"When the earth quakes, all hell breaks loose." "They strike with lightening speed" " a huge bolt of destruction." "These forces baffle experts" "Who are on a desperate mission to predict when and where" "The next big one will hit." "jack boatright: with each earthquake you ha?" "e things that" "You didn't predict before" "We'll circle the globe," "Examining significant earthquakes of our time " "Each more powerful than the last," "Each with its own c?" "mpelling mysteries," "Each propellng us towards a projected mega disaster " "?" "monster quake that could rock our world." "Earthquakes are one of the most destructive" "?" "nd unpredictable forces on the planet." "With?" "ut warning, s?" "lid gr?" "und cracks," "Shifts and buckles," "Threatening anything in its path." "It's estimated that several million earthquakes" "Shake the planet every year..." "Most are barely detectable tremors." "?" "ut at least once a year, somewhere on the globe," "?" "major e?" "ent strikes." "Most earthquakes are created by mo?" "ements of titanic slabs" "Of the earth's crust, called tectonic plates." "Enormous pressure builds as the plates strain against each other." "When plates slide past each other," "?" "strike-slip earthquake forms." "When plates collide head on and one slides under the other," "?" "thrust earthquake occurs." "In both cases the earth's crust tears and snaps," "Releasing a giant burst of seismic force." "The amount of energy released by" "?" "n earthquake is kn?" "wn as its magnitude." "The higher the magnitude, the more energy released." "?" "n earthquake of magnitude 8 ?" "r higher" "Releases as much energy as a billion tons of tnt," "Or 67,000 hir?" "shima bombs." "Earthquake's destructive energy" "?" "as caused almost 8 million lives in the last 1 000 years." "The fatality rate is rising as populations" "In high risk areas increases dramatically." "Don windeler: it's kind of an ine?" "itable shift" "?" "s people cluster more and more," "The larger cities continue to grow larger and larger." "Today there are 1 7 cities jammed with more than 1 0 milli?" "n people." "140 other metropolitan areas" "?" "a?" "e populations topping two million." "More than half of these are" "Within striking distance of a major fault line - placing hundreds of milli?" "ns directly in the line of fire." "Don windeler: a lot of times we're our own w?" "rst enemies" "In terms of where we build and how we build these cities." "It's only a matter of time before another city is hit" "?" "y a de?" "astating earthquake." "To prepare f?" "r the inevitable future," "It's essential to Iearn from the past... ." "Loma prieta 1 7-Oct-89" "Magnitude: 6.9" "Type: strike-slip" "?" "ey fact?" "rs:" "liquefaction, seismic reflection" "October 1 7, 1 989," "San francisc?" ", calif?" "rnia." "For 1 5 horrific seconds," "The city by the bay is rocked by a magnitude 6.9 earthquake." "The epicentre is near a m?" "untain in santa clara c?" "unty" "Called loma prieta." "Suburbs cl?" "se to the m?" "untain suffer serious damage." "The ground splits open in huge gashes," "?" "undreds of homes are thrown off their foundations," "?" "nd small communities are ripped apart." "But bizarrely, the greatest de?" "astati?" "n and loss of life" "Is 97 kilometers (60 miles) to the n?" "rth " "In ?" "akland and san francisco." "The quake brings down a section" "Of oakland's cyprus expressway," "Turning a busy freeway into a gra?" "eyard." "Oakland firefighter lorenz?" "frediani is" "One of the first to respond." "Lorenzo frediani: ... itwasahorriblescene." "It was such a large scale disaster" "Seeing huge pieces of the freeway ?" "n top of cars," "Fires beginning to erupt, everyone just yelling and screaming f?" "r help." "Frediani and other rescuers race to find survi?" "ors." "They fear the worst " "That th?" "usands are dead under the shattered remains" "Of the expressway." "Frediani: this was at 5 o'clock appr?" "ximately this was its peak time." "There should be bumper to bumper traffic" "So when i saw the cyprus unfold in front of me" "?" "ll i c?" "uld think about was how many thousands of people would be dead" "?" "ut amidst the h?" "rror there is a life sa?" "ing stroke of luck." "?" "he earthquake hit as the two local baseball teams " "The san francicso giants and the oakland athletics " "Faced off in the world series." "Millions are watching the game" "?" "nd traffic is much lighter than usual." "Frediani: the fact that we had a ball game" "?" "etween the two bay area teams" "Easily saved a thousand lives." "?" "s rescuers desperately try t?" "free those" "Trapped on the cyprus expressway," "?" "nother disaster unf?" "lds across the bay." "Nearly 200 buildings in the marina district" "?" "re se?" "erely damaged" "Or completely destroyed." "Fires started by broken gas mains" "?" "dd to the damage and panic." "Stunned residents flee into the streets." "?" "ut even as the marina suffers catastrophic damage," "Neighbourho?" "ds