All earthquakes
1.8
very light
EARTHQUAKE DETAILS

M1.8 earthquake · 24 km West of Leni (ME)

6 years ago · 26 Feb 2020, 07:58

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 82% of Italian events in the past year

Where

24 km West of LeniEarthquakes in the province of MessinaEarthquakes in Sicilia

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

33 events
Magnitude:lightweakmoderatestrong

The energy released

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

7.6kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×63 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 ≈ 31 s

Animation sped up ~6× compared to reality.

  • Messina
    89 km from the epicentre
    first tremor in ~15 s
    main shaking in ~26 s
  • Bagheria
    105 km from the epicentre
    first tremor in ~18 s
    main shaking in ~30 s
  • Acireale
    109 km from the epicentre
    first tremor in ~18 s
    main shaking in ~31 s
  • Reggio di Calabria
    109 km from the epicentre
    first tremor in ~18 s
    main shaking in ~31 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
shallow
1.1 times the height of Mount Everest

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

shallower than the area average (~37 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?

Foreshock

In hindsight it was a foreshock: 6 years ago the same area had a stronger quake (M3.1). This can only be said after the fact — it was not predictable beforehand.

3.1
The mainshock
23 km West of Leni
6 years ago · 29 Feb 2020, 10:18
Activity in the area right now (30 km radius)
0
last 24 hours
6
last 7 days
17
last 30 days
5 before27 after
this quake
Strongest of the sequence3.1

How often does it happen here?

about every ~5 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 919 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.

19786.0
Golfo di Patti earthquake
15 April 1978 · 47 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18235.8
Sicilia settentrionale earthquake
5 March 1823 · 39 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
19805.7
Tirreno meridionale earthquake
28 May 1980 · 26 km from here
VI-VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
16135.6
Monti Nebrodi earthquake
25 August 1613 · 46 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

Southern Tyrrhenian

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

estimated maximum magnitude 8.2between 2 and 18 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

1.6
25 km West of Leni
4 km South · 5 km
6 years ago
26 Feb 2020, 08:43
2.2
22 km West of Leni
3 km North-East · 14 km
6 years ago
26 Feb 2020, 07:11
2.2
Isole Eolie (Messina)
15 km North-West · 9 km
6 years ago
25 Feb 2020, 07:23
2.3
5 km South-West of Leni
19 km East · 19 km
6 years ago
24 Feb 2020, 06:04
2.9
23 km West of Leni
7 km North · 20 km
6 years ago
29 Feb 2020, 09:30
1.9
22 km West of Leni
4 km North · 14 km
6 years ago
29 Feb 2020, 09:48
2.3
22 km West of Leni
4 km North · 15 km
6 years ago
29 Feb 2020, 10:00
1.9
22 km West of Leni
4 km North · 15 km
6 years ago
29 Feb 2020, 10:08
3.1
23 km West of Leni
8 km North · 20 km
6 years ago
29 Feb 2020, 10:18
2.0
22 km West of Leni
1 km East · 10 km
6 years ago
29 Feb 2020, 10:20

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).