All earthquakes
1.8
very light
EARTHQUAKE DETAILS

M1.8 earthquake · 2 km North-West of Casabona (KR)

8 years ago · 5 Sept 2018, 06:32

A very light earthquake, probably not felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 82% of Italian events in the past year

Where

2 km North-West of CasabonaEarthquakes 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

17 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 ≈ 18 s

Animation sped up ~3× compared to reality.

  • Crotone
    21 km from the epicentre
    first tremor in ~5 s
    main shaking in ~8 s
  • Catanzaro
    51 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Cosenza
    58 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 s
  • Corigliano-Rossano
    59 km from the epicentre
    first tremor in ~10 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

17 km
medium depth
2 times the height of Mount Everest

At this depth the shaking is felt, but rarely causes damage.

in line with the area average (~19 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 (M1.9, 8 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

1.9
The mainshock
7 km South-East of San Mauro Marchesato
8 years ago · 23 Aug 2018, 10:25
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
3
last 30 days
9 before7 after
this quake
Strongest of the sequence1.9

How often does it happen here?

about every ~7 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 617 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.

16386.8
Crotonese earthquake
8 June 1638 · 12 km from here
XCompletely destructive: most buildings are destroyed.
18326.7
Crotonese earthquake
8 March 1832 · 20 km from here
XCompletely destructive: most buildings are destroyed.
18366.2
Calabria settentrionale earthquake
25 April 1836 · 39 km from here
XCompletely destructive: most buildings are destroyed.
17445.7
Sila Piccola earthquake
21 March 1744 · 28 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

Crotone-Rossano

The epicentre lies about 14 km from Crotone-Rossano, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.3between 3 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

0.8
4 km South-West of Melissa
7 km East · 26 km
8 years ago
5 Sept 2018, 05:21
1.1
3 km North of Strongoli
10 km East · 27 km
8 years ago
5 Sept 2018, 05:00
0.8
1 km East of Casabona
3 km South-East · 24 km
8 years ago
5 Sept 2018, 04:08
0.8
2 km East of Strongoli
13 km East · 27 km
8 years ago
5 Sept 2018, 04:07
0.7
4 km East of Casabona
5 km East · 24 km
8 years ago
5 Sept 2018, 10:03
1.0
5 km West of Strongoli
6 km East · 25 km
8 years ago
11 Sept 2018, 08:20
1.4
8 years ago
28 Aug 2018, 10:53
1.5
8 years ago
28 Aug 2018, 10:05
1.9
8 years ago
23 Aug 2018, 10:25
1.0
15 km East of Cirò Marina
29 km East · 11 km
8 years ago
21 Aug 2018, 03:47

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).