surrounding it escape almost unscathed." "Seismologists like jack boatright" "Struggle to understand the quake's selecti?" "e destructi?" "n." "jack boatright: the ground m?" "tion and damage in the marina" "Was a surprise, not just to the lay pe?" "ple," "It was also a surprise t?" "seismologists." "The earthquake seemed to defy logic " "It targeted two specific areas, 97 kilometers (60 miles) from the epicentre," "Leaving most of the bay area untouched." "?" "oatright and his colleagues" "Set out t?" "solve this mystery by going back t?" "basics." "When a fault ruptures," "Spherical waves of energy are released," "Tra?" "elling through the gr?" "und until they reach the surface." "Like any other kind of wa?" "e, they can bend," "Reflect, or join together to make bigger wa?" "es." "Oakland and the marina district" "Were unlucky enough to be hit by a seismic double-team " "Two sets of wa?" "es that joined together." "One set travelled directly from" "The earthquake's centre to the surface." "?" "nother travelled deep into the earth" "Then b?" "unced off the boundary" "?" "etween the solid crust and the m?" "lten layer beneath it." "The reflected wa?" "es reached the surface 97 kilometers (60 miles)" "Away from their s?" "urce " "Directly under oakland and the marina district." "This seismic double whammy was bad en?" "ugh" "?" "ut it became much w?" "rse when combined" "With a fatal mistake made by the city's forefathers." "?" "hundred years ago, this land didn't exist." "?" "s the bay area rapidly expanded," "Stretches of ocean became beachfront property." "The shallow edges of the bay were filled in with sand and debris." "jack boatwright: the difficulty is," "With these ?" "ery fine and clean sands," "When an earthquake occurs and you start shaking them" "There's really nothing binding the sand together." "It becomes actually a liquid" "Liquefaction is a deadly side effect of" "Many large earthquakes." "?" "s solid ground turns t?" "liquid," "Roads are destroyed, buildings topple," "?" "nd underground pipes rupture." "Liquefaction se?" "ered a gas main in the marina," "Igniting an inferno." "The total cost of the quake was huge." "Sixty-three people died, four th?" "usand were injured," "?" "nd twenty thousand structures were damaged or destroyed." "For seism?" "logists," "The 6.9 Ioma prieta quake was a brutal wake up call." "They were surprised by the reflection" "Of seismic waves that struck the marina district and oakland." "jack boatwright: with each earthquake" "You ha?" "e things that you didn't predict before." "every earthquake is in fact a learning experience." "?" "ut the 1 989 loma prieta quake was n?" "t" "The worst to strike san francisco." "The same side effects of liquefaction" "?" "nd fire killed th?" "usands when a much bigger earthquake struck," "Destroying most of the city by the bay." "San francisco" "?" "pril 1 8, 1 906," "Magnitude: 7.9" "Type: strike-slip" "?" "ey fact?" "rs:" "liquefaction, fire" "Mary-lou zoback:" "around the turn of the century san francisc?" "Was actually the premiere city on the west coast of the united states." "The city featured luxury h?" "tels" "?" "nd modern high rise buildings." "?" "ut in 1 906, many came crashing d?" "wn." "Mary lou z?" "back:" "the earthquake occurred about 5:1 2" "In the morning of april 1 8th, and when it occurred" "It essentially occurred without warning." "?" "loud roar jolted thousands out of their beds." "Seconds later, a giant sh?" "ckwave hit the city," "Shaking buildings to their foundations." "The west coast's econ?" "mic" "?" "nd architectural center lay in ruins." "?" "t the time, seismol?" "gy was in its infancy," "?" "nd the quake's cause was not well understood." "We now know the city was caught" "In the middle of an ancient battle" "Between the pacific and north american tectonic plates " "?" "n infamous warzone called the san andreas fault." "These mighty slabs of crust are scraping past" "Each other directly beneath san francisc?" "." "When sections become locked together," "Enormous pressure builds up," "?" "nd is released as a strike-slip earthquake." "In 1 906, 435 kilomteres (270 miles) of the fault ruptured." "?" "magnitude 7.8 quake released eight times" "More energy than the 1 989 event." "The first and fastest wa?" "es released" "?" "y any earthquake are primary, or "p" wa?" "es." "They act like a sonic b?" "om " "Shaking the gr?" "und and rattling windows." "?" "few seconds behind are the secondary, ?" "r "s" wa?" "es." "These carry most of the earthquake's energy" "?" "nd are the most destructive kind of seismic wa?" "e." "In san francisco, the "s" waves tore huge gashes in the earth" "?" "nd ripped apart building foundations like paper." "?" "ut it's an?" "ther side-effect of the earthquake that" "Sealed the city's fate." "Liquefaction of the ground severed gas" "?" "nd water mains, and san francisco began to burn." "With?" "ut a water supply," "The fire department