Reviewed by USGSChile28y ago
M3.4 earthquake 53 km W of Illapel, Chile
Tuesday, July 7, 1998, 03:58:24 UTC · 31.638°S, 71.730°W
A magnitude 3.4 earthquake struck 53 km W of Illapel, Chile on Tuesday, July 7, 1998, 03:58:24 UTC, at a depth of 22.9 km (shallow).
- Magnitude
- 3.4
- Minor · md
- Depth
- 23 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
2 tons of TNT
That is about 1/7,931 of the Hiroshima bomb. A magnitude 5.0 releases about 251 times more energy.
Tectonic setting
91 km
from the nearest mapped plate boundary, between the Nazca and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
23 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 50 km
USGS lists 17 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.5 on July 28, 1998. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.470 km NW of Illapel, Chile28y ago · 42 km N of this epicenter
- 3.668 km WSW of Illapel, Chile28y ago · 26 km SW of this epicenter
- 4.255 km NW of Illapel, Chile28y ago · 45 km N of this epicenter
- 4.525 km SSW of Illapel, Chile28y ago · 48 km SE of this epicenter
- 3.554 km NW of Illapel, Chile28y ago · 46 km NE of this epicenter
- 4.463 km NW of La Ligua, Chile28y ago · 48 km S of this epicenter
- 3.980 km WNW of Illapel, Chile28y ago · 33 km NW of this epicenter
- 3.757 km NW of La Ligua, Chile28y ago · 45 km S of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 474 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2The 1906 Valparaiso, Chile EarthquakeAugust 17, 1906 · 90 km S of this epicenter
- 8.145 km NNW of Illapel, ChileApril 6, 1943 · 54 km NE of this epicenter
- 8.025 km WSW of Valparaíso, ChileMarch 3, 1985 · 167 km S of this epicenter
- 7.819 km NNE of Hacienda La Calera, ChileJuly 9, 1971 · 121 km SE of this epicenter
- 7.47 km SSE of La Ligua, ChileMarch 28, 1965 · 109 km SE of this epicenter
- 7.419 km S of Valparaíso, ChileMarch 4, 1985 · 175 km S of this epicenter
- 7.237 km S of San Antonio, ChileMarch 18, 1931 · 255 km S of this epicenter
- 7.259 km S of San Antonio, ChileApril 9, 1985 · 277 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 43 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 4,778 recorded deaths. The most severe:
- 1906M8.2
South Central
17 Aug 1906 · 154 km away · intensity XI
4,000 deaths$100 million damagetsunami
- 1965M7.3
Central
28 Mar 1965 · 98 km away
400 deaths$125 million damage
- 1985M8.0
Central Coast, San Antonio, Valparaiso
3 Mar 1985 · 166 km away · intensity VIII
180 deaths$1.5 billion damagetsunami
- 1971M7.8
Central
9 Jul 1971 · 108 km away · intensity IX
83 deaths$236 million damagetsunami
- 1822M8.5
Valparaiso, Quillota, Concon, Aconcagua
20 Nov 1822 · 154 km away · intensity XI
72 deathsExtreme damage ($25M+)tsunami
- 1943M8.2
Illapel
6 Apr 1943 · 102 km away
11 deathsLimited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.