All earthquakes
1.6
very light
EARTHQUAKE DETAILS

M1.6 earthquake · 2 km North-West of Campolattaro (BN)

11 years ago · 2 May 2015, 21:47

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 74% of Italian events in the past year

Where

2 km North-West of CampolattaroEarthquakes in the province of BeneventoEarthquakes 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

22 events
Magnitude:lightweakmoderatestrong

The energy released

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

3.8kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×126 its energy
M1this quakeM3

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 ≈ 14 s

Animation sped up ~3× compared to reality.

  • Benevento
    18 km from the epicentre
    first tremor in ~3 s
    main shaking in ~6 s
  • Caserta
    41 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Avellino
    44 km from the epicentre
    first tremor in ~7 s
    main shaking in ~13 s
  • Acerra
    47 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 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 (~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?

Aftershock

It is an aftershock: it follows a stronger quake (M1.8, 11 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

1.8
The mainshock
2 km North-West of Pontelandolfo
11 years ago · 2 May 2015, 18:15
Activity in the area right now (30 km radius)
0
last 24 hours
4
last 7 days
7
last 30 days
8 before13 after
this quake
Strongest of the sequence1.8

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: 502 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.

14567.2
Appennino centro-meridionale earthquake
5 December 1456 · 1 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16887.1
Sannio earthquake
5 June 1688 · 14 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17326.8
Irpinia earthquake
29 November 1732 · 39 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
18056.7
Molise earthquake
26 July 1805 · 30 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

Miranda-Apice

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

estimated maximum magnitude 6.9between 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

1.5
11 years ago
2 May 2015, 18:31
1.8
2 km North-West of Pontelandolfo
3 km South-West · 10 km
11 years ago
2 May 2015, 18:15
1.4
3 km West of Campolattaro
1 km South-West · 11 km
11 years ago
3 May 2015, 01:23
1.1
3 km North of Campolattaro
3 km North-East · 10 km
11 years ago
1 May 2015, 06:45
1.2
11 years ago
1 May 2015, 03:40
1.5
11 years ago
1 May 2015, 03:36
1.4
11 years ago
1 May 2015, 01:26
1.2
3 km North of Pontelandolfo
2 km West · 10 km
11 years ago
30 Apr 2015, 21:53
1.2
1 km North-West of Campolattaro
1 km South-East · 11 km
11 years ago
5 May 2015, 00:16
1.1
11 years ago
27 Apr 2015, 11:18

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).