Seismic Event Dossier•01:57 Local (23:57 UTC)(86y ago)

M 7.8 earthquake
Erzincan, Turkey

A magnitude 7.8 (MW) earthquake occurred on 1939-12-26, 01:57 local time (23:57 UTC) (86y ago), centered 19 km NE of Erzincan (Turkey). The hypocenter was located at a shallow depth of 20 km. Primary telemetry verified by USGS.

Historical Landmark Earthquake

#23 of All Time

Curated Global Seismic Archive (1700–Present)

Top-100 Earthquakes

A magnitude 7.8 earthquake struck ⁨Erzincan, Turkey⁩ on December 26, 1939. Source: ⁨North Anatolian Fault⁩. Documented deaths: 32,700.

Documented Fatalities32,700Source: NOAA NCEI Significant Earthquake Database

Fault KinematicsStrike-Slip

Equivalent Energy7.56 Mt TNT

Magnitude

M 7.8

7.56 Mt TNT

Depth

20 km

shallow (Shallow crustal)

PAGER Impact

red

> 1,000 fatalities

Injuries: > 5,000 · ~38.8M felt

Interactive Epicenter & Fault Map

39.91°N, 39.59°E

Fault5 km

North Anatolian Fault

Strike-Slip · ~15.0 mm/yr

Felt byMMI III+

~38.8M exposed

~11.9M strong shaking

Primary SolutionUSGS

USGS#iscgem902291reviewed

1 agencies reporting

Setting39.9°N

Turkey

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 (Shallow)35–70 km (Intermediate)>70 km (Deep)Mainshock

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

Monitoring

Aftershocks expected (Omori law)

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	M7.8(Mw)Ref	20.0 kmRef	39.91°, 39.59°Origin	Authoritative	iscgem902291

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 settlements

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

Town	Distance	Intensity	Population
Erzincan · Erzincan	19 km	MMI X	129,407
Gümüşhane · Gümüshane	63 km	MMI VIII	32,250
Tunceli · Tunceli	88 km	MMI VIII	29,062
Trabzon · Trabzon	120 km	MMI VII	764,714
Bingöl · Bingöl	138 km	MMI VII	80,568
Elâzığ · Elazig	140 km	MMI VII	271,492

Tectonic setting

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

M 7.8 earthquake Erzincan, Turkey