Information message about the devastating earthquake in Central Italy, October 30, 2016 |
| The devastating earthquake M=6.7 has occurred on October 30, 2016 at 06:40 GMT (09:40 Moscow time) in Central Italy. |
| Parameters of the earthquake
have been determined in the Alert Service (AS) of Information
Processing Center (IPC) of Geophysical Survey of RAS in Obninsk with station data
obtained from digital and analog seismic stations of Russia, countries of CIS
and from abroad. Alert message on this earthquake has been delivered in 11 min after
registration to the Ministry of Emergency of the Russian Federation (EMERCOM). |
| Preliminary processing has been done with data from 34 stations, accurate processing - with data 80 stations. |
| Fig. 1 presents fragments of records obtained from digital stations Apeiranthos of Naxos (∆ 11.1º), Malin Array (∆ 13.6º), Isparta (∆ 14.2º), Keshkin SH Array (∆ 15.7º), Kongsberg (∆ 17º). Fig. 2 presents fragments of records obtained from digital stations Vasula (∆ 17.8º), Sochi (∆ 19.4º), Obninsk (∆ 19.6º), Kislovodsk (∆ 21.5º), Khabaz (∆ 21.7º). |
Figure 1
| 
Figure 2
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|
| IPC GS RAS also has obtained information with parameters of this event from some seismological centers, these data are given in table 1: |
| Table 1 |
| NN |
Time in origin h-min-s (GMT) |
Lat degr. |
Lon degr. |
Depth km |
N s/st |
Ms/ N |
mb/ N |
I0 calc |
GAP |
Center | | 1 |
06-40-17.2 |
42.8 |
13.12 |
10 |
80 |
6.7/43 | 6.6/36 | 9.5 | 76 | IPC GS RAS (Accurate) | | 2 |
06-40-24.4 |
42.89 |
13.41 |
33 |
34 |
| 6.3/10 | 6.5 -7 | | IPC GS RAS (Preliminary) | | 3 |
06-40-18.3 |
42.84 |
13.11 |
10 |
168 |
Mw 6.5 | | | 27 | CSEM | | 4 |
06-40-19.2 |
42.86 |
13.09 |
10 |
124 |
Mw 6.6 | | | 28 | NEIC | |
| IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences |
| CSEM - European - Mediterranean seismological center |
| NEIC - National Earthquakes Information Center of US Geological Service |
| Epicenter |
| Fig. 3 presents with red star the epicenter of this earthquake, its origin was located in the central part of Italy at the depth of 10 km, 54 km N-N-W of L'Aquila, 70 km E-S-E of Perugia and 113 km N-E of Rome.
|
Figure 3 |
|
| Aftershock |
| GS RAS registered 9 aftershocks М>=4.4 within one day after the main shock. |
| N |
Date & Time (GMT)
yy-mm-dd hh:mm:sec |
Lat
degr. |
Lon
degr. |
Depth
km |
N
station |
Ms/ N |
mb/ N |
Io
calc. |
Region |
| 20163852 | 2016-10-30 07:13:05.0 | 42.71 | 13.29 | 10 | 21 | - | 4.6/ 12 | 4.5 | Central Italy | | 20163853 | 2016-10-30 07:34:47.0 | 42.92 | 12.97 | 10 | 10 | - | 4.4/ 7 | 4 | Central Italy | | 20163854 | 2016-10-30 08:35:59.0 | 42.82 | 13.14 | 10 | 22 | - | 4.8/ 12 | 4.5-5 | Central Italy | | 20163858 | 2016-10-30 12:07:01.0 | 42.85 | 13.1 | 10 | 27 | - | 5.0/ 16 | 5-5.5 | Central Italy | | 20163859 | 2016-10-30 13:34:54.0 | 42.93 | 12.9 | 10 | 23 | - | 4.7/ 12 | 4.5-5 | Central Italy | | 20163860 | 2016-10-30 14:03:19.0 | 43.07 | 13.38 | 10 | 16 | - | 4.5/ 10 | 4-4.5 | Central Italy | | 20163863 | 2016-10-30 18:21:10.0 | 42.93 | 13.07 | 10 | 22 | - | 4.5/ 11 | 4-4.5 | Central Italy | | 20163867 | 2016-10-31 03:27:39.0 | 42.85 | 12.89 | 10 | 23 | - | 4.6/ 13 | 4.5 | Central Italy | | 20163870 | 2016-10-31 07:05:43.0 | 42.75 | 13.2 | 10 | 22 | - | 4.6/ 12 | 4.5 | Central Italy | |
| Macroseismic manifestations |
| According to ITAR-TASS, several dozen people were injured in the earthquake. The number of homeless may reach 100 thousand. More than 40 settlements partially or completely were destroyed in the province of Macerata after the earthquake. Among the largest cities affected by the earthquake, Norcia (reg. Umbria), it hit a few, including ancient churches, among them the church of St. Benedict with a nunnery (Fig. 4). Undeground shocks were felt across the Italy.
