Mag. 4.9 earthquake - Tonga (Samoa) on Friday, 21 July 1978 at 07:22 (GMT)

Mag. 4.9 earthquake - Tonga (Samoa) on Friday, 21 July 1978 at 07:22 (GMT)

Light magnitude 4.9 earthquake at 33 km depth

Date & time: 21 Jul 1978 07:22:36 UTC
Magnitude: 4.9
Depth: 33.0 km
Epicenter latitude / longitude: 15.298°S / 173.168°W (Samoa)
Nearest volcano: Curacoa (65 km / 40 mi)
Nearby towns and cities:
99 km (62 mi) NE of Hihifo (Tonga) (pop: 815) --> See nearby quakes!
195 km (121 mi) SSW of Vailoa (pop: 769) --> See nearby quakes!
204 km (126 mi) SW of Mulifanua (pop: 4,510) --> See nearby quakes!
206 km (128 mi) SSW of Asau (pop: 6,640) --> See nearby quakes!
212 km (132 mi) SW of Fasito‘outa (pop: 2,100) --> See nearby quakes!
221 km (138 mi) SSW of Safotu (pop: 1,210) --> See nearby quakes!
222 km (138 mi) SW of Apia (pop: 40,400) --> See nearby quakes!
232 km (144 mi) SW of Lufilufi (pop: 1,070) --> See nearby quakes!
284 km (177 mi) WSW of Tāfuna (Tualauta, American Samoa) (pop: 11,000) --> See nearby quakes!
288 km (179 mi) WSW of Pago Pago (Ma'Oputasi, American Samoa) (pop: 11,500) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 1.4 x 1012 joules (392 megawatt hours, equivalent to 338 tons of TNT) More info
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Data for the same earthquake reported by different agencies

Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.
MagnitudeDepthLocationSource
M 4.933 kmTonga (Samoa)USGS
Note: for quakes of 2012 and earlier, our database often contains only records from USGS.

User reports for this quake

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
There are no user reports for this quake yet. If you felt it be the first to report it!
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Earlier earthquakes in the same area

Mag. 4.9 earthquake - Tonga (Samoa) on Friday, 21 July 1978 at 07:22 (GMT)
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