All earthquakes
1.9
very light
EARTHQUAKE DETAILS

2 km North-West of Aprigliano

59 months ago · 25 Oct, 13:58

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 85% of Italian events in the past year

Where

2 km North-West of ApriglianoEarthquakes in the province of CosenzaEarthquakes 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

57 events
Magnitude:lightweakmoderatestrong

The energy released

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

11kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×45 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 ≈ 13 s

Animation sped up ~2× compared to reality.

  • Cosenza
    16 km from the epicentre
    first tremor in ~3 s
    main shaking in ~5 s
  • Lamezia Terme
    33 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Catanzaro
    40 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Corigliano-Rossano
    44 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 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

8 km
shallow

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?

Foreshock

In hindsight it was a foreshock: 58 months ago the same area had a stronger quake (M3.7). This can only be said after the fact — it was not predictable beforehand.

3.7
The mainshock
2 km South-East of Colosimi
58 months ago · 19 Nov, 19:54
Activity in the area right now (30 km radius)
1
last 24 hours
3
last 7 days
23
last 30 days
23 before33 after
this quake
Strongest of the sequence3.7

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: 664 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 · 49 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16386.8
Crotonese earthquake
8 June 1638 · 31 km from here
XCompletely destructive: most buildings are destroyed.
11846.8
Valle del Crati earthquake
24 May 1184 · 29 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

Savuto Valley

The epicentre lies about 2 km from Savuto Valley, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.1between 2 and 14 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

1.0
59 months ago
26 Oct, 08:55
1.0
6 km South-West of Acri
26 km North · 15 km
59 months ago
22 Oct, 23:21
1.9
5 km South of Cotronei
24 km East · 7 km
59 months ago
28 Oct, 08:49
1.6
59 months ago
28 Oct, 08:52
0.7
5 km South of Cotronei
24 km East · 7 km
59 months ago
28 Oct, 10:21
2.4
59 months ago
28 Oct, 14:08
1.7
59 months ago
29 Oct, 07:37
0.9
6 km South-West of Cotronei
20 km East · 10 km
59 months ago
29 Oct, 08:10
1.1
4 km South of Acri
26 km North · 24 km
59 months ago
20 Oct, 23:06
1.0
5 km South-West of Acri
27 km North · 10 km
59 months ago
20 Oct, 20:48

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).

We use cookies to analyse site traffic and improve your experience.

Privacy PolicyCookie Policy