All earthquakes
1.7
very light
EARTHQUAKE DETAILS

M1.7 earthquake outside Italy

9 years ago · 10 Nov 2016, 12:10

A very light earthquake, probably not felt by people. At this depth the shaking is felt, but rarely causes damage.

Where

Nearest Italian town: Claviere (TO)Earthquakes in the province of TorinoEarthquakes in Piemonte

Epicentre abroad

The epicentre lies outside Italy's borders. The quake appears here because the INGV seismic network also records events close to Italy, which can be felt on Italian territory.

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

19 events
Magnitude:lightweakmoderatestrong

The energy released

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

5.4kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×89 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 ≈ 36 s

Animation sped up ~7× compared to reality.

  • Cuneo
    83 km from the epicentre
    first tremor in ~14 s
    main shaking in ~24 s
  • Moncalieri
    88 km from the epicentre
    first tremor in ~15 s
    main shaking in ~25 s
  • Torino
    92 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 s
  • Asti
    126 km from the epicentre
    first tremor in ~21 s
    main shaking in ~36 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
medium depth
1.1 times the height of Mount Everest

At this depth the shaking is felt, but rarely causes damage.

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 (M2.0, 9 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.0
The mainshock
18 km South-West of Claviere
9 years ago · 10 Nov 2016, 09:56
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
4
last 30 days
6 before12 after
this quake
Strongest of the sequence2.0

How often does it happen here?

about every ~24 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 180 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 · 50 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19595.4
Ubaye earthquake
5 April 1959 · 30 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19355.3
Embrunais earthquake
19 March 1935 · 13 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18845.2
Alpi Cozie earthquake
27 November 1884 · 18 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

2.0
9 years ago
10 Nov 2016, 09:56
1.4
20 km South-West of Claviere
1 km North-West · 10 km
9 years ago
10 Nov 2016, 07:28
1.8
9 years ago
11 Nov 2016, 10:31
1.3
25 km West of Acceglio
27 km South · 11 km
9 years ago
13 Nov 2016, 00:36
1.8
24 km West of Acceglio
26 km South · 11 km
9 years ago
3 Nov 2016, 01:13
1.4
24 km West of Acceglio
26 km South · 9 km
9 years ago
19 Nov 2016, 22:46
1.4
11 km North-West of Claviere
26 km North · 11 km
9 years ago
26 Oct 2016, 06:36
1.9
12 km West of Bellino
24 km South-East · 6 km
9 years ago
22 Oct 2016, 23:28
1.5
9 years ago
30 Nov 2016, 00:47
1.4
Confine Italia-Francia (FRANCIA)
27 km South · 14 km
9 years ago
2 Dec 2016, 12:14

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).