All earthquakes
2.2
light
EARTHQUAKE DETAILS

M2.2 earthquake · 13 km North-East of Porto Sant'Elpidio (FM)

8 years ago · 13 Jan 2018, 05:49

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

Stronger than 92% of Italian events in the past year

Where

13 km North-East of Porto Sant'ElpidioEarthquakes in the province of FermoEarthquakes in Marche

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.

30kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×16 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 ≈ 27 s

Animation sped up ~5× compared to reality.

  • Ancona
    43 km from the epicentre
    first tremor in ~7 s
    main shaking in ~13 s
  • Teramo
    75 km from the epicentre
    first tremor in ~13 s
    main shaking in ~21 s
  • Fano
    90 km from the epicentre
    first tremor in ~15 s
    main shaking in ~26 s
  • Foligno
    95 km from the epicentre
    first tremor in ~16 s
    main shaking in ~27 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 (~22 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 5 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 before5 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~12 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 373 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.

19435.7
Ascolano earthquake
3 October 1943 · 47 km from here
IXDestructive: many buildings partly or fully collapse.
16905.6
Costa anconetana earthquake
23 December 1690 · 34 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
12695.6
Costa anconetana earthquake
September 1269 · 37 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
19175.2
Costa anconetana earthquake
5 November 1917 · 35 km from here
VI-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

Conrad

The epicentre lies about 2 km from Conrad, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 5.9between 2 and 7 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 Monterubbiano
29 km South-West · 21 km
8 years ago
16 Jan 2018, 21:40
1.6
3 km East of Fermo
27 km South-West · 22 km
8 years ago
17 Jan 2018, 05:05
1.6
2 km North-East of Ponzano di Fermo
28 km South-West · 21 km
8 years ago
17 Jan 2018, 09:31
2.1
2 km North-West of Ponzano di Fermo
29 km South-West · 28 km
8 years ago
18 Jan 2018, 14:44
1.9
3 km East of Ponzano di Fermo
29 km South-West · 20 km
8 years ago
21 Jan 2018, 08:24

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).