Nonsense of Noah
|National Geographic, July 2000 v198 i1 p52
A HISTORY FORGED BY DISASTER.
This article documents the fact that the area around Mt Ararat is on a serious fault, the "North Anatolian Fault", and has suffered from earthquakes for centuries. "The Gods" were blamed for all natural catastrophes including the flood that created the Black Sea 7500 years ago.
Full Text: COPYRIGHT 2000 National Geographic Society
CROSSROADS of both peoples and tectonic plates, the Anatolian region is rich with stories of cultures accommodating themselves to a violent geologic landscape. Near the modern city of Van in eastern Turkey, remmants of an Ottoman castle cover the ruins of fortresses as old as the ninth century B.C. Strategically set on a hill created by colliding plates, the castle overlooks the Middle East's second largest lake, 75-mile-long Lake Van, formed when a volcanic eruption blocked rivers' flow.
HEARTACHE HAS FOLLOWED ME from the rubble piles along the Sea of Marmara to a bleak and rocky landscape in eastern Turkey. Gecmis olsun--"May it be over." I've said that phrase so many times to survivors of the killing earthquakes near Istanbul. But, in fact, I know what no one wants to hear: It will never be over. Nowhere have civilization and nature waged more persistent war than in this part of the world--from easternmost Turkey to the western tip of Greece.
In the first century B.C. a self-absorbed king named Antiochus I, ruler of the ancient land of Commagene, built an audacious tomb and monument to himself on top of a 7,000-foot-high mountain called Nemrud Dagh. There, he proclaimed, his mausoleum would be "unravaged by the outrages of time."
He constructed a conical tumulus more than 200 feet high from fist-size rocks, hauled up and assembled with unimaginable labor. On terraces around the tumulus stood a pantheon of colossal statues--gods and heroes with whom he expected to consort in the afterlife.
No doubt Antiochus's understanding of geology was as flawed as that of the driver who is now transporting me in his dolmus from the Turkish town of Kahta to Nemrud Dagh. Gesturing toward a cluster of oil wells on the rocky landscape, the driver declares: "That's why we have earthquakes. They are pumping out the oil and the land collapses."
I nod, knowing I could never convince him how little power human actions have over the titanic forces of the Earth--even with the abundant evidence I find a few hours later at the pinnacle of Nemrud. The tumulus has shrunk to 150 feet as rocks have tumbled down the mountain. And someday--an instant from now in geologic time--the king's tomb will be gone, his coffin laid bare by the ravaging tremors he thought he had risen above. I pause before great stone heads of Zeus, Heracles, Apollo--and of the vainglorious king himself. All these constructs of human imagination are laced with cracks or toppled on their sides. Surrounding me are the constructs of geology, the real ruler of this land--limestone and shale that formed at the bottom of a deep marine basin and that, over time, were pushed up into mountain ranges. Even Antiochus's statues were carved from uplifted limestone.
Humans in this part of the world have long blamed the Earth's sudden and violent changes on supernatural agents. In 464 B.C., when an earthquake destroyed Sparta and provoked an uprising of serfs, the ancient Greeks blamed Poseidon, the earth shaker. And just last year, after an earthquake devastated suburbs of Athens, a priest at the monastery of St. Kyprianos told me the catastrophe was a divine warning: "It was sent to shake us from our sins."
Rob Reilinger, a geophysicist at MIT, provides the scientific explanation--"There's a full-scale continental collision going on," he says, "where Africa and Arabia are driving north and colliding with Eurasia." That collision, which has continued over the past five million years, creates a complex pattern of geologic processes that fascinate scientists just as they mystified and devastated ancient cultures.
The collision began in eastern Turkey and affects most of Anatolia, the peninsular part of the country. Arabia, which is moving north slightly faster than Africa, hit first, and when it shoved into the underbelly of Eurasia, it thrust up not only Nemrud Dagh but also the Caucasus Mountains.
The collision has thickened the continental crust in eastern Turkey, now about 30 miles thick, compared with some 25 miles thick farther west near Ankara. As a result the region, which lay near sea level before the collision, is now a plateau averaging more than a mile high. In some places jagged remnants of ancient seafloors that once lay between the colliding continents jut from the compressed landscape as mountains. Most of the rock in those seafloors, however, was pressed down toward Earth's mantle. This stimulated melting and the formation of magma that resurfaced through cracks to form volcanoes such as Mount Ararat, the fabled final resting place of Noah's ark.
