All earthquakes
1.5
very light
EARTHQUAKE DETAILS

M1.5 offshore earthquake

1 year ago · 8 Sept 2025, 07:07

A very light earthquake, probably not felt by people. At only a few km deep the shaking is felt more sharply at the surface.

Stronger than 69% of Italian events in the past year

Where

Nearest Italian town: Noli (SV)Earthquakes in the province of SavonaEarthquakes in Liguria

Epicentre at sea

The epicentre is at sea: for the same magnitude, the shaking is felt less on land, because the energy fades along the way before reaching the coast.

How far away could it be felt?

A quake this small is usually not felt by people: only seismographs record it.

Statistical estimate from the Italian intensity attenuation model (INGV): actual perception depends on geology, buildings and depth. Very shallow events can be felt locally even below the threshold.

Earthquake map

3 events
Magnitude:lightweakmoderatestrong

The energy released

How much energy this quake unleashed, translated into everyday comparisons.

2.7kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×178 its energy
M1this quakeM3

Each extra magnitude unit releases about 32 times more energy: an M5 is not "a bit stronger" than an M4 — it is a different league.

Energy estimated with the standard Gutenberg–Richter relation; an average lightning bolt ≈ 1 billion joules. Indicative values.

The race of the seismic waves

Two waves set off from the hypocentre: the faster P wave arrives first with a sharp jolt; the S wave carries the actual shaking.

P waves — the first sharp jolt (~6 km/s)S waves — the strongest shaking (~3.5 km/s)
t ≈ 29 s

Animation sped up ~5× compared to reality.

  • Savona
    43 km from the epicentre
    first tremor in ~7 s
    main shaking in ~13 s
  • Genova
    56 km from the epicentre
    first tremor in ~10 s
    main shaking in ~16 s
  • Sanremo
    68 km from the epicentre
    first tremor in ~11 s
    main shaking in ~20 s
  • Cuneo
    100 km from the epicentre
    first tremor in ~17 s
    main shaking in ~29 s

Theoretical times with average crustal speeds: real values vary with geology. The gap between P and S waves is what earthquake early-warning systems rely on.

How deep it was born

10 km
shallow
1.1 times the height of Mount Everest

At only a few km deep the shaking is felt more sharply at the surface.

in line with the area average (~8 km)

For the same magnitude, a shallow earthquake is felt much more than a deep one: the energy starts closer to the surface.

What kind of quake is this?

Aftershock

It is an aftershock: it follows a stronger quake (M1.6, 1 year ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

1.6
The mainshock
Costa Ligure centro-occidentale (Savona)
1 year ago · 15 Aug 2025, 19:20
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
0
last 30 days
1 before1 after
this quake
Strongest of the sequence1.6

How often does it happen here?

about every ~4 months

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 32 events in the last 12 years of the INGV catalogue.

An average computed on the recent past: it tells how used this area is to shaking, not when the next quake will come — earthquakes cannot be predicted.

The great earthquakes in this area's history

Almost a thousand years of catalogues: the strongest documented events within ~50 km.

18876.3
Liguria occidentale earthquake
23 February 1887 · 50 km from here
XCompletely destructive: most buildings are destroyed.
18185.3
Liguria occidentale earthquake
23 February 1818 · 46 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19684.9
Liguria occidentale earthquake
18 April 1968 · 47 km from here
18964.9
Liguria occidentale earthquake
16 October 1896 · 22 km from here
VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.

Source: Parametric Catalogue of Italian Earthquakes CPTI15 (INGV, CC BY 4.0).

The closest seismic structure

Imperia Promontory

The epicentre sits above this source area: the deep structure where this area's earthquakes can originate.

estimated maximum magnitude 7.4between 3 and 15 km deep

Faults are mapped to build better and understand the territory: knowing them says nothing about when an earthquake will occur, which remains unpredictable. Source: DISS 3.3 (INGV, CC BY 4.0).

Other quakes in the area

0.6
9 km East of Bergeggi
30 km North · 12 km
1 year ago
28 Sept 2025, 03:30
1.6
Costa Ligure centro-occidentale (Savona)
1 km South · 10 km
1 year ago
15 Aug 2025, 19:20

Data: INGV — National Institute of Geophysics and Volcanology (CC-BY 4.0)

Estimates computed by Meteare on INGV data (Gutenberg–Richter relation; Italian macroseismic intensity attenuation model).