All earthquakes
1.3
very light
EARTHQUAKE DETAILS

M1.3 earthquake · 2 km West of Rivisondoli (AQ)

8 years ago · 12 Nov 2017, 17:35

A very light earthquake, probably not felt by people. At only a few km deep the shaking is felt more sharply at the surface.

Stronger than 55% of Italian events in the past year

Where

2 km West of RivisondoliEarthquakes in the province of L'AquilaEarthquakes in Abruzzo

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.

1.3kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×355 its energy
M0this quakeM2

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 ≈ 21 s

Animation sped up ~4× compared to reality.

  • Chieti
    55 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Pescara
    68 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 s
  • Montesilvano
    70 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 s
  • L'Aquila
    71 km from the epicentre
    first tremor in ~12 s
    main shaking in ~21 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

9 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.

in line with the area average (~12 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: 8 years ago the same area had a stronger quake (M2.9). This can only be said after the fact — it was not predictable beforehand.

2.9
The mainshock
1 km South of Vastogirardi
8 years ago · 29 Nov 2017, 22:30
Activity in the area right now (30 km radius)
4
last 24 hours
6
last 7 days
19
last 30 days
14 before90 after
this quake
Strongest of the sequence2.9

How often does it happen here?

about every ~12 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 358 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.

19157.1
Marsica earthquake
13 January 1915 · 46 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17066.8
Maiella earthquake
3 November 1706 · 24 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
13496.8
Lazio-Molise earthquake
9 September 1349 · 36 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
16546.3
Sorano earthquake
24 July 1654 · 39 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

Borbona-L'Aquila-Aremogna

The epicentre sits above this source area: the deep structure where this area's earthquakes can originate.

estimated maximum magnitude 7.0between 2 and 14 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

1.3
3 km West of Pescocostanzo
6 km North · 15 km
8 years ago
12 Nov 2017, 16:48
0.8
5 km West of Scanno
16 km West · 23 km
8 years ago
18 Nov 2017, 05:47
0.6
8 years ago
4 Nov 2017, 19:49
1.1
8 years ago
4 Nov 2017, 12:20
0.9
8 years ago
4 Nov 2017, 11:25
1.2
2 km South-West of Vastogirardi
22 km South-East · 16 km
8 years ago
21 Nov 2017, 04:40
0.8
8 years ago
4 Nov 2017, 00:09
0.8
4 km South-East of Cansano
10 km North · 9 km
8 years ago
1 Nov 2017, 18:16
1.2
3 km West of Rivisondoli
1 km North-West · 23 km
8 years ago
1 Nov 2017, 09:34
0.9
1 km West of Gioia dei Marsi
27 km West · 18 km
8 years ago
1 Nov 2017, 07:29

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).