All earthquakes
1.1
very light
EARTHQUAKE DETAILS

M1.1 earthquake · 2 km South-East of Barrea (AQ)

9 years ago · 16 Jul 2017, 09:45

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

Stronger than 39% of Italian events in the past year

Where

2 km South-East of BarreaEarthquakes 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

25 events
Magnitude:lightweakmoderatestrong

The energy released

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

0.7kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×708 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 ≈ 24 s

Animation sped up ~4× compared to reality.

  • Chieti
    69 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 s
  • Caserta
    74 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • L'Aquila
    78 km from the epicentre
    first tremor in ~13 s
    main shaking in ~23 s
  • Pescara
    82 km from the epicentre
    first tremor in ~14 s
    main shaking in ~24 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

17 km
medium depth
2 times the height of Mount Everest

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

deeper than 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?

Aftershock

It is an aftershock: it follows a stronger quake (M3.2, 9 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

3.2
The mainshock
2 km South of Campo di Giove
9 years ago · 1 Jul 2017, 21:12
Activity in the area right now (30 km radius)
0
last 24 hours
9
last 7 days
25
last 30 days
16 before8 after
this quake
Strongest of the sequence3.2

How often does it happen here?

about every ~11 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 393 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 · 49 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
17066.8
Maiella earthquake
3 November 1706 · 38 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
13496.8
Lazio-Molise earthquake
9 September 1349 · 22 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
18056.7
Molise earthquake
26 July 1805 · 48 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

1.4
9 years ago
15 Jul 2017, 22:57
1.4
1 km South-East of Pesche
29 km South-East · 15 km
9 years ago
20 Jul 2017, 12:06
0.8
9 years ago
21 Jul 2017, 00:17
1.4
3 km East of Arpino
29 km West · 14 km
9 years ago
7 Jul 2017, 05:10
0.2
9 years ago
6 Jul 2017, 00:23
1.4
9 years ago
5 Jul 2017, 02:22
0.7
4 km South of Roccaraso
10 km North-East · 10 km
9 years ago
30 Jul 2017, 04:55
3.2
2 km South of Campo di Giove
27 km North · 8 km
9 years ago
1 Jul 2017, 21:12
1.1
3 km North-West of Bisegna
28 km North-West · 21 km
9 years ago
31 Jul 2017, 07:44
1.2
2 km West of Alvito
23 km West · 9 km
9 years ago
29 Jun 2017, 18:29

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).