All earthquakes
1.0
very light
EARTHQUAKE DETAILS

M1.0 earthquake · 5 km North-East of Sassinoro (BN)

5 years ago · 23 Nov 2020, 01:25

A very light earthquake, probably not felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 31% of Italian events in the past year

Where

5 km North-East of SassinoroEarthquakes 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

9 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.5kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×1,000 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 ≈ 17 s

Animation sped up ~3× compared to reality.

  • Benevento
    31 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Caserta
    46 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Acerra
    55 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 s
  • Avellino
    57 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 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

18 km
medium depth
2 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?

Aftershock

It is an aftershock: it follows a stronger quake (M2.4, 5 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.4
The mainshock
3 km South of Pietraroja
5 years ago · 1 Nov 2020, 17:08
Activity in the area right now (30 km radius)
0
last 24 hours
6
last 7 days
9
last 30 days
4 before4 after
this quake
Strongest of the sequence2.4

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: 477 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 · 13 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16887.1
Sannio earthquake
5 June 1688 · 18 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
18056.7
Molise earthquake
26 July 1805 · 20 km from here
XCompletely destructive: most buildings are destroyed.
17026.6
Sannio-Irpinia earthquake
14 March 1702 · 42 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 lies about 2 km from Miranda-Apice, one of the seismic structures mapped by INGV geologists.

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

1.4
3 km East of Pietraroja
9 km South-West · 11 km
5 years ago
24 Nov 2020, 22:40
1.3
2 km South-West of Celenza Valfortore
29 km North-East · 23 km
5 years ago
20 Nov 2020, 10:41
1.5
5 years ago
18 Nov 2020, 14:03
1.3
5 years ago
30 Nov 2020, 13:47
1.9
2 km West of Cusano Mutri
18 km West · 3 km
5 years ago
12 Dec 2020, 03:40
1.1
5 years ago
3 Nov 2020, 04:37
2.4
3 km South of Pietraroja
14 km South-West · 14 km
5 years ago
1 Nov 2020, 17:08
1.4
2 km South of Ripabottoni
30 km North-East · 20 km
5 years ago
19 Dec 2020, 07:30

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).