The death toll in Indonesia's twin quake-tsunami disaster climbed to 1,424 on Thursday with time running out to rescue survivors six days after the disaster struck.

Residents on Sulawesi Island's west coast scavenged for food in farms and orchards as the government struggled to overcome shortages of water, food, shelter and fuel in a disaster zone with no power and degraded communications.

Most of the confirmed dead were in Palu, while losses in remote areas are yet unknown.

Communication links are down and bridges and roads have been destroyed or blocked.

In 2004, an earthquake off Sumatra island triggered a tsunami across the Indian Ocean that killed 226,000 people in 13 countries, including more than 120,000 in Indonesia.</s>An injured man is brought to the hospital as one woman cries after learning about her daughter's death in a massive earthquake and tsunami in Palu, Central Sulawesi, Indonesia Thursday, Oct. 4, 2018. Nearly a week after a magnitude 7.5 quake spawned a deadly tsunami on Indonesia’s island of Sulawesi, countless people have yet to find their loved ones _ both survivors and the dead. As of Thursday, the official death toll was 1,424, with 113 people missing. Many families, though, never registered their losses with police, and others have failed to identify them before they were buried anonymously in mass graves.(AP Photo/Aaron Favila) (AP)</s>Nearly a week after an earthquake struck Sulawesi, spawning a massive tsunami that overwhelmed the Indonesian island's central coast, aid groups are finally getting a foothold in the badly battered region — though challenges remain immense for relief and recovery efforts.

"Some people are now receiving basic food items like rice, noodles and canned food, but this remains a small minority. The food situation in Palu remains dire, and with the market closed we're even struggling to feed ourselves," said Genadi Aryawan, a Mercy Corps team member stationed in the city.

The tsunami that swept Sulawesi hammered Palu the hardest of the cities in its path. Of the more than 1,500 people who were killed in the catastrophe, the vast majority hailed from the city of nearly 300,000. And days later, fuel, sanitation and reliable information are still in short supply.

"Rumors are flying around the camps that another earthquake is imminent, one that will 'sink' Sulawesi," Aryawan added. "The situation is incredibly tense, and people are becoming increasingly panicked as misinformation compounds an already desperate situation."

Also compounding Indonesia's woes was the eruption of a volcano on the Sulawesi's northern peninsula. Mount Soputan sent a plume of ash towering nearly 20,000 feet into the sky Wednesday, hundreds of miles from where the quake and tsunami struck. Since then, it has continued to spew lava.

No evacuations have been ordered because of the eruption so far, but people have been warned to stay as far as 4 miles away, according to Sutopo Purwo Nugroho, spokesman for BNPB, Indonesia's disaster response agency.

Meanwhile in Palu, some 600 miles south of the volcano, it is not lava but water that concerns Oxfam the most. Hobbled by broken roads and damaged airports, the international aid organization says it is sprinting to scale up its efforts to get clean water to half a million people in need.

"The scale of the damage from the earthquake and tsunami is huge and there are fears many bodies are buried under collapsed houses and buildings," Oxfam's humanitarian manager in Indonesia, Ancilla Bere, said in a statement Thursday. "In many areas of Palu and surrounding towns, there is no running water and few working toilets — and sanitation is a serious concern."

NPR's Julie McCarthy described the brutal scene she confronted upon arriving in Palu.

"Lining the roads are small children. And they're chasing you, and they're asking for food. And they're holding up signs that say, 'We also need food. We, too, need food,' " McCarthy said.

"As you move into Palu, you see along the bay just nothing but houses that have been snapped like twigs," she added. "You see cement homes that are leaning into the bay. And every part of human existence is strewn among the debris."

But it is not just Palu that is suffering in the aftermath. McCarthy notes that other areas hit hard by the disaster, such as Donggala, have so far gotten less attention from aid groups than their larger counterpart — though that's not for lack of trying.

"Red Cross responders are pushing their way through debris and damaged roads to reach new areas and try to help the survivors, and they are finding devastation and tragedy everywhere," Iris van Deinse of the International Federation of Red Cross and Red Crescent Societies said in a statement Wednesday.

