JAKARTA, Dec 10 (Jakarta Post/ANN): On Thursday morning, a 5.8-magnitude earthquake rocked Sukabumi in West Java, sparking a panic among residents barely awake in and around the city.
It was the fifth significant tremor to hit the province in the past month. Suddenly the region has to contend with the possibility of more seismic activity in the near future, prompting experts to call for more preemptive measures by the government.
Pramono, 28, a local resident of Sukabumi’s Cikole district, said the shocks immediately woke him up from his sleep as the trembling went on for a few seconds.
“The shaking felt quite strong,” said the young man who lives on the second floor of a boarding house, as quoted by Kompas.com.
The Meteorological, Climatological and Geophysical Agency (BMKG) later reported that the earthquake’s epicenter was located 22 kilometers southeast of the city and 104 km below the surface.
In spite of this, the shocks could be felt more than 100 km away in the urban sprawl of Jakarta, with footage circulating on social media showing people scrambling out of the capital’s skyscrapers.
Less than a week before that, a 6.4-magnitude earthquake hit West Java’s Garut regency, with an epicenter located 118 km below the surface. One person was injured and four houses were damaged as a result, the National Disaster Mitigation Agency (BNPB) reported.
ore than 300 people have lost their lives in its wake, making it the deadliest earthquake in the country in the past four years.
The tremors also forced tens of thousands of local residents to seek shelter in evacuation tents, with around 53,000 houses left in various stages of damage.
A day before the Cianjur tragedy, a 5.3-magnitude quake with an epicenter 24 km below the surface was reported in the Pangandaran regency and another 5.3-magnitude earthquake hit Garut a week before that.
More to come While West Java has been known to be particularly prone to earthquakes due to the numerous tectonic fault lines that crisscross the province, Bandung Institute of Technology (ITB) geologist Heri Andreas said that the recent string of movements was “out of the ordinary.”
“An earthquake with a magnitude greater than five usually happens only once or twice a year in West Java. Now, it has happened a handful of times just in the span of one month,” Heri told The Jakarta Post on Thursday.
Yonvitner, head of the Bogor Agricultural University’s (IPB) center for disaster studies, said the frequency of tectonic movements in recent weeks suggested that more activity may come in the weeks ahead, particularly around West Java’s active Cugenang and Lembang faults.
“While earthquakes are an inevitable natural occurrence, this is a trend that we need to pay particular attention to in order to integrate it into our [disaster] early warning systems,” Yonvitner told the Post on Thursday, noting that disasters are a common occurrence toward the year’s end.
Heri suggested that the recent string of earthquakes could be part of a 200-year tectonic cycle that usually culminated in a major quake hitting the country’s southern coastline in the coming decades, as part of the seismically active Pacific Ring of Fire.
“There are examples, like the 1994 Banyuwangi quake and the 2004 Aceh quake. These are pockets of areas that have seen a release in tectonic pressure underground.
The southern shore of West Java, however, has not yet experienced this, meaning that pressure is still building up,” Heri said.
Necessary precautions With the threat of more earthquakes looming, Heri has called on the government to focus on pre-disaster mitigation measures rather than disaster response.
“[The government] should build more evacuation routes and shelters, particularly along the shores, as part of its structural mitigation efforts,” he said.
“The public, meanwhile, should receive more drills and education to help prepare them for natural disasters.”
Separately, head of the BMKG earthquake and tsunami mitigation division, Daryono, said that structural and nonstructural disaster mitigation measures are now more important than ever, particularly with the rising frequency of earthquakes since 2018.
“In 2018, there were 11,000 instances of earthquakes [nationwide], whereas previously [the yearly average] was around 5,000,” he said at a press briefing on Thursday.
“As of December, there have already been 11,000 earthquakes this year,” he said. It also coincided with a rise in the number of earthquakes that caused a significant number of casualties and property damage, he added.
“There are usually around eight to 10 instances of destructive earthquakes occurring annually. Since 2018, this number has risen to between 15 to 20,” Daryono said. – Jakarta Post/ANN
