⊕earthquakeactive

M4.0 Earthquake — 161 km S of Nikolski, Alaska

M4.0

51.5152°N, 168.4220°W·US-AK

Started 2d ago

USGS data as of 03:50 UTC

Event Details

Typeearthquake

SeverityM4.0

Statusactive

Location51.5152°N, 168.4220°W (AK)

Started2026-10-19T05:08:40.403+00:00

Last Updated2026-10-20T05:05:38.824+00:00

Sourceusgs

Source URLearthquake.usgs.gov

Confidence1.00

Impact Zones — modeled

Catastrophic Impact Zone

Severe structural damage expected. Immediate danger to life.

1.0 km

Severe Impact Zone

Significant structural damage possible. Exercise extreme caution.

2.5 km

Moderate Impact Zone

Light to moderate damage. Check structures for damage.

5.0 km

Affected Zone

Shaking felt. Minor damage possible in vulnerable structures.

10.0 km

Zone estimates are based on scientific models and may differ from actual local conditions.

Impact Analysis

Population Exposed157

Structures in Zone60

Population from ACS 5-Year 2022 tract sampling; structure counts from Microsoft Building Footprints or Census ACS housing data, capped by USGS NLCD 2021 developed land. Estimates for situational awareness — not for actuarial, regulatory, or underwriting use.

Historical Comparison

1997 AK Earthquake46% match

M5 Earthquake in AK, 14km from current event

2013 AK Earthquake36% match

M5 Earthquake in AK, 73km from current event

2015 AK Earthquake34% match

M5 Earthquake in AK, 85km from current event

Historical comparison based on peril type, geography, and severity. Past events do not predict future outcomes.

View on Live Map

All US hazard profiles Scoring methodology

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Zone estimates are based on scientific models and may differ from actual local conditions.