All earthquakes
3.2
weak
EARTHQUAKE DETAILS

M3.2 earthquake · 3 km North-East of Cortale (CZ)

11 years ago · 6 Feb 2015, 20:09

A weak earthquake, felt by some of the population. At only a few km deep the shaking is felt more sharply at the surface.

No. 10 of the month in ItalyStronger than 98% of Italian events in the past year

Where

3 km North-East of CortaleEarthquakes in the province of CatanzaroEarthquakes in Calabria

How far away could it be felt?

An estimate of how far people may have felt this quake.

  • up to ~15 km · felt only by some, at rest
    ≈ 165,000 people live in this area

The coloured rings on the map below show these distances.

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

14 events
Magnitude:lightweakmoderatestrong

The energy released

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

952kgof TNT equivalent
4.0 lightning bolts
M3
×2 the energy of a magnitude 3 earthquake
M2this quakeM4

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 ≈ 18 s

Animation sped up ~3× compared to reality.

  • Catanzaro
    15 km from the epicentre
    first tremor in ~3 s
    main shaking in ~5 s
  • Lamezia Terme
    18 km from the epicentre
    first tremor in ~3 s
    main shaking in ~5 s
  • Cosenza
    49 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Crotone
    63 km from the epicentre
    first tremor in ~11 s
    main shaking in ~18 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

7 km
shallow

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

shallower than the area average (~15 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?

Mainshock

It is the strongest quake of its sequence: so far it has been followed by 9 aftershocks within 30 km. Aftershocks tend to fade in number and strength over time.

Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
27
last 30 days
4 before9 after
this quake
Strongest of the sequence3.0

How often does it happen here?

about every ~2 months

Within 50 km of this epicentre, a magnitude ≥ 3 earthquake has occurred on average this often: 63 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 · 25 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17837.0
Calabria centrale earthquake
28 March 1783 · 8 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
19057.0
Calabria centrale earthquake
8 September 1905 · 38 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17836.7
Calabria centrale earthquake
7 February 1783 · 37 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.

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

The closest seismic structure

Caraffa-Squillace Gulf

The epicentre lies about 1 km from Caraffa-Squillace Gulf, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.9between 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

3.0
11 years ago
6 Feb 2015, 20:13
1.5
6 km East of Colosimi
30 km North · 9 km
11 years ago
7 Feb 2015, 21:03
2.1
5 km North-East of Panettieri
29 km North · 10 km
11 years ago
7 Feb 2015, 22:35
1.8
2 km North-West of Lamezia Terme
19 km North-West · 9 km
11 years ago
8 Feb 2015, 06:42
1.9
11 years ago
10 Feb 2015, 18:12
1.3
6 km North-East of Panettieri
30 km North · 10 km
11 years ago
10 Feb 2015, 18:39
1.4
11 years ago
2 Feb 2015, 21:05
2.3
2 km East of Panettieri
25 km North · 9 km
11 years ago
2 Feb 2015, 06:52
2.2
11 years ago
16 Feb 2015, 10:51
1.1
11 years ago
2 Mar 2015, 19:44

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).