All earthquakes
1.0
very light
EARTHQUAKE DETAILS

M1.0 earthquake · 3 km North of Frisanco (PN)

4 years ago · 18 Sept 2022, 18:56

A very light earthquake, probably not felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 31% of Italian events in the past year

Where

3 km North of FrisancoEarthquakes in the province of PordenoneEarthquakes 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

32 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.5kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×1,000 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 ≈ 26 s

Animation sped up ~5× compared to reality.

  • Pordenone
    35 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Udine
    48 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Treviso
    74 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Venezia
    92 km from the epicentre
    first tremor in ~15 s
    main shaking in ~26 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

10 km
medium depth
1.1 times the height of Mount Everest

At this depth the shaking is felt, but rarely causes damage.

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 (M3.5, 4 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

3.5
The mainshock
3 km East of Frisanco
4 years ago · 25 Aug 2022, 02:34
Activity in the area right now (30 km radius)
1
last 24 hours
5
last 7 days
20
last 30 days
9 before22 after
this quake
Strongest of the sequence3.5

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: 243 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 · 33 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.
18736.3
Alpago Cansiglio earthquake
29 June 1873 · 26 km from here
IX-XCompletely destructive: most buildings are destroyed.
19366.1
Alpago Cansiglio earthquake
18 October 1936 · 30 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

Andreis-Forgaria nel Friuli

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

estimated maximum magnitude 6.7between 1 and 8 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

2.6
3 km North-West of Forni di Sotto
18 km North-West · 9 km
4 years ago
18 Sept 2022, 01:32
1.4
3 km North-East of Arba
12 km South-East · 12 km
4 years ago
17 Sept 2022, 15:52
1.1
2 km South of Socchieve
15 km North-East · 11 km
4 years ago
20 Sept 2022, 01:57
1.2
3 km South of Barcis
16 km South-West · 11 km
4 years ago
21 Sept 2022, 10:34
0.6
3 km North of Frisanco
1 km North-West · 9 km
4 years ago
22 Sept 2022, 02:27
1.2
4 km West of Chies d'Alpago
26 km West · 8 km
4 years ago
23 Sept 2022, 13:50
0.9
2 km East of Cavasso Nuovo
11 km South-East · 15 km
4 years ago
24 Sept 2022, 11:26
1.0
3 km North-West of Forni di Sotto
18 km North-West · 4 km
4 years ago
26 Sept 2022, 14:29
1.3
4 km North of Andreis
6 km West · 9 km
4 years ago
10 Sept 2022, 11:00
1.0
3 km North-East of Raveo
27 km North-East · 8 km
4 years ago
28 Sept 2022, 22:36

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).