The shaking has slowed for now, the sense of panic eased, the search for the missing ebbed. But six months of tremors, including one major earthquake, have left many in this remote corner of Patagonia unhinged.
The picture-postcard scenery of heavily forested hillsides and placid inlets has become pregnant with menace.
"The scariest prospect is a giant tsunami inundating the town while the mountains come tumbling down on top of us," said Paula Salazar Campos, among the bolstered ranks of psychologists attempting to heal traumatized psyches here. "Some people just can't get over that thought."
Boris Pualuan, whose family has run a general store across from the central plaza since 1928, is among the rattled. "Some people are sleeping all day," he said. "And some people don't sleep at all."
Sister Augusta Pedrielli is an Italian-born Catholic nun who has lived here for more than four decades. "People are afraid Puerto Aisen is going to disappear," she said.
The daily tremors began in late January and now number more than 7,000. The shakes culminated in a 6.2 magnitude earthquake on April 21 beneath nearby Aisen Fjord that sent chunks of hillside plunging into the inland waterway, generating waves that swept away fishermen, salmon farm workers and others. Three people died and seven others are missing, presumed dead.
The killer waves dissipated short of town, but the ground here trembled mightily, cracks opened in the earth, debris tumbled from mountains, and the town's signature suspension bridge swayed like a Slinky. Puerto Aisen's geologic vulnerability was suddenly exposed, alarming residents accustomed to tranquillity.
As much as 15% of the population of 30,000 here and in the nearby port of Puerto Chacabuco has left, officials said.
"This emergency is not over: We don't even know if the worst is over," said Carlos Aranda, chief of seismology at the University of Chile.
Many of the people who live along the seismic-volcanic "ring of fire" that encircles the Pacific Ocean learn to live with the near-certainty that a significant earthquake will strike in their lifetime. Few expect six months of nerve-jangling jolts.
The shaking continues, scientists said, though recently it has not been as perceptible to residents.
The mystery about what exactly is going on here has drawn experts from across the globe to this nook of the Chilean coast, about 800 miles south of Santiago, the capital. Scientists debate whether magma below ground may be at play in a zone where active volcanoes are found to the north and south.
Three tectonic plates clash near the Chilean coast, making the region one of the most tectonically active in the world. The largest measured earthquake, a 9.5 magnitude temblor, struck in 1960 near Valdivia, about 400 miles north of here, according to the U.S. Geological Survey.
The April 21 earthquake occurred on a long-identified fault system, Liquiñe Ofqui, which stretches for about 750 miles along the Chilean Andes.
But some parts of the moon have been better mapped than this stretch of the Pacific coast. And the quake destroyed much of the measuring equipment placed in the fjord.
"We're starting from way far behind," lamented Andres Pavez, a Chilean geophysicist who is part of the multinational team hoping to save lives by determining what's next.
The prevailing uncertainty has fanned fears and imaginations along this rainy, fog-shrouded coastal strip.
People have gotten used to sleeping in their clothes, drawing the curtains and keeping their kids home from school.
They report broken marriages, increased alcoholism and depression, and a sense of impending doom.
"We noticed the children are more aggressive, fighting all the time," said Maria Teresa Aedo, principal at Holy Family elementary school, where attendance has plunged. "They're not getting enough sleep. The tremors have caused a lot of stress at home. Some mothers have just taken their children away and left their husbands behind."
The fate of another sleepy South American town, Armero, Colombia, haunts Puerto Aisen's mayor, Oscar Catalan. Armero was buried in 1985 after the Nevado del Ruiz volcano erupted, sending walls of mud and debris down its flanks. More than 23,000 people died. Authorities could do little but declare the site hallowed ground.
"We don't want to be the next Armero," Catalan, a burly chain-smoker, repeated several times during an interview in his office, his face wrinkled with worry. "We're very isolated here. Landslides could take out the main road and people would be trapped."
Catalan, who narrowly escaped being swept up in the April 21 quake, has become a folk hero for his blunt condemnation of state and federal officials who minimized the peril.
A government flier distributed before the April quake assured residents of two comforting scenarios: The shuddering would "gradually" wane, or an underwater volcano would erupt "without consequence for people."