Van Deinse said she had been with an IFRC team that sought to bring supplies to the small village of Petobo, near Palu — only to discover that, for all intents and purposes, the village no longer even existed.

"When we arrived in Petobo, we found that it had been wiped off the map by the power of the tsunami," she explained.

There are some signs of hope. Heavy machinery and military transport aircraft have arrived for rescue efforts in Palu, and The Associated Press reports that workers have begun to rebuild the city's power grid.

Still, with more than 2,500 people injured and tens of thousands of buildings destroyed, authorities expect the death toll to climb further. And time is dwindling quickly for rescuers to find survivors.

"Any delay in a disaster costs lives," said Tim Costello of World Vision, "and there have been delays."</s>A volcano erupted Wednesday on the same island in Indonesia where an earthquake and tsunami last week killed at least 1,400 people.

The eruption of Mount Soputan on Sulawesi island in central Indonesia prompted authorities to warn of possible lava flows and ash clouds that could impact air travel. Evacuations were ordered for those living within a few miles of the volcano.

The eruption spewed ash 19,700 feet into the sky.

Scientists have not yet determined whether the eruption was directly triggered by the earthquake in central Sulawesi on Friday. However, Indonesian news portal Tempo cited a government volcanologist who suspected it was.

Indonesia has many actives volcanoes. It is also located in the so-called Ring of Fire, one of the most active areas for earthquakes in the world.

President Donald Trump called Indonesian President Joko "Jokowi" Widodo on Tuesday to offer assistance with both the emergency phase and reconstruction from the earthquake and tsunami that struck Sulawesi.

More: Indonesia tsunami: As desperation mounts, relief groups mobilize; here's how you can help

More: No, the giant Katla volcano in Iceland isn't about to erupt

In addition to the growing death toll, hundreds of people were severely injured in Friday’s disasters. With many roads blocked and key communication lines and infrastructure destroyed, food, water, fuel and medicine are struggling to reach the hardest-hit areas outside Palu, the largest city heavily damaged. More than 60,000 people have been displaced, according to the National Disaster Mitigation Agency.</s>When an earthquake strikes, the sensors capture the movement of ocean waters, giving authorities precious time to alert residents to move to higher ground.

But the destructive tsunami that hit Indonesia on Friday highlights a critical flaw in the systems.

If a big quake strikes too close to shore, it won't be detected by those deep-sea sensors, and the wave can arrive before major evacuations occur. That's what happened on the Indonesian island of Sulawesi, when a magnitude 7.5 earthquake hit just north of a narrow bay, sending waves as tall as 20 feet straight into Palu, a town where at least 1,200 people were killed.

Scientists said California faces similar vulnerabilities. Low-lying stretches of the coast are susceptible to damage from a tsunami, and there has been a push in recent years to improve safety protocols.

In Southern California, an earthquake could trigger an underwater avalanche in the Santa Monica Bay, producing a tsunami that could inundate low-lying areas of Santa Monica and the South Bay towns of Manhattan Beach, Hermosa Beach and Redondo Beach, said Costas Synolakis, a University of Southern California civil and environmental engineering professor and tsunami expert.

"This is exactly the scenario we are afraid of in Southern California," Synolakis said, "where we are going to get an on-land earthquake ... and the biggest shaking triggers a submarine landslide. ... This is kind of a nightmare ... that's hard to prepare against."

With only minutes between the shaking and the tsunami, it's possible no official early warning may come. It was only about 10 minutes between the earthquake and the first wave that washed across Palu, said California Institute of tTechnology seismology professor Pablo Ampuero. When a quake hits farther out in the ocean, officials can have hours to evacuate residents before the waves hit land. But on Friday, they had only minutes.

And when a tsunami warning was issued by the Indonesian government, the public may not have received the alert, Ampuero said, because the quake knocked out electricity and communications systems.

It is a scenario that could be repeated in Southern California.

During the great 2011 Japan tsunami, some of the first detailed alerts underestimated the size of the tsunami to be lower than the protective sea walls on the coast. Then the communications were cut off, leaving the public with a false sense of security.

