All earthquakes
1.7
very light
EARTHQUAKE DETAILS

17 km East of Augusta

38 months ago · 25 Jul, 01:45

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

Stronger than 78% of Italian events in the past year

Where

17 km East of AugustaEarthquakes in the province of SiracusaEarthquakes in Sicilia

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.

5.4kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×89 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 ≈ 19 s

Animation sped up ~3× compared to reality.

  • Siracusa
    30 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Catania
    38 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 s
  • Acireale
    46 km from the epicentre
    first tremor in ~9 s
    main shaking in ~15 s
  • Modica
    60 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

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 (~17 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 2 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
1
last 7 days
3
last 30 days
3 before2 after
this quake
Strongest of the sequence1.7

How often does it happen here?

about every ~10 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 430 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.

16937.3
Sicilia sud-orientale earthquake
11 January 1693 · 34 km from here
XICatastrophic: very few buildings remain standing; landslides and ground cracks.
15426.7
Sicilia sud-orientale earthquake
10 December 1542 · 38 km from here
XCompletely destructive: most buildings are destroyed.
11696.5
Sicilia sud-orientale earthquake
4 February 1169 · 37 km from here
XCompletely destructive: most buildings are destroyed.
18186.3
Catanese earthquake
20 February 1818 · 44 km from here
IX-XCompletely destructive: most buildings are destroyed.

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

The closest seismic structure

Alfeo

The epicentre lies about 8 km from Alfeo, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.7between 6 and 20 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

1.7
20 km North-East of Siracusa
19 km South-East · 22 km
38 months ago
28 Jul, 03:36
1.2
2 km West of Priolo Gargallo
22 km South-West · 1 km
38 months ago
28 Jul, 08:43
1.4
1 km West of Priolo Gargallo
21 km South-West · 1 km
38 months ago
20 Jul, 09:36
1.6
2 km West of Priolo Gargallo
22 km South-West · 1 km
38 months ago
11 Jul, 13:10
1.4
17 km East of Augusta
6 km North · 25 km
38 months ago
7 Jul, 05:06

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