it was."

SO WHY is the earthquake theory gaining attention now?
     "Before last year, when Nur's Biblical Archaeology Review paper came out, no one had heard of him. Nur simply wasn't reaching us (archaeologists) before," Cline says. But he also has another theory. "The new interest may be because of the coming millenium, hence the interest in Armageddon," Cline says.
      The newfound attention has helped Nur's cause. Last July, a meeting at Cambridge University brought together experts from a broad range of disciplines including archaeology, geology, and astronomy, to discuss the roles natural catastrophes could have played in the ending of Bronze Age civilizations. At the Cambridge conference, Nur told the audience about a gathering in Athens in 1991 where geologists and archaeologists discussed earthquakes in archaeology together for the first time. "When we (geologists) gave talks, the archaeologists would drink coffee outside, and when they gave talks we would drink coffee. So communication was not good. We didn't understand what they were talking about, and they didn't believe what we were saying."
      But that tension is waning. A book, "Archaeoseismology" (edited by geologist S. Stiros), which came out of the 1991 meeting between geologists and archaeologists has made more ancient scholars aware of the emerging field. Cline believes Nur's theory warrants serious consideration, and he's currently collaborating with Nur on a scholarly paper about the earthquake theory. They hope their paper will give the battered hypothesis serious attention.
      Although he doesn't believe earthquakes are the entire story, Cline believes Nur's expertise can contribute to archaeology. "Nur is a specialist in tectonics, he's familiar with rock formations and he might be able to look at a site and see evidence archaeologists can't. Archaeology frequently borrows from other sciences, this could allow archaeology to tap into geophysics."