Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 0.7 on date 21-10-2018 and time 19:43:27 (Italy) in region 4 km SW Arquata del Tronto (AP)

A magnitude ML 0.7 earthquake occured in region: 4 km SW Arquata del Tronto (AP), on

  • 21-10-2018 17:43:27 (UTC)
  • 21-10-2018 19:43:27 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.75, 13.26 at 9 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.

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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 4 1178 1178
Accumoli RI 6 667 1845
Montegallo AP 12 523 2368
Acquasanta Terme AP 13 2916 5284
Amatrice RI 14 2657 7941
Norcia PG 14 4957 12898
Cittareale RI 17 482 13380
Montemonaco AP 18 604 13984
Castelsantangelo sul Nera MC 18 281 14265
Valle Castellana TE 20 977 15242

Municipalities with at least 50000 inhabitants

An earthquake occurred to
38 Km W of Teramo (54892 inhabitants)
46 Km N of L'Aquila (69753 inhabitants)
51 Km E of Foligno (57155 inhabitants)
54 Km E of Terni (111501 inhabitants)
78 Km W of Montesilvano (53738 inhabitants)
81 Km E of Perugia (166134 inhabitants)
84 Km W of Pescara (121014 inhabitants)
87 Km NW of Chieti (51815 inhabitants)
94 Km NE of Guidonia Montecelio (88673 inhabitants)
95 Km NE of Tivoli (56533 inhabitants)
99 Km S of Ancona (100861 inhabitants)
Recent and historical Seismicity
Seismic hazard
Shakemap
Felt maps
The earthquake effects in MCS scale as obtained from the compiled questionnaire

The earthquake effects in MCS scale as obtained from the compiled questionnaire

This map shows the distribution of the effects of the earthquake on the territory in terms of the MCS (Mercalli-Cancani-Sieberg) intensity scale. The intensities are determined using the data provided in the questionnaire (http://www.haisentitoilterremoto.it/) that are analysed using robust statistical techniques since they are not verified individually. Specifically, the assignment of MCS intensities greater or equal the VI degree of the MCS scale require opportune in situ verification by professional experts. The purple start shows the epicenter. This map is prepared every so often that the population fill in new questionnaires. The number of questionnaires used to determine the map and the date and time of the last adjournment are shown in the upper right part of the panel.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Rev 100 ML 0.7 2018-10-21
17:43:27		 42.75 13.26 9 2018-10-21
17:53:58		 Sala Sismica INGV-Roma 62179911
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2018-10-21 17:43:27 ± 0.05
Latitude 42.75 ± 0.00
Longitude 13.26 ± 0.00
Depth (km) 9 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 62179911

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 320
Semi-minor axis of confidence ellipse (meter) 131
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 256
Circular confidence region, given by single value of horizontal uncertainty (meter) 320
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 54
Number of associated phases, regardless of their use for origin computation 22
Number of defining phases 22
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.19
Epicentral distance of station closest to the epicenter (degree) 0.10162
Epicentral distance of station farthest from the epicenter (degree) 0.34444
Number of stations at which the event was observed 13
Number of stations from which data was used for origin computation 13
Magnitude information

ML:0.7

Field Value
Value 0.7
Uncertainty 0.2
Num. used stations 4
Type of magnitude ML
Reference to an origin 62179911
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2018-10-21 17:53:58
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.CSP1.EHZ. 2018-10-21T17:43:40.58 0.3 undecidable manual S 353 0.3444 50 0.26 69
IV.TERO.HHZ. 2018-10-21T17:43:38.13 0.3 undecidable manual S 116 0.2833 50 -0.39 68
IV.RM33.HNZ. 2018-10-21T17:43:37.32 0.3 undecidable manual S 188 0.2428 109 0.19 71
IV.LNSS.HHZ. 2018-10-21T17:43:36.26 0.3 undecidable manual S 228 0.2167 111 0.05 73
IV.CAMP.HHZ. 2018-10-21T17:43:36.80 0.3 undecidable manual S 153 0.2401 109 -0.26 70
IV.CSP1.EHZ. 2018-10-21T17:43:34.72 0.1 undecidable manual P 353 0.3444 50 -0.08 95
IV.MMO1.EHZ. 2018-10-21T17:43:34.09 0.1 undecidable manual S 18 0.1583 118 -0.05 99
IV.FDMO.HHE. 2018-10-21T17:43:34.13 0.3 undecidable manual P 336 0.313 50 -0.13 71
IV.MF5.EHZ. 2018-10-21T17:43:34.03 0.3 undecidable manual P 32 0.2797 50 0.34 68
IV.TERO.HHZ. 2018-10-21T17:43:33.85 0.3 undecidable manual P 116 0.2833 50 0.1 72
IV.SMA1.EHZ. 2018-10-21T17:43:33.40 0.3 undecidable manual S 155 0.1313 122 0.14 73
IV.GAVE.HNZ. 2018-10-21T17:43:33.52 0.1 undecidable manual P 258 0.2734 50 -0.06 97
IV.RM33.HNZ. 2018-10-21T17:43:33.03 0.3 undecidable manual P 188 0.2428 109 0.07 73
IV.MTRA.EHZ. 2018-10-21T17:43:32.26 0.1 undecidable manual S 86 0.1016 129 -0.06 100
IV.NRCA.HNZ. 2018-10-21T17:43:32.99 0.3 undecidable manual S 309 0.1349 122 -0.38 70
IV.CAMP.HHZ. 2018-10-21T17:43:32.60 0.3 undecidable manual P 153 0.2401 109 -0.31 69
IV.LNSS.HHZ. 2018-10-21T17:43:32.40 0.3 undecidable manual P 228 0.2167 111 -0.03 74
IV.MC2.EHZ. 2018-10-21T17:43:31.51 0.3 undecidable manual P 343 0.17 116 0.05 74
IV.SMA1.EHZ. 2018-10-21T17:43:31.07 0.3 undecidable manual P 155 0.1313 122 0.35 70
IV.MMO1.EHZ. 2018-10-21T17:43:31.23 0.1 undecidable manual P 18 0.1583 118 0 100
IV.MTRA.EHZ. 2018-10-21T17:43:30.32 0.1 undecidable manual P 86 0.1016 129 0.14 98
IV.NRCA.HNZ. 2018-10-21T17:43:30.88 0.3 undecidable manual P 309 0.1349 122 0.09 74
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.MTRA.EHN. ML:0.6 4.668809E-5 0.0384 AML other m 2018-10-21T17:43:32.74
IV.SMA1.EHN. ML:0.5 3.2699285E-5 0.2048 AML other m 2018-10-21T17:43:33.51
IV.TERO.HHE. ML:0.6 2.06120755E-5 0.1536 AML other m 2018-10-21T17:43:38.25
IV.TERO.HHN. ML:0.9 3.9457425E-5 0.1024 AML other m 2018-10-21T17:43:38.46
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download