All earthquakes
1.7
very light
EARTHQUAKE DETAILS

M1.7 earthquake · 1 km North of Prevalle (BS)

2 years ago · 11 Jul 2024, 21:58

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

1 km North of PrevalleEarthquakes in the province of BresciaEarthquakes in Lombardia

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

7 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 ≈ 18 s

Animation sped up ~3× compared to reality.

  • Brescia
    16 km from the epicentre
    first tremor in ~3 s
    main shaking in ~5 s
  • Verona
    47 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Cremona
    56 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Bergamo
    61 km from the epicentre
    first tremor in ~10 s
    main shaking in ~18 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.

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?

Aftershock

It is an aftershock: it follows a stronger quake (M2.3, 2 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.3
The mainshock
4 km South of Magasa
2 years ago · 20 Jun 2024, 22:48
Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
3
last 30 days
4 before2 after
this quake
Strongest of the sequence2.3

How often does it happen here?

about every ~38 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 113 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 · 16 km from here
18025.6
Valle dell'Oglio earthquake
12 May 1802 · 48 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
19015.4
Garda occidentale earthquake
30 October 1901 · 6 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
16935.2
Mantovano earthquake
6 July 1693 · 35 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 sits above this source area: the deep structure where this area's earthquakes can originate.

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

1.3
1 km North-East of Gargnano
22 km North-East · 11 km
2 years ago
23 Jul 2024, 02:17
1.7
2 km East of Nave
9 km West · 5 km
2 years ago
30 Jul 2024, 09:40
1.7
0 km South of Sulzano
28 km West · 8 km
2 years ago
22 Jun 2024, 01:13
2.3
4 km South of Magasa
27 km North-East · 10 km
2 years ago
20 Jun 2024, 22:48
1.5
3 km South-West of Botticino
10 km West · 10 km
2 years ago
19 Jun 2024, 11:06
1.3
5 km East of Gardone Riviera
17 km East · 10 km
2 years ago
13 Jun 2024, 15:54

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).