All earthquakes
1.7
very light
EARTHQUAKE DETAILS

M1.7 earthquake · 4 km East of Rovereto (TN)

9 years ago · 9 Apr 2017, 09:45

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 78% of Italian events in the past year

Where

4 km East of RoveretoEarthquakes 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

11 events
Magnitude:lightweakmoderatestrong

The energy released

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

5.4kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×89 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 ≈ 21 s

Animation sped up ~4× compared to reality.

  • Trento
    21 km from the epicentre
    first tremor in ~4 s
    main shaking in ~7 s
  • Verona
    47 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Vicenza
    50 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Bolzano
    73 km from the epicentre
    first tremor in ~12 s
    main shaking in ~21 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: 9 years ago the same area had a stronger quake (M1.9). This can only be said after the fact — it was not predictable beforehand.

1.9
The mainshock
4 km South of Limone sul Garda
9 years ago · 11 Apr 2017, 10:47
Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
6
last 30 days
4 before6 after
this quake
Strongest of the sequence1.9

How often does it happen here?

about every ~34 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 126 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.

18915.9
Valle d'Illasi earthquake
7 June 1891 · 34 km from here
IXDestructive: many buildings partly or fully collapse.
19325.2
Garda orientale earthquake
19 February 1932 · 38 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
18825.1
Monte Baldo earthquake
18 September 1882 · 30 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
18765.1
Monte Baldo earthquake
29 April 1876 · 27 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.

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

The closest seismic structure

Schio-Vicenza

The epicentre lies about 7 km from Schio-Vicenza, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.3between 1 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
4 km West of Terragnolo
2 km North-East · 10 km
9 years ago
9 Apr 2017, 09:49
1.9
9 years ago
11 Apr 2017, 10:47
0.8
2 km East of Civezzano
29 km North-East · 1 km
9 years ago
11 Apr 2017, 12:47
0.7
1 km South-East of Volano
5 km North · 12 km
9 years ago
15 Apr 2017, 00:40
1.2
3 km South of Pedemonte
19 km East · 16 km
9 years ago
2 Apr 2017, 17:56
1.0
4 km West of Vallarsa
7 km South · 15 km
9 years ago
25 Mar 2017, 05:48
0.5
5 km North of Avio
16 km South-West · 14 km
9 years ago
20 Mar 2017, 09:17
0.8
4 km North-East of Ala
10 km South · 9 km
9 years ago
3 May 2017, 12:42
1.4
2 km North-East of Ala
13 km South · 10 km
9 years ago
13 Mar 2017, 14:26
1.2
1 km South-East of Vallarsa
8 km South-East · 11 km
9 years ago
7 May 2017, 19:23

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).