All earthquakes
1.3
very light
EARTHQUAKE DETAILS

M1.3 earthquake · 7 km West of Pontebba (UD)

2 years ago · 20 Apr 2024, 12:17

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 55% of Italian events in the past year

Where

7 km West of PontebbaEarthquakes 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

22 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.3kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×355 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 ≈ 35 s

Animation sped up ~7× compared to reality.

  • Udine
    52 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Pordenone
    79 km from the epicentre
    first tremor in ~13 s
    main shaking in ~23 s
  • Trieste
    108 km from the epicentre
    first tremor in ~18 s
    main shaking in ~31 s
  • Treviso
    123 km from the epicentre
    first tremor in ~21 s
    main shaking in ~35 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

8 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: 2 years ago the same area had a stronger quake (M1.8). This can only be said after the fact — it was not predictable beforehand.

1.8
The mainshock
3 km North-East of Cavazzo Carnico
2 years ago · 19 May 2024, 07:10
Activity in the area right now (30 km radius)
3
last 24 hours
5
last 7 days
15
last 30 days
13 before8 after
this quake
Strongest of the sequence1.8

How often does it happen here?

about every ~20 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 220 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.

13486.6
Alpi Giulie earthquake
25 January 1348 · 27 km from here
IX-XCompletely destructive: most buildings are destroyed.
19766.5
Friuli earthquake
6 May 1976 · 33 km from here
IX-XCompletely destructive: most buildings are destroyed.
15116.3
Friuli-Slovenia earthquake
26 March 1511 · 36 km from here
IXDestructive: many buildings partly or fully collapse.
19286.0
Carnia earthquake
27 March 1928 · 26 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

Tarvisio

The epicentre sits above this source area: the deep structure where this area's earthquakes can originate.

estimated maximum magnitude 7.0between 1 and 14 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

1.1
7 km West of Pontebba
1 km North-West · 8 km
2 years ago
20 Apr 2024, 12:42
0.8
1 km West of Amaro
19 km South-West · 11 km
2 years ago
21 Apr 2024, 04:38
0.9
4 km East of Villa Santina
24 km South-West · 4 km
2 years ago
23 Apr 2024, 20:34
1.2
3 km West of Lauco
27 km West · 9 km
2 years ago
16 Apr 2024, 23:02
1.3
1 km East of Trasaghis
30 km South-West · 9 km
2 years ago
16 Apr 2024, 15:48
0.4
3 km West of Verzegnis
29 km South-West · 11 km
2 years ago
24 Apr 2024, 17:35
0.6
0 km North-East of Venzone
20 km South · 10 km
2 years ago
27 Apr 2024, 05:54
0.6
3 km West of Montenars
30 km South · 9 km
2 years ago
13 Apr 2024, 13:24
1.0
2 km North-East of Villa Santina
24 km South-West · 15 km
2 years ago
13 Apr 2024, 12:49
1.4
2 km North of Verzegnis
27 km South-West · 10 km
2 years ago
13 Apr 2024, 10:55

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).