Though tsunamis get less attention than earthquakes in California, officials have warned the state needs to be better prepared—and to better understand the deadly risks. In 1964, 11 people died when waves slammed into Crescent City, inundating the downtown area. In 2011, hours of warning enabled an effective evacuation of Crescent City, although one man, taking photos of the tsunami at the mouth of the Klamath River, died after being swept to sea.

Tsunami science has improved since the 1980s, thanks to a new generation of detection equipment. Nations rallied to fill in gaps in the global network after the 2004 Sumatra tsunami exposed shortfalls, including the lack of a network in the Indian Ocean.

Some news reports after Friday's quake initially focused on the state of disrepair of Indonesia's network of nearly two dozen deep-sea sensors as a possible factor in the loss of life. The German-funded effort never produced a working system, Synolakis said.

Synolakis and others, however, said that even having a working deep-sea sensor network of the kind used by the United States and other nations—known as DART—may not have helped. Deep-sea sensors are more intended to detect tsunamis that are farther from its destination, not a matter of minutes away from the shoreline.

"The DARTs are really wonderful for judging a tsunami and figuring out how it's going to be on the far side of the ocean," said Gerard Fryer, former geophysicist at the Pacific Tsunami Warning Center in Hawaii. "But for warning of a local tsunami, they're just not enough. They might help if you're lucky if you've got one in just the right place. But they probably won't."

Giving warning of a nearby tsunami would probably require a new technological solution. One idea, Fryer said, is blanketing the seafloor of an area particularly at risk of tsunamis with underwater microphones, and then developing a computer program to send out the alerts. But, he said, "that's not something we can do off the shelf right now."

But there are things that could have been done to better prepare Palu for what happened. For one, Palu has had a history of dealing with damaging tsunamis. A magnitude 7.8 earthquake led to a tsunami that killed 200 people in 1968, Fryer said, and there were deaths from tsunamis generated by a magnitude 7.6 earthquake in 1938 and a magnitude 6.3 earthquake in 1927.

A key reason lies in Palu's geography. Sitting at the end of a narrow, finger-shaped bay is one of the worst locations to be in if a tsunami enters the inlet. Water rushing into a bay that gets progressively shallower can allow it to push on to land.

In fact, tsunami translates from Japanese literally as "harbor wave," as the towns known to be clobbered by tsunamis were at the long end of narrow harbors on the northeastern coast of Japan's Honshu island, Fryer said. The same dynamic led to damage in Port Alberni, at the end of the Alberni Inlet, on Vancouver Island in the great 1964 Alaska earthquake.

"These bays, they tend to funnel the energy. It's almost like a bull's-eye is where the city is," Synolakis said.

Experts say it makes sense for people along the coast to seek higher ground in a major quake.

"If you feel strong ground shaking and it lasts for 10 to 15 seconds or so, or maybe even less—don't take any chances. If you're in a coastal area or along the beach, move uphill and inland as quickly as possible," said Stuart Weinstein, deputy director of the Pacific Tsunami Warning Center in Hawaii. "You can self-evacuate. The worst case is you take a fast walk for nothing; on the other hand, it could save your life."

A general rule is to climb 50 feet to 100 feet above sea level. Sometimes, it may be better to evacuate vertically up a tall concrete or steel-frame building. A two-story wood-frame home is not high or sturdy enough, experts say.

Friday's tsunami was seen as unusual. The largest tsunamis in the world are generated from what's known as subduction zones, in which one tectonic plate slides underneath another. Earthquakes on subduction zones can generate vertical motion that propel tsunamis to land.

But this tsunami was generated after a quake began on land on a strike-slip fault—the same kind of fault as the San Andreas, where one block of land slides past the other horizontally. This produces horizontal movement not typically associated with large tsunamis, yet is still possible, as Friday's disaster showed.

There are other possible explanations for why the tsunami hit Palu so hard. One is that the bay started moving back and forth, like someone shaking a mug filled with coffee, causing the liquid to slosh onto land, Synolakis said.

