All earthquakes
2.2
light
EARTHQUAKE DETAILS

M2.2 earthquake · 4 km East of Linguaglossa (CT)

6 years ago · 21 Dec 2019, 13:24

A light earthquake, rarely felt by people. At only a few km deep the shaking is felt more sharply at the surface.

Stronger than 92% of Italian events in the past year

Where

4 km East of LinguaglossaEarthquakes in the province of CataniaEarthquakes in Sicilia

Volcanic area: Mount Etna

Here the ground shakes mostly because of moving magma and underground fluids, not colliding plates: events are typically shallow, frequent and organised in swarms. This activity is constantly monitored by INGV.

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

52 events
Magnitude:lightweakmoderatestrong

The energy released

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

30kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×16 its energy
M1this quakeM3

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 ≈ 17 s

Animation sped up ~3× compared to reality.

  • Acireale
    22 km from the epicentre
    first tremor in ~4 s
    main shaking in ~6 s
  • Catania
    41 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Messina
    52 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Reggio di Calabria
    59 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 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

2 km
shallow

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

shallower than the area average (~13 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?

Seismic swarm

It is part of a seismic swarm: many closely spaced quakes in the same area, with no dominant shock. A typical, well-known behaviour of some Italian areas.

3.5
The mainshock
5 km North-East of Maletto
6 years ago · 18 Dec 2019, 00:48
Activity in the area right now (30 km radius)
0
last 24 hours
19
last 7 days
35
last 30 days
25 before26 after
this quake
Strongest of the sequence3.5

How often does it happen here?

about every ~2 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 2731 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.

18186.3
Catanese earthquake
20 February 1818 · 25 km from here
IX-XCompletely destructive: most buildings are destroyed.
17866.1
Golfo di Patti earthquake
10 March 1786 · 32 km from here
IXDestructive: many buildings partly or fully collapse.
16135.6
Monti Nebrodi earthquake
25 August 1613 · 45 km from here
IXDestructive: many buildings partly or fully collapse.
17805.5
Sicilia nord-orientale earthquake
28 March 1780 · 16 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.

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

The closest seismic structure

Patti-Giardini

The epicentre lies about 12 km from Patti-Giardini, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.1between 3 and 20 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

2.5
6 years ago
21 Dec 2019, 13:03
1.4
7 km North-East of Adrano
23 km West · 6 km
6 years ago
21 Dec 2019, 15:27
1.5
9 km East of Maletto
13 km West · 28 km
6 years ago
20 Dec 2019, 10:15
3.5
5 km North-East of Maletto
18 km West · 28 km
6 years ago
18 Dec 2019, 00:48
2.4
2 km West of Giarre
13 km South · 9 km
6 years ago
17 Dec 2019, 07:54
2.2
3 km North of Santa Venerina
14 km South · 7 km
6 years ago
17 Dec 2019, 07:46
1.4
8 km West of Sant'Alfio
17 km South-West · 9 km
6 years ago
27 Dec 2019, 22:01
2.0
3 km North-East of Milo
9 km South · 13 km
6 years ago
15 Dec 2019, 02:57
1.3
3 km North-East of Montalbano Elicona
22 km North-West · 11 km
6 years ago
31 Dec 2019, 03:25
1.6
4 km South-West of Sant'Alfio
13 km South-West · 8 km
6 years ago
1 Jan 2020, 15:24

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).