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Information message about a strong earthquake on the coast of Flores Island, Indonesia, on August 14, 2026.

An earthquake (devastating at the epicenter on the SIS-17 scale) with M=7.4 occurred on August 14, 2026 at 21:58 Greenwich Time (August 15 at 00:58 Moscow Time) on the northern coast of Flores Island, Indonesia..<br /> SIS-17 - Earthquakes. Seismic intensity scale. State Standard 57546–2017.

Parameters of the earthquake have been determined in the Alert Service (AS) of Information Processing Center (IPC) of Geophysical Survey of RAS in Obninsk with station data obtained from digital and analog seismic stations of Russia, countries of CIS and from abroad. Alert message on this earthquake has been delivered in 13 min after registration to the Ministry of Emergency of the Russian Federation (EMERCOM).

Preliminary processing has been done with data from 18 stations, accurate processing - with data from 58.

The red marker on the map is the epicenter of the earthquake, its origin was located on the northern coast of the island of Flores in the Indonesian province of East Nusa Tenggara at a depth of 10 km, 49 km NE of Banjawa, 50 km NW of Ende Timur, 156 km E of Labukhanbanjo.

	Time in origin (GMT)	Latitude, degree	Longitude, degree	Depth, km	Stations number	Ms/N	mb/N	I0 (calculated)	GAP	Center
1	21:58:20.0	-8.5	121.31	10.0	58	7.4/48	6.9/42	10.5-11	69	GS RAS(Verified) Federal research center, Geophysical survey of Russian Academy of Sciences
2	21:58:36.7	-8.77	121.09	160.0	18		6.1			GS RAS(Preliminary) Federal research center, Geophysical survey of Russian Academy of Sciences
3	21:58:24.1	-8.37	121.36	20.0	720	7.7 Mw	6.6/327		12	CSEM European - Mediterranean seismological center
4	21:58:22.6	-8.31	121.35	0.0	107	7.7 Mw/92	6.8/263		36	NEIC National Earthquakes Information Center of US Geological Service

Fig. 1 presents fragments of records obtained from digital stations Kappang (∆ 3.8º), Davao City (∆ 16 º), Tennant Creek (∆ 17º), Port Moresby (∆ 25.5º), Kunigami (∆ 35.8º). Fig. 2 presents fragments of records obtained from digital stations Matsushiro (∆ 47.5º), Mys Shultsa (∆ 51.6º), Vladivostok (∆ 52.3º), Erimo (∆ 54.1º), Yuzhno-Sakhalinsk (∆ 58.4º).

Image 1

Image 2

GS RAS registered 18 aftershocks with М>=4.9 within 12.5 hours after the main shock.

N	Time in origin (GMT)	Latitude, degree	Longitude, degree	Depth, km	Stations number	Ms/N	mb/N	I0 (calculated)	Region
20263514	14/08/2026 22:13:49.0.0	-8.28	120.12	10.0	80		6.0/71	7.5-8	Flores region, Indonesia
20263515	14/08/2026 22:28:40.0.0	-8.01	121.79	10.0	49		6.2/39	8-8.5	Flores region, Indonesia
20263519	14/08/2026 22:37:18.0.0	-8.08	120.3	10.0	29		5.6/25	6.5-7	Flores region, Indonesia
20263516	14/08/2026 22:53:13.0.0	-8.13	120.17	10.0	52		5.5/33	6.5-7	Flores region, Indonesia
20263520	14/08/2026 23:12:31.0.0	-8.07	120.79	10.0	17		5.2/16	5.5-6	Flores region, Indonesia
20263521	14/08/2026 23:17:06.0.0	-8.27	121.6	10.0	13		5.1/12	5.5-6	Flores region, Indonesia
20263523	15/08/2026 01:17:20.0.0	-8.0	120.7	10.0	21		5.2/17	5.5-6	Flores region, Indonesia
20263524	15/08/2026 01:37:40.0.0	-8.17	120.28	10.0	27		5.2/25	5.5-6	Flores region, Indonesia
20263525	15/08/2026 02:18:48.0.0	-8.04	121.72	10.0	19		4.9/16	5-5.5	Flores region, Indonesia
20263526	15/08/2026 02:46:55.0.0	-8.27	121.49	10.0	20		5.1/15	5.5-6	Flores region, Indonesia
20263527	15/08/2026 03:54:14.0.0	-8.03	121.66	10.0	21		5.2/18	5.5-6	Flores region, Indonesia
20263539	15/08/2026 04:23:08.0.0	-8.42	121.37	10.0	19		5.0/10	5-5.5	Flores region, Indonesia
20263528	15/08/2026 05:45:07.0.0	-8.47	121.49	10.0	19		5.0/16	5-5.5	Flores region, Indonesia
20263529	15/08/2026 06:28:49.0.0	-8.46	121.48	10.0	21		5.1/19	5.5-6	Flores region, Indonesia
20263530	15/08/2026 06:43:06.0.0	-8.34	120.48	10.0	21		4.9/16	5-5.5	Flores region, Indonesia
20263531	15/08/2026 07:39:38.0.0	-8.02	120.94	10.0	26		5.1/23	5.5-6	Flores region, Indonesia
20263532	15/08/2026 09:32:53.0.0	-8.29	121.69	10.0	24		5.0/21	5-5.5	Flores region, Indonesia
20263546	15/08/2026 10:31:31.0.0	-8.15	120.48	10.0	17		5.3/15	6-6.5	Flores region, Indonesia

