All earthquakes
0.9
very light
EARTHQUAKE DETAILS

1 km East of San Benedetto Ullano

50 months ago · 21 Jul, 00:34

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

Stronger than 23% of Italian events in the past year

Where

1 km East of San Benedetto UllanoEarthquakes 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

20 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 ≈ 21 s

Animation sped up ~4× compared to reality.

  • Cosenza
    20 km from the epicentre
    first tremor in ~4 s
    main shaking in ~7 s
  • Corigliano-Rossano
    35 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Lamezia Terme
    53 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Catanzaro
    72 km from the epicentre
    first tremor in ~12 s
    main shaking in ~21 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

11 km
medium depth
1.3 times the height of Mount Everest

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

shallower than the area average (~26 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: 50 months ago the same area had a stronger quake (M2.1). This can only be said after the fact — it was not predictable beforehand.

2.1
The mainshock
3 km South-West of Paterno Calabro
50 months ago · 25 Jul, 08:19
Activity in the area right now (30 km radius)
1
last 24 hours
1
last 7 days
13
last 30 days
6 before13 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~9 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 462 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 · 44 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
11846.8
Valle del Crati earthquake
24 May 1184 · 6 km from here
IXDestructive: many buildings partly or fully collapse.
18546.3
Cosentino earthquake
12 February 1854 · 23 km from here
XCompletely destructive: most buildings are destroyed.
18706.2
Cosentino earthquake
4 October 1870 · 28 km from here
XCompletely destructive: most buildings are destroyed.

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

The closest seismic structure

Crati Valley

The epicentre lies about 7 km from Crati Valley, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.6between 1 and 10 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

1.1
6 km North-East of Celico
27 km East · 30 km
50 months ago
22 Jul, 02:47
1.6
6 km North-East of Celico
27 km East · 28 km
50 months ago
19 Jul, 14:41
1.3
6 km North of Celico
27 km East · 30 km
50 months ago
19 Jul, 13:37
2.1
3 km South-West of Paterno Calabro
27 km South-East · 11 km
50 months ago
25 Jul, 08:19
1.3
3 km North of Malito
28 km South-East · 11 km
50 months ago
25 Jul, 08:23
0.9
4 km South of San Benedetto Ullano
3 km South-West · 20 km
50 months ago
16 Jul, 15:43
1.3
7 km North of Celico
24 km East · 32 km
50 months ago
14 Jul, 12:35
1.4
50 months ago
2 Aug, 13:34
0.5
50 months ago
3 Aug, 02:18
1.3
50 months ago
3 Aug, 04:14

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