All earthquakes
3.4
weak
EARTHQUAKE DETAILS

M3.4 earthquake · 2 km South-East of Nusco (AV)

6 years ago · 15 Apr 2020, 07:35

A weak earthquake, felt by some of the population. At this depth the shaking is felt, but rarely causes damage.

No. 8 of the month in ItalyStronger than 99% of Italian events in the past year

Where

2 km South-East of NuscoEarthquakes in the province of AvellinoEarthquakes in Campania

How far away could it be felt?

An estimate of how far people may have felt this quake.

  • up to ~20 km · felt only by some, at rest
    ≈ 98,000 people live in this area

The coloured rings on the map below show these distances.

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

14 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.9tof TNT equivalent
7.9 lightning bolts
M3
×4 the energy of a magnitude 3 earthquake
M2this quakeM4

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.

  • Avellino
    27 km from the epicentre
    first tremor in ~5 s
    main shaking in ~9 s
  • Battipaglia
    33 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Salerno
    34 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Cava de' Tirreni
    39 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

12 km
medium depth
1.3 times the height of Mount Everest

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

in line with the area average (~14 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?

Mainshock

It is the strongest quake of its sequence: so far it has been followed by 11 aftershocks within 30 km. Aftershocks tend to fade in number and strength over time.

Activity in the area right now (30 km radius)
0
last 24 hours
5
last 7 days
14
last 30 days
2 before11 after
this quake
Strongest of the sequence3.0

How often does it happen here?

about every ~3 months

Within 50 km of this epicentre, a magnitude ≥ 3 earthquake has occurred on average this often: 51 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 · 14 km from here
XCompletely destructive: most buildings are destroyed.
17326.8
Irpinia earthquake
29 November 1732 · 22 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16946.7
Irpinia-Basilicata earthquake
8 September 1694 · 25 km from here
XCompletely destructive: most buildings are destroyed.
15616.7
Vallo di Diano earthquake
19 August 1561 · 47 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 lies about 2 km from Irpinia-Agri Valley, one of the seismic structures mapped by INGV geologists.

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

3.0
2 km South-East of Nusco
0 km North-East · 11 km
6 years ago
15 Apr 2020, 18:38
1.6
6 years ago
8 Apr 2020, 19:01
1.7
1 km South of Paternopoli
11 km North-West · 11 km
6 years ago
24 Apr 2020, 12:11
1.5
1 km East of Pescopagano
25 km East · 15 km
6 years ago
6 Apr 2020, 01:24
1.4
1 km South-East of Caposele
12 km South-East · 11 km
6 years ago
25 Apr 2020, 02:24
1.9
0 km South-West of Scampitella
30 km North-East · 13 km
6 years ago
1 May 2020, 21:41
2.1
1 km North-West of Scampitella
30 km North-East · 15 km
6 years ago
1 May 2020, 21:52
1.7
2 km South-West of Caposele
11 km South-East · 13 km
6 years ago
2 May 2020, 00:56
2.1
3 km South-West of Caposele
12 km South-East · 14 km
6 years ago
2 May 2020, 01:03
1.0
2 km South of Caposele
12 km South-East · 12 km
6 years ago
2 May 2020, 01:07

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).