According to TASS The death toll from the devastating earthquake in Indonesia has reached 72, with more than 900 injured. 82,691 people were forced to flee their homes. The earthquake destroyed more than 900 buildings, and 29000 were damaged.
A magnitude 7.7 earthquake struck the Indonesian province of East Nusa Tenggara on Saturday. Residents along the coast of Flores Island were advised to evacuate from their homes and stay at least 2 kilometers far from the coast line due to the threat of a tsunami. According to the Jakarta Globe, government and residential buildings, schools, medical institutions, and religious institutions were damaged on the island.
Figure 1 was obtained from USGS NEIC , it presents USGS Community Internet Intensity Map made by 42 responses from 17 sites.

Image 1

Click here to view detailed macroseismic data (DyfitWeb service)

Focal mechanism solution of the origin was calculated by GS RAS with signs of initial arrivals of P waves at 88 stations, including 74 stations which registered compression waves (plus signs), and 14 stations which registered tensile waves (minus signs). The stations are located in the interval of epicentral distances 1-100 º and in azimuth sector Az=0-359º. Focal mechanism solution in stereographic projection on the lower hemisphere and elements of the mechanism are presented in the table. The table also contains focal mechanism solutions obtained at the USGS NEIC with WW-phase Moment Tensor (Mww) technique and in Lamont-Dohert Earth Observatory of Columbia University, USA (LDEO GCMT) with СМТ (Centroid moment tensor) technique. Solutions from different centers are close.. The earthquake was caused by predominantly north-oriented compression stresses (AZ=0-8, 360º). One nodal plane NP1 strikes west (STK=267-279º), another plane NP2 strikes east (STK=90-97º). Both planes are dipping at the same angle (DP=45º) according to GS RAS, and NP2 is dipping more horizontally (DP=32-33º) if compared with NP1 (DP=58º) according to USGS NEIC and LDEO GCMT. The type of motion along both planes – reverse fault. The seismic moment according to USGS NEIC makes Mo=5.501 *10**20 N*m, Mww=7.8. According to LDEO GCMT it makes Mo=5.53*10**20 N*m, Mw=7.8.

Axes of main strengths			Nodal planes		Center
T	P	N	NP1	NP2	Center
PI: 89 Azm: 278	PI: 0 Azm: 8	PI: 1 Azm: 98	Stk: 279 Dp: 45 Slip: 92	Stk: 97 Dp: 45 Slip: 88	GS RAS Federal research center, Geophysical survey of Russian Academy of Sciences
PI: 77 Azm: 179	PI: 13 Azm: 360	PI: 0 Azm: 270	Stk: 269 Dp: 58 Slip: 90	Stk: 90 Dp: 32 Slip: 90	NEIC National Earthquakes Information Center of US Geological Service
PI: 77 Azm: 165	PI: 13 Azm: 0	PI: 3 Azm: 269	Stk: 267 Dp: 58 Slip: 86	Stk: 94 Dp: 33 Slip: 96	GCMT Lamont-Doherty Earth Observatory Global CMT Columbia University, USA

According to USGS NEIC The August 14, 2026, M7.7 Flores Sea earthquake occurred off the northern coast of East Nusa Tenggara, Indonesia, as the result of reverse faulting at shallow depth. The earthquake is located in a seismically active area dominated by convergence between the Australia and Sunda plates. Focal mechanism solutions indicate that the rupture occurred on either a west-striking fault dipping moderately to the north or an east-striking fault dipping shallowly to the south. The location, depth, and preliminary focal mechanism solution for this earthquake indicate the event is likely the result of thrust faulting within the overriding Sunda plate. At the location of this earthquake, the Australian plate is moving towards the north with respect to the Sunda plate at approximately 69 mm/yr. These two plates meet at the Sunda Trench, located approximately 350 km south of this earthquake. While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Reverse-faulting events of the size of the August 14, 2026, earthquake are typically about 90 by 45 km in size (length x width). Earthquakes are common in this region. Since 1950, there have been 37 other earthquakes of magnitude 6 and greater, including five other earthquakes of magnitude 7 and larger within 250 km of the August 14, 2026, earthquake. In 1992, a M7.8 earthquake occurred just 63 km east-southeast of the August 14, 2026, earthquake. The 1992 earthquake and resulting tsunami destroyed tens of thousands of homes and resulted in at least 2500 fatalities.