M7.0 earthquake 95 km W of Pariaman, Indonesia

Wednesday, April 1, 1998, 17:56:23 UTC · 0.544°S, 99.261°E

A magnitude 7.0 earthquake struck 95 km W of Pariaman, Indonesia on Wednesday, April 1, 1998, 17:56:23 UTC, at a depth of 55.7 km (shallow). It is the strongest earthquake within 300 km since an M7.1 on November 17, 1984.

Magnitude: 7.0; Major · mwc
Depth: 56 km; Shallow
Felt reports: 0; Did You Feel It?
Est. shaking: VI; Strong (ShakeMap)
PAGER alert: None; Not issued
Tsunami: No flag; USGS feed

Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

477 kilotons of TNT

That is about 32 times the Hiroshima bomb. It released about 1,000 times the energy of a magnitude 5.0.

Tectonic setting

142 km

from the nearest mapped plate boundary, between the Nazca and North Andes plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

Depth: shallow

56 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 200 km

USGS lists 5 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M4.8 on April 20, 1998. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 205 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 21 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,439 recorded deaths. The most severe:

1861M8.5
Lagundi, Simuk, Tello I
16 Feb 1861 · 202 km away · intensity IX
1,105 deathsModerate damage ($1–5M)tsunami
1861M7.0
Sw. Sumatra
9 Mar 1861 · 153 km away
950 deathsSevere damage ($5–24M)tsunami
1797M8.0
Sw. Sumatra
10 Feb 1797 · 67 km away · intensity IX
300 deathsModerate damage ($1–5M)tsunami
1995M6.8
Sumatera, Jambi Province
6 Oct 1995 · 294 km away
84 deathsExtreme damage ($25M+)
1909M7.6
Sw Sumatra: Kerintji, Redjanglebong
3 Jun 1909 · 252 km away
Severe damage ($5–24M)tsunami
1843M7.3
Sw. Sumatra
5 Jan 1843 · 267 km away · intensity XI
Severe damage ($5–24M)tsunami

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers