Will the big earthquake occur from the south of Java island to Bali?
Bandung,Indonesia -- Badan Meteorologi Klimatologi dan Geofisika (BMKG) said the earthquake sequence that occurred throughout August 2019 occurred in the subduction zone (Megathrust) extending from the West end of Sumatra to the south of Java, Bali, and Nusa Tenggara.
This subduction zone is called Sunda subduction bow. This significant earthquake activity spread from the Mentawai-Siberut Megathrust segment to the Megathrust segment of Sumba.
"The Sunda subduction bow is the same as the megathrust in the south of Java. Subduction from Aceh to Sumba is called Sunda subduction, " said Head of the field of mitigation of earthquake and Tsunami BMKG, Daryono, Tuesday (13/8) Daryono explained that BMKG monitoring showed that since early August 2019 there has been a barrage of earthquake acitivity in Sunda subduction bow.
"Beginning with the strong and damaging earthquake event in Banten magnitude M 6.9 on 2 August 2019 then, until 12 August the sequence of the earthquake still continue to shake. August 12 alone already twice the southern region of Bali and Banyuwangi is shaken an earthquake magnitude M 4.9, "he explained.
Daryono said the sequence of earthquakes since early August drew to be examined because it was wholly centered in the subduction zone. There is a variation of the epicenter depth as the source of the earthquake.
"There is indeed a variation in the depth of Hyposenternya, in which case there is a very shallow epicenter sourced in the subduction zone (front sub) but there are also the intermediate depths in the transitional zone between the Megathrust and Benioff zones," he said.
What is Megathrust?
Megathrust is a shallow part of a subduction strip that has a sloping angle, while the Benioff zone is part of a subduction column that has a steep angle of the hatchling.
"BMKG will continuously monitor seismic activity that occurs especially in the three active Duga zones and the result will be immediately informed to the community," he added.
Following the significant earthquake that occurred in the Sunda subduction bow which occurred since early August 2019:
1. August 2, 2019 Banten South earthquake M 6.9
2. August 3, 2019 Sukabumi earthquake M 4.4
3.3. 9 August 2019 earthquake Sumba M 4.3
4.10 August 2019 Earthquake Tasikmalaya and Pangandaran M 4.0
5.10 August 2019 Earthquake Tasikmalaya and Pangandaran M 5.1
6. August 11, 2019 the Pariaman earthquake M 5.2
7. August 11, 2019 the Southern Sunda Strait earthquake M 5.1.
8. August 12, 2019 South Bali earthquake and Banyuwangi M 4.9
