All earthquakes
1.1
very light
EARTHQUAKE DETAILS

5 km East of Grugliasco

19 months ago · 28 Jan, 08:34

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 39% of Italian events in the past year

Where

5 km East of GrugliascoEarthquakes in the province of TorinoEarthquakes 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

5 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.7kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×708 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 ≈ 20 s

Animation sped up ~4× compared to reality.

  • Torino
    7 km from the epicentre
    first tremor in ~2 s
    main shaking in ~3 s
  • Moncalieri
    9 km from the epicentre
    first tremor in ~2 s
    main shaking in ~4 s
  • Asti
    46 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 s
  • Cuneo
    71 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 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

8 km
shallow

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

shallower than the area average (~16 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 (M1.5, 20 months ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

1.5
The mainshock
4 km South of Traves
20 months ago · 10 Jan, 10:10
Activity in the area right now (30 km radius)
0
last 24 hours
3
last 7 days
4
last 30 days
3 before1 after
this quake
Strongest of the sequence1.5

How often does it happen here?

about every ~2 months

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 68 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 · 39 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18085.3
Val Pellice earthquake
16 April 1808 · 35 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
19145.2
Torinese earthquake
26 October 1914 · 23 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
18865.2
Torinese earthquake
5 September 1886 · 27 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

Western Piemonte

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

estimated maximum magnitude 7.1between 1 and 8 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

0.8
2 km South-West of Traves
30 km North-West · 11 km
19 months ago
22 Jan, 12:24
0.9
2 km South of Germagnano
27 km North-West · 15 km
19 months ago
22 Jan, 11:28
1.5
4 km South of Traves
27 km North-West · 16 km
20 months ago
10 Jan, 10:10
1.4
3 km East of Giaveno
25 km West · 17 km
18 months ago
21 Feb, 08:40

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).

We use cookies to analyse site traffic and improve your experience.

Privacy PolicyCookie Policy