Almost 17,000 feet high, Ararat, flanked by its smaller sister, Little Ararat, dominates vistas along the Turkish-Iranian border. No wonder the ancients believed that this ice-crowned massif would be the first land to emerge from a great flood. But today the legends that have surrounded the mountain are forgotten by residents of Dogubayazit, the nearest town--charmless, commercial, and ravaged by years of Turkish-Kurdish conflict.
"People in the town don't know anything," says a local hotelier, Feyyaz Salman. "But my 110-year-old grandmother, who lives in a nearby village, told me the two mountains were sisters who hated each other. Little Ararat cursed her big sister, saying `May you grow so tall you will always have snow on your head.' In turn, Big Ararat cursed her little sister: `May you always be so close I can control you. And may you always have snakes in your hair.'"
Neither volcano has erupted in recent memory, but residents of eastern Turkey have much to fear from earthquakes. The compression resulting from Arabia's northward thrust is pushing Turkey westward in jolts, like fingers squeezing the pit from a cherry.
No city in Turkey has suffered more pain from earthquakes over the centuries than the ancient metropolis of Antioch. In A.D. 115 the Emperor Trajan blamed an earthquake that destroyed the city on the presence of Christians and had the bishop, Ignatius, thrown to the lions. Walls fell again in A.D. 458. In 526 an earthquake killed 300,000 people, according to the historian Procopius. His figures are exaggerated, but other crushing earthquakes occurred the same year. Plague hit in 542, Persian armies in 573. Another earthquake in 588 closed a devastating century.
Modern Antakya, on the site of the ancient city, still falls victim to frequent earthquakes. A third of Antakya was leveled in 1872. Geologists know that the city lies near the junction of three major faults, including one slicing up from the Dead Sea. So why do people continue to rebuild here? It's a crossroads, say some. The climate is mild and the soil is rich, say others. "We've always lived with risk," adds businessman Joseph Naseh. "If it wasn't earthquakes, it was invasions."
Indeed, invasions have been almost as common as earthquakes in Anatolia. And ironically, violent Earth forces have actually helped people in the heart of Turkey protect themselves against raiding armies. In a region called Cappadocia fiery surges of volcanic ash, cooled and sculpted by erosion over the past few million years, have covered the ground with blankets of rock so soft that humans could cut sanctuaries--even entire secret cities--into them when faced with invading hordes.
"Cappadocia coming up!" says Lars-Eric More, pilot of a hot-air balloon that has lifted me and a basketful of sightseers over a vista of mushroom-shaped rocks with doors and windows. Farther on we float above a canyon forested with pinnacles and spires of stone in shades of pink, white, ocher, brown, and gray. Then cliffs with churches carved into them by Byzantine monks. Here humans and the forces of geology have coexisted harmoniously and spiritually.
The volcanic avalanches of Cappadocia were generated, like almost every geologic event in the region, as Africa drew closer to Anatolia. Dense oceanic rock in front of the approaching continent subducted beneath Turkey, and as the water-rich rock dived deeper and mixed with the mantle, it created the particularly gaseous magma that exploded across Cappadocia.
Although geologists believe that epoch of volcanism has ended, the subducting of seafloor continues to the west beneath the Aegean Sea. The diving seafloor there exerts a powerful tug, pulling the Aegean crust toward Africa. That tug has stretched and thinned the Aegean, turning what once was dry land into a drowned continent. It is also opening a space into which Anatolia can move as it's being squeezed by Arabia in the east.
Much of Anatolia's westward movement occurs along a particularly dangerous geologic feature known as the North Anatolian Fault. That fault, which separates Anatolia from the rest of Eurasia, runs east to west just south of the Black Sea. About 75 miles before it reaches the Sea of Marmara, the fault forks into at least two strands. The sea, which reaches depths of more than 4,000 feet, is actually a rift, pulled apart by tension between the strands, which continue westward across the Aegean to Greece.
