All earthquakes
1.2
very light
EARTHQUAKE DETAILS

M1.2 earthquake · 2 km West of Villa d'Ogna (BG)

7 years ago · 19 Mar 2019, 23:58

A very light earthquake, probably not felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 48% of Italian events in the past year

Where

2 km West of Villa d'OgnaEarthquakes in the province of BergamoEarthquakes 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

4 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 ~4× compared to reality.

  • Bergamo
    30 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Brescia
    48 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Monza
    60 km from the epicentre
    first tremor in ~11 s
    main shaking in ~18 s
  • Como
    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

18 km
medium depth
2 times the height of Mount Everest

At this depth the shaking is felt, but rarely causes damage.

deeper than the area average (~9 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 (M1.4, 7 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

1.4
The mainshock
1 km South-West of Castro
7 years ago · 5 Mar 2019, 01:33
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
0
last 30 days
2 before1 after
this quake
Strongest of the sequence1.4

How often does it happen here?

about every ~2 months

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 61 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.

10655.1
Brescia earthquake
27 March 1065 · 47 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19185.0
Lecchese earthquake
24 April 1918 · 37 km from here
VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.
18944.9
Bresciano earthquake
27 November 1894 · 42 km from here
VIStrong: felt by everyone, many get scared; objects fall, first light damage to buildings.
19614.9
Prealpi bergamasche earthquake
23 November 1961 · 30 km from here

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 27 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

1.4
1 km South-West of Castro
17 km South-East · 12 km
7 years ago
5 Mar 2019, 01:33
1.2
1 km West of Parzanica
21 km South-East · 11 km
7 years ago
12 Apr 2019, 11:13
1.2
2 km South-West of Bovegno
30 km East · 10 km
7 years ago
22 Feb 2019, 19:01

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).