Major magnitude. 7.7 earthquake - Mariana Islands Region (Northern Mariana Islands) on Saturday, 28 December 1940 at 16:37 (GMT)

Major magnitude. 7.7 earthquake  - Mariana Islands Region (Northern Mariana Islands) on Saturday, 28 December 1940 at 16:37 (GMT)

Major magnitude 7.7 earthquake at 15 km depth

Date & time: 28 Dec 1940 04:37:44 UTC###AGESTRINGCOPY###
Magnitude: 7.7
Depth: 15.0 km
Epicenter latitude / longitude: 18.245°N / 147.558°E (Northern Mariana Islands)
Nearest volcano: Pagan (186 km / 116 mi)
Nearby towns and cities:
191 km (118 mi) E of Pagan Village (Pagan Island) (pop: 50)
388 km (241 mi) NNE of Saipan (pop: 48,200)
419 km (260 mi) NNE of San Jose (pop: 15,000)
601 km (373 mi) NNE of Dededo Village (Guam) (pop: 44,900)
612 km (380 mi) NNE of Chalan Pago-Ordot Village (Guam) (pop: 6,820)
622 km (387 mi) NNE of Santa Rita Village (Guam) (pop: 7,500)
629 km (391 mi) NNE of Inarajan Village (Guam) (pop: 3,050)
Primary data source: USGS
Estimated released energy: 2.2 x 1016 joules (6219 gigawatt hours, equivalent to 5.4 x 106 tons of TNT or 334.4 atomic bombs!) 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.
M 7.715 kmMariana Islands region (Northern Mariana Islands)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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Aftershocks of the 7.7 quake Mariana Islands Region (Northern Mariana Islands) 28 December 16:37 UTC

More info
Recorded aftershocks, latest first (1 quakes):

Earlier earthquakes in the same area

Major magnitude. 7.7 earthquake - Mariana Islands Region (Northern Mariana Islands) on Saturday, 28 December 1940 at 16:37 (GMT)
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