From the mayor's standpoint, the fjord should have been declared off limits before April 21. Scientists had identified the waterway as the epicenter of the earlier tremors.
"The earthquake was inevitable," he said, "but the loss of life was not."
People traveling in the fjord before the quake had reported strange phenomena: erratic tides, lightning emanating from the nearby Maca volcano, and sulfurous gases belching from the waters.
As the tremors mounted, apocryphal tales swirled of crabs and other shellfish emerging cooked from the cool Pacific.
"We knew something wasn't right," said Ruben Contreras, part of a fishing clan that lived in the settlement of Playa Blanca, along the coast of the fjord and less than 2 miles from the epicenter.
The quake struck as almost 200 workers were on duty at salmon farming pens in the fjord. Four of the missing are salmon industry laborers.
"No one should have been in the water that day," said a disconsolate Irma Ruiz, grandmother of Miguel Angel Silva, 22, one of two salmon farm watchmen buried in the rubble April 21 and presumed dead.
"Miguel Angel told us it was shaking so much they could hardly sit down to eat a meal in peace. But he kept working to bring something home for his family."
A portrait of the lost salmonero, framed by two sets of rosary beads, hangs on the wall of the family's home.
His uncle, a scuba diver for the salmon industry, also was on duty that day. He and co-workers scrambled into a boat and rode out the swells. The middle of the fjord was safer than the shallows and coast, which were inundated by landslides and battered by waves of almost 40 feet.
Mayor Catalan headed a relief committee that was delivering a radio transmitter to Evaristo Contreras, the family patriarch at Playa Blanca. The aid contingent headed out to Playa Blanca in a rented boat. It was the morning of April 21. A beaming Contreras, donning his trademark gaucho beret, came down to the dock.
"He told us the place had just gotten two big jolts," recalled Hugo Guerrero, a journalist who accompanied the aid mission.
The quake struck about 10 minutes later. Witnesses reported loud blasts, possibly land ripping from the mountains, and saw hillsides tumbling across a 4-mile strip of shoreline. A column of water rose like a giant geyser. Swells approached the coast.
"I realized death was near," said Catalan, who, along with the others, scrambled to higher ground.
Two of the 19 people in the aid mission, Francisco Figueroa and his 14-year-old daughter, Melissa, were caught in the surf and haven't been seen again.
The mayor said he last glimpsed Evaristo Contreras sprinting toward his cabin. His wife, Elsa Poblete Carrasco, was hastening to embrace her husband. A giant wave was closing in.
"Their fates were sealed at that point," Catalan said, "but seeing that act of love was overpowering."
The couple's bodies were recovered about half a mile away.
Julio Linay, Contreras' son-in-law, said he fought the waves and currents for more than two hours before reaching the coast, exhausted.
However, Linay's wife and 2-year-old son were lost; only the boy's body has been recovered.
"I don't know why I'm even alive," the shellshocked Linay said recently. "I ask myself: Is life worth living now?"
After the quake, angry residents greeted President Michelle Bachelet with Bronx cheers and black flags; the enraged mayor even ended up in jail for a spell on disorderly conduct charges.
Since the tragedy, the government's attitude has changed dramatically: No official is minimizing the danger now. Indeed, talk of Armageddon is everywhere here. More than a dozen emergency centers stocked with flashlights, blankets, boots and other supplies have been set up.
Bachelet has returned to Patagonia and unveiled with a massive aid package, including a new hospital, gymnasium and better roads and access. The government has pledged to spare no expense in early-warning systems and evacuation plans.
But Puerto Aisen's economy, dependent on salmon farming and tourism, may not recover quickly. The annual cruise ship stopovers seem likely to be put off. The salmon industry is making plans to pull out of the unstable fjord. No one knows how many of the 14 million young fish being fattened in the waterway died or escaped.
The big challenge for residents is learning to live with a perpetual threat that has altered this drowsy town forever.
"This is now an active seismic zone: People have to get used to it," said Salazar Campos, the psychologist at the hospital. "Once the residents of Puerto Aisen realize that, they will have a more realistic vision of how their lives will proceed from now on."
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