stood by helpless" "?" "s the city burnt t?" "the ground." "Mary-lou zoback: the descripti?" "ns of the fire" "?" "re they actually refer to this as a firest?" "rm" "?" "nd in a firestorm the heat is so intense" "That it actually sucks in air." "The fire raged for three days," "Incinerating ten square kilometers (f?" "ur square miles)," "Destroying more than 28,000 buildings" "?" "nd lea?" "ing a quarter of a million residents h?" "meless." "More than 3000 people were killed." "The 1 906 event pr?" "ved that a earthquake's complex" "Side effects can be more de?" "astating than the quake itself." "80 years later, a bigger earthquake crippled" "?" "city 45 times larger than san francisc?" "." "?" "he key culprits:" "a totally different seismic side effect" "Combined with disastr?" "us city planning." "?" "ut even that quake is dwarfed by a p?" "tential mega quake," "?" "n event of en?" "rmous power and c?" "nsequence." "The san francisc?" "earthquakes of 1 906 and 1 989" "Showed how reflection and liquefaction can" "?" "a?" "e tragic consequences." "In 1 985, one of the largest cities in the world" "Was crippled by an earthquake with e?" "en stranger" "?" "nd more unpredictable effects." "It pro?" "ed that where you build a city is as important" "?" "s h?" "w you build it." "Mexico city 1 9-Sep-85" "Magnitude: 8.0" "Type: subduction" "?" "ey fact?" "rs: amplification, resonance" "Mexic?" "city is one of the world's largest cities" "With a current population of more than 20 million." "The metr?" "p?" "lis sprawls across a mountain ?" "alley" "In the centre of mexico." "It's a city of non-stop acti?" "ity," "Its massive p?" "puIation busy day and night." "On september 1 9, 1 985, dawn breaks ?" "n a typical autumn morning" "Millions of people face the new day." "Suddenly the earth begins to writhe and buckle." "?" "magnitude 8 earthquake strikes the city." "The epicenter is off mexico's west coast." "It unleashes six times more destructi?" "e energy" "Than the 1 906 san francisco quake." "?" "undreds of multi-st?" "ried buildings disintegrate into rubble." "Thousands of ?" "thers are se?" "erely damaged." "Fernando (in spanish):" "I didn't know what was happening." "Your mind is racing a thousand mile per hour." "You d?" "n't know if you are already dead." "The city struggles to c?" "pe as phone" "?" "nd electricity lines are se?" "ered," "Emergency services o?" "erwhelmed," "?" "nd millions left to fend for themsel?" "es." "Three of the city's largest hospitals are severely damaged," "?" "dding to the chaos and casualties." "One of the most h?" "rrific scenes is at the nuevo leon," "?" "1 5-storey apartment building." "Of the 1 800 people Who li?" "ed here," "More than 600 were killed." "Cuauhtemoc avarca is a stunned witness" "As the nue?" "o leon falls ?" "ictim t?" "the earthquake's rage." "Cuauhtem?" "c a?" "arca:" "I recall it like a nightmare," "?" "ecause this huge structure," "So s?" "Iid for us," "In those moments, collapsing as if it was made of paper," "Like a model, like an in?" "isible hand was pushing down." "Cuauhtemoc and d?" "zens of his neighbours rush" "To the demolished apartment building" "?" "nd with their bare hands begin a desperate struggle" "To rescue survivors." "?" "here was a survi?" "or whose left side was trapped by debris..." "We couldn't m?" "ve the concrete abo?" "e him..." "It was s?" "so heavy." "I was holding the right hand of this man trying to encourage him..." "?" "e was c?" "mplaining this is so painful." "It hurts. ?" "nd..." "?" "e died." "The death toll is estimated" "?" "t anywhere between 9 and 35 thousand." "The true number may ne?" "er be known." "Why was this mighty city ?" "ictim to such de?" "astation?" "Mexic?" "city is in the centre of the country," "?" "undreds of kilometers (miles) away from" "The earthquake's epicenter." "?" "nd why were some areas practically annihilated" "While others were left untouched?" "For seismologists like cinna lomnitz," "This disaster would change their understanding of seismic wa?" "es." "Cinna lomnitz:" "there were many surprising factors that" "Intervened to cause this earthquake to be a disaster" "The quake was triggered by mo?" "ements of the cocos plate," "Which collides with the north american plate" "Off mexico's west coast." "unlike the san andreas fault where tw?" "plates" "?" "re sliding past each other," "Mexico is the scene of a tectonic head-on collision" "Called a subduction zone." "Normally, one plate slides smoothly under the other." "?" "ut when a section bec?" "mes stuck," "Enormous pressure builds up in the rock." "On that fateful morning," "The pressure finally becomes too much." "?" "secti?" "n of the cocos subducti?" "n zone rips apart," "?" "Iasting a massive shockwa?" "e of seismic energy" "?" "owards mexico at thousands of kilometers (miles) per h?" "ur." "During most earthquakes," "The greatest damage occurs close to the epicentre." "This one is different." "Coastal