Seismic Event Dossier•17:50 Local (22:50 UTC)(vừa xong)

M 8.1 earthquake
Nasca, Ica, Peru

A magnitude 8.1 (MW) earthquake occurred on 1942-08-24, 17:50 local time (22:50 UTC) (vừa xong), centered 25 km S of Nasca (Peru). The hypocenter was located at a shallow depth of 30 km. Primary telemetry verified by USGS.

Historical Landmark Earthquake

#90 of All Time

Curated Global Seismic Archive (1700–Present)

Top-100 Earthquakes

A magnitude 8.1 earthquake struck ⁨Nasca, Ica, Peru⁩ on 24 tháng 8, 1942. Source: ⁨Peru–Chile Trench⁩. Documented deaths: 30.

Documented Fatalities30Source: NOAA NCEI Significant Earthquake Database

Fault KinematicsSubduction Megathrust

Equivalent Energy21.30 Mt TNT

Độ lớn

M 8.1

21.30 Mt TNT

Độ sâu

30 km

shallow (Vỏ Trái Đất nông)

Tác động PAGER

red

> 1,000 fatalities

Người bị thương: > 5,000 · ~17.3M cảm nhận được

Bản đồ Tâm chấn & Đứt gãy Tương tác

15.04°S, 75.03°W

Đứt gãy5 km

Rãnh Peru–Chile

Subduction Megathrust · ~15.0 mm/yr

Felt byMMI III+

~17.3M exposed

~4.1M strong shaking

Primary SolutionUSGS

USGS#iscgem900444reviewed

1 agencies reporting

Setting15.0°S

Peru

Continental / Inland crustal

Seismic Activity & Aftershock Sequence

Timeline of foreshocks, main rupture, aftershocks and machine learning risk probability evolution.

Hover or tap a point to inspect aftershocks and risk probability curve.

<35 km (Nông)35–70 km (Trung bình)>70 km (Sâu)Chấn động chính

Dự báo Nguy cơ ML:12h37%24h49%72h64%7d80%

Situation Monitoring

Continuous verification

Multi-agency verification of casualties, tsunami alerts, and seismic sequence

Key facts so far

Casualties

Damage assessment in progress

Tsunami Status

No tsunami threat

NOAA PTWC & regional buoys

Citizen Felt Reports

No felt reports submitted

Macroseismic DYFI verification

Aftershock Sequence

Aftershocks: 1

High Omori aftershock probability

LightGBM hazard model forecast

Multi-agency seismic telemetry active. Awaiting wire headlines.

Agency Discrepancy Matrix (Cross-Network Verification)

Comparing multi-network solutions from primary and teleseismic monitoring agencies.

Network / Source	Magnitude (Scale & Diff)	Depth & Diff	Epicenter & Shift (Δd)	Consensus	Event ID / Data
USGS United States Geological Survey · Global / US	M8.1(Mw)Ref	30.0 kmRef	-15.04°, -75.03°Origin	Authoritative	iscgem900444

Why do agency magnitudes differ? Seismological agencies use different instrumentation networks, crustal velocity models, and mathematical magnitude scales (e.g. Moment Magnitude Mw vs Local Richter ML vs Surface Wave Ms). Differences of 0.1–0.3 are common and reflect physical observation geometry rather than errors.

Where it was felt

6 khu dân cư

Shaking intensity is modelled from magnitude, depth and distance (GMPE attenuation), not reported by residents.

Town	Distance	Intensity	Dân số
Nasca · Ica	25 km	MMI X	23,556
Ica · Ica	132 km	MMI VIII	279,420
Pisco · Ica	196 km	MMI VII	81,207
Chincha Alta · Ica	217 km	MMI VII	153,076
Ayacucho · Ayacucho	225 km	MMI VII	166,314
Huancavelica · Huancavelica	250 km	MMI VII	44,388

Tectonic setting

Nearest mapped active fault: Peru–Chile Trench, 5 km away, slip rate ~15.0 mm/yr (GEM Global Active Faults).

M 8.1 earthquake Nasca, Ica, Peru