In the Marmara area the North Anatolian Fault has caused immeasurable devastation. In the past 2,000 years almost 600 documented earthquakes--40 of them magnitude 7 or greater--have hammered the region. Izmit has been destroyed repeatedly, and Istanbul itself has been severely damaged four times by great earthquakes in the past 500 years.
The fault may also have triggered the most catastrophic event ever seen along the Sea of Marmara--an enormous flood about 7,500 years ago that filled up the Black Sea Basin--according to Bill Ryan and Walter Pitman, geologists at Columbia University. They recently demonstrated that at the end of the Ice Age the Black Sea was much lower and smaller. Then as glaciers melted, rising seas cut a channel--today's Bosporus--from the Sea of Marmara toward the Black Sea Basin. Perhaps triggered by an earthquake, an enormous flume of water poured down an escarpment north of modern Istanbul for more than a hundred days, filling the basin to sea level. The flood must have driven settlers all along the former coast from their villages. Perhaps, Ryan and Pitman suggest, it was this sequence of events that inspired the story of Noah's Flood.
ON A RAINY, blustery day I head up the Bosporus to visit the spot where the fabled strait widens into the Black Sea--the presumed site of the breakthrough. The waters of the strait grow rough where the Mediterranean once cascaded. I watch waves toss fishing boats bringing in their hauls of mackerel, bluefish, and bonito--and the angry waters still seem to echo the prehistoric turmoil of the flood. No wonder the ancients feared this passage. In Greek mythology the headlands on either side of the Bosporus were great rocks that crashed continually against each other, preventing ships from sailing through to the Black Sea. Not until courageous Jason and the Argonauts passed safely through did the rocks cease their clashing forever.
The North Anatolian Fault played a role in the formation of another Turkish strait, the 38-mile-long Dardanelles, which connects the Sea of Marmara with the Aegean. I drive along the Gallipoli Peninsula, watching the ships of many nations steam toward old Byzantium in the late afternoon sun. Few places evoke such human history. Here in 480 B.C. the Persian King Xerxes built a bridge of boats to stage an abortive invasion of ancient Greece. Alexander the Great crossed back over in 334 B.C. en route to conquering the world. Attempts to control the Dardanelles sparked desperate battles between the Turks and Allies in World War I.
Myth touches the Dardanelles too--in a tale of ancient Troy, which guarded the entrance to the Dardanelles throughout the Bronze Age. In Homer's Odyssey, the Greek hero Odysseus devised a trick that ended the Trojan War. Greek soldiers hid within a great wooden horse, which the Trojans unsuspectingly took within their city walls. I stand in front of one of those walls with Manfred Korfmann, an archaeologist at the University of Tubingen. Korfmann explains another theory about the Trojan horse.
"See those cracks?" says Korfmann, pointing to the heavy gray stones of the tower. "Most people regard them as earthquake cracks." Korfmann suspects that over several centuries the Greeks fought many skirmishes with Troy because Troy controlled access to sources of metal around the Black Sea. He believes that at some point an earthquake may have brought down Troy's walls, letting the Greeks in. To celebrate their victory, the Greeks may well have erected a horse to thank Poseidon for the quake--the horse being a symbol of Poseidon.
Two particularly devastating earthquakes around A.D. 500 demolished Troy once and for all. In fact, an unparalleled wave of big earthquakes from the mid-fourth to the mid-sixth centuries hit all the major cities of southwestern Turkey: Pergamum, Aphrodisias, Ephesus, Smyrna. This puzzling sequence, called the early Byzantine tectonic paroxysm, may reflect a huge shifting of plates from Palestine to Crete. "It was not a good time to be alive," says Brian Rose, an archaeologist at the University of Cincinnati. "The earthquakes kept coming."
The force that gives rise to most of the earthquakes that plague the Aegean region of Turkey is called extension. As the subducting African plate stretches and thins the crust, great cracks known as grabens open up. The grabens become valleys that fill with fertile sediments.
Extension in the Aegean has enriched the soil of southwestern Turkey. But the same process, occurring too rapidly and accompanied by centuries of deforestation, has encouraged the buildup of too much silt in places, turning waterways into swamps and until recently encouraging the spread of malaria.
