All earthquakes
1.6
very light
EARTHQUAKE DETAILS

M1.6 earthquake · 1 km South-East of Carassai (AP)

9 years ago · 22 Nov 2016, 01:12

A very light earthquake, probably not felt by people. Being deep, it is felt less at the surface.

Stronger than 74% of Italian events in the past year

Where

1 km South-East of CarassaiEarthquakes in the province of Ascoli PicenoEarthquakes 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

44 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 ≈ 22 s

Animation sped up ~4× compared to reality.

  • Teramo
    40 km from the epicentre
    first tremor in ~8 s
    main shaking in ~14 s
  • Ancona
    65 km from the epicentre
    first tremor in ~12 s
    main shaking in ~21 s
  • Montesilvano
    71 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 s
  • Foligno
    71 km from the epicentre
    first tremor in ~13 s
    main shaking in ~22 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

31 km
deep
3.5 times the height of Mount Everest

Being deep, it is felt less at the surface.

deeper than the area average (~11 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: 9 years ago the same area had a stronger quake (M2.9). This can only be said after the fact — it was not predictable beforehand.

2.9
The mainshock
2 km South of Montegranaro
9 years ago · 8 Dec 2016, 14:34
Activity in the area right now (30 km radius)
0
last 24 hours
3
last 7 days
19
last 30 days
20 before23 after
this quake
Strongest of the sequence2.9

How often does it happen here?

about every ~1 days

Within 50 km of this epicentre, a magnitude ≥ 2 earthquake has occurred on average this often: 7650 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.

17996.2
Appennino marchigiano earthquake
28 July 1799 · 47 km from here
IX-XCompletely destructive: most buildings are destroyed.
20166.1
Valnerina earthquake
26 October 2016 · 50 km from here
18735.8
Appennino marchigiano earthquake
12 March 1873 · 36 km from here
IXDestructive: many buildings partly or fully collapse.
19435.7
Ascolano earthquake
3 October 1943 · 10 km from here
IXDestructive: many buildings partly or fully collapse.

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

The closest seismic structure

Southern Marche

The epicentre lies about 1 km from Southern Marche, one of the seismic structures mapped by INGV geologists.

estimated maximum magnitude 6.9between 4 and 11 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

2.0
2 km South-West of Venarotta
21 km South-West · 19 km
9 years ago
22 Nov 2016, 03:13
1.6
1 km East of Venarotta
19 km South-West · 19 km
9 years ago
22 Nov 2016, 03:18
1.6
1 km East of Venarotta
19 km South-West · 19 km
9 years ago
22 Nov 2016, 03:29
2.0
1 km South-East of Venarotta
20 km South-West · 19 km
9 years ago
22 Nov 2016, 03:40
2.1
2 km South of Venarotta
21 km South-West · 19 km
9 years ago
22 Nov 2016, 04:34
1.8
2 km South of Venarotta
21 km South-West · 19 km
9 years ago
22 Nov 2016, 04:56
1.3
4 km North-West of Roccafluvione
28 km South-West · 17 km
9 years ago
25 Nov 2016, 06:26
2.6
4 km East of Montegallo
30 km South-West · 23 km
9 years ago
17 Nov 2016, 17:37
1.8
4 km North-West of Roccafluvione
29 km South-West · 26 km
9 years ago
17 Nov 2016, 08:59
1.5
9 years ago
28 Nov 2016, 09:16

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).