Volcanoes
"Eight deep volcanic quakes and one surface quake were recorded between Oct. 25 and 31," Mt. Dempo observation post chief Slamet said.
He said Mt. Dempo was different to other volcanoes in Indonesia, particularly because of its wide and vast crater.
"This means there can be changes in its volcanic activity at any time," Slamet said.
Dempo erupted in 1838, creating a lava lake covering an area of around 3,000 square meters.
Despite that only volcanic tremors had been recorded, Slamet said, residents living on Dempo's slopes needed to be on the alert because of its unpredictable nature.

Passengers enter a terminal as an information screen shows cancelled international flights at Soekarno-Hatta International Airport in Jakarta, Indonesia, Saturday, Nov. 6, 2010.
The number of people killed by Mount Merapi in the past two weeks climbed to 138, as a tiny hospital at the foot of the mountain struggled to cope with survivors, some with burns on up to 95 per cent of their bodies.
The only sign of life in one man, whose eyes were milky grey in colour and never blinked, was the shallow rising and falling of his chest. Others, their lungs choked with abrasive volcanic ash, struggled to breathe.
Indonesia's most volatile mountain unleashed a surge of searing gas, rocks and debris Friday that raced down its slopes at highway speeds, mowing down the slope-side village of Bronggang and leaving a trail of charred corpses in its path.

Mount Merapi volcano spews smoke as seen from Sidorejo village in Klaten, near the ancient city of Yogyakarta, on Nov. 3. The latest eruption was the biggest yet, causing evacuees to move their shelters even further from the mountain.
Men with ash-covered faces streamed down Mount Merapi on motorcycles followed by truckloads of women and crying children, following the massive eruption just before midnight Friday.
Even staff at the mountain's main monitoring post were told to move farther from the glowing crater.
Hospital spokesman Heru Nugroho said 48 bodies were brought in after the inferno. More than 65 others were injured, many of them critically.

Mount Merapi volcano spews smoke as seen from Deles village in Klaten, near the ancient city of Yogyakarta.
No casualties were reported in Mount Merapi's new blast, which came as Indonesia struggles to respond to an earthquake-generated tsunami that devastated a remote chain of islands. The two disasters unfolding on opposite ends of the country have killed nearly 500 people and strained the government's emergency response network. In both events, the military has been called in to help.
Soldiers loaded men, women and crying children into trucks as rocks and debris hurled in the air and down the mountain's slopes. No new casualties were reported immediately after the booming explosion that lasted more than an hour.
"This is an extraordinary eruption, triple from the first" on Oct. 26, said Surono, a state volcanologist.
A week after Indonesia's most active volcano began shooting searing gas clouds from its crater, restless evacuees say they are tired of living in hot, cramped shelters. But repeated explosions signal that the volcano, known here as "Fire Mountain," is not ready to let them go home.
Continued blasts have not deterred many families from heading back up the mountain. They go to check on their homes and cattle. At night, they return, packing into overcrowded camps to sleep on thin mats among thousands.
Klyuchevskaya Sopka, Eurasia's highest active volcano which stands 4,750 meters (15,584 feet) high, started to spew ash on Ust-Kamchatsk on October 22.
Also Sopka Shiveluch began erupting on Thursday spewing ash approximately 6 miles into the air and the streaming down of lava.
More than 5,000 townspeople were forced to stay at home with their windows shut, while all public institutions, schools and businesses remained closed.

Mount Merapi volcano as seen from Balerante village in Klaten, Indonesia, 29 October Mount Merapi is the most active of Indonesia's volcanoes
The latest eruption happened at around 0100 on Saturday (1800GMT Friday).
Agence France Presse reported that it caused panic, with hundreds of people, including police and soldiers, trying to flee in cars or on motorbikes.
Ash was raining down in Yogyakarta, about 30km (19 miles) away.
Matt Burgess, a photography student from Australia, is in Yogyakarta. He told the BBC: "I was in a nightclub when a friend called to say there was a load of ash. I went outside and saw ash falling like snow."
But authorities say Yogyakarta is safe. The head of the monitoring body has said the risk remains lmited to the 10km zone around the mountain.
Nearer that zone, though, people felt more in danger.

Mount Merapi is seen emitting smoke from Sidorejo village, in Klaten, Central Java October 28, 2010, two days after its eruption.
There were no immediate reports of new casualties after Merapi's second eruption. More than 40,000 people had fled or been evacuated from Merapi's slopes earlier in the week, but many started to return after the volcano appeared to become calmer.
Officials said the death toll from a tsunami that hit the remote western Mentawai islands on Monday had reached at least 343. The tsunami was triggered on Monday by a 7.5 magnitude quake. A day later, Mount Merapi on the outskirts of Yogyakarta city on Java island erupted, killing at least 34.
Hot ash rained down from the smoke-covered crater, injuring at least 20 people.
"We heard three explosions around 06:00 pm (1100GMT) spewing volcanic material as high as 1.5 kilometres and sending heat clouds down the slopes," government volcanologist Surono told AFP.
Before the latest eruption, people living in the shadow of Indonesia's most active volcano had been warned to evacuate or risk being killed.
Authorities had put an area 10 kilometres around the crater of Mount Merapi on red alert Monday, ordering 19,000 people to flee.
"This eruption is certainly bigger than the 2006 eruption during which the heat clouds occurred for only seven minutes after the eruption," Surono said.








