Seismic Event Dossier•03:18 Local (21:18 UTC)(95y ago)

M 7.9 earthquake
Xinjiang Uygur, China

A magnitude 7.9 (MW) earthquake occurred on 1931-08-10, 03:18 local time (21:18 UTC) (95y ago), centered 36 km SE of Koktokay (China). The hypocenter was located at a shallow depth of 10 km. Primary telemetry verified by USGS.

Historical Landmark Earthquake

#30 of All Time

Curated Global Seismic Archive (1700–Present)

Top-100 Earthquakes

A magnitude 7.9 earthquake struck ⁨Xinjiang Uygur, China⁩ on 10 agosto 1931. Source: ⁨Fuyun Fault, Central Segment⁩. Documented deaths: 10,000.

Documented Fatalities10,000Source: NOAA NCEI Significant Earthquake Database

Fault KinematicsActive Fault

Equivalent Energy10.68 Mt TNT

Magnitudo

M 7.9

10.68 Mt TNT

Profondità

10 km

shallow (Crostale superficiale)

Impatto PAGER

red

> 1,000 fatalities

Feriti: > 5,000 · ~42.3M avvertito

Mappa interattiva di epicentro e faglie

46.86°N, 89.89°E

Faglia5 km

Fuyun Fault, Central Segment

Active Fault · ~15.0 mm/yr

Felt byMMI III+

~42.3M exposed

~14.3M strong shaking

Primary SolutionUSGS

USGS#iscgem906933reviewed

1 agencies reporting

Setting46.9°N

China

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 (superficiale)35–70 km (intermedia)>70 km (profonda)Scossa principale

Previsione di rischio ML:12h36%24h48%72h62%7d77%

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	M7.9(Mw)Ref	10.0 kmRef	46.86°, 89.89°Origin	Authoritative	iscgem906933

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

4 centri abitati

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

Town	Distance	Intensity	Popolazione
Koktokay · Xinjiang Uygur	36 km	MMI IX	80,000
Altay · Xinjiang Uygur	174 km	MMI VII	142,000
Dund-Us · Hovd	184 km	MMI VII	30,500
Olgiy · Bayan-Ölgiy	231 km	MMI VII	34,934

Tectonic setting

Nearest mapped active fault: Fuyun Fault, Central Segment, 5 km away, slip rate ~15.0 mm/yr (GEM Global Active Faults).

M 7.9 earthquake Xinjiang Uygur, China