All earthquakes
1.3
very light
EARTHQUAKE DETAILS

M1.3 earthquake · 3 km West of Ledro (TN)

4 years ago · 31 Aug 2022, 22:56

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

3 km West of LedroEarthquakes in the province of TrentoEarthquakes in Trentino-Alto Adige

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.

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 ≈ 22 s

Animation sped up ~4× compared to reality.

  • Trento
    38 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Brescia
    52 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Verona
    54 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Vicenza
    76 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 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 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 (~7 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 (M2.1). This can only be said after the fact — it was not predictable beforehand.

2.1
The mainshock
7 km South of Tignale
4 years ago · 18 Sept 2022, 05:00
Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
6
last 30 days
6 before9 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~30 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 142 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.

12225.7
Bresciano-Veronese earthquake
25 December 1222 · 38 km from here
19015.4
Garda occidentale earthquake
30 October 1901 · 35 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19325.2
Garda orientale earthquake
19 February 1932 · 27 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18825.1
Monte Baldo earthquake
18 September 1882 · 19 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.

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

The closest seismic structure

Giudicarie

The epicentre lies about 2 km from Giudicarie, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.8between 5 and 12 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

0.7
4 years ago
5 Sept 2022, 04:18
1.5
4 years ago
24 Aug 2022, 19:10
1.2
4 years ago
22 Aug 2022, 19:47
1.6
4 km North-West of Ala
29 km East · 10 km
4 years ago
20 Aug 2022, 09:49
1.2
4 km South of Rovereto
29 km East · 14 km
4 years ago
13 Sept 2022, 05:07
1.2
4 years ago
16 Sept 2022, 10:12
0.5
3 km East of Brentonico
24 km East · 18 km
4 years ago
17 Sept 2022, 11:29
2.1
7 km South of Tignale
19 km South · 8 km
4 years ago
18 Sept 2022, 05:00
1.3
6 km South of Tignale
18 km South · 9 km
4 years ago
18 Sept 2022, 06:26
1.1
7 km South of Tignale
19 km South · 10 km
4 years ago
18 Sept 2022, 11:49

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).