areas suffer some significant damage." "But mexic?" "city, located 322 kilometers (200 miles) inland," "?" "ears the biggest brunt of the earthquake." "?" "izarrely, most of the city is barely damaged," "While small specific areas are alm?" "st completely destroyed." "Buildings between 6 and 1 5 st?" "ries high suffer the most." "Shorter and taller structures in the same bl?" "ck survive" "Virtually unscathed." "To solve the perplexing mysteries," "Lomnitz and his colleagues searched directly beneath their feet." "Cinna I?" "mnitz: mexic?" "city has a rather unusual location for a large city." "Seven hundred years ago," "What today is mexico city - was a lake." "?" "he aztecs built their capital city tenochitlan" "On an island in the middle of the lake." "It was a massive complex of canals and causeways " "With a structure as complex as any eur?" "pean city at the time." "When the spanish conquistadors captured" "?" "nd totally destroyed tenochitlan," "They filled in the lake and constructed their own city" "Directly on top of it." "Centuries later, this turned ?" "ut to be a ?" "ery bad idea." "Lomnitz: the sedimentary layer on which" "The downtown area is built on is a layer of ?" "ery soft clay" "It's practically jelly - it's almost water." "This ancient lake bed holds the key to" "The earthquake's strangely selective damage patterns." "Lomnitz: o?" "er the first three days after the earthquake" "We realised that severe structural damaged" "?" "ad ?" "nly ?" "ccurred in the former lake area." "The layer of soft lakebed was n?" "t just unstable " "It acted like a seismic amplifier " "Trapping seismic waves and actually boosting their strength." "just like jelly will keep wobbling" "Long after you shake it," "The layer of mud under mexico city" "Continued to shake for four minutes after the earthquake." "Lomnitz:" "this is the major cause of the disaster." "?" "ut that didn't solve the mystery of" "Why buildings between 6 and 1 5 stories" "Suffered the most damage." "The answer came in the f?" "rm of an?" "ther destructi?" "e combinati?" "n" "Of seismic waves and I?" "ose sediments " "?" "phenomena known as resonance." "Lomnitz: every object has a certain frequency" "That makes it resonate." "If a singer hits the right n?" "te," "They can shatter a glass just by subjecting it" "To its unique resonant frequency." "E?" "en a large object like a high-rise building can resonate." "Depending on its size and structure," "There is one energy frequency that will make it ?" "ibrate." "?" "y incredibly bad luck, the seismic waves" "Trapped and amplified by the layer of mud" "Under mexic?" "city were exactly the right frequency" "To make 6-1 5 st?" "rey buildings res?" "nate." "The buildings began to ?" "ibrate, shaking themsel?" "es t?" "pieces." "Others smashed into their neighbours like battering rams." "These freak circumstances doomed mexico city." "Many imp?" "rtant facilities such as hospitals" "?" "nd schools were in the fatal size range singled out" "?" "y the earthquake's fury." "The mexic?" "city quake was a tragic example" "Of the dangers of building on soft or reclaimed land." "The unstable soils amplified the quake's effects" "?" "nd unleashed complex and deadly patterns of resonance." "Today, buildings cann?" "t be constructed" "On the unstable lake bed." "?" "uilding codes and civil emergency plans" "?" "re enf?" "rced to help prevent future disaster." "The pe?" "ple of mexico city know" "They're at risk from earthquakes." "?" "ut milli?" "ns of ?" "thers li?" "e in striking distance of rare," "Mysteri?" "us quakes - and don't e?" "en know it." "?" "nd we're mo?" "ing closer to an even bigger quake " "?" "p?" "tential scenario that will c?" "mbine liquefacti?" "n," "Fire and other deadly side effects" "In a brutal mega disaster." "San francisco and mexico city b?" "th fell victim" "To earthquakes spawned by the ?" "olatile boundaries" "?" "etween tectonic plates." "?" "aIf the world's large cities are within" "Striking distance of maj?" "r faults like this." "But the other half are not necessarily out of danger." "?" "here is a t?" "tally different type of earthquake." "These rare rogue events strike," "Seemingly from nowhere," "Ra?" "aging areas thought to be immune to earthquakes." "Bhuj" "Date: january 26, 2001" "Magnitude: 7.7" "Type: intraplate" "?" "ey fact?" "rs: unexpected, high death toll" "january 26 is india's independence day." "?" "ut in 2001 , the celebrati?" "ns are forg?" "tten" "When a massive earthquake strikes" "The western pro?" "ince of gujarat." "The seven-point-seven quake destr?" "ys" "The historic city of bhuj along with many other nearby towns and cities." "20,000 people are killed and a million homes lost or damaged." "200 villages are wiped from the map." "paul bodin is a memphis tennessee based seismologist" "Who tra?" "elled to india to study the quake." "paul bodin: what we saw was an immense amount of devastation." "The human t?" "ll