All earthquakes
1.1
very light
EARTHQUAKE DETAILS

M1.1 earthquake · 3 km South-East of Capracotta (IS)

4 years ago · 7 Nov 2021, 04:36

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

3 km South-East of CapracottaEarthquakes in the province of IserniaEarthquakes 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

10 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 ≈ 23 s

Animation sped up ~4× compared to reality.

  • Chieti
    63 km from the epicentre
    first tremor in ~11 s
    main shaking in ~19 s
  • Pescara
    74 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Caserta
    76 km from the epicentre
    first tremor in ~13 s
    main shaking in ~23 s
  • Montesilvano
    77 km from the epicentre
    first tremor in ~13 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

22 km
medium depth
2.4 times the height of Mount Everest

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

deeper than the area average (~14 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: 4 years ago the same area had a stronger quake (M2.0). This can only be said after the fact — it was not predictable beforehand.

2.0
The mainshock
4 km East of Trivento
4 years ago · 15 Nov 2021, 09:33
Activity in the area right now (30 km radius)
7
last 24 hours
10
last 7 days
23
last 30 days
5 before4 after
this quake
Strongest of the sequence2.0

How often does it happen here?

about every ~8 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 528 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.

17066.8
Maiella earthquake
3 November 1706 · 36 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
13496.8
Lazio-Molise earthquake
9 September 1349 · 40 km from here
X-XICatastrophic: very few buildings remain standing; landslides and ground cracks.
18056.7
Molise earthquake
26 July 1805 · 36 km from here
XCompletely destructive: most buildings are destroyed.
19335.9
Maiella earthquake
26 September 1933 · 36 km from here
IXDestructive: many buildings partly or fully collapse.

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

The closest seismic structure

Deep Abruzzo Citeriore Basal Thrust

The epicentre lies about 2 km from Deep Abruzzo Citeriore Basal Thrust, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.5between 8 and 18 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
3 km South-East of Rocca Pia
26 km West · 10 km
4 years ago
12 Nov 2021, 04:57
0.7
1 km West of Pesche
20 km South · 11 km
4 years ago
31 Oct 2021, 02:57
1.9
2 km West of Capracotta
4 km North-West · 16 km
4 years ago
30 Oct 2021, 15:06
1.5
4 years ago
15 Nov 2021, 04:01
2.0
4 km East of Trivento
27 km East · 18 km
4 years ago
15 Nov 2021, 09:33
2.0
4 km North-East of San Biase
27 km East · 19 km
4 years ago
15 Nov 2021, 09:59
1.4
3 km West of Vastogirardi
6 km West · 19 km
4 years ago
19 Oct 2021, 03:13
1.2
3 km South of Rionero Sannitico
16 km South-West · 13 km
4 years ago
16 Oct 2021, 21:45
1.7
4 km South of Capracotta
2 km South-West · 19 km
4 years ago
14 Oct 2021, 11:01

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).