All earthquakes
1.9
very light
EARTHQUAKE DETAILS

M1.9 earthquake · 1 km West of Bonefro (CB)

6 years ago · 3 Jul 2020, 16:17

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

Stronger than 85% of Italian events in the past year

Where

1 km West of BonefroEarthquakes 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

16 events
Magnitude:lightweakmoderatestrong

The energy released

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

11kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×45 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
    51 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Benevento
    64 km from the epicentre
    first tremor in ~11 s
    main shaking in ~19 s
  • Foggia
    65 km from the epicentre
    first tremor in ~11 s
    main shaking in ~20 s
  • Manfredonia
    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

20 km
medium depth
2.3 times the height of Mount Everest

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

in line with the area average (~15 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 (M3.5, 6 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

3.5
The mainshock
1 km North of Palata
6 years ago · 29 Jun 2020, 18:21
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
2
last 30 days
7 before8 after
this quake
Strongest of the sequence3.5

How often does it happen here?

about every ~9 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 481 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.

14567.2
Appennino centro-meridionale earthquake
5 December 1456 · 48 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
18056.7
Molise earthquake
26 July 1805 · 43 km from here
XCompletely destructive: most buildings are destroyed.
16276.7
Capitanata earthquake
30 July 1627 · 36 km from here
XCompletely destructive: most buildings are destroyed.
16276.0
Capitanata earthquake
7 August 1627 · 35 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

Ripabottoni-San Severo

The epicentre lies about 1 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

1.0
2 km South of San Marco la Catola
25 km South-East · 22 km
6 years ago
1 Jul 2020, 23:47
1.8
2 km North-West of Palata
21 km North-West · 19 km
6 years ago
5 Jul 2020, 16:25
1.3
6 years ago
6 Jul 2020, 19:36
1.6
6 years ago
7 Jul 2020, 00:05
3.5
1 km North of Palata
20 km North-West · 18 km
6 years ago
29 Jun 2020, 18:21
1.5
1 km South-West of Jelsi
24 km South-West · 23 km
6 years ago
29 Jun 2020, 05:31
1.0
6 years ago
17 Jul 2020, 04:29
1.3
3 km West of Volturara Appula
28 km South-East · 22 km
6 years ago
17 Jul 2020, 09:10
1.6
2 km South of Ururi
13 km North-East · 15 km
6 years ago
19 Jun 2020, 14:26
1.3
2 km North-East of Palata
20 km North · 20 km
6 years ago
18 Jul 2020, 17:25

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).