7.4 Earthquake in Flores Sea Explained

TheIndonesia.id - Head of the Meteorology, Climatology, and Geophysics Agency (BMKG) Dwikorita Karnawati affirmed that the earthquake that hit Flores Sea was a shallow quake caused by a strike-slip fault in the area.

The agency had revised the magnitude of the earthquake, from 7.5 to be 7.4.

"Taking into account the location of the epicenter and the depth of the hypocenter of the earthquake, it was a shallow earthquake," the agency head informed during a virtual press conference reported by Antara news agency on Tuesday, December 14, 2021.

Karnawati noted that the agency’s analysis showed that the earthquake, which struck 112 kilometers (km) northwest of Larantuka Sub-district, East Flores District, East Nusa Tenggara (NTT) Province, at 10:20 Western Indonesia Standard Time (WIB), was triggered by a strike-slip fault.

The shock was felt in the Ruteng Sub-district, Labuan Bajo Village, Larantuka Sub-district, Maumere Sub-district, Adonara Sub-district, and Lembata District, with an intensity of III-IV of Modified Mercalli Intensity (MMI).

In addition, the residents of Tambolaka, Waikabubak, and Waingapu sub-districts sensed the shock at an intensity of III MMI.

The MMI III shock was usually felt by people indoors akin to a passing truck. Meanwhile, the MMI IV shock can cause windows, doors, and walls to make cracking sounds.

However, the BMKG had not received any reports of damage caused by the disaster.

Furthermore, the earthquake also triggered an early warning for tsunami for the provinces of East Nusa Tenggara (NTT), West Nusa Tenggara (NTB), South Sulawesi, Southeast Sulawesi, and Maluku.

The agency had noted that the tsunami wave had arrived in Marapokot Village, Nagekeo District, at 10:36 WIB and Reo Sub-district, Manggarai District, at 10:39 WIB, with a height of seven centimeters (cm).

The BMKG had revoked the tsunami early warning two hours after the first earthquake occurred.

"In addition, the sea level rise has not been detected anymore,” Karnawati added.

However, Karnawati urged the public to stay vigilant of likely aftershocks. At the press conference, she informed that 20 aftershocks occurred following the 7.4-magnitude earthquake.

BMKG reported that 15 aftershocks occurred following the 7.5 magnitude earthquake that happened in the Flores Sea, East Nusa Tenggara Province on Tuesday morning local time.

“As of Tuesday at 11:40 a.m. Western Indonesia Standard Time (WIB), there have been 15 aftershocks with a maximum magnitude of 5.6," Head of the BMKG’s Earthquake and Tsunami Center Bambang Setiyo Prayitno.