All earthquakes
1.5
very light
EARTHQUAKE DETAILS

M1.5 earthquake · 6 km West of Santa Severina (KR)

6 years ago · 19 Jul 2020, 00:35

A very light earthquake, probably not felt by people. Being deep, it is felt less at the surface.

Stronger than 69% of Italian events in the past year

Where

6 km West of Santa SeverinaEarthquakes in the province of CrotoneEarthquakes in Calabria

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

16 events
Magnitude:lightweakmoderatestrong

The energy released

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

2.7kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×178 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 ≈ 18 s

Animation sped up ~3× compared to reality.

  • Crotone
    21 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Catanzaro
    38 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Cosenza
    52 km from the epicentre
    first tremor in ~10 s
    main shaking in ~18 s
  • Lamezia Terme
    55 km from the epicentre
    first tremor in ~11 s
    main shaking in ~18 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

33 km
deep
3.8 times the height of Mount Everest

Being deep, it is felt less at the surface.

deeper than the area average (~18 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 (M1.8). This can only be said after the fact — it was not predictable beforehand.

1.8
The mainshock
2 km North-East of San Giovanni in Fiore
6 years ago · 11 Aug 2020, 06:13
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
4
last 30 days
6 before9 after
this quake
Strongest of the sequence1.8

How often does it happen here?

about every ~6 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 737 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.

16386.8
Crotonese earthquake
8 June 1638 · 13 km from here
XCompletely destructive: most buildings are destroyed.
18326.7
Crotonese earthquake
8 March 1832 · 12 km from here
XCompletely destructive: most buildings are destroyed.
18546.3
Cosentino earthquake
12 February 1854 · 49 km from here
XCompletely destructive: most buildings are destroyed.
18706.2
Cosentino earthquake
4 October 1870 · 46 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

Ampollino Lake

The epicentre lies about 17 km from Ampollino Lake, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.1between 1 and 15 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
6 years ago
19 Jul 2020, 07:04
1.1
7 km East of Aprigliano
28 km West · 8 km
6 years ago
15 Jul 2020, 09:39
1.0
4 km North-East of Albi
23 km West · 8 km
6 years ago
14 Jul 2020, 17:33
0.9
3 km North-East of Albi
24 km South-West · 9 km
6 years ago
12 Jul 2020, 03:49
0.8
3 km East of Taverna
22 km West · 4 km
6 years ago
25 Jul 2020, 22:55
1.6
11 km West of Cotronei
23 km West · 15 km
6 years ago
12 Jul 2020, 01:10
0.7
3 km East of Taverna
22 km West · 4 km
6 years ago
26 Jul 2020, 00:31
0.9
4 km North-East of Albi
23 km West · 9 km
6 years ago
12 Jul 2020, 00:29
1.1
3 km West of Umbriatico
21 km North · 29 km
6 years ago
11 Jul 2020, 10:24
0.8
3 km South-East of Taverna
24 km West · 5 km
6 years ago
1 Aug 2020, 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).