All earthquakes
1.4
very light
EARTHQUAKE DETAILS

M1.4 earthquake · 5 km East of Tarvisio (UD)

3 years ago · 4 Mar 2023, 14:30

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 63% of Italian events in the past year

Where

5 km East of TarvisioEarthquakes 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

3 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.9kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×251 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 ≈ 40 s

Animation sped up ~8× compared to reality.

  • Udine
    55 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Trieste
    94 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 s
  • Pordenone
    97 km from the epicentre
    first tremor in ~16 s
    main shaking in ~28 s
  • Treviso
    141 km from the epicentre
    first tremor in ~24 s
    main shaking in ~40 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 (~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?

Aftershock

It is an aftershock: it follows a stronger quake (M2.1, 3 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.1
The mainshock
14 km North-East of Drenchia
3 years ago · 16 Feb 2023, 16:44
Activity in the area right now (30 km radius)
0
last 24 hours
1
last 7 days
5
last 30 days
1 before1 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~28 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 156 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 · 6 km from here
IX-XCompletely destructive: most buildings are destroyed.
19766.5
Friuli earthquake
6 May 1976 · 48 km from here
IX-XCompletely destructive: most buildings are destroyed.
15116.3
Friuli-Slovenia earthquake
26 March 1511 · 44 km from here
IXDestructive: many buildings partly or fully collapse.
16906.2
Carinthia, Villach earthquake
4 December 1690 · 25 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

Tarvisio

The epicentre lies about 3 km from Tarvisio, one of the seismic structures mapped by INGV geologists.

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

2.1
14 km North-East of Drenchia
23 km South · 9 km
3 years ago
16 Feb 2023, 16:44
0.6
2 km South-East of Resia
26 km South-West · 5 km
3 years ago
2 Apr 2023, 07:24

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).