All earthquakes
1.3
very light
EARTHQUAKE DETAILS

M1.3 earthquake · 3 km North of Albi (CZ)

6 years ago · 25 Mar 2020, 17:03

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

3 km North of AlbiEarthquakes in the province of CatanzaroEarthquakes 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

42 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 ≈ 12 s

Animation sped up ~2× compared to reality.

  • Catanzaro
    20 km from the epicentre
    first tremor in ~4 s
    main shaking in ~6 s
  • Lamezia Terme
    31 km from the epicentre
    first tremor in ~5 s
    main shaking in ~9 s
  • Cosenza
    37 km from the epicentre
    first tremor in ~6 s
    main shaking in ~11 s
  • Crotone
    41 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 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?

Aftershock

It is an aftershock: it follows a stronger quake (M2.0, 6 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.0
The mainshock
4 km North of Albi
6 years ago · 29 Feb 2020, 18:05
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
13
last 30 days
23 before18 after
this quake
Strongest of the sequence2.0

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: 720 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 · 28 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17837.0
Calabria centrale earthquake
28 March 1783 · 35 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16386.8
Crotonese earthquake
8 June 1638 · 29 km from here
XCompletely destructive: most buildings are destroyed.
18326.7
Crotonese earthquake
8 March 1832 · 27 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

Ampollino Lake

The epicentre sits above this source area: the deep structure where this area's earthquakes can originate.

estimated maximum magnitude 7.1between 1 and 15 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

1.3
6 years ago
25 Mar 2020, 11:52
1.2
4 km South-East of Taverna
2 km North · 6 km
6 years ago
24 Mar 2020, 15:56
1.2
4 km North of Aprigliano
24 km North-West · 11 km
6 years ago
26 Mar 2020, 22:05
0.6
3 km North of Albi
0 km South-East · 9 km
6 years ago
21 Mar 2020, 23:40
1.1
3 km South-East of Taverna
2 km North · 7 km
6 years ago
30 Mar 2020, 00:11
1.6
3 km South-East of Taverna
2 km North-West · 7 km
6 years ago
20 Mar 2020, 18:32
0.6
6 years ago
1 Apr 2020, 04:06
1.1
4 km North of Albi
1 km North-West · 9 km
6 years ago
18 Mar 2020, 03:56
1.2
4 km North-East of Albi
1 km East · 9 km
6 years ago
17 Mar 2020, 16:55
0.9
4 km South-West of Cotronei
11 km North-East · 23 km
6 years ago
15 Mar 2020, 08:24

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).