Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.7 on date 25-01-2021 and time 17:21:23 (UTC) in region 9 km NW Arquata del Tronto (AP)

A magnitude ML 1.7 earthquake occured in region: 9 km NW Arquata del Tronto (AP), on

  • 25-01-2021 17:21:23 (UTC)
  • 25-01-2021 18:21:23 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.8330, 13.2240 at 14 km depth.

The earthquake was located by: Bollettino Sismico Italiano INGV.

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.

Hai sentito il terremoto? Clicca qui

Did you feel it? Fill in the questionnaire.

Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Arquata del Tronto AP 9 1178 1178
Castelsantangelo sul Nera MC 9 281 1459
Montegallo AP 9 523 1982
Montemonaco AP 11 604 2586
Norcia PG 12 4957 7543
Ussita MC 14 444 7987
Accumoli RI 15 667 8654
Visso MC 16 1107 9761
Montefortino FM 16 1178 10939
Preci PG 16 724 11663
Acquasanta Terme AP 17 2916 14579
Bolognola MC 18 142 14721
Amandola FM 20 3629 18350

Municipalities with at least 50000 inhabitants

An earthquake occurred to
44 Km W of Teramo (54892 inhabitants)
45 Km E of Foligno (57155 inhabitants)
55 Km N of L'Aquila (69753 inhabitants)
56 Km NE of Terni (111501 inhabitants)
75 Km E of Perugia (166134 inhabitants)
84 Km W of Montesilvano (53738 inhabitants)
91 Km S of Ancona (100861 inhabitants)
91 Km W of Pescara (121014 inhabitants)
94 Km NW of Chieti (51815 inhabitants)
Recent and historical seismicity
Seismic hazard
Shakemap
Felt maps
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Bulletin
Rev1000 		ML 1.7 2021-01-25
17:21:23		 42.8327 13.2243 14 2021-07-12
16:54:59		 Bollettino Sismico Italiano INGV 87376091
Reviewed
Rev100 		ML 1.7 2021-01-25
17:21:23		 42.8367 13.2352 12 2021-01-25
17:29:36		 Sala Sismica INGV-Roma 86569521
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-01-25 17:21:23 ± 0.1
Latitude 42.8327 ± 0.0036
Longitude 13.2243 ± 0.0074
Depth (km) 14 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 87376091

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 546
Semi-minor axis of confidence ellipse (meter) 251
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 97
Circular confidence region, given by single value of horizontal uncertainty (meter) 550.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 79
Number of associated phases, regardless of their use for origin computation 15
Number of defining phases 14
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) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.34894
Number of stations at which the event was observed 9
Number of stations from which data was used for origin computation 8
Magnitudes information

ML:1.7

Field Value
Value 1.7
Uncertainty 0.1
Num. used stations 4
Type of magnitude ML
Reference to an origin 87376091
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-02-22 12:04:32

ML:1.7

Field Value
Value 1.7
Uncertainty 0.2
Num. used stations 6
Type of magnitude ML
Reference to an origin 86569521
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-01-25 17:29:36
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.T0110.HHZ. 2021-01-25T17:21:51.66 3.0 undecidable manual S 0.93 0
IV.GUMA.HNN. 2021-01-25T17:21:33.90 0.6 undecidable manual S 19 27.0507 100 0.68 55
IV.CSP1.EHZ. 2021-01-25T17:21:33.61 0.6 undecidable manual S 357 28.749 99 -0.07 64
IV.FDMO.HHN. 2021-01-25T17:21:32.67 0.6 undecidable manual S 334 25.2525 101 -0.06 65
IV.SMA1.EHZ. 2021-01-25T17:21:32.40 0.6 undecidable manual S 158 24.1536 102 -0.07 64
IV.TERO.HHZ. 2021-01-25T17:21:30.95 0.6 undecidable manual P 127 38.7279 95 0.06 63
IV.CSP1.EHZ. 2021-01-25T17:21:29.30 0.6 undecidable manual P 357 28.749 99 -0.07 64
IV.GUMA.HNN. 2021-01-25T17:21:29.19 0.6 undecidable manual P 19 27.0507 100 0.09 64
IV.LNSS.HNZ. 2021-01-25T17:21:29.58 0.6 undecidable manual P 211 29.5482 98 0.09 64
IV.SMA1.EHZ. 2021-01-25T17:21:28.62 0.6 undecidable manual P 158 24.1536 102 -0.05 65
IV.NRCA.HHZ. 2021-01-25T17:21:28.89 0.6 undecidable manual S 271 8.9799 138 0.03 66
IV.MMO1.EHZ. 2021-01-25T17:21:28.97 0.3 undecidable manual S 48 11.1777 129 -0.32 95
IV.FDMO.HHN. 2021-01-25T17:21:28.64 0.6 undecidable manual P 334 25.2525 101 -0.18 63
IV.NRCA.HHZ. 2021-01-25T17:21:26.73 0.3 undecidable manual P 271 8.9799 138 0.14 98
IV.MMO1.EHZ. 2021-01-25T17:21:26.80 0.3 undecidable manual P 48 11.1777 129 -0.03 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.NRCA.HNE. ML:1.7 0.000533 1.82 AML other m 2021-01-25T17:21:29.95
IV.NRCA.HHE. ML:1.7 0.0005265 1.82 AML other m 2021-01-25T17:21:29.95
IV.NRCA.HNN. ML:1.8 0.0007155 0.14 AML other m 2021-01-25T17:21:29.07
IV.NRCA.HHN. ML:1.8 0.0007455000000000001 0.16 AML other m 2021-01-25T17:21:29.08
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