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2.8
light
EARTHQUAKE DETAILS

M2.8 earthquake · 2 km East of Feroleto Antico (CZ)

8 years ago · 9 May 2018, 10:17

A light earthquake, rarely felt by people. At only a few km deep the shaking is felt more sharply at the surface.

Stronger than 97% of Italian events in the past year

Where

2 km East of Feroleto AnticoEarthquakes in the province of CatanzaroEarthquakes in Calabria

How far away could it be felt?

An estimate of how far people may have felt this quake.

  • up to ~5 km · felt only by some, at rest
    ≈ 10,000 people live in this area

The coloured rings on the map below show these distances.

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

14 events
Magnitude:lightweakmoderatestrong

The energy released

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

239kgof TNT equivalent
1.0 lightning bolt
M3
A magnitude 3 earthquake releases ×2 its energy
M2this quakeM4

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.

  • Lamezia Terme
    11 km from the epicentre
    first tremor in ~3 s
    main shaking in ~4 s
  • Catanzaro
    17 km from the epicentre
    first tremor in ~3 s
    main shaking in ~6 s
  • Cosenza
    38 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Crotone
    61 km from the epicentre
    first tremor in ~10 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

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?

Mainshock

It is the strongest quake of its sequence: so far it has been followed by 10 aftershocks within 30 km. Aftershocks tend to fade in number and strength over time.

Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
28
last 30 days
3 before10 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~25 days

Within 50 km of this epicentre, a magnitude ≥ 2.5 earthquake has occurred on average this often: 174 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.

16387.1
Calabria centrale earthquake
27 March 1638 · 15 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17837.0
Calabria centrale earthquake
28 March 1783 · 19 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
19057.0
Calabria centrale earthquake
8 September 1905 · 39 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17836.7
Calabria centrale earthquake
7 February 1783 · 45 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.

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

The closest seismic structure

Caraffa-Squillace Gulf

The epicentre lies about 6 km from Caraffa-Squillace Gulf, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.9between 3 and 20 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

2.0
8 years ago
7 May 2018, 05:10
1.1
3 km West of Amato
1 km East · 9 km
8 years ago
11 May 2018, 19:04
0.9
3 km East of Feroleto Antico
1 km North-East · 9 km
8 years ago
14 May 2018, 04:36
2.1
1 km West of Cicala
10 km North-East · 27 km
8 years ago
14 May 2018, 06:14
0.9
2 km South-West of Rogliano
24 km North · 21 km
8 years ago
16 May 2018, 05:53
1.6
2 km South-West of Rogliano
24 km North · 24 km
8 years ago
16 May 2018, 06:36
1.6
8 years ago
16 May 2018, 08:09
1.5
8 years ago
16 May 2018, 16:23
1.6
2 km West of Rogliano
25 km North · 22 km
8 years ago
27 Apr 2018, 02:28
0.6
3 km North-West of Bianchi
17 km North · 22 km
8 years ago
26 Apr 2018, 08:22

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).