All earthquakes
1.3
very light
EARTHQUAKE DETAILS

M1.3 earthquake · 5 km North-West of Lungro (CS)

9 years ago · 18 Apr 2017, 13:27

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 55% of Italian events in the past year

Where

5 km North-West of LungroEarthquakes 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

30 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.3kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×355 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 ≈ 28 s

Animation sped up ~5× compared to reality.

  • Corigliano-Rossano
    37 km from the epicentre
    first tremor in ~6 s
    main shaking in ~11 s
  • Cosenza
    60 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 s
  • Lamezia Terme
    95 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 s
  • Potenza
    99 km from the epicentre
    first tremor in ~17 s
    main shaking in ~28 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 (~22 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: 9 years ago the same area had a stronger quake (M2.5). This can only be said after the fact — it was not predictable beforehand.

2.5
The mainshock
3 km North-East of Laino Castello
9 years ago · 13 May 2017, 22:23
Activity in the area right now (30 km radius)
0
last 24 hours
1
last 7 days
12
last 30 days
8 before21 after
this quake
Strongest of the sequence2.5

How often does it happen here?

about every ~13 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 344 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.

11846.8
Valle del Crati earthquake
24 May 1184 · 46 km from here
IXDestructive: many buildings partly or fully collapse.
17675.9
Valle del Crati earthquake
14 July 1767 · 50 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
18365.9
Appennino lucano earthquake
20 November 1836 · 46 km from here
IXDestructive: many buildings partly or fully collapse.
19135.6
Calabria settentrionale earthquake
28 June 1913 · 33 km from here
VIII-IXDestructive: many buildings partly or fully collapse.

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

The closest seismic structure

Rimendiello-Mormanno

The epicentre lies about 7 km from Rimendiello-Mormanno, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.6between 1 and 12 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

1.5
6 km South-East of Laino Castello
13 km North-West · 8 km
9 years ago
16 Apr 2017, 04:34
1.5
5 km East of Mormanno
13 km North-West · 8 km
9 years ago
16 Apr 2017, 03:55
1.6
3 km East of Roggiano Gravina
20 km South-East · 9 km
9 years ago
20 Apr 2017, 23:53
1.2
7 km North of Castrovillari
15 km North-East · 10 km
9 years ago
23 Apr 2017, 02:36
1.5
5 km North-West of Castrovillari
14 km North-East · 10 km
9 years ago
23 Apr 2017, 13:44
1.7
4 km West of Aieta
27 km North-West · 26 km
9 years ago
12 Apr 2017, 01:14
1.0
3 km West of Maierà
21 km West · 24 km
9 years ago
12 Apr 2017, 00:29
1.4
6 km North of Castrovillari
15 km North-East · 10 km
9 years ago
11 Apr 2017, 18:32
1.0
6 km North of Castrovillari
15 km North-East · 10 km
9 years ago
10 Apr 2017, 23:24
1.5
9 years ago
27 Apr 2017, 09:29

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).