Illustrative file photo. - AFP
MEDAN: Two powerful earthquakes hit North Tapanuli regency in North Sumatra on Tuesday (March 18) morning, triggering a landslide that killed one person and injured one other.
The Meteorology, Climatology and Geophysics Agency’s (BMKG) director for earthquakes and tsunamis Daryono said the first earthquake struck at 5.22am with a magnitude of 5.5, followed by a second earthquake measuring 5.6 just 56 seconds later.
"The epicentres of both quakes were only 9km apart. These factors meet the criteria for what is known as a double earthquake," Daryono explained on Tuesday.
In seismology, a double earthquake refers to a sequence of two or more earthquakes of similar magnitudes, typically occurring within a short time frame. These earthquakes are sometimes triggered by the first earthquake's impact on nearby faults.
The epicentre of the twin earthquakes was located 17km from North Tapanuli, with a depth of 10km. They did not pose a tsunami risk.
The BMKG stated that the earthquakes were triggered by active seismic activity along the Sumatran Fault Line, specifically in the Toru Segment.
The Sumatran fault line is the longest in Indonesia, running the length of Sumatra Island from the northwest in Aceh to the south in Lampung, spanning a distance of 1,900km. Eight smaller magnitude aftershocks followed the twin earthquakes on Tuesday morning.
Another powerful earthquake hit in the early hours of Wednesday, prompting panic among residents of Simardangiang village, who rushed to flee their homes.
In response to the ongoing threat of aftershocks, Deputy North Tapanuli Regent Deni Lumbantontoruan temporarily closed schools in the regency until further notice.
Authorities reported that the earthquakes on Tuesday morning triggered a landslide that buried two houses in Hutabarat village, Pahae Julu district.
An elderly couple, 70-year-old Kartini Manalu and 67-year-old Hulman Hutabarat, were asleep in one of the houses when the landslide struck.
"Kartini lost her life, and Hulman sustained injuries. He has been taken to the Onanang Hasang Community Health Center [Puskesmas] for treatment," said North Tapanuli Police spokesperson, First Adj. Insp. Walpon Baringbing, on Tuesday.
The series of earthquakes also destroyed several houses and public facilities in Adiankoting district and Pahae Jae district, including five schools and one village head office.
"We are still evaluating the full extent of the earthquake's damage," Walpon stated. A 30-meter stretch of the trans-Sumatra Highway, which runs through Hutabarat village and Lobupining village, was buried under rocks, trees and debris up to 3m in depth after the earthquakes, completely blocking access to this crucial route.
The disaster also caused cracks along the highway near Silangkitang village.
Authorities cleared the blocked section by Wednesday morning, but the road is still limited to single-lane traffic due to the remaining mud. Police have implemented an open-close traffic system to manage the flow of vehicles.
Another earthquake with a magnitude of 4.8 struck Sukabumi regency and Cianjur regency in West Java on Tuesday afternoon, causing widespread panic as residents rushed out of their homes.
Asep Kusmanawijaya, acting head of the Cianjur Disaster Mitigation Agency, stated that officials are currently assessing the damage caused by the earthquake.
“We have not received any reports of significant damage so far. We urge residents to remain vigilant for aftershocks and avoid panicking,” he said on Tuesday, as reported by Antara.
“If you feel an earthquake, leave your house and find a safe location. Wait a few minutes before returning inside,” he added. - The Jakarta Post/ANN
