All earthquakes
1.1
very light
EARTHQUAKE DETAILS

M1.1 earthquake · 1 km North of Marmora (CN)

7 years ago · 15 Aug 2019, 07:54

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

1 km North of MarmoraEarthquakes 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

35 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 ≈ 25 s

Animation sped up ~5× compared to reality.

  • Cuneo
    35 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Moncalieri
    76 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Sanremo
    85 km from the epicentre
    first tremor in ~14 s
    main shaking in ~25 s
  • Torino
    87 km from the epicentre
    first tremor in ~15 s
    main shaking in ~25 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 (M2.4, 7 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.4
The mainshock
3 km North-West of Argentera
7 years ago · 21 Jul 2019, 17:40
Activity in the area right now (30 km radius)
0
last 24 hours
9
last 7 days
32
last 30 days
28 before6 after
this quake
Strongest of the sequence2.4

How often does it happen here?

about every ~15 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 283 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 · 48 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 · 29 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18085.3
Val Pellice earthquake
16 April 1808 · 48 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 11 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

0.9
7 years ago
15 Aug 2019, 07:49
0.5
7 years ago
15 Aug 2019, 01:19
1.5
1 km East of Pradleves
14 km East · 12 km
7 years ago
16 Aug 2019, 15:44
1.1
5 km North-West of Bellino
24 km North-West · 10 km
7 years ago
13 Aug 2019, 23:13
1.3
3 km North-West of Paesana
29 km North · 11 km
7 years ago
12 Aug 2019, 00:52
1.0
3 km North-West of Sampeyre
18 km North · 10 km
7 years ago
11 Aug 2019, 00:45
0.9
7 years ago
9 Aug 2019, 02:02
1.7
14 km West of Argentera
26 km West · 12 km
7 years ago
9 Aug 2019, 01:15
1.6
5 km South of Vinadio
24 km South · 7 km
7 years ago
21 Aug 2019, 23:51
0.8
2 km North-West of Sanfront
28 km North-East · 10 km
7 years ago
22 Aug 2019, 05:20

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).