Another possibility is that the fault movement caused just one side of the bay to move, pushing water toward the other side, Synolakis said.

One thing is clear: Technology cannot be the only answer to tsunami warnings, especially in Indonesia, with its 17,000 islands.

"The shaking is your natural warning," Ampuero said.

Eddie Bernard, a former director of the Pacific Tsunami Warning Center, expressed sympathy for his tsunami scientist colleagues in Indonesia.

"They did the best they could with the information they had available," Bernard said. "A tragedy like this, everybody feels sad. But in time, more information will become available and maybe from this we'll learn more about what to do next."

Explore further: Indonesia tsunami worsened by shape of Palu bay: scientists</s>(CNN) — Rivers of soil swept away entire neighborhoods in Indonesia following a powerful earthquake last week that also generated a tsunami in a disaster that has killed at least 1,407 people.

Experts say the destruction is due to soil liquefaction, a process occurring when soil becomes saturated with water causing it to erupt into tumultuous torrents, as it did on Friday, shifting and tumbling buildings.

Footage has emerged from the stricken city of Palu showing people running to find solid ground as structures were swept away and destroyed by waves of undulating earth. Images show a section of the city being erased by surging soil.

In Petobo town the ground under the length of an entire main road was torn up, with the tide of soil leaving broken stretches of tarmac-topped debris in wave-shaped mounds and troughs.

“Liquefaction occurs when loose sandy soils with shallow groundwater are subjected to sudden loading such as shaking from an earthquake,” said Jonathan Stewart, professor of Civil and Environmental Engineering Department at UCLA.

Many experts liken the process to waves lapping on a sandy beach. When the waves come in, the sand softens, but when the waves withdraw, the sand stiffens.

“During the earthquake, water pressure is generated in the soil, which causes a dramatic loss of strength,” said Stewart. “The strength loss can be so great that the soil behaves almost like a liquid.”

Soil running downhill, known as “flow failure,” is one of the most severe effects of liquefaction, and prone to occur in areas with a particular soil structure.

“The soils in the slide area are likely geologically young, loose, sandy materials with shallow groundwater,” said Stewart.

Was the earthquake triggered by a volcano?

Scientists say that the devastating sequence of natural disasters were the result of a highly unusual series of geological events, which may be related to the eruption on Wednesday of the Soputan volcano, also on Sulawesi island.

“Did the bulging magma chamber of the volcano trigger the earthquake? Or did the earthquake trigger the magma chamber to pass magma to the funnel of the volcano?” said Professor Costas Synolakis, director of the University of South California Tsunami Research Center.

According to Synokalis, volcanic eruptions are very often preceded by swarms of earthquakes, which are typically smaller than magnitude 5.

“It is all beginning to look like a Hollywood movie scenario,” added Synokalis. “A (7.5 magnitude) earthquake with a mechanism not usually associated with tsunamis triggers a big one, and volcanic activity at a distance from the earthquake far larger than usually expected for causation.”

The epicenter of Friday’s earthquake was on land and not at sea, meaning the probability of a tsunami was low. Many experts have theorized that the tsunami was therefore triggered not by the earthquake itself but by a submarine landslide caused by the earthquake.

Though such a chain of events are rare and therefore difficult to mitigate, scientists say that engineering techniques do exist to lessen the impact of soil liquefaction.

“As with most problems, the first step in mitigation is recognizing that a problem exists,” said Stewart. “We have engineering procedure for this. Had they been applied, there is a good chance the hazard would have been recognized.”

Several techniques are used to stop flow slides. The easiest is the construction of a strengthened zone in the soil near the lower end of the slope, said Stewart.

Approaches to this in geotechnical engineering include densification of the soil by the injection of materials, or the compaction of sediments and soils using weights or vibration that mimic earthquake processes, said Adam Switzer, principal investigator at the Earth Observatory of Singapore.

Another method, he added, is the use of “earthquake drains'” that aim to mitigate liquefaction by releasing pressure before it reaches critical levels.

Synolakis said that other ways to treat liquefaction is to avoid building multi-story structures and regulate to require deep foundations.

