All earthquakes
1.6
very light
EARTHQUAKE DETAILS

M1.6 earthquake · 5 km West of San Costanzo (PU)

11 years ago · 24 Jan 2015, 01:20

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

Stronger than 74% of Italian events in the past year

Where

5 km West of San CostanzoEarthquakes in the province of Pesaro e UrbinoEarthquakes 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

10 events
Magnitude:lightweakmoderatestrong

The energy released

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

3.8kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×126 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.

  • Fano
    7 km from the epicentre
    first tremor in ~3 s
    main shaking in ~6 s
  • Pesaro
    18 km from the epicentre
    first tremor in ~4 s
    main shaking in ~7 s
  • Ancona
    43 km from the epicentre
    first tremor in ~8 s
    main shaking in ~13 s
  • Rimini
    50 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

19 km
medium depth
2.1 times the height of Mount Everest

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

deeper than the area average (~12 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?

Foreshock

In hindsight it was a foreshock: 11 years ago the same area had a stronger quake (M2.1). This can only be said after the fact — it was not predictable beforehand.

2.1
The mainshock
2 km South-West of Terre Roveresche
11 years ago · 7 Feb 2015, 00:27
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
7
last 30 days
2 before7 after
this quake
Strongest of the sequence2.1

How often does it happen here?

about every ~5 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 811 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.

17816.5
Cagliese earthquake
3 June 1781 · 42 km from here
XCompletely destructive: most buildings are destroyed.
17416.2
Fabrianese earthquake
24 April 1741 · 35 km from here
IXDestructive: many buildings partly or fully collapse.
19305.8
Senigallia earthquake
30 October 1930 · 32 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
19165.8
Riminese earthquake
17 May 1916 · 46 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

Pesaro-Senigallia

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

estimated maximum magnitude 6.3between 3 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

1.2
1 km South of Corinaldo
13 km South-East · 9 km
11 years ago
1 Feb 2015, 11:27
1.1
11 years ago
15 Jan 2015, 07:23
1.8
2 km South of Belvedere Ostrense
25 km South-East · 35 km
11 years ago
1 Feb 2015, 21:45
2.1
2 km South-West of Terre Roveresche
7 km South-West · 35 km
11 years ago
7 Feb 2015, 00:27
1.8
11 years ago
9 Feb 2015, 05:02
1.4
5 km South-East of Mondaino
25 km West · 22 km
11 years ago
7 Jan 2015, 04:55
1.7
4 km West of Sant'Ippolito
14 km West · 42 km
11 years ago
16 Feb 2015, 03:46
1.2
11 years ago
17 Feb 2015, 19:59
1.8
11 years ago
18 Feb 2015, 02:15

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).