All earthquakes
1.7
very light
EARTHQUAKE DETAILS

M1.7 earthquake · 2 km South of Palata (CB)

8 years ago · 18 Aug 2018, 14:26

A very light earthquake, probably not felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 78% of Italian events in the past year

Where

2 km South of PalataEarthquakes in the province of CampobassoEarthquakes in Molise

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

61 events
Magnitude:lightweakmoderatestrong

The energy released

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

5.4kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×89 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 ≈ 23 s

Animation sped up ~4× compared to reality.

  • San Severo
    62 km from the epicentre
    first tremor in ~11 s
    main shaking in ~19 s
  • Foggia
    79 km from the epicentre
    first tremor in ~13 s
    main shaking in ~23 s
  • Benevento
    79 km from the epicentre
    first tremor in ~14 s
    main shaking in ~23 s
  • Chieti
    79 km from the epicentre
    first tremor in ~14 s
    main shaking in ~23 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

18 km
medium depth
2 times the height of Mount Everest

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

in line with 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 (M5.1, 8 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

5.1
The mainshock
3 km East of Palata
8 years ago · 16 Aug 2018, 20:19
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
2
last 30 days
199 before397 after
this quake
Strongest of the sequence5.1

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: 448 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.

18056.7
Molise earthquake
26 July 1805 · 50 km from here
XCompletely destructive: most buildings are destroyed.
16276.7
Capitanata earthquake
30 July 1627 · 44 km from here
XCompletely destructive: most buildings are destroyed.
16276.0
Capitanata earthquake
7 August 1627 · 42 km from here
IXDestructive: many buildings partly or fully collapse.
16576.0
Capitanata earthquake
29 January 1657 · 49 km from here
IX-XCompletely destructive: most buildings are destroyed.

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

The closest seismic structure

Ripabottoni-San Severo

The epicentre lies about 17 km from Ripabottoni-San Severo, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.1between 6 and 25 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

1.8
3 km South of Palata
1 km South-West · 19 km
8 years ago
18 Aug 2018, 14:11
1.2
2 km South-East of Palata
1 km East · 17 km
8 years ago
18 Aug 2018, 14:10
0.6
4 km West of Larino
3 km East · 16 km
8 years ago
18 Aug 2018, 15:09
1.6
1 km South of Palata
1 km North-West · 19 km
8 years ago
18 Aug 2018, 13:02
1.5
3 km South-West of Palata
1 km West · 18 km
8 years ago
18 Aug 2018, 12:45
1.5
2 km South of Palata
1 km South-West · 14 km
8 years ago
18 Aug 2018, 12:43
1.2
3 km South of Palata
2 km South-West · 10 km
8 years ago
18 Aug 2018, 12:28
1.3
2 km South of Palata
1 km West · 12 km
8 years ago
18 Aug 2018, 12:22
1.3
3 km South-East of Palata
1 km East · 17 km
8 years ago
18 Aug 2018, 12:19
1.2
3 km South-East of Palata
2 km South-East · 14 km
8 years ago
18 Aug 2018, 12:15

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).