All earthquakes
1.4
very light
EARTHQUAKE DETAILS

M1.4 earthquake · 3 km North-West of Laviano (SA)

4 years ago · 19 Nov 2021, 09:26

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

3 km North-West of LavianoEarthquakes in the province of SalernoEarthquakes in Campania

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

16 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 ≈ 13 s

Animation sped up ~2× compared to reality.

  • Battipaglia
    37 km from the epicentre
    first tremor in ~6 s
    main shaking in ~11 s
  • Potenza
    44 km from the epicentre
    first tremor in ~7 s
    main shaking in ~13 s
  • Salerno
    45 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 s
  • Avellino
    46 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 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

7 km
shallow

At only a few km deep the shaking is felt more sharply at the surface.

shallower than the area average (~15 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 (M2.4, 4 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.4
The mainshock
1 km North-West of Valva
4 years ago · 4 Nov 2021, 06:06
Activity in the area right now (30 km radius)
0
last 24 hours
3
last 7 days
12
last 30 days
11 before4 after
this quake
Strongest of the sequence2.4

How often does it happen here?

about every ~11 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 380 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.

19806.8
Irpinia-Basilicata earthquake
23 November 1980 · 6 km from here
XCompletely destructive: most buildings are destroyed.
17326.8
Irpinia earthquake
29 November 1732 · 37 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16946.7
Irpinia-Basilicata earthquake
8 September 1694 · 11 km from here
XCompletely destructive: most buildings are destroyed.
15616.7
Vallo di Diano earthquake
19 August 1561 · 30 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

Irpinia-Agri Valley

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

estimated maximum magnitude 6.8between 1 and 14 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

0.9
4 years ago
18 Nov 2021, 21:25
1.4
2 km South of Castelgrande
11 km East · 6 km
4 years ago
18 Nov 2021, 17:43
0.9
1 km East of Laviano
4 km East · 13 km
4 years ago
22 Nov 2021, 01:45
2.0
4 years ago
16 Nov 2021, 00:39
1.0
2 km South of Laviano
4 km South-East · 11 km
4 years ago
15 Nov 2021, 11:53
1.1
3 km West of Vietri di Potenza
25 km South-East · 17 km
4 years ago
30 Nov 2021, 19:48
1.7
4 years ago
7 Nov 2021, 20:22
1.2
4 years ago
5 Nov 2021, 06:46
2.4
1 km North-West of Valva
6 km South-West · 9 km
4 years ago
4 Nov 2021, 06:06
0.9
1 km South-West of Salvitelle
25 km South-East · 12 km
4 years ago
1 Nov 2021, 14:38

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).