All earthquakes
0.9
very light
EARTHQUAKE DETAILS

M0.9 earthquake · 7 km West of Cotronei (KR)

6 years ago · 24 Feb 2020, 19:43

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

7 km West of CotroneiEarthquakes in the province of CrotoneEarthquakes in Calabria

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

61 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 ≈ 12 s

Animation sped up ~2× compared to reality.

  • Catanzaro
    31 km from the epicentre
    first tremor in ~5 s
    main shaking in ~9 s
  • Cosenza
    34 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Lamezia Terme
    38 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Crotone
    40 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 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
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 (~18 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 (M3.1, 6 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

3.1
The mainshock
3 km North of Albi
6 years ago · 2 Feb 2020, 20:24
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
7
last 30 days
75 before22 after
this quake
Strongest of the sequence3.1

How often does it happen here?

about every ~6 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 766 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.

16387.1
Calabria centrale earthquake
27 March 1638 · 33 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17837.0
Calabria centrale earthquake
28 March 1783 · 45 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16386.8
Crotonese earthquake
8 June 1638 · 19 km from here
XCompletely destructive: most buildings are destroyed.
11846.8
Valle del Crati earthquake
24 May 1184 · 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

Ampollino Lake

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

estimated maximum magnitude 7.1between 1 and 15 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

0.7
4 km South-East of Parenti
13 km West · 9 km
6 years ago
24 Feb 2020, 18:10
1.6
3 km South-East of Taverna
10 km South-West · 7 km
6 years ago
24 Feb 2020, 21:27
0.8
6 km West of Cotronei
2 km South-East · 11 km
6 years ago
23 Feb 2020, 16:31
0.8
3 km North of Albi
12 km South · 9 km
6 years ago
21 Feb 2020, 03:15
0.9
8 km West of Cotronei
1 km South-West · 10 km
6 years ago
29 Feb 2020, 06:25
2.0
4 km North of Albi
10 km South · 8 km
6 years ago
29 Feb 2020, 18:05
0.8
4 km North-East of Albi
10 km South · 8 km
6 years ago
29 Feb 2020, 18:08
1.2
3 km South-East of Taverna
9 km South-West · 5 km
6 years ago
29 Feb 2020, 23:19
0.7
4 km North-East of Albi
10 km South · 8 km
6 years ago
19 Feb 2020, 10:57
1.3
6 years ago
18 Feb 2020, 11:36

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).