All earthquakes
1.2
very light
EARTHQUAKE DETAILS

M1.2 earthquake · 5 km South of San Nicandro Garganico (FG)

7 years ago · 23 Aug 2019, 10:53

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

Stronger than 48% of Italian events in the past year

Where

5 km South of San Nicandro GarganicoEarthquakes 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

21 events
Magnitude:lightweakmoderatestrong

The energy released

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

1.0kgof TNT equivalent
Less than the energy of a lightning bolt
M3
A magnitude 3 earthquake releases ×501 its energy
M0this quakeM2

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 ~4× compared to reality.

  • San Severo
    23 km from the epicentre
    first tremor in ~5 s
    main shaking in ~9 s
  • Manfredonia
    31 km from the epicentre
    first tremor in ~7 s
    main shaking in ~11 s
  • Foggia
    38 km from the epicentre
    first tremor in ~7 s
    main shaking in ~13 s
  • Cerignola
    64 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

23 km
medium depth
2.6 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?

Foreshock

In hindsight it was a foreshock: 7 years ago the same area had a stronger quake (M2.6). This can only be said after the fact — it was not predictable beforehand.

2.6
The mainshock
6 km West of San Marco in Lamis
7 years ago · 24 Aug 2019, 14:30
Activity in the area right now (30 km radius)
0
last 24 hours
2
last 7 days
11
last 30 days
8 before12 after
this quake
Strongest of the sequence2.6

How often does it happen here?

about every ~8 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 560 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 · 37 km from here
XCompletely destructive: most buildings are destroyed.
16276.7
Capitanata earthquake
30 July 1627 · 20 km from here
XCompletely destructive: most buildings are destroyed.
16276.0
Capitanata earthquake
7 August 1627 · 21 km from here
IXDestructive: many buildings partly or fully collapse.
16576.0
Capitanata earthquake
29 January 1657 · 17 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

San Marco in Lamis-Mattinata

The epicentre lies about 6 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

1.2
7 years ago
22 Aug 2019, 10:06
2.6
7 years ago
24 Aug 2019, 14:30
1.8
7 years ago
25 Aug 2019, 22:29
1.6
6 km North-West of Lesina
23 km North-West · 9 km
7 years ago
20 Aug 2019, 11:23
1.0
7 years ago
27 Aug 2019, 10:29
1.2
2 km North of San Giovanni Rotondo
23 km South-East · 17 km
7 years ago
17 Aug 2019, 16:15
0.8
9 km East of Rignano Garganico
13 km South-East · 18 km
7 years ago
30 Aug 2019, 06:24
1.7
7 years ago
1 Sept 2019, 00:27
1.6
6 km North-West of Cagnano Varano
13 km North-East · 25 km
7 years ago
2 Sept 2019, 23:22
1.8
15 km North-West of Rodi Garganico
26 km North-East · 22 km
7 years ago
3 Sept 2019, 02:52

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).