All earthquakes
0.7
very light
EARTHQUAKE DETAILS

M0.7 earthquake · 3 km West of Enemonzo (UD)

5 years ago · 1 May 2021, 17:32

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 11% of Italian events in the past year

Where

3 km West of EnemonzoEarthquakes in the province of UdineEarthquakes in Friuli-Venezia Giulia

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

14 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.2kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×2,818 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 ≈ 32 s

Animation sped up ~6× compared to reality.

  • Udine
    50 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Pordenone
    55 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Treviso
    95 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 s
  • Venezia
    112 km from the epicentre
    first tremor in ~19 s
    main shaking in ~32 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

5 km
shallow

At only a few km deep the shaking is felt more sharply at the surface.

in line with the area average (~9 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: 5 years ago the same area had a stronger quake (M1.4). This can only be said after the fact — it was not predictable beforehand.

1.4
The mainshock
2 km West of Gemona del Friuli
5 years ago · 4 May 2021, 01:29
Activity in the area right now (30 km radius)
1
last 24 hours
5
last 7 days
21
last 30 days
5 before8 after
this quake
Strongest of the sequence1.4

How often does it happen here?

about every ~18 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 236 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.

19766.5
Friuli earthquake
6 May 1976 · 29 km from here
IX-XCompletely destructive: most buildings are destroyed.
15116.3
Friuli-Slovenia earthquake
26 March 1511 · 37 km from here
IXDestructive: many buildings partly or fully collapse.
18736.3
Alpago Cansiglio earthquake
29 June 1873 · 45 km from here
IX-XCompletely destructive: most buildings are destroyed.
19286.0
Carnia earthquake
27 March 1928 · 11 km from here
IXDestructive: many buildings partly or fully collapse.

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

The closest seismic structure

Tramonti-Montemaggiore

The epicentre lies about 10 km from Tramonti-Montemaggiore, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.2between 1 and 6 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

1.4
5 years ago
4 May 2021, 01:29
0.7
4 km North of Tramonti di Sopra
13 km South-West · 9 km
5 years ago
4 May 2021, 21:30
0.4
2 km North-West of Preone
5 km South-East · 7 km
5 years ago
27 Apr 2021, 01:08
0.6
2 km East of Arta Terme
20 km East · 10 km
5 years ago
16 Apr 2021, 04:16
1.0
2 km South-East of Bordano
24 km East · 6 km
5 years ago
24 May 2021, 07:50
1.1
2 km South-East of Sauris
12 km West · 9 km
5 years ago
27 May 2021, 05:15
0.3
2 km South-West of Bordano
21 km East · 5 km
5 years ago
6 Apr 2021, 00:06
0.8
1 km South-East of Preone
8 km South-East · 10 km
5 years ago
4 Apr 2021, 16:38
1.3
3 km West of Venzone
24 km East · 11 km
5 years ago
30 May 2021, 02:38
0.6
6 km North-East of Paluzza
27 km North-East · 11 km
5 years ago
3 Apr 2021, 02:17

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).