With Ilhan Kayan, a geographer at Aegean University, I visit the Little Meander Valley south of Izmir. As we look out over the farmland, Ilan explains how heavily the silt has accumulated in some parts of the region: "The sediments are 88 feet deep in the center of this valley," he says. "If you could take a big vacuum cleaner and suck them all up, the sea would flow in here."
Both earthquakes and the steady buildup of silt made life difficult for the residents of Ephesus, the best preserved of the ancient cities in the region, Ilhan takes me to a hill overlooking the site of the Temple of Artemis, constructed to the goddess of the hunt in the sixth century B.C.
"They probably built that great temple on the coast,' says ilhan. Today I can barely see the Aegean; the encroachment of silt has shifted the shoreline five miles to the west. Being stranded so far inland destroyed the economic viability of Ephesus. That and Christians having no desire to maintain a city filled with pagan monuments. Still, the huge marble temple that once stood below us, built to honor the Greek goddess, was one of humanity's greatest achievements--and one of the seven wonders of the ancient world.
ALONG TURKEY'S southern coast the process of extension has caused land on the shore to drop into the Mediterranean. At the town of Ucagiz I hire a boat to sail across a bay that once did not exist. "Scientists tell us there is a Roman amphitheater below us," says the captain, Ibrahim Turan. We cross to an island named Kekova, once a Byzantine city, that is sinking into the sea. We cruise past the subsiding buildings that line the shore. Beneath the boat lie the foundations of houses.
At the same time Kekova is dropping into the water, land across the Aegean in Greece is rising rapidly. Stathis Stiros, a geologist at the University of Patras, takes me along the south coast of the Gulf of Corinth, a dramatic waterway separating the Greek mainland from the Peloponnesian peninsula. On the eastern shore of the gulf we stand on cut rocks that, around 500 B.C., were laid underwater to build a harbor at Corinth, a wealthy city renowned for its elegant pottery. Stiros points out holes that were drilled in the rocks by marine animals.
"Those holes were made underwater," he says. "Now they are nearly four feet above the shoreline."
The entire southern coast along the gulf is rising. Stiros takes me farther west to a rocky terrace where corals that lived some 30 feet underwater 10,000 years ago now stand about 20 feet above it. In the mountains that plunge to the coast we wander through the ruins of the city of Aigeira, nearly a thousand feet above sea level. About 120,000 years ago, says Stiros, we'd have been at sea level.
Basically the Gulf of Corinth is a deepening graben. The Peloponnesus was pulled away from the mainland by the same extension forces that stretch western Anatolia and the Aegean. But, more important, the same land is also being squeezed by a familiar culprit.
"All of central Greece is now caught up by the North Anatolian Fault," says Rolando Armijo, a geologist at the Institut de Physique du Globe in Paris. "The northern branch is driving up mountains, including Mount Olympus. The southern branch is arriving about 60 miles to the south. The Gulf of Corinth and Athens are on the front edge. The land around it is cracking as the fault approaches. We call it the damage zone."
On September 7, 1999, Athenians were surprised to learn they lived in such a place--even though the Parthenon bears cracks from earthquakes in past centuries. On that day a magnitude 5.9 quake shook Athens for 15 seconds, killing 143 people and leaving more than 50,000 homeless.
Earthquakes have struck far more frequently to the southwest of Athens in the Peloponnesus, devastating some of the great cities of ancient Greece. "There's been a lot of bloodshed here," says Iphiyenia Tournavitou, an archaeologist at the citadel of Mycenae. In mythic Greek tragedy these brooding ruins witnessed horrific human catastrophe. Here Clytemnestra murdered Agamemnon for sacrificing their daughter Iphigenia to the gods, and Orestes slew his mother for killing his father.
From this strategic palace on top of a steep hill, the elite families of Mycenae became one of the great powers of the Greek world in the 14th and 13th centuries B.C. Yet the walls of their citadel, it turned out, were as vulnerable to forces in the Earth as its rulers were to human passions.
Mycenae, like all the great citadels of the region, has suffered many earthquakes over time. "In 1250 B.C. the city experienced major destruction," says Tournavitou. "We find people crushed beneath the walls of their houses." But the citadel was quickly rebuilt and extended. Fifty years later a bigger disaster hit Mycenae. "They never quite recovered. The ruling aristocracy must have collapsed."
