Strong mag. 6.1 earthquake - 29 km southwest of ollong-gapo, Province of Zambales, Central Luzon, Philippines, on Sunday, August 23, 1998 at 05:36 GMT
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Strong magnitude 6.1 earthquake at 70 km depth
1 Jan 00:00 UTC: First to report: USGS after 30 seconds.
Magnitude: 6.1
Depth: 70.1 km
Epicenter latitude / longitude: 14.697°N / 120.046°E

Antipode: 14.697°S / 59.954°W
Nearest volcano: Natib (38 km / 24 mi)
Nearby towns and cities:
24 km (15 mi) W of Morong (Bataan) (pop: 16,100) --> See nearby quakes!
28 km (17 mi) S of San Antonio (Zambales) (pop: 34,200) --> See nearby quakes!
28 km (18 mi) SW of Subic (pop: 67,700) --> See nearby quakes!
29 km (18 mi) WSW of ollong-gapo (pop: 221,200) --> See nearby quakes!
31 km (19 mi) SSW of Castillejos (Zambales) (pop: 27,300) --> See nearby quakes!
33 km (21 mi) SSW of San Marcelino (Zambales) (pop: 18,700) --> See nearby quakes!
48 km (30 mi) WSW of Dinalupihan (pop: 66,700) --> See nearby quakes!
56 km (35 mi) WNW of Mariveles (pop: 84,600) --> See nearby quakes!
101 km (63 mi) W of Manila (pop: 1,600,000) --> See nearby quakes!
108 km (67 mi) W of Quezon City (pop: 2,761,700) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 8.9 x 1013 joules (24.8 gigawatt hours, equivalent to 21301 tons of TNT or 1.3 atomic bombs!) | about seismic energy
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.
Mag. | Depth | Location | Source |
6.1 | 70 km | Luzon, Philippines | USGS |
User reports for this quake
User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
Aftershocks
[More info]
Recorded aftershocks, latest first (3 quakes)
Date and time![]() | Mag Depth | Location | Details |
Dec 25, 1998 03:12 23 years ago | 4.2 140 km | 1.9 km NE of ollong-gapo, Province of Zambales, Central Luzon, Philippines | More |
Oct 21, 1998 03:18 24 years ago | 4.9 76 km | 45 km SW of ollong-gapo, Province of Zambales, Central Luzon, Philippines | More |
Aug 31, 1998 19:16 24 years ago | 5.4 68 km | 8.2 km NW of Subic, Province of Zambales, Central Luzon, Philippines | More |
Earlier earthquakes in the same area
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