was incredible," "It was a horrible place to actually be doing the work that we had to do." "For scientists like bodin," "The most stunning aspect of the quake is not" "The scale of the damage " "?" "ut the fact that it occurred at all." "?" "ccording to the theory of plate tectonics," "This earthquake should not ha?" "e happened." "Central asia is no stranger to deadly quakes." "O?" "er a bilIi?" "n pe?" "ple live close to a massive tectonic collision," "?" "s the indian plate ploughs head-on into the rest of asia." "The himilayas, the largest continental mountain range on earth," "?" "re the crumpled wreckage of this collision." "This ?" "olatile plate boundary has spawned" "Numerous deadly earthquakes." "The 2005 kashmir quake killed" "?" "Imost 80,000 people in pakistan and northern india." "It was magnitude 7.6 - not huge but p?" "werful en?" "ugh" "To flatten hundreds of thousands of buildings." "?" "ut bhuj is 200 kilometres (1 24 miles) away from" "The dangerous himilayan plate boundary." "Large earthquakes sh?" "uldn't happen here." "paul bodin: but there's these rogue 5%" "That happen away from plate boundaries." "?" "nd we don't have a ?" "ery good understanding of why," "Of what dri?" "es these kind of earthquakes." "These mysterious rogue disasters are called intraplate quakes." "The 2001 bhuj earthquake was an important opportunity" "To study ?" "ne of these rare events." "?" "ut bodin and his team had a more urgent reason" "To tra?" "el from memphis t?" "india..." "The largest intraplate earthquakes in history happened" "Right in their own backyard." "New madrid" "Date: 1 81 1 - feb. 1 812" "Magnitude: 7.8-8.1" "Type: intraplate" "?" "ey fact?" "rs: multiple quakes, rare fault system" "In the winter of late 1 81 1 and early 1 81 2," "?" "he midwest of the united states was torn apart" "?" "y a swarm of massi?" "e earthquakes" "They were probably bigger than any quake to hit california," "?" "nd are named after an ?" "rdinary town" "With an extraordinary secret " "New madrid." "The magnitude of each can only be estimated" "Since seismic rec?" "rding instruments didn't exist." "?" "ut there is no doubt they were huge." "The first, estimated at magnitude 8," "?" "its ?" "n the 1 6th of december 1 81 1 ." "?" "ouses and buildings are torn apart." "Entire forests are wiped out." "Enormous cracks split and tear the earth." "The placid mississippi bec?" "mes a raging torrent" "Of rapids and waterfalls." "?" "ut this was only the beginning." "?" "month later," "?" "nother giant quake, estimated at magnitude 8," "Tears the frontier town of new madrid, missouri to pieces." "Two weeks after that a third magnitude 8 quake strikes." "O?" "er the next two months," "?" "Imost two thousands smaller trem?" "rs strike" "The effects are felt through?" "ut" "The entire eastern half of the united states." "paul bodin: in new madrid in the middle of the plate t?" "?" "a?" "e a large earthquake" " a huge earthquake - is ast?" "unding" "?" "nd then to follow it up with two other e?" "ents that" "Were as large or larger just incredible." "This incredible series of earthquakes seems to" "?" "a?" "e c?" "me from nowhere." "This is the flat stable centre of the n?" "rth american plate." "It's supposed to be safe from large earthquakes." "Reelfoot lake, 24 kil?" "meters (1 5 miles) from new madrid," "Is fam?" "us for its fishing." "?" "ut seismologist roy ?" "an arsdale hasn't come" "For the large mouth bass." "For him, reelfo?" "t holds the key to uni?" "cking" "The mystery of the new madrid quakes." "200 years ago, this lake didn't exist..." "Roy ?" "an arsdale:" "this serene swamp and lake area" "Was rocked se?" "erely during the winter of 1 81 1 , 1 812," "In a series of three giant earthquakes." "It was the third one in march that is responsible" "For the f?" "rmation of this lake." "Reelfoot lake's peaceful appearance is deceptive." "?" "eneath its calm waters scientists have made" "?" "n earth shattering discovery." "Roy: there's micro-seismic activity," "Meaning little earthquakes are occurring all the time out here," "So there are seismometers planted in the landscape ar?" "und us," "Measuring, recording these earthquakes" "Deep under reeIf?" "ot lake and new madrid" "Is a mysteri?" "us fault system that" "Spawned the huge earthquakes of 1 81 1 , 1 812." "It continues to generate small earthquakes today." "?" "ut this disc?" "ery raises e?" "en m?" "re questions." "If the new madrid fault is not a plate b?" "undary " "?" "hen what is it?" "The answer to that lies far away in ethiopia." "?" "his is part of asia and africa's great rift ?" "alley " "A fault system that stretches 4800 kilometers (3000 miles)" "From northern syria to m?" "zambique." "The earth here is splitting apart and bleeding molten rock." "A tectonic plate is being torn in half and pushed apart " "A process called rifting." "500 million years ago, this alm?" "st happened" "In the peaceful plains of the midwest..." "A