All earthquakes
1.4
very light
EARTHQUAKE DETAILS

M1.4 earthquake · 3 km South of Rotonda (PZ)

10 years ago · 2 May 2016, 19:35

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 South of RotondaEarthquakes in the province of PotenzaEarthquakes in Basilicata

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

24 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 ≈ 29 s

Animation sped up ~5× compared to reality.

  • Corigliano-Rossano
    45 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 s
  • Cosenza
    72 km from the epicentre
    first tremor in ~12 s
    main shaking in ~21 s
  • Potenza
    87 km from the epicentre
    first tremor in ~15 s
    main shaking in ~25 s
  • Matera
    101 km from the epicentre
    first tremor in ~17 s
    main shaking in ~29 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 (~20 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 (M2.8, 10 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.8
The mainshock
4 km South-East of Santa Domenica Talao
10 years ago · 16 Apr 2016, 00:00
Activity in the area right now (30 km radius)
0
last 24 hours
1
last 7 days
12
last 30 days
15 before8 after
this quake
Strongest of the sequence2.8

How often does it happen here?

about every ~14 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 310 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.

18365.9
Appennino lucano earthquake
20 November 1836 · 36 km from here
IXDestructive: many buildings partly or fully collapse.
19135.6
Calabria settentrionale earthquake
28 June 1913 · 44 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
17085.6
Pollino earthquake
26 January 1708 · 5 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
18875.5
Calabria settentrionale earthquake
3 December 1887 · 40 km from here
IXDestructive: many buildings partly or fully collapse.

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

The closest seismic structure

Rimendiello-Mormanno

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

estimated maximum magnitude 6.6between 1 and 12 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

1.1
4 km South of Scalea
26 km South-West · 10 km
10 years ago
4 May 2016, 21:21
1.8
3 km South of Castelsaraceno
28 km North · 24 km
10 years ago
7 May 2016, 00:54
1.3
10 years ago
7 May 2016, 03:13
1.7
10 years ago
19 Apr 2016, 06:04
1.9
0 km North of Castrovillari
17 km South-East · 8 km
10 years ago
18 Apr 2016, 00:20
1.3
2 km East of Castelluccio Superiore
16 km North-West · 10 km
10 years ago
17 Apr 2016, 19:22
2.8
4 km South-East of Santa Domenica Talao
19 km South-West · 277 km
10 years ago
16 Apr 2016, 00:00
1.5
2 km South-East of Laino Borgo
11 km North-West · 10 km
10 years ago
14 Apr 2016, 06:08
1.5
10 years ago
12 Apr 2016, 03:20
1.8
3 km North of Santa Maria del Cedro
24 km South-West · 49 km
10 years ago
24 May 2016, 05:35

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).