By Indonesia correspondent Samantha Hawley
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MAP: Bali
Bali's Governor has urged people to remain calm amid fears of a volcanic eruption on the holiday island.
Seismic activity at the Mount Agung, or Gunung Agung, volcano significantly increased on Monday, leading authorities to issue a level 3, or high, alert and evacuate areas within 7.5 kilometres.
"We see that the earthquake frequency is very high, this is worrying when it comes to eruption," said Kasbani, the head of the Centre for Volcanology and Geological Hazard Mitigation.
"The areas should be closed, no hiking because the seismic activity will trigger dangerous gas."
Mount Agung is a popular hiking spot for foreign tourists.
Kasbani said no volcanic ash had been detected but smoke was rising from the crater. The alert level would be raised to 4, or dangerous, if it became clear an eruption was imminent.
The volcano last erupted in 1963, emitting ash 10 kilometres high and killing more than a thousand people.
Bali's Governor tried to reassure worried locals that all measures were in place to cope with a possible eruption.
"This is a natural disaster, we cannot avoid it, we can't stop it exploding but we can reduce the number of victims and loses," Made Mangku Pastika said.
"If you have to evacuate, you evacuate."
He said authorities had prepared locations for residents to store motorbikes, cars and even livestock to reduce losses.
"We are prepared, I believe we can handle everything," the Governor said.
There has been no impact on flights in and out of Bali.
The Governor said tourists should follow advice from officials and hotel staff.
Topics: volcanic-eruption, disasters-and-accidents, travel-health-and-safety, bali
Bali News and Views Editor's Comments -
Do you need to worry about the current possible eruptions on Bali's Mount Agung?
Monday night one of our staff , who lives not too far from Mount Agung said she couldn't sleep because she felt 30 or 40 tremors around Mount Agung and she was afraid that it was going to erupt.
Although we couldn't feel these tremors 40 km away at my home on the beach I was concerned for the welfare of others within a close proximity to Agung.
Many locals died because they did not not have Mobile phones, Facebook or Twitter to keep them advised of the latest warnings.
As can be seen on this chart is the actual flows of different categories in 1963 including the actual lava, the faster and more dangerous Pyroclastic Flow and Lahar Flows.
Today I am starting to see some of the news coming out in the world news as per below. I know from past events they will spin it out of sight. Bad news makes good press. The press will make it look like Bali is about to explode.
Having lived in Bali for 21 years and seeing Mount Agung almost every day plus having lived in Hawaii for an additional eighteen years I can tell you that volcanoes are blown way out of proportion. Pardon the pun.
As a former Yacht Capt. in Bali for five years I'm very familiar with the Tradewinds at this time of the year.
The only thing we can learn from history is we may be doomed to repeat it.
Hopefully we are not doomed to repeat the disastrous 1963 volcano eruption that took thousands of lives, primarily because the locals did not have any information at the time.
Today we have very modern reporting by the Bali government who are right on top of the situation changing the warning levels to suit the activity of the volcano.
I just spent the last two hours patching together past flows, including Pyroclastic flows, which are the worst because they come quickly and kill people immediately.
I've also included traditional trade wind patterns based on my observations as a yacht Captain and beachfront home owner the last 21 years.
It important to note that this a very rough sketch prepared in a hurry and is not scientific.
The reason I'm not concerned, although I live within 30 km from this volcano, is the fact that the Tradewinds this time the year are flowing from East to West.
Therefore, any Pyroclastic flows, which are the most dangerous consisting primarily of gas, should be blown away from where I live, and in fact from the entire southern Bali area where 90% of the population and tourists reside.
So before the press spins this way out of context take a look at the chart yourself, use common sense and don't panic.
Tourists coming to Bali, most likely have nothing to fear.
In fact Tourists may be provided with a rare once in a lifetime view of a live volcano.
I have personally walked on top of lava on the big Island of Hawaii and it is not as scary as it seems.
All you scientific nuts please be aware that none of this information, including the chart is proven scientific knowledge and only to be used as a general understanding of what's going on. So keep your skepticism to yourself.
On the other hand, your welcome to make valid comments.
1963-64 Mount Agung Eruption
On February 18, 1963, local residents heard loud explosions and saw clouds rising from the crater of Mount Agung.
On February 24, lava began flowing down the northern slope of the mountain, eventually traveling 7 km in the next 20 days.
On March 17, the volcano erupted (VEI 5), sending debris 8 to 10 km into the air and generating massive pyroclastic flows.
These flows devastated numerous villages, killing approximately 1500 people.
Cold*lahars caused by heavy rainfall after the eruption killed an additional 200. A second eruption on May 16 led to pyroclastic flows that killed another 200 inhabitants.
The lava flows missed, sometimes by mere yards, the Mother Temple of Besakih. The saving of the temple is regarded by the Balinese people as miraculous and a signal from the gods that they wished to demonstrate their power but not destroy the monument the Balinese faithful had erected.
Andesite was the dominant lava type with some samples mafic enough to be classified as basaltic andesite.
*Lahar is an Indonesian term that describes a hot or cold mixture of water and rock fragments that flows down the slopes of a volcano and typically enters a river valley. Small seasonal events are sometimes referred to as "debris flows", especially in the Cascades.
Gunung Agung 1963 Eruption
The February 1963 to January 1964 eruption of Gunung Agung, Indonesia’s largest and most devastating eruption of the twentieth century, was a multi-phase explosive and effusive event that produced both basaltic andesite tephra and andesite lava.
A rather unusual eruption sequence with an early lava flow followed by two explosive phases, and the presence of two related but distinctly different magma types, is best explained by successive magma injections and mixing in the conduit or high level magma chamber.
The 7.5-km-long blocky-surfaced andesite lava flow of ∼0.1 km3 volume was emplaced in the first 26 days of activity beginning on 19 February.
On 17 March 1963, a major moderate intensity (∼4 × 107 kg s−1) explosive phase occurred with an ∼3.5-h-long climax.
This phase produced an eruption column estimated to have reached heights of 19 to 26 km above sea level and deposited a scoria lapilli to fine ash fall unit up to ∼0.2 km3 (dense rock equivalent—DRE) in volume, with Plinian dispersal characteristics, and small but devastating scoria-and-ash flow deposits.
On 16 May, a second intense 4-h-long explosive phase (2.3 × 107 kg s−1) occurred that produced an ∼20-km-high eruption column and deposited up to ∼0.1 km3 (DRE) volume of similar ash fall and pyroclastic flow deposits, the latter of which were more widespread than in the March phase.
The two magma types, porphyritic basaltic andesite and andesite, are found as distinct juvenile scoria populations.
This indicates magma mixing prior to the onset of the 1963 eruption, and successive injections of the more mafic magma may have modulated the pulsatory style of the eruption sequence.
Even though a total of only ∼0.4 km3 (DRE volume) of lava, scoria and ash fall, and scoria-and-ash pyroclastic flow deposits were produced by the 1963 eruption, there was considerable local damage caused mainly by a combination of pyroclastic flows and lahars that formed from the flow deposits in the saturated drainages around Agung.
Minor explosive activity and lahar generation by rainfall persisted into early 1964.
The climactic events of 17 March and 16 May 1963 managed to inject ash and sulfur-rich gases into the tropical stratosphere.
The 1963–1964 eruption of Agung volcano (Bali, Indonesia).
Available from: https://www.researchgate.net/publication/257428344_The_1963-1964_eruption_of_Agung_volcano_Bali_Indonesia [accessed Sep 19, 2017].
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