Mag. 4.6 earthquake - Tonga on Saturday, 21 March 1987 at 16:33 (GMT)

Mag. 4.6 earthquake - Tonga on Saturday, 21 March 1987 at 16:33 (GMT)

Light magnitude 4.6 earthquake at 244 km depth

Date & time: 21 Mar 1987 16:33:40 UTC
Magnitude: 4.6
Depth: 244.1 km
Epicenter latitude / longitude: 19.644°S / 175.864°W (Tonga)
Nearest volcano: Tofua (84 km / 52 mi)
Nearby towns and cities:
159 km (99 mi) W of Pangai (pop: 1,740) --> See nearby quakes!
180 km (112 mi) NNW of Nuku'alofa (pop: 22,400) --> See nearby quakes!
180 km (112 mi) NNW of Nuku‘alofa (pop: 22,400) --> See nearby quakes!
185 km (115 mi) NNW of Kolonga (pop: 1,100) --> See nearby quakes!
211 km (131 mi) NNW of ‘Ohonua (Ohonua) (pop: 1,240) --> See nearby quakes!
226 km (141 mi) WSW of Neiafu (pop: 4,320) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 5 x 1011 joules (139 megawatt hours, equivalent to 120 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 4.6244 kmTongaUSGS
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. 4.6 earthquake - Tonga on Saturday, 21 March 1987 at 16:33 (GMT)
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