Invading raiders disrupting trade in the Mediterranean probably undermined the Mycenaean economy. But increasingly archaeologists see earthquakes as opening the doors to destruction, much as they might have knocked down the walls of Troy, letting in the Greeks. Most agree that earthquakes, and especially a titanic volcanic eruption around 1600 B.C. on the island of Thera, led to the decline of the powerful Minoan culture on the nearby island of Crete.
Floyd McCoy and Grant Heiken, scientists financed by grants from the National Geographic Society, have studied the Thera eruption--one of the largest in history. A smaller first eruption, which put down a dusting of ash before the main event, may have scared most of the people away--excavations have revealed no skeletons.
The second eruption began with a blanket of light pumice that buried the town of Akrotiri, downslope, many feet deep. Then seawater entered the vent of the collapsing volcano and explosively mixed with magma and gases. The enormous amount of steam generated by the water made an already violent eruption ultraexplosive, McCoy explains, "the worst kind of eruption we can get on this planet."
Thera's ash and pumice snowed down on Crete, 70 miles to the south. Tsunamis battered its north coast, perhaps sinking many Minoan ships--disaster for a seafaring culture. The ash likely destroyed crops along with the grasses that fed livestock.
This was not the first geologic catastrophe on Crete. "At least a century earlier a great earthquake destroyed the palace at Knossos, the center of Minoan power," says Eleni Hatzaki, curator at Knossos for the British School at Athens. "The Minoans rebuilt on a grand scale, and the peak of their culture followed." But another major quake seriously damaged the palace around the same time as the eruption on Thera. In the decades that followed, all the major palaces on Crete were destroyed by fire--probably set by invaders--and eventually Mycenaean Greeks took control of the island.
Earthquakes continue to ravage Crete as Africa, only 200 miles to the south, approaches. As the eastern part of the island sinks, the western part is rising dramatically. Dating the shells of marine animals that live at sea level, geographer Paolo Pirazzoli of the French Research Council finds evidence for an astounding uplift of 27 feet in one great earthquake. He thinks it occurred on July 21, A.D. 365, the date of a huge Mediterranean tsunami.
On the far west coast of Crete that incredible upthrust pushed a Hellenistic harbor named Falasarna about 20 feet above sea level. On the last day of my journey I climb the mountain behind the town. Its slope is littered with blocks cut from nearby cliffs and hauled here long ago to build foundations. The climb is strenuous, and I grow sad. So much energy went into this town, now nothing but ruins.
A blast of wind nearly knocks me off my feet. I imagine myself lashed by Poseidon's breath. No. I'm just exhausted by this journey and feeling small and powerless in the face of all the forces the earth shaker represents. I remember what I saw after the Izmit earthquake and wonder why so many people had to die. Are all our labors futile?
Another gust, and I remember Adapazari, near the epicenter of the Izmit earthquake--I visited there three months after so much of it had collapsed. New buildings were already going up. The muddy streets throbbed with life. Even though many residents were living in tents, energy was returning. A sticker on the back window of a car read: "I love my Adapazari and I'm not deserting it."
On that windswept mountain it occurs to me that humans are not so powerless after all. We are durable. We possess the cleverness of Odysseus, the sublimeness of Homer, even the vanity of Antiochus. We are fired by the forces of imagination and love and by the ability to cry over our tragedies and, above all, to envision a new day. That's what keeps us even with the earth shaker. We bounce back--and cloak the worst that nature can do to us with the grace of our humanity.
THE CRADLE HAS ROCKED
Like the fire-breathing Chimera of Greek mythology--part lion, part goat, part serpent--the area now bounded by Greece and Turkey is a mosaic of incongruous parts that come together fearsomely. Trapped between three huge, converging continental plates, the Anatolian and Aegean regions have been roaring and breathing fire for millions of years--and terrorizing humanity for millennia. "It is an exceptional place: You have extreme geologic activity--with frequent earthquakes and volcanic eruptions--in one of the cradles of Western civilization," says earthquake geologist James Dolan.
Where oceanic plates meet continental plates, the denser ocean plate pushes beneath the continental plate, and magma rises to create volcanoes.
As crust is stretched by subduction, faults can caused its to rise or fall. On land and in the sea, valleys called grabens form and fill with sediment.
