Earthquake with magnitude of Md 2.4 on date 21-07-1987 and time 17:58:00 (Italy) in region 5 km SW Acquasanta Terme (AP)

A magnitude Md 2.4 earthquake occured in region: 5 km SW Acquasanta Terme (AP), on

  • 21-07-1987 15:58:00 (UTC)
  • 21-07-1987 17:58:00 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.7290, 13.3860 at 10 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.

Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Acquasanta Terme AP 5 2916 2916
Arquata del Tronto AP 9 1178 4094
Valle Castellana TE 9 977 5071
Accumoli RI 12 667 5738
Rocca Santa Maria TE 13 537 6275
Montegallo AP 13 523 6798
Amatrice RI 14 2657 9455
Cortino TE 16 656 10111
Roccafluvione AP 17 2010 12121
Campotosto AQ 19 542 12663
Venarotta AP 19 2066 14729
Montemonaco AP 20 604 15333
Palmiano AP 20 196 15529

Municipalities with at least 50000 inhabitants

An earthquake occurred to
27 Km W of Teramo (54892 inhabitants)
42 Km N of L'Aquila (69753 inhabitants)
61 Km E of Foligno (57155 inhabitants)
63 Km E of Terni (111501 inhabitants)
67 Km W of Montesilvano (53738 inhabitants)
74 Km W of Pescara (121014 inhabitants)
77 Km NW of Chieti (51815 inhabitants)
91 Km E of Perugia (166134 inhabitants)
97 Km NE of Guidonia Montecelio (88673 inhabitants)
98 Km NE of Tivoli (56533 inhabitants)
99 Km S of Ancona (100861 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
Md 2.4
ML-VAX 1.7
1987-07-21
15:58:00
42.729 13.386 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 52629
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-07-21 15:58:00 ± 0.121
Latitude 42.7290 ± 0.0070
Longitude 13.3860 ± 0.0106
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 52629

Uncertainty

Field Value
Preferred uncertainty description horizontal uncertainty
Semi-major axis of confidence ellipse (meter)
Semi-minor axis of confidence ellipse (meter)
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi)
Circular confidence region, given by single value of horizontal uncertainty (meter) 1164.6
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 109
Number of associated phases, regardless of their use for origin computation 14
Number of defining phases 14
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.3
Epicentral distance of station closest to the epicenter (degree) 0.00121
Epicentral distance of station farthest from the epicenter (degree) 0.00745
Number of stations at which the event was observed 7
Number of stations from which data was used for origin computation 7
Magnitudes information

Md:2.4

Field Value
Value 2.4
Uncertainty
Num. used stations 4
Type of magnitude Md
Reference to an origin 52629
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:50:49

ML:1.7

Field Value
Value 1.7
Uncertainty
Num. used stations 2
Type of magnitude ML
Reference to an origin 52629
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2015-04-28 13:07:13
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.AM8.Z. 1987-07-21T15:58:30.27 10.0 undecidable manual SG 10 0.8214 0.93 0.1
--.ARV.Z. 1987-07-21T15:58:29.43 10.0 undecidable manual SG 337 0.8214 0.1 0.5
--.ASS.Z. 1987-07-21T15:58:23.48 10.0 undecidable manual SG 302 0.6327 0.64 0.2
--.MNS.Z. 1987-07-21T15:58:23.00 10.0 undecidable manual SG 236 0.6216 0.48 0.3
--.CM8.Z. 1987-07-21T15:58:18.75 10.0 undecidable manual SG 339 0.4995 0.21 0.9
--.AM8.Z. 1987-07-21T15:58:17.20 10.0 undecidable manual PG 10 0.8214 0 1.4
--.ARV.Z. 1987-07-21T15:58:16.53 10.0 undecidable manual PG 337 0.8214 -0.67 0.4
--.AQU.Z. 1987-07-21T15:58:14.74 10.0 undecidable manual SG 178 0.3663 0.16 0.6
--.MNS.Z. 1987-07-21T15:58:13.14 10.0 undecidable manual PG 236 0.6216 -0.13 1.5
--.ASS.Z. 1987-07-21T15:58:13.77 10.0 undecidable manual PG 302 0.6327 0.32 1.2
--.CM8.Z. 1987-07-21T15:58:10.40 10.0 negative manual PG 339 0.4995 -0.57 1.3
--.AQU.Z. 1987-07-21T15:58:08.52 10.0 undecidable manual PG 178 0.3663 -0.16 1.6
--.ALP.Z. 1987-07-21T15:58:07.00 10.0 undecidable manual SG 68 0.1332 -0.13 0.9
--.ALP.Z. 1987-07-21T15:58:04.55 10.0 negative manual PG 68 0.1332 0.17 3.1
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