Fig. 5 was obtained from USGS NEIC , it presents USGS Community Internet Intensity Map based on 1062 responses in 351 cities. |
Figure 4 | 
Figure 5 |
|
| Historical records |
| The epicenter was located 14 km S-S-W of the devastating earthquake's epicenter of October 26, 2016 М=6.2 and 13 km W-N-W of devastating earthquake's epicenter of August 24, 2016 М=6.2, which killed 297 persons. |
| Focal mechanism and seismic moment of the earthquake |
| Focal mechanism solution of the origin was obtained in IPC GS RAS with signs of initial arrivals of P waves at 71 stations, including 17 stations which registered compression waves (plus signs) and 54 stations which registered tensile waves (minus signs). These stations are located in the interval of epicentral distances of 2.4–99.6º and azimuthal sector Az=3-352º. Focal mechanism solution in stereographical projection at the lower hemisphere is shown at fig. 6, it's elements are given in table 2. Fig. 7, 8 present focal mechanism solutions obtained in USGS NEIC with W-phase Moment Tensor (Mww) technique and in Lamont-Doherty Earth Observatory Global CMT Columbia University, USA (LDEO GCMT) with СМТ (Centroid moment tensor) technique. All solutions are close. The earthquake has occurred under the action of tensile stresses oriented to the north–east. NP1 plane according to GS RAS has a circum-meridian direction of propagation, according to NEIC and GCMT - it strikes south-east, NP2 plane in all solutions strikes north-west. NP1 plane is more flat, the angle of dipping to the horizon DP=27-39º, NP2 palne is dipping to the horizon under the angle DP=53-63º. The type of motion along both planes – fault (according to GS RAS - with insignificant latteral component).
Seismic moment of this earthquake was obtained in IPC GS RAS with spectra of P waves registered at "Arti" station (∆ 31.81º), it makes Mo=1.2*10**19 N*m, Mw=6.7. According to USGS NEIC – Mo=1.071*10**19 N*m, Mw=6.6; according to LDEO GCMT – Mo=1.03*10**19 N*m, Mw=6.6
|
| Table 2 |
| Axes of main strengths |
Nodal planes |
Center |
| T |
P |
N |
NP1 |
NP2 |
| Pl |
Azm |
Pl |
Azm |
Pl |
Azm |
Stk |
Dp |
Slip |
Stk |
Dp |
Slip |
| 12 | 74 | 63 | 187 |
24 | 338 | 191 | 39 | -50 | 324 |
61 | -118 | IPC GS RAS | | 18 | 67 | 72 | 238 |
3 | 336 | 162 | 27 | -84 | 335 |
63 | -93 | NEIC | | 8 | 68 | 79 | 293 |
8 | 159 | 149 | 38 | -102 | 345 |
53 | -81 | GCMT | |
| IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences |
| NEIC - National Earthquakes Information Center of US Geological Service |
| GCMT - Lamont-Doherty Earth Observatory Global CMT Columbia University, USA |
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