All earthquakes
2.1
light
EARTHQUAKE DETAILS

M2.1 earthquake · 1 km South-East of Vico del Gargano (FG)

10 years ago · 7 May 2016, 01:17

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

Stronger than 90% of Italian events in the past year

Where

1 km South-East of Vico del GarganoEarthquakes in the province of FoggiaEarthquakes in Puglia

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

11 events
Magnitude:lightweakmoderatestrong

The energy released

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

21kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×22 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 ≈ 20 s

Animation sped up ~4× compared to reality.

  • Manfredonia
    35 km from the epicentre
    first tremor in ~7 s
    main shaking in ~12 s
  • San Severo
    51 km from the epicentre
    first tremor in ~9 s
    main shaking in ~16 s
  • Foggia
    56 km from the epicentre
    first tremor in ~10 s
    main shaking in ~17 s
  • Barletta
    66 km from the epicentre
    first tremor in ~12 s
    main shaking in ~20 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

21 km
medium depth
2.3 times the height of Mount Everest

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

deeper than the area average (~15 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 (M2.8, 10 years ago) in the same area. Aftershocks are normal after an earthquake and tend to fade over time.

2.8
The mainshock
4 km North of Monte Sant'Angelo
10 years ago · 11 Apr 2016, 14:27
Activity in the area right now (30 km radius)
0
last 24 hours
0
last 7 days
2
last 30 days
7 before3 after
this quake
Strongest of the sequence2.8

How often does it happen here?

about every ~9 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 506 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.

16466.7
Gargano earthquake
31 May 1646 · 5 km from here
XCompletely destructive: most buildings are destroyed.
18755.9
Gargano earthquake
6 December 1875 · 32 km from here
VIIIRuinous: partial collapses in ordinary buildings, widespread heavy damage.
14145.8
Gargano earthquake
1414 · 16 km from here
VIII-IXDestructive: many buildings partly or fully collapse.
16475.7
Gargano earthquake
5 May 1647 · 39 km from here
VII-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

San Marco in Lamis-Mattinata

The epicentre lies about 14 km from San Marco in Lamis-Mattinata, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 7.0between 0 and 25 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
14 km South-East of Mattinata
30 km South-East · 17 km
10 years ago
3 May 2016, 11:27
2.4
13 km North-West of Rodi Garganico
23 km North-West · 4 km
10 years ago
2 May 2016, 18:58
1.2
9 km West of Monte Sant'Angelo
18 km South-West · 19 km
10 years ago
27 Apr 2016, 19:21
1.9
10 km South-West of Carpino
19 km South-West · 22 km
10 years ago
26 Apr 2016, 21:31
2.0
10 years ago
19 May 2016, 02:13
2.0
6 km West of Monte Sant'Angelo
14 km South-West · 22 km
10 years ago
24 May 2016, 19:02
0.9
4 km South of Carpino
12 km South-West · 25 km
10 years ago
18 Apr 2016, 11:58
1.6
10 years ago
18 Apr 2016, 11:44
2.8
10 years ago
11 Apr 2016, 14:27
1.5
17 km North of Rodi Garganico
25 km North-West · 10 km
10 years ago
5 Jun 2016, 23:15

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).