All earthquakes
3.7
weak
EARTHQUAKE DETAILS

2 km North-West of Bagnolo in Piano

98 months ago · 21 Aug, 02:33

A weak earthquake, felt by some of the population. At only a few km deep the shaking is felt more sharply at the surface.

No. 6 of the month in ItalyStronger than 99% of Italian events in the past yearNo. 3 of the year in Emilia-RomagnaThe strongest of the past 12 months within 50 km

Where

2 km North-West of Bagnolo in PianoEarthquakes in the province of Reggio EmiliaEarthquakes in Emilia-Romagna

How far away could it be felt?

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

  • up to ~10 km · felt by many people, especially on upper floors
    ≈ 67,000 people live in this area
  • up to ~31 km · felt only by some, at rest
    ≈ 1.2m 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

3 events
Magnitude:lightweakmoderatestrong

The energy released

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

5.4tof TNT equivalent
22 lightning bolts
M3
×11 the energy of a magnitude 3 earthquake
M3this quakeM5

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 ≈ 8 s

Animation sped up ~1× compared to reality.

  • Reggio nell'Emilia
    12 km from the epicentre
    first tremor in ~2 s
    main shaking in ~4 s
  • Carpi
    19 km from the epicentre
    first tremor in ~4 s
    main shaking in ~6 s
  • Modena
    21 km from the epicentre
    first tremor in ~4 s
    main shaking in ~6 s
  • Parma
    26 km from the epicentre
    first tremor in ~5 s
    main shaking in ~8 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 (~20 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 one aftershock 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
0
last 7 days
0
last 30 days
1 before1 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~8 months

Within 50 km of this epicentre, a magnitude ≥ 3.5 earthquake has occurred on average this often: 17 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.

20126.1
Pianura emiliana earthquake
20 May 2012 · 49 km from here
VIIVery strong: hard to stand; chimneys and roof tiles fall, serious damage to weaker buildings.
15016.0
Modenese earthquake
5 June 1501 · 34 km from here
IXDestructive: many buildings partly or fully collapse.
20125.9
Pianura emiliana earthquake
29 May 2012 · 32 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
14385.6
Parmense earthquake
11 June 1438 · 34 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

Campegine-Correggio

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

estimated maximum magnitude 6.6between 3 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

2.1
2 km West of Bagnolo in Piano
1 km South-West · 5 km
98 months ago
21 Aug, 03:07
2.0
2 km West of Rio Saliceto
9 km East · 32 km
99 months ago
22 Jul, 06:16

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).

We use cookies to analyse site traffic and improve your experience.

Privacy PolicyCookie Policy