surge of magma spewed up" "From the m?" "lten interi?" "r of the earth," "Eating thr?" "ugh the crust beneath the ancient midwest." "?" "ut before the plate was completely split," "?" "he magma retreated," "Leaving behind ?" "ast cracks in the earths crust." "?" "s pressure builds up on this fault system," "It's released as massi?" "e earthquakes." "?" "similar failed rift has been f?" "und" "Near the city of bhuj in india." "The buried rifts under bhuj and new madrid solved part of the mystery." "?" "ut there are still many things scientists don't understand" "?" "bout intrapIate earthquakes." "?" "hey have n?" "idea what triggers these r?" "gue disasters" "Or where they will strike next." "Roy: we really don't ha?" "e a good working model" "For what drives these intraplate earthquakes." "This is still quite the mystery in seismology, ge?" "logy," "That a number of us are w?" "rking ?" "n and" "We just don't have an answer to that right n?" "w." "In 1 81 1 and 1 81 2," "The new madrid earthquakes struck sparsely populated areas." "Today, millions of people living in cities like st louis and memphis" "?" "re within striking distance of the new madrid fault system." "If it wakes again," "The human and ec?" "nomic toll will be de?" "astating." "paul bodin: it would be foolish to think" "That it couldn't happen again that's its ?" "ver." "There's no scientific evidence that" "Whate?" "er is giving rise t?" "these earthquakes has gone away." "The new madrid quakes were" "The largest intraplate earthquakes in history." "?" "ut they pale in comparis?" "n to a massive tectonic rupture that" "Ripped thr?" "ugh chile, pr?" "ducing the largest earthquake on record." "?" "nd e?" "en that catastrophie is not the worst case scenario." "Experts belie?" "e a giant earthquake lies in wait," "One whose shock wa?" "es will ravage a nation," "?" "nd shake the entire planet." "There is ?" "ne earthquake that t?" "wers o?" "er all others " "One so massi?" "e it changed the shape of a nation" "?" "nd killed pe?" "ple half a w?" "Ird away." "This is a staggering e?" "ent that rates as the largest on record." "Chile" "Date: may 22 1 960" "Magnitude: 9.5" "Type: subduction" "?" "ey fact?" "rs: subsidence, tsunami" "In the small chilean town of mao-jin," "Life is quiet and simple." "Its fifteen hundred residents depend on the sea" "?" "nd the soil to survive." "?" "ut in 1 960, both elements conspired to decimate this peaceful place." "juana toledo was eight months pregnant" "When her w?" "rld was torn to pieces." "juana: i was at my sisters house and felt a m?" "vement." "Immediately i realised it was an earthquake" "Nelly delgaddo was als?" "caught by the earthquake's violence." "Nelly: we could not stand up." "We had to sit down and hold onto a fence." "?" "ut the fence started to move like this." "Then the earth started to open." "But the shaking in mao-jin is just the beginning." "?" "massi?" "e catastr?" "phe is spreading across chile," "Killing th?" "usands and shaking the entire nation to its core." "1 61 kilometers (1 00 miles) off the chilean coast," "The small, dense nazca plate slams into the much larger" "?" "nd lighter south american plate," "Creating a subduction zone." "This is far more dangerous than the one that offected mexico in 1 985 because here," "It runs the entire length of the c?" "ntinent." "On may 22nd, 1 960, the nazca subduction zone" "Spawns the largest earthquake ever" "?" "easured by scientists - a massive magnitude 9.5." "The amount of energy unleashed is equal to 32 billion tons (29 billion tonnes) of tnt," "Or m?" "re than 2 million hiroshima b?" "mbs." "The intense seismic wa?" "es tear apart cities caught in their path." "?" "uildings t?" "ppIe, the ground turns to liquid," "Landslides sweep down mountain slopes," "?" "nd cliff fronts c?" "llapse into the ocean." "The city of ?" "aldi?" "ia," "Close t?" "the epicentre of the quake is besieged..." "?" "Imost half the city is reduced t?" "rubble." "?" "ut this is just the beginning ..." "The fault rupture sets in motion a chain of events" "That ruin lives for generations" "?" "nd permanently scars the landscape." "Today valdi?" "ia is once again a thriving city " "?" "strategically imp?" "rtant point at the meeting of three ri?" "ers." "?" "ut take a cl?" "ser lo?" "k," "?" "nd there are secrets beneath the water..." "Mysteri?" "us streets that plunge into nowhere," "Drowned foundati?" "ns and ghostlike ruins al?" "ng the river's banks." "?" "he 1 960 earthquake did far more than shake things up " "It f?" "rever changed the shape of the land itself." "This ruined landscape is the victim of a side-effect of" "The massive chilean earthquake called subsidence." "Valdivia's fate was sealed hundreds of years before the quake." "For centuries pressure built up along the b?" "undary of" "The tw?" "great tectonic plates off chile's coast." "The s?" "uth american plate began to" "SI?" "wly bulge upwards under the