All earthquakes
3.1
weak
EARTHQUAKE DETAILS

M3.1 earthquake · 14 km South-East of Tarvisio (UD)

4 years ago · 28 Mar 2022, 11:00

A weak earthquake, felt by some of the population. At only a few km deep the shaking is felt more sharply at the surface.

Stronger than 98% of Italian events in the past year

Where

14 km South-East of TarvisioEarthquakes in the province of UdineEarthquakes in Friuli-Venezia Giulia

How far away could it be felt?

An estimate of how far people may have felt this quake.

  • up to ~13 km · felt only by some, at rest

The coloured rings on the map below show these distances.

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

4 events
Magnitude:lightweakmoderatestrong

The energy released

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

674kgof TNT equivalent
2.8 lightning bolts
M3
×1.4 the energy of a magnitude 3 earthquake
M2this quakeM4

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 ≈ 39 s

Animation sped up ~7× compared to reality.

  • Udine
    48 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Trieste
    82 km from the epicentre
    first tremor in ~14 s
    main shaking in ~24 s
  • Pordenone
    93 km from the epicentre
    first tremor in ~15 s
    main shaking in ~27 s
  • Treviso
    136 km from the epicentre
    first tremor in ~23 s
    main shaking in ~39 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

6 km
shallow

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

in line with the area average (~10 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?

Isolated quake

In the 30 days around this event no other quakes were recorded within 30 km: a one-off episode, very common in Italy.

Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
4
last 30 days
2 before1 after
this quake
Strongest of the sequence2.0

How often does it happen here?

about every ~5 months

Within 50 km of this epicentre, a magnitude ≥ 3 earthquake has occurred on average this often: 26 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 · 17 km from here
IX-XCompletely destructive: most buildings are destroyed.
19766.5
Friuli earthquake
6 May 1976 · 45 km from here
IX-XCompletely destructive: most buildings are destroyed.
15116.3
Friuli-Slovenia earthquake
26 March 1511 · 40 km from here
IXDestructive: many buildings partly or fully collapse.
16906.2
Carinthia, Villach earthquake
4 December 1690 · 33 km from here
VIII-IXDestructive: many buildings partly or fully collapse.

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

The closest seismic structure

Bovec-Tolminka Springs

The epicentre lies about 6 km from Bovec-Tolminka Springs, 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

0.9
3 km West of Taipana
30 km West · 8 km
4 years ago
17 Mar 2022, 23:14
2.0
5 km East of Drenchia
25 km South · 13 km
4 years ago
15 Mar 2022, 10:09
0.9
4 km East of Attimis
29 km South-West · 12 km
4 years ago
24 Apr 2022, 18:48

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).