All earthquakes
1.4
very light
EARTHQUAKE DETAILS

6 km North-West of Briatico

1 month ago · 21 Jul, 21:32

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 63% of Italian events in the past year

Where

6 km North-West of BriaticoEarthquakes in the province of Vibo ValentiaEarthquakes 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

9 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.9kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×251 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 ≈ 22 s

Animation sped up ~4× compared to reality.

  • Lamezia Terme
    34 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Catanzaro
    54 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Cosenza
    64 km from the epicentre
    first tremor in ~11 s
    main shaking in ~18 s
  • Messina
    75 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 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 (~43 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: 22 days ago the same area had a stronger quake (M2.2). This can only be said after the fact — it was not predictable beforehand.

2.2
The mainshock
15 km North of Briatico
22 days ago · 2 Aug, 20:33
Activity in the area right now (30 km radius)
1
last 24 hours
1
last 7 days
3
last 30 days
6 before2 after
this quake
Strongest of the sequence2.2

How often does it happen here?

about every ~5 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 916 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.

17837.1
Calabria meridionale earthquake
5 February 1783 · 50 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16387.1
Calabria centrale earthquake
27 March 1638 · 42 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17837.0
Calabria centrale earthquake
28 March 1783 · 41 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
19057.0
Calabria centrale earthquake
8 September 1905 · 7 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

Sant'Eufemia

The epicentre lies about 4 km from Sant'Eufemia, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.1between 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

0.7
3 km South of Gerocarne
28 km South-East · 13 km
1 month ago
17 Jul, 03:58
1.0
1 km East of Francica
18 km South-East · 16 km
1 month ago
15 Jul, 19:44
2.0
19 km North-West of Ricadi
28 km West · 94 km
1 month ago
14 Jul, 18:57
1.6
1 km North-East of Francica
18 km South-East · 16 km
1 month ago
14 Jul, 05:16
2.2
15 km North of Briatico
10 km North-East · 52 km
22 days ago
2 Aug, 20:33
1.8
10 km North-West of Pizzo
16 km North-East · 9 km
2 months ago
2 Jul, 20:36
2.2
23 km North-West of Tropea
28 km West · 157 km
10 days ago
15 Aug, 16:48
1.6
2 months ago
22 Jun, 22:30

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