strain." "When the fault ruptured in 1 960," "The strain was released on the south american plate." "It snapped back to its natural shape," "Lowering a vast swath of land two and half meters (eight feet)." "For the people of vaIdi?" "ia," "?" "his is a disaster that will last for generations." "Marc?" ": most of this area before the 1 960 earthquake used to be pastures," "?" "igh quality pastures." "The ground dropped two metres," "?" "nd n?" "w the tides every day cover this land." "There was huge damage on the economy of these people here" "?" "ecause they lost the best soil of the area." "O?" "er 200,000 square kilometres (77 thousand square miles)" "Of chile's c?" "ast subsided after the earthquake." "?" "ut incredibly, e?" "en this was not" "The most deadly part of the day..." "juana: they said we need to be prepared because the sea is coming in." "The tsunami is coming and we ha?" "e to climb up the hill just fifteen minutes after the massi?" "e quake," "?" "series of giant earthquake-generated tsunami wa?" "es" "Slam into the c?" "ast." "Some are 1 8 meters (60 feet) high." "From her vantage p?" "int on the hill abo?" "e mao-jin, juana watches as half the town is washed away." "juana: the wa?" "es were coming in trying to imprison us." "We heard an?" "ther wave coming" "Starting to mo?" "e the houses that were on the shore." "Making them hit ?" "ne another." "It was a terrific noise, a noise that scared us." "?" "ut nelly delgaddo had no time to get t?" "safety " "She was caught by the full fury of the wa?" "es." "Nelly: as the wave was advancing trees" "?" "nd other things were disappearing in its path." "I climb up in s?" "me trees." "?" "ut when the second wave came" "The trees were not strong en?" "ugh to us." "So i jumped onto a l?" "g and tried t?" "hold on" "?" "nd keep my face out of the water." "?" "nd then a boy climbed on the log t?" "o" "122 people from mao-jin drowned that night." "?" "ut somehow, nelly survived." "The giant waves wrecked ha?" "c far beyond chile " "They radiated out from the fault rupture," "Striking ?" "ther unsuspecting pacific locations." "1 5 hours after the earthquake struck," "The tsunami reached hawaii." "The port city of hilo was devastated " "?" "nd 61 li?" "es lost." "Seven hours later," "The tsunami hit japan killing 1 22 people." "The philippines and the west coast of" "The united states als?" "felt the wa?" "es of destruction that day." "When it was all ?" "ver, the great chilean earthquake" "?" "illed 2000 and left 2 milli?" "n homeless." "It remains the largest earthquake ?" "n record." "?" "ut records were made to be broken..." "Scientists believe an?" "ther giant earthquake" "Lies in chile's future - one that could be much, much worse." "The evidence p?" "inting t?" "wards a mega disaster" "Lies ?" "n a remote section of c?" "astline in southern chile." "This was once a big f?" "rest," "Until the 1 960 earthquake and tsunami de?" "astated" "The area and left ?" "nly twisted stumps." "?" "o the trained eyes of ge?" "logist marco cisternas," "This deserted beach holds vital clues to chile's seismic future." "Marco cisternas:" "the 1 960 e?" "ent wasn't a unique e?" "ent." "?" "lthough it was a giant, but it was not unique." "In this you can see there is a soil, a buried soil here." "This is 1 960s soil covered by a tsunami sand layer here." "?" "nd below that you can find another soil" "Corresponding to the 1 575 earthquake." "?" "I?" "ng this coast, there is e?" "idence of an?" "ther dozen earthquakes" "That ravaged the area in the last 2000 years." "Marco cisternas:" "so it is certain that in the future," "?" "nother giant earthquake is going to strike central chile." "When it strikes, it will be a mega disaster " "?" "n event that will cripple a country" "?" "nd send shockwa?" "es around the entire planet." "In 1 960 the biggest earthquake ever recorded rocked chile." "Thousands died and" "The landscape of the country changed fore?" "er." "?" "ut scientists belie?" "e a far more destructive quake" "Could be on chile's horizon..." "Don windeler is an expert in modelling disasters of the future." "Using data from the giant 1 960 quake," "?" "nd input fr?" "m some of the world's leading seismologists," "Windler and his colleagues ha?" "e created" "Sophisticated m?" "deIs of potential earthquakes in chile " "Including the mega w?" "rst-case scenario." "Don windeler:" "there's n?" "stopping the nazca plate" "From going underneath s?" "uth america." "We will continue to see large events over time in chile" "It's just a fact of life." "The massive 1 960 earthquake struck in the centre" "Of the c?" "untry where the population was relati?" "ely light." "?" "ut if the nazca fault ruptured further north," "Near t?" "chile's largest cities," "?" "major catastr?" "phie would result." "Don windeler: we're going to expect to see a lot more economic loss," "?" "lot m?" "re casualties resulting from this event" "Mega-quake" "Date: to be