All earthquakes
1.0
very light
EARTHQUAKE DETAILS

M1.0 earthquake · 4 km East of Padula (SA)

7 years ago · 19 Sept 2019, 21:28

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

4 km East of PadulaEarthquakes 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

23 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 ≈ 25 s

Animation sped up ~5× compared to reality.

  • Potenza
    38 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Battipaglia
    70 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 s
  • Salerno
    86 km from the epicentre
    first tremor in ~15 s
    main shaking in ~25 s
  • Matera
    88 km from the epicentre
    first tremor in ~15 s
    main shaking in ~25 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

16 km
medium depth
1.8 times the height of Mount Everest

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

in line with the area average (~16 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?

Foreshock

In hindsight it was a foreshock: 6 years ago the same area had a stronger quake (M2.7). This can only be said after the fact — it was not predictable beforehand.

2.7
The mainshock
4 km East of Pignola
6 years ago · 14 Oct 2019, 19:37
Activity in the area right now (30 km radius)
0
last 24 hours
3
last 7 days
13
last 30 days
8 before14 after
this quake
Strongest of the sequence2.7

How often does it happen here?

about every ~12 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 358 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.

18577.1
Basilicata earthquake
16 December 1857 · 12 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
15616.7
Vallo di Diano earthquake
19 August 1561 · 31 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
15616.3
Vallo di Diano earthquake
31 July 1561 · 45 km from here
IX-XCompletely destructive: most buildings are destroyed.
19775.9
Golfo di Policastro earthquake
30 December 1977 · 44 km from here

Source: Parametric Catalogue of Italian Earthquakes CPTI15 (INGV, CC BY 4.0).

The closest seismic structure

Irpinia-Agri Valley

The epicentre lies about 3 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

1.2
4 km South of Grumento Nova
18 km East · 18 km
7 years ago
20 Sept 2019, 17:46
1.4
2 km North-East of Corleto Monforte
29 km North-West · 11 km
7 years ago
17 Sept 2019, 18:13
1.1
6 km North-East of Nemoli
26 km South-East · 9 km
7 years ago
17 Sept 2019, 07:23
0.8
6 km North-East of Nemoli
25 km South-East · 10 km
7 years ago
17 Sept 2019, 07:17
0.6
7 km North-West of Lauria
26 km South-East · 11 km
7 years ago
17 Sept 2019, 03:30
1.0
4 km West of Anzi
26 km North-East · 13 km
7 years ago
26 Sept 2019, 11:27
1.1
5 km East of Sapri
29 km South · 10 km
7 years ago
13 Sept 2019, 04:23
1.7
5 km East of Sapri
28 km South · 10 km
7 years ago
13 Sept 2019, 04:22
0.4
5 km South-West of San Rufo
20 km West · 10 km
7 years ago
29 Sept 2019, 00:02
1.3
7 years ago
5 Oct 2019, 05:42

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).