All earthquakes
1.2
very light
EARTHQUAKE DETAILS

3 km North of Sestola

123 months ago · 30 Apr, 18:10

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 47% of Italian events in the past year

Where

3 km North of SestolaEarthquakes in the province of ModenaEarthquakes in Emilia-Romagna

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

20 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 ≈ 14 s

Animation sped up ~3× compared to reality.

  • Pistoia
    32 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Reggio nell'Emilia
    49 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Modena
    49 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Bologna
    50 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 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 (~14 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?

Foreshock

In hindsight it was a foreshock: 123 months ago the same area had a stronger quake (M3.1). This can only be said after the fact — it was not predictable beforehand.

3.1
The mainshock
4 km North-West of Pavullo nel Frignano
123 months ago · 4 May, 10:17
Activity in the area right now (30 km radius)
0
last 24 hours
3
last 7 days
10
last 30 days
7 before12 after
this quake
Strongest of the sequence3.1

How often does it happen here?

about every ~5 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 814 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.

19206.5
Garfagnana earthquake
7 September 1920 · 42 km from here
XCompletely destructive: most buildings are destroyed.
15016.0
Modenese earthquake
5 June 1501 · 28 km from here
IXDestructive: many buildings partly or fully collapse.
18375.9
Lunigiana earthquake
11 April 1837 · 49 km from here
XCompletely destructive: most buildings are destroyed.
17405.6
Garfagnana earthquake
6 March 1740 · 32 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.

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

The closest seismic structure

Langhirano-Sassuolo

The epicentre lies about 18 km from Langhirano-Sassuolo, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.8between 2 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

1.7
3 km North-West of Bagni di Lucca
28 km South-West · 11 km
123 months ago
30 Apr, 23:00
1.3
2 km South-East of Camugnano
29 km South-East · 10 km
123 months ago
29 Apr, 23:56
3.1
123 months ago
4 May, 10:17
1.9
123 months ago
5 May, 21:58
2.4
4 km South-East of Serramazzoni
15 km North-East · 28 km
123 months ago
25 Apr, 02:36
1.7
2 km East of Montefiorino
15 km West · 9 km
123 months ago
7 May, 19:33
1.9
4 km North-East of Montese
14 km East · 24 km
123 months ago
15 May, 12:07
1.7
1 km South-East of Sambuca Pistoiese
29 km South-East · 51 km
123 months ago
15 May, 14:46
2.2
3 km South of Serramazzoni
15 km North · 28 km
124 months ago
15 Apr, 05:52
1.4
2 km South-East of Castel di Casio
26 km South-East · 11 km
123 months ago
16 May, 08:32

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