But in poorer countries these techniques might be too costly for government and individual budgets.

“Many of the mitigation techniques are likely to be well beyond the means of the average homeowner in southeast Asia,” Switzer told CNN.

In absolute terms careful choice of construction sites or relocation are the best defense against soil liquefaction, scientists said.

“The only way to completely mitigate the problem would be to… move developments off the liquefied soils,” said Stewart.

The process is thought to have played a key role in previous disasters, such as the Japan earthquake in 2011, where the extent of the liquefaction over hundreds of miles was daunting to experienced engineers.

A study found that liquefaction wrought more devastation than shaking in the Christchurch, New Zealand, earthquake in 2011.</s>When a devastating earthquake and tsunami struck central Sulawesi, Indonesia on Friday, survivors found even the ground beneath their feet offered no safety: it had turned to liquid.

Many who attempted to find shelter were trapped by waves of earth that churned like water, the result of an earthquake process known as liquefaction.

“The ground rose up like a spine and suddenly fell. Many people were trapped and buried under collapsed houses. I could do nothing to help,” one survivor told the Associated Press this week.

The official death toll from the twin disasters — a 7.5-magnitude earthquake that triggered a tsunami — stood at 1,234 on Tuesday. But officials expect the number to rise as rescue workers dig more bodies from under collapsed buildings.

Much of the damage was wreaked by liquefaction. In one neighborhood, an estimated 1,700 houses were consumed by the roiling earth, according to Indonesia’s national rescue agency.

Here’s what to know about the nightmarish phenomenon:

The U.S. Geological Survey explains liquefaction as a process that occurs when water-saturated soil, shaken by an earthquake, acts like a liquid. The ground temporarily loses its ability to bear structures like buildings or homes, often with deadly results.

Earthquake tremors can cause the water-logged soil to oscillate like waves, flow down inclined slopes, or be ejected upward in formations called “sand boils.”

Liquefaction also often causes the ground to settle unevenly, which can upset roads, bridges, pipelines and other infrastructure.

Where does it happen?

Areas near bays or marshland that were filled with dredged or reclaimed land are most vulnerable to liquefaction, according to the U.S.G.S. Land that is made of loose, granular sediment like sand is also highly susceptible.

Liquefaction has been observed during other major earthquakes, such as during the 1989 Loma Prieta earthquake in California, or the during the 1948 Fukui earthquake in Japan, when an estimated 67,000 homes were destroyed and 3,894 people were killed.

Why was it so damaging?

Conditions for liquefaction were ripe in Palu, the seaside town that bore the brunt of Indonesia’s recent disasters. Palu sits at the end of a bay, and is surrounded by a river delta.

Videos of the earthquake in action show buildings crumbling or even more unnervingly, pitching across the ground as if bucked by waves. Trees and telephone poles were uprooted and sent flying, or else consumed by the roiling soil.

“When the quake hit, the layers below the surface of the earth became muddy and loose,” Sutopo Purwo Nugroho, the spokesperson for Indonesia’s national rescue agency, told Reuters.

Among the victims were 34 children attending a Bible study camp, who were killed when their church collapsed from liquefaction, according to a Red Cross official.

Another 2,000 people are feared dead in Petobo, south of Palu, after a quake-triggered mudslide washed away homes, the Jakarta reported Monday. Local residents said the mud flowed “like waves,” according to the .</s>Nearly a week after an earthquake struck Sulawesi, spawning a massive tsunami that overwhelmed the Indonesian island's central coast, aid groups are finally getting a foothold in the badly battered region — though challenges remain immense for relief and recovery efforts.

"Some people are now receiving basic food items like rice, noodles and canned food, but this remains a small minority. The food situation in Palu remains dire, and with the market closed we're even struggling to feed ourselves," said Genadi Aryawan, a Mercy Corps team member stationed in the city.

The tsunami that swept Sulawesi hammered Palu the hardest of the cities in its path. Of the more than 1,500 people who were killed in the catastrophe, the vast majority hailed from the city of nearly 300,000. And days later, fuel, sanitation and reliable information are still in short supply.

