All earthquakes
1.1
very light
EARTHQUAKE DETAILS

M1.1 earthquake · 2 km South-East of Bronzolo (BZ)

5 years ago · 25 May 2021, 12:28

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 39% of Italian events in the past year

Where

2 km South-East of BronzoloEarthquakes in the province of BolzanoEarthquakes 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

30 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 ≈ 30 s

Animation sped up ~6× compared to reality.

  • Bolzano
    12 km from the epicentre
    first tremor in ~3 s
    main shaking in ~4 s
  • Trento
    42 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Vicenza
    94 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 s
  • Treviso
    106 km from the epicentre
    first tremor in ~18 s
    main shaking in ~30 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

10 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.

deeper than the area average (~4 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 (M1.2, 5 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

1.2
The mainshock
1 km South-West of Albiano
5 years ago · 24 May 2021, 18:10
Activity in the area right now (30 km radius)
2
last 24 hours
2
last 7 days
10
last 30 days
12 before17 after
this quake
Strongest of the sequence1.2

How often does it happen here?

about every ~8 months

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 17 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.

19025.0
Alpi Retiche earthquake
19 June 1902 · 49 km from here
VI-VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
20014.8
Val Venosta earthquake
17 July 2001 · 40 km from here
VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.
19804.0
Val Venosta earthquake
25 January 1980 · 41 km from here
V-VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.
17853.7
Val Lagarina earthquake
19 July 1785 · 49 km from here
VRather strong: felt by almost everyone; hanging objects swing.

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

The closest seismic structure

Giudicarie

The epicentre lies about 39 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

1.2
1 km South-West of Albiano
30 km South-West · 1 km
5 years ago
24 May 2021, 18:10
0.7
2 km North-West of Albiano
28 km South-West · 1 km
5 years ago
28 May 2021, 17:42
0.7
1 km East of Albiano
29 km South-West · 1 km
5 years ago
20 May 2021, 18:36
0.9
1 km South-East of Albiano
30 km South-West · 1 km
5 years ago
20 May 2021, 18:00
0.8
1 km South-East of Albiano
29 km South-West · 1 km
5 years ago
20 May 2021, 17:57
0.6
1 km North-West of Albiano
29 km South-West · 1 km
5 years ago
31 May 2021, 12:00
1.0
1 km North of Albiano
28 km South-West · 1 km
5 years ago
18 May 2021, 17:47
0.4
0 km North-West of Albiano
29 km South-West · 1 km
5 years ago
1 Jun 2021, 12:03
0.8
2 km West of Cembra Lisignago
25 km South-West · 1 km
5 years ago
1 Jun 2021, 12:15
1.1
1 km North-East of Cembra Lisignago
24 km South-West · 1 km
5 years ago
17 May 2021, 12:07

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).