All earthquakes
0.9
very light
EARTHQUAKE DETAILS

M0.9 earthquake · 10 km North-West of Acceglio (CN)

2 years ago · 24 Aug 2024, 08:38

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 23% of Italian events in the past year

Where

10 km North-West of AcceglioEarthquakes in the province of CuneoEarthquakes in Piemonte

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

56 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.3kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×1,413 its energy
M0this quakeM2

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 ≈ 31 s

Animation sped up ~6× compared to reality.

  • Cuneo
    56 km from the epicentre
    first tremor in ~10 s
    main shaking in ~16 s
  • Moncalieri
    83 km from the epicentre
    first tremor in ~14 s
    main shaking in ~24 s
  • Torino
    93 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 s
  • Sanremo
    106 km from the epicentre
    first tremor in ~18 s
    main shaking in ~31 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 (~11 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 (M2.8, 2 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.8
The mainshock
11 km North-West of Acceglio
2 years ago · 20 Aug 2024, 11:51
Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
9
last 30 days
37 before18 after
this quake
Strongest of the sequence2.8

How often does it happen here?

about every ~16 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 276 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.

18085.6
Val Pellice earthquake
2 April 1808 · 47 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19595.4
Ubaye earthquake
5 April 1959 · 7 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19355.3
Embrunais earthquake
19 March 1935 · 24 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18845.2
Alpi Cozie earthquake
27 November 1884 · 49 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.

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

The closest seismic structure

Brianconnais

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

estimated maximum magnitude 7.2between 5 and 20 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

1.5
10 km West of Bellino
2 km North-East · 8 km
2 years ago
26 Aug 2024, 04:18
0.9
7 km South-West of Bellino
5 km East · 11 km
2 years ago
26 Aug 2024, 16:14
1.1
Confine Italia-Francia (FRANCIA)
25 km West · 10 km
2 years ago
26 Aug 2024, 17:01
1.5
4 km South-East of Bellino
13 km East · 11 km
2 years ago
28 Aug 2024, 02:20
0.8
10 km West of Acceglio
0 km South-East · 9 km
2 years ago
20 Aug 2024, 12:45
2.6
2 years ago
20 Aug 2024, 12:39
2.4
12 km West of Acceglio
2 km West · 15 km
2 years ago
20 Aug 2024, 12:17
1.5
11 km West of Acceglio
1 km West · 19 km
2 years ago
20 Aug 2024, 12:15
2.1
2 years ago
20 Aug 2024, 12:10
2.7
11 km West of Acceglio
4 km South-West · 10 km
2 years ago
20 Aug 2024, 12:04

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).