All earthquakes
2.9
light
EARTHQUAKE DETAILS

M2.9 earthquake · 5 km South-East of Borgo Val di Taro (PR)

7 years ago · 21 Mar 2019, 22:42

A light earthquake, rarely felt by people. At only a few km deep the shaking is felt more sharply at the surface.

Stronger than 98% of Italian events in the past year

Where

5 km South-East of Borgo Val di TaroEarthquakes in the province of ParmaEarthquakes in Emilia-Romagna

How far away could it be felt?

An estimate of how far people may have felt this quake.

  • up to ~8 km · felt only by some, at rest
    ≈ 7,000 people live in this area

The coloured rings on the map below show these distances.

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

12 events
Magnitude:lightweakmoderatestrong

The energy released

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

338kgof TNT equivalent
1.4 lightning bolts
M3
A magnitude 3 earthquake releases ×1.4 its energy
M2this quakeM4

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 ≈ 16 s

Animation sped up ~3× compared to reality.

  • La Spezia
    41 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • Carrara
    48 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Massa
    54 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Parma
    54 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 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.

shallower than the area average (~16 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?

Mainshock

It is the strongest quake of its sequence: so far it has been followed by 11 aftershocks within 30 km. Aftershocks tend to fade in number and strength over time.

Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
2
last 30 days
0 before11 after
this quake
Strongest of the sequence2.6

How often does it happen here?

about every ~14 days

Within 50 km of this epicentre, a magnitude ≥ 2.5 earthquake has occurred on average this often: 304 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.

19206.5
Garfagnana earthquake
7 September 1920 · 48 km from here
XCompletely destructive: most buildings are destroyed.
18346.0
Val di Taro-Lunigiana earthquake
14 February 1834 · 5 km from here
IXDestructive: many buildings partly or fully collapse.
18375.9
Lunigiana earthquake
11 April 1837 · 44 km from here
XCompletely destructive: most buildings are destroyed.
19205.6
Garfagnana earthquake
6 September 1920 · 44 km from here

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

The closest seismic structure

Lunigiana

The epicentre sits above this source area: the deep structure where this area's earthquakes can originate.

estimated maximum magnitude 7.0between 1 and 10 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
7 years ago
22 Mar 2019, 05:55
1.3
7 years ago
25 Mar 2019, 11:17
0.5
5 km South-West of Licciana Nardi
29 km South-East · 11 km
7 years ago
30 Mar 2019, 09:43
1.2
7 years ago
30 Mar 2019, 13:59
1.6
4 km South-West of Terenzo
22 km North-East · 28 km
7 years ago
31 Mar 2019, 18:05
1.8
4 km West of Terenzo
23 km North-East · 30 km
7 years ago
31 Mar 2019, 18:17
1.8
4 km North of Compiano
14 km North-West · 8 km
7 years ago
17 Apr 2019, 08:05
1.4
5 km North of Compiano
16 km North-West · 11 km
7 years ago
17 Apr 2019, 16:30
1.6
4 km North of Compiano
16 km North-West · 7 km
7 years ago
20 Apr 2019, 04:08
2.0
5 km North of Varsi
24 km North · 29 km
7 years ago
20 Apr 2019, 16:27

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).