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2.3
light
EARTHQUAKE DETAILS

M2.3 earthquake · 3 km North-West of Miglionico (MT)

8 years ago · 3 Apr 2018, 22:39

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 yearThe strongest of the past 12 months within 50 km

Where

3 km North-West of MiglionicoEarthquakes in the province of MateraEarthquakes 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

8 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 ≈ 18 s

Animation sped up ~3× compared to reality.

  • Matera
    15 km from the epicentre
    first tremor in ~4 s
    main shaking in ~7 s
  • Altamura
    28 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Bitonto
    52 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Potenza
    60 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

20 km
medium depth
2.2 times the height of Mount Everest

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

in line with the area average (~17 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 4 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
2
last 7 days
4
last 30 days
3 before4 after
this quake
Strongest of the sequence1.9

How often does it happen here?

about every ~35 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 123 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.

18465.2
Potentino earthquake
8 August 1846 · 33 km from here
VI-VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
18855.1
Basilicata earthquake
24 December 1885 · 10 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
16344.9
Matera earthquake
10 November 1634 · 12 km from here
VI-VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
19784.8
Materano earthquake
24 September 1978 · 6 km from here
VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.

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

The closest seismic structure

Baragiano-Palagianello

The epicentre lies about 5 km from Baragiano-Palagianello, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.4between 13 and 22 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

1.7
8 years ago
5 Apr 2018, 18:45
1.9
8 km East of Matera
19 km North-East · 1 km
8 years ago
28 Mar 2018, 10:35
1.7
6 km East of Matera
17 km North-East · 1 km
8 years ago
11 Apr 2018, 10:21
1.2
6 km North-West of Laterza
23 km East · 1 km
8 years ago
20 Apr 2018, 10:31
1.8
1 km South of Miglionico
4 km South · 21 km
8 years ago
24 Apr 2018, 18:05
1.5
6 km East of Matera
17 km North-East · 1 km
8 years ago
9 Mar 2018, 09:30
1.9
3 km East of Altamura
27 km North · 31 km
8 years ago
5 Mar 2018, 00:40

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).