When two continental plates collide head-on, they may push crust upward, forming mountain ranges. Such a collision formed eastern Turkey's mountains.
Plates moving past each other horizontally lock together until tension builds to a release point--an earthquake. Quakes range from barely detectable to cataclysmic.
VOLCANOES AND EARTHQUAKES IN HISTORY AND MYTH
We have known about plate tectonics for only about 40 years. Before that our imaginations--scientific or otherwise--had to make sense of the Earth's geologic forces, Like countless cultures, the ancient Greeks and Romans personified the power of natural forces in a pantheon of gods. Hephaestus--whom the Romans called Vulcan, the namesake of volcanism--was the god of fire and volcanoes, Poseidon the god of earthquakes as well as the sea.
IT'S ANATOLIA'S FAULT, BUT ARABIA AND AFRICA ARE TO BLAME
Imagine the Anatolian plate as a slippery seed between a finger and a thumb--the Eurasian and Arabian plates. As the Arabian plate moves northward into the Eurasian plate, it squeezes the Anatolian plate westward, causing earthquakes along the North An atolian Fault. Farther west, the African plate is pushing beneath the Anatolian plate, stretching the Aegean Sea's underlying crust and allowing magma to rise to the surface through volcanoes.
A STRAIT'S SHAKEN GLORY
It takes either a sturdy boat or a kilometer of bridge to cross the Bosporus today, but people may have walked cattle across the Bosporus--which means "ox ford"--before Mediterranean seawater started spilling through the strait into the Black Sea Basin some 7,500 years ago (see "Black Sea Flood," page 71). It is possible that an earthquake caused the rupture that opened the strait. Istanbul, perched on the banks of the Bosporus, has weathered dozens of major earthquakes in the 1,700 years since Roman Emperor Constantine made it the empire's new capital. Adding to Constantinople's glory, in 537 Emperor Justinian inaugurated a domed cathedral then unparalleled--Hagia Sophia, or Holy Wisdom (above, dome at left). "Solomon, I have outdone you!" legend says he declared. It only took 20 years for an earthquake to inflict serious damage. The building still stands, many quakes and repairs later, buttressed along the way for stability (top).
A mid-16th-century woodcut (above) depicts an earthquake's aftermath in Constantinople. Unsettling apparitions in an orderly sky, comets throughout history have embodied cultures' worst fears; this one was taken as an omen of the quake.
THE GODDESS APHRODITE flanks the handiwork of her sometime lover Hephaestus, god of volcanoes. In a blast 90 times that of Mount St. Helens, the center of Thera collapsed into a sea-filled caldera, where a new cone slowly builds. Some call this the source of Plato's story of the lost continent Atlantis.
WRATH OF THE GODS BLACK SEA FLOOD
NEW EVIDENCE OF CATACLYSMIC CHANGE
Once upon a time, when people wanted to find evidence of the biblical Flood, they searched the flanks of Mount Ararat for remnants of Noah's ark. Now scientists are finding mounting evidence that there may have been a calamitous flood of the Black Sea about 7,500 years ago--close enough to historical times to give rise to an ancient flood myth.
As the last ice age was waning 12,000 years ago, the Black Sea was a smaller, freshwater lake. As glaciers melted over the following millennia, global sea levels rose gradually but markedly; it was thought that the Black Sea's level did likewise. Now it appears that a natural dam at today's Bosporus may have held the rising Sea of Marmara at bay--until the dam's collapse sent ten cubic miles of seawater a day roaring into the Black Sea, then 500 feet lower. The sea would have pushed inland up to a mile each day for months, forcing inhabitants to flee. This is the theory of marine geologists William Ryan and Walter Pitman, who in 1993 found a sediment and marine-life record off the sea's north shore suggesting such a flood. Corroborating that theory, last summer ocean explorer Bob Ballard found a beach beneath 500 feet of water near the sea's south shore. The sediments yielded lakeshore rocks and shells--freshwater shells as young as 7,800 years old and saltwater shells as old as 7,300 years--indicating the freshwater lake had been inundated by salt water. Buoyed by the find, Ballard plans to search for evidence of human settlement along the drowned shore.
For more about Bob Ballard's exploration go to www.national geographic.com/blacksea.
Document Number: A63604345