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2.3
light
EARTHQUAKE DETAILS

M2.3 earthquake · 3 km North of Traversetolo (PR)

5 years ago · 13 May 2021, 03:18

A light earthquake, rarely felt by people. At this depth the shaking is felt, but rarely causes damage.

Stronger than 93% of Italian events in the past year

Where

3 km North of TraversetoloEarthquakes in the province of ParmaEarthquakes in Emilia-Romagna

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

3 events
Magnitude:lightweakmoderatestrong

The energy released

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

43kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×11 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 ≈ 15 s

Animation sped up ~3× compared to reality.

  • Parma
    14 km from the epicentre
    first tremor in ~5 s
    main shaking in ~9 s
  • Reggio nell'Emilia
    21 km from the epicentre
    first tremor in ~6 s
    main shaking in ~10 s
  • Modena
    43 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Carpi
    46 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 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

27 km
medium depth
3 times the height of Mount Everest

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

deeper than the area average (~18 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 (M2.7, 5 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.7
The mainshock
3 km North-West of Traversetolo
5 years ago · 13 May 2021, 03:04
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
5
last 30 days
2 before0 after
this quake
Strongest of the sequence2.7

How often does it happen here?

about every ~4 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 1022 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.

15016.0
Modenese earthquake
5 June 1501 · 42 km from here
IXDestructive: many buildings partly or fully collapse.
18346.0
Val di Taro-Lunigiana earthquake
14 February 1834 · 47 km from here
IXDestructive: many buildings partly or fully collapse.
19205.6
Garfagnana earthquake
6 September 1920 · 46 km from here
14815.6
Lunigiana earthquake
7 May 1481 · 47 km from here
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

Langhirano-Sassuolo

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

estimated maximum magnitude 6.8between 2 and 8 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

2.0
2 km North-West of Traversetolo
1 km South-West · 25 km
5 years ago
13 May 2021, 03:07
2.7
3 km North-West of Traversetolo
1 km South-West · 24 km
5 years ago
13 May 2021, 03:04

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).