Earthquake with magnitude of ML 1.1 on date 23-09-2021 and time 21:24:44 (UTC) in region 2 km N Norcia (PG)

A magnitude ML 1.1 earthquake occured in region: 2 km N Norcia (PG), on

  • 23-09-2021 21:24:44 (UTC)
  • 23-09-2021 23:24:44 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.814, 13.098 at 10 km depth.

The earthquake was located by: Sala Sismica INGV-Roma.

Search earthquakes: Any within 30 km radius

The values of hypocentral coordinates and magnitude may be revised at a later time as more information becomes available.

Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Norcia PG 2 4957 4957
Preci PG 9 724 5681
Castelsantangelo sul Nera MC 10 281 5962
Cascia PG 13 3217 9179
Visso MC 13 1107 10286
Cerreto di Spoleto PG 15 1075 11361
Ussita MC 15 444 11805
Sellano PG 16 1079 12884
Arquata del Tronto AP 17 1178 14062
Poggiodomo PG 17 117 14179
Accumoli RI 18 667 14846
Montegallo AP 20 523 15369
Vallo di Nera PG 20 364 15733

Municipalities with at least 50000 inhabitants

An earthquake occurred to
36 Km E of Foligno (57155 inhabitants)
46 Km NE of Terni (111501 inhabitants)
53 Km W of Teramo (54892 inhabitants)
57 Km NW of L'Aquila (69753 inhabitants)
66 Km SE of Perugia (166134 inhabitants)
92 Km E of Viterbo (67173 inhabitants)
92 Km W of Montesilvano (53738 inhabitants)
95 Km NE of Guidonia Montecelio (88673 inhabitants)
96 Km SW of Ancona (100861 inhabitants)
98 Km N of Tivoli (56533 inhabitants)
99 Km W of Pescara (121014 inhabitants)
Recent and historical seismicity
Seismic hazard
Shakemap
Felt maps
Preliminary map of the earthquake effects from the web questionnaire

Preliminary map of the earthquake effects from the web questionnaire

This map shows the distribution of earthquake resentment in the area, expressed in terms of intensity on the MCS scale (Mercalli-Cancani-Sieberg). Intensities are determined using data from questionnaires collected on the website http://www.hsit.it. The intensities shown are determined considering all the reports received from each municipality, and are all the more reliable the greater the number of questionnaires. The collected data are subjected to an automatic statistical filter, but are not checked individually. In particular, intensities greater than or equal to the VI degree of the MCS or EMS scale require on-site verification by specialized personnel. The black star is the epicenter of the earthquake that occurred. This map is updated every time citizens fill out new questionnaires. The number of questionnaires processed to obtain this map, the date and time of the last update are shown at the top right.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
ML 1.1 2021-09-23
21:24:44
42.814 13.0978 11 2021-09-23
21:35:51
Sala Sismica INGV-Roma 95798831
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-23 21:24:44 ± 0.05
Latitude 42.8140 ± 0.0027
Longitude 13.0978 ± 0.0049
Depth (km) 11 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 95798831

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 358
Semi-minor axis of confidence ellipse (meter) 229
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 104
Circular confidence region, given by single value of horizontal uncertainty (meter) 360
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 93
Number of associated phases, regardless of their use for origin computation 20
Number of defining phases 20
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.17
Epicentral distance of station closest to the epicenter (degree) 0.02338
Epicentral distance of station farthest from the epicenter (degree) 0.28868
Number of stations at which the event was observed 10
Number of stations from which data was used for origin computation 10
Magnitude information

ML:1.1

Field Value
Value 1.1
Uncertainty 0.3
Num. used stations 5
Type of magnitude ML
Reference to an origin 95798831
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-09-23 21:35:51
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.CSP1.EHZ. 2021-09-23T21:24:55.89 0.1 undecidable manual S 16 0.2887 50 0.03 96
IV.SMA1.EHZ. 2021-09-23T21:24:54.55 0.6 undecidable manual S 136 0.2527 50 -0.27 46
IV.T1299.EHE. 2021-09-23T21:24:54.11 0.1 undecidable manual S 143 0.2248 50 0.13 96
IV.CESI.HHZ. 2021-09-23T21:24:54.29 0.1 undecidable manual S 324 0.2374 50 -0.06 97
IV.FDMO.HHZ. 2021-09-23T21:24:53.81 0.3 undecidable manual S 358 0.2221 50 -0.1 72
IV.LNSS.HNN. 2021-09-23T21:24:53.53 0.3 undecidable manual S 191 0.2149 50 -0.16 71
IV.GAVE.HNE. 2021-09-23T21:24:52.94 0.1 undecidable manual S 231 0.1925 116 -0.04 98
IV.MMO1.HNZ. 2021-09-23T21:24:52.48 0.1 undecidable manual S 63 0.188 117 -0.35 92
IV.CSP1.EHZ. 2021-09-23T21:24:51.30 1.0 undecidable manual P 16 0.2887 50 0.14 24
IV.MC2.EHE. 2021-09-23T21:24:50.38 0.1 undecidable manual S 34 0.1178 129 -0.15 97
IV.CESI.HHZ. 2021-09-23T21:24:50.32 0.3 positive manual P 324 0.2374 50 0.04 73
IV.SMA1.EHZ. 2021-09-23T21:24:50.45 1.0 undecidable manual P 136 0.2527 50 -0.09 24
IV.T1299.EHE. 2021-09-23T21:24:50.16 0.1 undecidable manual P 143 0.2248 50 0.09 96
IV.FDMO.HHZ. 2021-09-23T21:24:50.03 1.0 negative manual P 358 0.2221 50 0.01 25
IV.LNSS.HNN. 2021-09-23T21:24:49.93 0.1 undecidable manual P 191 0.2149 50 0.03 98
IV.GAVE.HNE. 2021-09-23T21:24:49.31 0.6 undecidable manual P 231 0.1925 116 -0.18 48
IV.MMO1.HNZ. 2021-09-23T21:24:49.80 0.3 undecidable manual P 63 0.188 117 0.4 68
IV.NRCA.HHZ. 2021-09-23T21:24:48.35 0.1 undecidable manual S 32 0.0234 166 -0.1 100
IV.MC2.EHE. 2021-09-23T21:24:48.38 0.1 undecidable manual P 34 0.1178 129 0.31 94
IV.NRCA.HHZ. 2021-09-23T21:24:47.07 0.1 undecidable manual P 32 0.0234 166 0.2 98
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.NRCA.HHE. ML:1 0.00019116475 0.0768 AML other m 2021-09-23T21:24:48.40
IV.NRCA.HHN. ML:1.3 0.00037772495 0.1408 AML other m 2021-09-23T21:24:48.45
IV.NRCA.HNE. ML:1 0.00019172115 0.0896 AML other m 2021-09-23T21:24:48.40
IV.NRCA.HNN. ML:1.3 0.00033273795 0.1408 AML other m 2021-09-23T21:24:48.47
IV.FDMO.HHE. ML:0.2 7.9503145E-6 0.1664 AML other m 2021-09-23T21:24:54.47
IV.FDMO.HHN. ML:-0.1 6.7726685E-6 0.1408 AML other m 2021-09-23T21:24:55.16
IV.CESI.HHE. ML:0 6.797041E-6 0.2176 AML other m 2021-09-23T21:24:54.73
IV.SMA1.EHN. ML:0.5 1.6530505E-5 0.192 AML other m 2021-09-23T21:24:55.74
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download