All earthquakes
1.2
very light
EARTHQUAKE DETAILS

M1.2 earthquake · 0 km North of Concesio (BS)

8 years ago · 6 Jan 2018, 13:25

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

0 km North of ConcesioEarthquakes 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

6 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 ≈ 19 s

Animation sped up ~3× compared to reality.

  • Brescia
    9 km from the epicentre
    first tremor in ~2 s
    main shaking in ~4 s
  • Bergamo
    44 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 s
  • Cremona
    55 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Verona
    65 km from the epicentre
    first tremor in ~11 s
    main shaking in ~19 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?

Aftershock

It is an aftershock: it follows a stronger quake (M2.4, 8 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.4
The mainshock
1 km West of Collebeato
8 years ago · 26 Dec 2017, 17:48
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
1
last 30 days
4 before1 after
this quake
Strongest of the sequence2.4

How often does it happen here?

about every ~40 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 107 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 · 33 km from here
18025.6
Valle dell'Oglio earthquake
12 May 1802 · 36 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
19015.4
Garda occidentale earthquake
30 October 1901 · 21 km from here
VII-VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
16935.2
Mantovano earthquake
6 July 1693 · 50 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

Western S-Alps internal thrust

The epicentre lies about 2 km from Western S-Alps internal thrust, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.9between 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

1.9
2 km West of Gussago
7 km West · 9 km
8 years ago
1 Jan 2018, 19:14
2.3
1 km South-East of Caino
10 km East · 26 km
8 years ago
30 Dec 2017, 07:37
1.4
1 km East of Gussago
4 km West · 8 km
8 years ago
26 Dec 2017, 17:51
2.4
1 km West of Collebeato
3 km South-West · 7 km
8 years ago
26 Dec 2017, 17:48
1.2
3 km North-East of Idro
30 km North-East · 12 km
8 years ago
30 Jan 2018, 02:35

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).