All earthquakes
1.2
very light
EARTHQUAKE DETAILS

M1.2 earthquake · 5 km North-East of Silandro (BZ)

2 years ago · 7 Dec 2023, 04:38

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 48% of Italian events in the past year

Where

5 km North-East of SilandroEarthquakes 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

8 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.0kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×501 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 ≈ 40 s

Animation sped up ~7× compared to reality.

  • Bolzano
    50 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Trento
    75 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Brescia
    136 km from the epicentre
    first tremor in ~23 s
    main shaking in ~39 s
  • Vicenza
    139 km from the epicentre
    first tremor in ~23 s
    main shaking in ~40 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

8 km
shallow

At only a few km deep the shaking is felt more sharply at the surface.

in line with the area average (~10 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: 2 years ago the same area had a stronger quake (M1.6). This can only be said after the fact — it was not predictable beforehand.

1.6
The mainshock
2 km North-East of Glorenza
2 years ago · 11 Dec 2023, 23:26
Activity in the area right now (30 km radius)
0
last 24 hours
1
last 7 days
7
last 30 days
4 before3 after
this quake
Strongest of the sequence1.6

How often does it happen here?

about every ~3 months

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 42 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.

16225.4
Bassa Engadina, Ftan earthquake
3 August 1622 · 45 km from here
19245.2
Tirolo earthquake
26 March 1924 · 49 km from here
IIILight: felt by few people, like a passing truck.
19025.0
Alpi Retiche earthquake
19 June 1902 · 39 km from here
VI-VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
19614.9
Val Monastero earthquake
9 August 1961 · 36 km from here
V-VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.

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

The closest seismic structure

Brenner

The epicentre lies about 44 km from Brenner, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.2between 4 and 15 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

1.6
2 km North-East of Glorenza
17 km West · 11 km
2 years ago
11 Dec 2023, 23:26
1.3
2 km North-East of Glorenza
17 km West · 11 km
2 years ago
11 Dec 2023, 23:27
1.2
5 km West of San Pancrazio
21 km South-East · 10 km
2 years ago
27 Nov 2023, 10:19
0.7
7 km North of Silandro
4 km North-West · 12 km
2 years ago
19 Dec 2023, 17:07
0.9
7 km West of Ultimo
22 km South · 3 km
2 years ago
17 Nov 2023, 16:28
1.3
3 km South-East of Lasa
14 km South-West · 10 km
2 years ago
14 Nov 2023, 22:04
1.2
5 km South-East of Tubre
25 km West · 10 km
2 years ago
10 Nov 2023, 21:08

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).