All earthquakes
0.9
very light
EARTHQUAKE DETAILS

M0.9 earthquake · 0 km West of Venzone (UD)

7 years ago · 4 Dec 2018, 10:52

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 23% of Italian events in the past year

Where

0 km West of VenzoneEarthquakes 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

23 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.3kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×1,413 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 ≈ 30 s

Animation sped up ~6× compared to reality.

  • Udine
    33 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Pordenone
    60 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 s
  • Trieste
    92 km from the epicentre
    first tremor in ~15 s
    main shaking in ~26 s
  • Treviso
    105 km from the epicentre
    first tremor in ~18 s
    main shaking in ~30 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

9 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?

Aftershock

It is an aftershock: it follows a stronger quake (M3.0, 7 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

3.0
The mainshock
4 km West of Lusevera
7 years ago · 10 Nov 2018, 08:59
Activity in the area right now (30 km radius)
1
last 24 hours
3
last 7 days
15
last 30 days
15 before7 after
this quake
Strongest of the sequence3.0

How often does it happen here?

about every ~16 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 262 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 · 36 km from here
IX-XCompletely destructive: most buildings are destroyed.
19766.5
Friuli earthquake
6 May 1976 · 12 km from here
IX-XCompletely destructive: most buildings are destroyed.
15116.3
Friuli-Slovenia earthquake
26 March 1511 · 16 km from here
IXDestructive: many buildings partly or fully collapse.
19286.0
Carnia earthquake
27 March 1928 · 15 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 1 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

0.6
7 years ago
3 Dec 2018, 05:11
1.1
1 km East of Amaro
6 km North-West · 9 km
7 years ago
1 Dec 2018, 17:55
0.6
7 years ago
7 Dec 2018, 13:26
0.8
7 years ago
1 Dec 2018, 01:14
0.6
4 km East of Villa Santina
15 km West · 11 km
7 years ago
29 Nov 2018, 23:55
1.1
1 km South of Lusevera
11 km South-East · 10 km
7 years ago
11 Dec 2018, 17:03
0.8
4 km South-East of Preone
20 km West · 6 km
7 years ago
26 Nov 2018, 05:28
0.6
7 years ago
25 Nov 2018, 12:09
1.3
3 km North of Trasaghis
11 km West · 15 km
7 years ago
15 Dec 2018, 01:38
1.4
6 km North of Moggio Udinese
20 km North · 8 km
7 years ago
16 Dec 2018, 13:32

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).