All earthquakes
0.5
very light
EARTHQUAKE DETAILS

M0.5 earthquake · 1 km South-East of Sarconi (PZ)

9 years ago · 12 Jul 2017, 06:29

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 3% of Italian events in the past year

Where

1 km South-East of SarconiEarthquakes 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

19 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.1kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×5,623 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
    50 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Corigliano-Rossano
    79 km from the epicentre
    first tremor in ~13 s
    main shaking in ~23 s
  • Matera
    80 km from the epicentre
    first tremor in ~13 s
    main shaking in ~23 s
  • Altamura
    87 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

10 km
shallow
1.1 times the height of Mount Everest

At only a few km deep the shaking is felt more sharply at the surface.

shallower than 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?

Aftershock

It is an aftershock: it follows a stronger quake (M2.2, 9 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.2
The mainshock
6 km North of Montesano sulla Marcellana
9 years ago · 19 Jun 2017, 00:39
Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
9
last 30 days
13 before5 after
this quake
Strongest of the sequence2.2

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: 313 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 · 17 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
19775.9
Golfo di Policastro earthquake
30 December 1977 · 48 km from here
18365.9
Appennino lucano earthquake
20 November 1836 · 15 km from here
IXDestructive: many buildings partly or fully collapse.
12735.8
Potenza earthquake
18 December 1273 · 48 km from here
VIII-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 lies about 4 km from Rimendiello-Mormanno, one of the seismic structures mapped by INGV geologists.

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

0.5
1 km South-East of Lagonegro
14 km South-West · 12 km
9 years ago
12 Jul 2017, 03:27
0.3
2 km North-West of Paterno
25 km North-West · 7 km
9 years ago
10 Jul 2017, 03:27
1.4
5 km North-East of Marsico Nuovo
29 km North-West · 10 km
9 years ago
5 Jul 2017, 22:34
1.5
3 km West of Paterno
25 km North-West · 9 km
9 years ago
5 Jul 2017, 14:38
1.2
3 km North-West of Rivello
23 km South-West · 10 km
9 years ago
1 Jul 2017, 19:26
0.9
9 years ago
23 Jul 2017, 11:53
1.5
3 km South of Grumento Nova
6 km North-West · 17 km
9 years ago
30 Jun 2017, 00:35
1.1
4 km East of Spinoso
8 km East · 16 km
9 years ago
28 Jun 2017, 02:37
1.8
4 km East of Torraca
24 km South-West · 8 km
9 years ago
27 Jun 2017, 19:58
1.5
6 km East of Trecchina
22 km South-West · 9 km
9 years ago
26 Jun 2017, 12:10

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).