All earthquakes
1.0
very light
EARTHQUAKE DETAILS

M1.0 earthquake · 4 km South-East of Frassinoro (MO)

8 years ago · 25 Jul 2018, 00:13

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

Stronger than 31% of Italian events in the past year

Where

4 km South-East of FrassinoroEarthquakes 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

61 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.5kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×1,000 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 ≈ 13 s

Animation sped up ~2× compared to reality.

  • Massa
    35 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Pistoia
    37 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Carrara
    38 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Lucca
    40 km from the epicentre
    first tremor in ~7 s
    main shaking in ~13 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

18 km
medium depth
2 times the height of Mount Everest

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

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?

Aftershock

It is an aftershock: it follows a stronger quake (M3.6, 8 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

3.6
The mainshock
3 km West of Pievepelago
8 years ago · 1 Jul 2018, 09:32
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
6
last 30 days
167 before18 after
this quake
Strongest of the sequence3.6

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: 870 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 · 22 km from here
XCompletely destructive: most buildings are destroyed.
15016.0
Modenese earthquake
5 June 1501 · 42 km from here
IXDestructive: many buildings partly or fully collapse.
18375.9
Lunigiana earthquake
11 April 1837 · 30 km from here
XCompletely destructive: most buildings are destroyed.
17405.6
Garfagnana earthquake
6 March 1740 · 16 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

Garfagnana

The epicentre lies about 7 km from Garfagnana, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.9between 1 and 10 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

1.6
4 km North-West of Pievepelago
0 km South-East · 15 km
8 years ago
24 Jul 2018, 23:42
1.6
4 km North-West of Pievepelago
1 km South-East · 15 km
8 years ago
24 Jul 2018, 23:32
1.4
4 km East of Frassinoro
0 km North-East · 15 km
8 years ago
24 Jul 2018, 23:31
1.3
8 years ago
24 Jul 2018, 23:06
1.2
4 km North-West of Pievepelago
1 km South-East · 15 km
8 years ago
24 Jul 2018, 20:19
1.0
8 years ago
24 Jul 2018, 17:42
0.7
8 years ago
24 Jul 2018, 17:41
1.3
8 years ago
24 Jul 2018, 12:16
0.9
8 years ago
24 Jul 2018, 11:56
1.3
6 km North of Pievepelago
3 km North-East · 19 km
8 years ago
24 Jul 2018, 09:59

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).