All earthquakes
2.3
light
EARTHQUAKE DETAILS

M2.3 offshore earthquake

10 years ago · 2 Jan 2016, 02:56

A light earthquake, rarely felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 93% of Italian events in the past year

Where

Nearest Italian town: Bova Marina (RC)Earthquakes in the province of Reggio CalabriaEarthquakes in Calabria

Epicentre at sea

The epicentre is at sea: for the same magnitude, the shaking is felt less on land, because the energy fades along the way before reaching the coast.

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

7 events
Magnitude:lightweakmoderatestrong

The energy released

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

43kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×11 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 ≈ 26 s

Animation sped up ~5× compared to reality.

  • Reggio di Calabria
    48 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Messina
    65 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 s
  • Acireale
    70 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Catania
    85 km from the epicentre
    first tremor in ~15 s
    main shaking in ~26 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

29 km
medium depth
3.3 times the height of Mount Everest

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

deeper than the area average (~21 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: 10 years ago the same area had a stronger quake (M2.6). This can only be said after the fact — it was not predictable beforehand.

2.6
The mainshock
Mar Ionio Meridionale [Mare]
10 years ago · 30 Jan 2016, 18:25
Activity in the area right now (30 km radius)
0
last 24 hours
1
last 7 days
2
last 30 days
2 before4 after
this quake
Strongest of the sequence2.6

How often does it happen here?

about every ~10 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 453 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.

19076.0
Aspromonte earthquake
23 October 1907 · 41 km from here
IXDestructive: many buildings partly or fully collapse.
15095.6
Stretto di Messina earthquake
25 February 1509 · 49 km from here
IXDestructive: many buildings partly or fully collapse.
19785.2
Aspromonte earthquake
11 March 1978 · 39 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19635.0
Ionio meridionale earthquake
30 September 1963 · 28 km from here

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

The closest seismic structure

Artemide

The epicentre lies about 33 km from Artemide, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.2between 11 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

2.4
Costa Calabra sud-orientale (Reggio di Calabria)
22 km East · 39 km
10 years ago
4 Jan 2016, 00:55
2.3
19 km South of Palizzi
14 km North-East · 23 km
10 years ago
11 Jan 2016, 02:07
1.7
10 years ago
21 Dec 2015, 10:39
1.6
Mar Ionio Meridionale [Mare]
25 km West · 21 km
10 years ago
29 Jan 2016, 02:19
2.6
Mar Ionio Meridionale [Mare]
27 km South-West · 32 km
10 years ago
30 Jan 2016, 18:25
2.2
10 years ago
4 Dec 2015, 01:49

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).