Antara 4 Oct 18;
Jakarta (ANTARA News) - Some 3.8 million Indonesians run the risk of tsunami threat, Chief of the Information Data and Public Relations of the National Disaster Mitigation Agency (BNPB) Sutopo Purwo Nugroho stated on Wednesday.
"We only have 30-40 minutes to save ourselves. Hence, tsunami mitigation is important," he noted at a press conference related to a powerful magnitude 7.4 earthquake and a subsequent tsunami in Central Sulawesi Province.
When a magnitude 7.8 earthquake, which triggered a 36-meter-high tsunami, struck the island of Flores on December 12, 1992, and left about 2,600 people dead and missing, the time span between the earthquake and the tsunami was only five minutes, he noted.
The time span is relatively short since tsunamis in Indonesia have local characteristics. This means the source of the earthquake triggering a tsunami is found around the Indonesian territory, he noted.
"The eastern part of Indonesia is more vulnerable. However, lack of research, infrastructure facilities, awareness, and tsunami mitigation (remain a problem)," he pointed out.
He remarked that 2,243 people were killed when a tsunami measuring 50 to 100 meters high engulfed the Maluku provincial capital of Ambon in 1674.
"Between 1629 and 2018, Central Sulawesi bore witness to 176 large and small tsunamis," he noted.
Meanwhile, 148.4 million of the 265 million population of Indonesians run the risk of earthquake threat.
A magnitude 7.4 earthquake rocked Palu City and Donggala District in Central Sulawesi last Friday (Sept 28). The earthquake was centered 27 kilometers northeast of Donggala at a depth of 10 kilometers.
Reporting by Dewanto Samodro
Editing by Suharto, Fardah Assegaf
Editor: Heru Purwanto
Geology agency to map Indonesia`s disaster-prone areas
Antara 4 Oct 18;
Head of the Geology Agency at the Ministry of Energy and Mineral Resources, Rudy Suhendar. (ANTARA /Sigid Kurniawan)
Jakarta (ANTARA News) - The Head of the Geology Agency at the Ministry of Energy and Mineral Resources, Rudy Suhendar, said the agency is trying to map Indonesia`s territories with high disaster potentials.
"Basically, from Sumatra, Java, Bali, Nusa Tenggara, and Maluku to Papua, all of them have the potentials for disasters, commonly earthquake because they are located on a long fault line," Suhendar said here Wednesday.
However, according to him, the intensity of earthquake is different between one area and another depending on the geological conditions of each place. People are expected to monitor the fault lines and find out if their area is directly traversed by the faults.
"The map on fault lines can be seen on the geology page of the Ministry of Energy and Mineral Resources. If we know these fault lines in advance, disaster mitigations can be done; for instance, by not building houses with heavy materials," he stated.
Suhendar explained that time, location, and magnitude of an earthquake cannot be predicted. "So far, what can be predicted from an earthquake is its maximum magnitude, potential, and intensity," he explained.
"Regarding the earthquake and tsunami that occurred in Palu and Donggala, let us all pray there would be no more major earthquakes. However, people are expected to remain vigilant about aftershocks. People should also keep following the directives from authorized institutions and not believe any news from unclear sources," Suhendar added.
The cause of earthquakes in Indonesia comes from subduction zones and active faults on land. The subduction zones stretch from west of Sumatra Island, south of Java Island, south of Bali, and Nusa Tenggara and turn to Maluku Islands to form sea trenches.
Subduction zones can also generate to form tsunami.
The active faults on lands include the Sumatran Fault, which extends from north to south on Sumatra Island. In Java Island, there are Cimandiri Fault, Lembang Fault, Baribis Fault. and Opak Fault.
"Besides that, there are Flores Back Arc Faults in North Nusa Tenggara Islands, Palu-Koro Fault in Central Sulawesi, Tairura-Aiduna Fault, Sorong Fault, and others," he noted.
Earthquake still cannot be predicted. However, there are some efforts that can be made, including delineating active tectonic areas that generate earthquakes, estimating the return period of the earthquakes, determining the parameters of each earthquake, and calculating maximum potentials.
The Geology Agency continues to make efforts to mitigate disasters by mapping areas that have been hit by tsunami. The maps are presented in maps of earthquake- and tsunami-prone areas.
The Map of Disaster-Prone Areas of Earthquakes and Tsunamis are routinely socialized to all local administrations.
Regarding the earthquakes that hit Central Sulawesi province, the Geological Agency has made the Map of Earthquake-Prone Areas of Central Sulawesi, Map of Earthquake and Tsunami-Prone Areas of Palu Bay, and Microzonation Map of Palu Earthquake.
"All parties must be alert and ready to face earthquakes and tsunami that could take place in any place and at any time. Spatial planning should be made by considering the disaster potentials, and all buildings and infrastructures must consider seismic aspects. These are some of the mitigation efforts to reduce risks of geological disasters," he pointed out.
Reporting by Afut Syafril Nursyirwan
Editing by Libertina, Yoseph Hariyadi
Editor: Heru Purwanto
Mt. Gamalama in North Maluku erupts, residents told to stay away
The Jakarta Post 4 Oct 18;
The Volcanology and Geological Hazard Mitigation Center (PVMBG) has raised the status for Mount Gamalama in North Maluku to caution -- the second after normal in the four-level national volcano alert system -- on Thursday following an eruption at 11:52 a.m. local time.
The eruption, which saw a-250 meter column of ash spew from the mountain’s crater, had been preceded by at least eight tremors, said the PVMBG.
“We suggest that residents and visitors steer at least 1.5 kilometers clear of the volcano,” the agency said in a statement, adding that residents living near rivers around the mountain should also be cautious of potential lava flows.
Three volcanoes are currently active in Indonesia, namely Mt. Anak Krakatau in Lampung, Mt. Soputan in North Sulawesi and Mt Gamalama. Mt. Soputan erupted on Wednesday morning, while Mt. Anak Krakatau erupted more than 150 times on Tuesday. (vny)
