REPUBLIKA.CO.ID, JAKARTA -- At least 101 aftershocks jolted Lombok Island, West Nusa Tenggara Province, as of Monday at 11 a.m., following a 6.9-magnitude earthquake that rocked the island on Sunday evening (Aug 19). Of the total aftershocks, nine were felt by the local inhabitants of Lombok, according to information from the Meteorology, Geophysics and Climatology Agency (BMKG).
The agency also corrected the magnitude of the powerful earthquake into 6.9 on the Richter scale, from the early 7 reported. At least four people were killed and two others injured in the latest powerful earthquake on Lombok Island.
"The number was obtained based on the monitoring of North Lombok, East Lombok, Central Lombok, West Lombok, Mataram, and Sumbawa, following the quake," said I Gusti Lanang Wisnuwandana, spokesman of the Mataram Search and Rescue (SAR) office, in the capital city of West Nusa Tenggara, Monday.
Two of the casualties were found in West Sumbawa, one in East Lombok and another in Sumbawa, he said, adding that the two injured people were residents of East Lombok.
BMKG head Dwikorita Karnawati explained it was not an aftershock, but a new main shock. The epicenter was at 8.28 south latitude and 116.71 east longitude.
"By observing the epicenter, we can see it formed a new epicenter cluster, with the distribution heading eastward up to the north of West Sumbawa. So, we conclude that the earthquake is a new activity, which is different form the 7-magnitude quake that jolted West Nusa Tenggara province on August 5," Dwikorita said in a press conference at her office on Sunday (Aug 19) night.
The epicenter was some 30 km northeast of East Lombok District and at a depth of 10 km. The earthquake, with VII MMI (Modified Mercalli Intensity), was felt strongly by inhabitants of East Lombok, North Lombok, West Sumbawa, Sumbawa Besar, and Mataram. It lasted for 5 to 10 seconds.
Inhabitants of Bali, Jember in East Java, and Makassar in South Sulawesi also felt the tremor. Many Lombok inhabitants rushed out of buildings in a panic, as there were also a power outage and landslides on Mt Rinjani slope following the earthquake.
Following the powerful quake, Lombok was jolted by frequent aftershocks at magnitudes ranging between 5.0 and 5.8 on the Richter scale.
On the same evening, a fire broke out on Bungin Isle, Sumbawa, West Nusa Tenggara. The cause of the fire is not yet known. Bungin is a very crowded isle.
Earlier in the day, earthquakes of magnitudes 5.4 and 6.5 jolted Lombok Island at 12:06 and 12:10 local time (WITA), respectively. On August 5, 2018, Lombok Island was devastated by a 7-magnitude earthquake that killed some 460 people.