All earthquakes
1.2
very light
EARTHQUAKE DETAILS

M1.2 earthquake · 3 km East of Pradleves (CN)

10 years ago · 11 Jul 2016, 17:40

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 48% of Italian events in the past year

Where

3 km East of PradlevesEarthquakes 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

27 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.0kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×501 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 ≈ 23 s

Animation sped up ~4× compared to reality.

  • Cuneo
    20 km from the epicentre
    first tremor in ~4 s
    main shaking in ~6 s
  • Moncalieri
    69 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 s
  • Sanremo
    76 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Torino
    81 km from the epicentre
    first tremor in ~14 s
    main shaking in ~23 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

9 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 (M2.1, 10 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.1
The mainshock
1 km East of Macra
10 years ago · 27 Jun 2016, 19:59
Activity in the area right now (30 km radius)
0
last 24 hours
7
last 7 days
27
last 30 days
16 before10 after
this quake
Strongest of the sequence2.1

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: 263 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.

15645.8
Lantosque earthquake
20 July 1564 · 45 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
18085.6
Val Pellice earthquake
2 April 1808 · 46 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19595.4
Ubaye earthquake
5 April 1959 · 44 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18085.3
Val Pellice earthquake
16 April 1808 · 47 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 lies about 26 km from Brianconnais, one of the seismic structures mapped by INGV geologists.

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

0.8
1 km North-East of Borgo San Dalmazzo
17 km South-East · 10 km
10 years ago
11 Jul 2016, 06:03
1.0
2 km South-West of Robilante
23 km South-East · 4 km
10 years ago
8 Jul 2016, 11:57
1.1
1 km North-West of Prazzo
23 km West · 10 km
10 years ago
15 Jul 2016, 13:18
1.4
2 km North of Roaschia
22 km South-East · 5 km
10 years ago
7 Jul 2016, 09:21
0.7
10 years ago
7 Jul 2016, 09:15
1.0
1 km South of Pradleves
3 km South-West · 11 km
10 years ago
7 Jul 2016, 00:36
0.8
4 km South-West of Valloriate
14 km South · 13 km
10 years ago
5 Jul 2016, 02:33
1.3
3 km South-West of Aisone
20 km South-West · 10 km
10 years ago
4 Jul 2016, 16:43
1.3
10 years ago
20 Jul 2016, 01:07
1.8
2 km East of Stroppo
15 km North-West · 9 km
10 years ago
3 Jul 2016, 03:26

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).