"Rumors are flying around the camps that another earthquake is imminent, one that will 'sink' Sulawesi," Aryawan added. "The situation is incredibly tense, and people are becoming increasingly panicked as misinformation compounds an already desperate situation."

Also compounding Indonesia's woes was the eruption of a volcano on the Sulawesi's northern peninsula. Mount Soputan sent a plume of ash towering nearly 20,000 feet into the sky Wednesday, hundreds of miles from where the quake and tsunami struck. Since then, it has continued to spew lava.

No evacuations have been ordered because of the eruption so far, but people have been warned to stay as far as 4 miles away, according to Sutopo Purwo Nugroho, spokesman for BNPB, Indonesia's disaster response agency.

Meanwhile in Palu, some 600 miles south of the volcano, it is not lava but water that concerns Oxfam the most. Hobbled by broken roads and damaged airports, the international aid organization says it is sprinting to scale up its efforts to get clean water to half a million people in need.

"The scale of the damage from the earthquake and tsunami is huge and there are fears many bodies are buried under collapsed houses and buildings," Oxfam's humanitarian manager in Indonesia, Ancilla Bere, said in a statement Thursday. "In many areas of Palu and surrounding towns, there is no running water and few working toilets — and sanitation is a serious concern."

NPR's Julie McCarthy described the brutal scene she confronted upon arriving in Palu.

"Lining the roads are small children. And they're chasing you, and they're asking for food. And they're holding up signs that say, 'We also need food. We, too, need food,' " McCarthy said.

"As you move into Palu, you see along the bay just nothing but houses that have been snapped like twigs," she added. "You see cement homes that are leaning into the bay. And every part of human existence is strewn among the debris."

But it is not just Palu that is suffering in the aftermath. McCarthy notes that other areas hit hard by the disaster, such as Donggala, have so far gotten less attention from aid groups than their larger counterpart — though that's not for lack of trying.

"Red Cross responders are pushing their way through debris and damaged roads to reach new areas and try to help the survivors, and they are finding devastation and tragedy everywhere," Iris van Deinse of the International Federation of Red Cross and Red Crescent Societies said in a statement Wednesday.

Van Deinse said she had been with an IFRC team that sought to bring supplies to the small village of Petobo, near Palu — only to discover that, for all intents and purposes, the village no longer even existed.

"When we arrived in Petobo, we found that it had been wiped off the map by the power of the tsunami," she explained.

There are some signs of hope. Heavy machinery and military transport aircraft have arrived for rescue efforts in Palu, and The Associated Press reports that workers have begun to rebuild the city's power grid.

Still, with more than 2,500 people injured and tens of thousands of buildings destroyed, authorities expect the death toll to climb further. And time is dwindling quickly for rescuers to find survivors.

"Any delay in a disaster costs lives," said Tim Costello of World Vision, "and there have been delays."</s>PALU, Indonesia — Wuhan is just 1, but her face already tells a story. When a 20-foot-high tsunami roared into Palu after an earthquake hit, it tore through everything in its path. Wuhan was swept into the water and disappeared for 24 hours.

It turns out Wuhan was trapped underneath the rubble in her family's beachfront neighborhood, which was destroyed by the tsunami. She was found surrounded by mud and underneath two dead bodies.

"I thank God because she has a new life," her mother Endang said.

But their story is one of the fortunate ones in the region. More than 70,000 people who survived the disasters are now homeless, many of them children living in makeshift tent camps. They have no running water or electricity and trash is overflowing and burning in the streets. They have used a river for drinking water and as a toilet.

"I don't know where to go," Endang said. "I no longer have a home."

Thankfully, help is finally arriving. The Indonesian military is beginning to distribute food, water and clothing. Endang was given instant noodles and water so she could finally feed her daughter. She's worried about the future but grateful that she still has the one thing she truly needs.</s>With some remote areas yet to be contacted and crews struggling to reach survivors, the death toll from Indonesia's earthquake and tsunami is expected to rise above 1,200 people.
The confirmed death toll from an earthquake and tsunami in Indonesia has risen to 1,407.