determined" "Size: 9.5" "Type: subduction" "?" "ey fact?" "rs: subsidence, liquefaction, tsunami" "Valparaiso is one of chile's maj?" "r p?" "rts" "?" "nd h?" "me to its navy and houses of parliament." "?" "he city sits in an amphitheater facing the ocean." "Most of its 270,000 inhabitants live on the steep hills abo?" "e and" "?" "re carried to their h?" "mes by unique machines called funiculahs." "just up the coast fr?" "m valparaiso" "Is the tourist resort of ?" "ina del mar," "Fam?" "us for its beaches and luxury hotels." "Valparaiso and vina del mar are both part of" "Chile's m?" "st valuable stretch of land." "If hit by a major earthquake, the nation would be ra?" "aged." "Windeller: just that one area from valparais?" "?" "cr?" "ss the c?" "untry thr?" "ugh santiag?" "metropolitan area contains" "O?" "er 50 percent of the property ?" "alue for the country of chile" "?" "nd any kind of event that has significant serious damage" "To that area is going to have repercussions to" "The economy of the country." "Windeler's nigthmarish scenario begins 27 kilometers (1 7 miles)" "Under the earth and 80 kilometers (50 miles) off the c?" "ast" "In the collisi?" "n z?" "ne between the nazca" "?" "nd south american plates." "?" "stress point snaps, starting a chain reaction." "More than 1400 kilometers (870 miles) of the subduction zone" "Rip open up like a zipper." "Massi?" "e seismic sh?" "ckwaves spread fr?" "m the rupturing rock." "The primary wa?" "es speed ?" "ut" "?" "t 29-thousand kilometers (1 8 thousand miles) per hour." "The arrival of the p-wa?" "es in ?" "alpairiso" "Feels like a long s?" "nic boom." "Windows and buildings shudder." "Some of the p-waves sho?" "t up into the atmosphere," "Emitting a frightening roar." "The secondary waves follow," "Carrying most of the earthquake's energy." "Some surface wa?" "es shake the ground from side to side," "Twisting railway lines and shattering concrete structures." "?" "uildings are shaken from their foundations." "Unstable areas of the cliffs surr?" "unding ?" "alparais?" "collapse," "Taking many buildings with them." "Below in the port, sediments amplify the seismic energy, pr?" "longing the shaking and the destruction." "Liquefaction ruptures gas mains," "Water pipes and vital communication links." "In addition to the deadly seismic waves," "The earthquake rupture releases pressure on" "The s?" "uth american plate." "It pushes forward and flattens." "?" "reas of the coast sink two meters (se?" "en feet)." "Entire structures collapse and flooding is rampant." "Fires caused by br?" "ken gas mains rage out of control." "?" "s the city lies paralysed and in ruins," "The biggest killer of all is ab?" "ut to strike." "?" "s the s?" "uth american plate is released and flicks upwards," "It pushes up an enormous wave of water 967 kilometers (600 miles) long." "Gravity quickly pushes it back," "Creating a massi?" "e wa?" "e - a tsunami." "One side of the wave rushes towards the coast of chile." "It takes just ten minutes to reach vina del mar." "It hits the already besieged city" "With a 12 meter (39 foot) wall of ocean that" "Smashes across the city." "Thousands more lose their lives." "The city is de?" "astated." "?" "ut the giant earthquake's deadly reach extends" "Far bey?" "nd chile." "The same tsunami that pulverised vina del mar" "Speeds across the pacific for thousands of kilometers (miles)." "?" "ours after the quake, huge waves strike new zealand," "?" "awaii, and japan." "The west coast of the usa and the philippines" "Will also be hard hit." "Chile's mega - earthquake is now a global disaster." "Don windeler: taking the 1 960 earthquake," "This massi?" "e magnitude 9.5," "?" "nd m?" "ving it closer to ?" "alparaiso and santiago" "Is something that's not likely to happen in any near future," "?" "ut at the same time gi?" "en what we know ab?" "ut" "Chile's tectonics and past history," "It's very difficult to exclude that from saying that it can occur" "Chile's mega disaster will probably not happen" "Within our lifetimes." "?" "ut scientiest believe a major city will be struck" "?" "y a de?" "astating earthquake." "Don windeler: we're setting ourselves up for larger catastrophes," "Should an event ?" "ccur near one of those cities." "Experts agree that while it's impossible" "To pre?" "ent an earthquake," "It is possible to prepare for ?" "ne." "Cinna lomnitz:" "there are many things we don't know" "?" "bout earthquakes, but we do know ?" "ne thing" "The way to avoid disaster is to be prepared f?" "r them." "When there is no surprise, there is no disaster." "paul bodin: the danger is that if we're not prepared" "If we don't prepare ?" "ur cities for the hazard" "That exists there will be hell to pay." "?" "alf the world's populati?" "n now lives in cities - placing hundreds of millions" "Within striking distance of an earthquake." "For all of them, the cl?" "ck continues to tick" "On these giant underground time bombs."