Earthquakes: Greater Los Angeles area earthquake swarm - 2.5, 3.8, 3.0 and 4.0

Earthquake swarm is centered 1 km ( 1 mi) NNW of Yorba Linda, CA

M 2.5, Greater Los Angeles area, California
Thursday, April 23, 2009 9:04 PM
GPS Location: 33.909°N 117.778°W
Friday, April 24, 2009 04:04:51 UTC
Time: Thursday, April 23, 2009 09:04:51 PM at epicenter
Depth: 7.10 km (4.41 mi)

M 3.0, Greater Los Angeles area, California
Thursday, April 23, 2009 8:28 PM
GPS Location: 33.906°N 117.776°W
Friday, April 24, 2009 03:28:45 UTC
Time: Thursday, April 23, 2009 08:28:45 PM at epicenter
Depth: 2.30 km (1.43 mi)

M 4.0, Greater Los Angeles area, California
Thursday, April 23, 2009 8:27 PM
GPS Location: 33.910°N 117.768°W
Friday, April 24, 2009 03:27:50 UTC
Time: Thursday, April 23, 2009 08:27:50 PM at epicenter
Depth: 0.00 km (0.00 mi)

M 3.8, Greater Los Angeles area, California
Thursday, April 23, 2009 at 23:56:23 UTC
GPS Location: 33.896°N 117.795°W
Thursday, April 23, 2009 at 23:56:23 UTC
Time: Thursday, April 23, 2009 at 04:56:23 PM at epicenter
Depth:6 km (3.7 miles) (poorly constrained)

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Greater Los Angeles area earthquakes - Map
32 minutes ago Map 3.3
4 hours ago Map 4.0

A minor earthquake occurred at 8:28:45 PM (PDT) on Thursday, April 23, 2009.
The magnitude 3.0 event occurred 2 km (2 miles) NNE of Yorba Linda, CA.
The hypocentral depth is 2 km ( 1 mile).

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2.5 M Earthquake Details Magnitude 2.5 Date-Time Friday, April 24, 2009 at 04:04:51 UTC Thursday, April 23, 2009 at 09:04:51 PM at epicenter Location 33.909°N, 117.778°W Depth 7.1 km (4.4 miles) Region GREATER LOS ANGELES AREA, CALIFORNIA Distances 3 km (2 miles) NNE (22°) from Yorba Linda, CA 8 km (5 miles) ENE (68°) from Placentia, CA 9 km (6 miles) SW (214°) from Chino Hills, CA 13 km (8 miles) NE (52°) from Anaheim, CA 46 km (29 miles) ESE (111°) from Los Angeles Civic Center, CA Location Uncertainty horizontal +/- 0.3 km (0.2 miles); depth +/- 1.2 km (0.7 miles) Parameters Nph=078, Dmin=9 km, Rmss=0.45 sec, Gp= 36°, M-type=local magnitude (ML), Version=C Source California Integrated Seismic Net: USGS Caltech CGS UCB UCSD UNR Event ID ci10399905

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3.0 M Earthquake Details Magnitude 3.0 Date-Time Friday, April 24, 2009 at 03:28:45 UTC Thursday, April 23, 2009 at 08:28:45 PM at epicenter Location 33.906°N, 117.776°W Depth 2.3 km (1.4 miles) Region GREATER LOS ANGELES AREA, CALIFORNIA Distances 2 km (2 miles) NNE (28°) from Yorba Linda, CA 8 km (5 miles) ENE (70°) from Placentia, CA 9 km (6 miles) SSW (212°) from Chino Hills, CA 13 km (8 miles) NE (54°) from Anaheim, CA 46 km (29 miles) ESE (111°) from Los Angeles Civic Center, CA Location Uncertainty horizontal +/- 0.8 km (0.5 miles); depth +/- 1.3 km (0.8 miles) Parameters Nph=020, Dmin=9 km, Rmss=0.3 sec, Gp= 79°, M-type=(unknown type), Version=S Source California Integrated Seismic Net: USGS Caltech CGS UCB UCSD UNR Event ID ci10399897

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4.0 M Earthquake Details

Magnitude	4.0
Date-Time	Friday, April 24, 2009 at 03:27:50 UTC Thursday, April 23, 2009 at 08:27:50 PM at epicenter
Location	33.910°N, 117.767°W
Depth	0 km (~0 mile) (poorly constrained)
Region	GREATER LOS ANGELES AREA, CALIFORNIA
Distances	3 km (2 miles) NE (36°) from Yorba Linda, CA 8 km (5 miles) SSW (210°) from Chino Hills, CA 9 km (5 miles) ENE (69°) from Placentia, CA 13 km (8 miles) NNE (27°) from Orange, CA 47 km (29 miles) ESE (110°) from Los Angeles Civic Center, CA
Location Uncertainty	horizontal +/- 0.3 km (0.2 miles); depth +/- 0.6 km (0.4 miles)
Parameters	Nph=122, Dmin=9 km, Rmss=0.51 sec, Gp= 18°, M-type=local magnitude (ML), Version=C
Source	California Integrated Seismic Net: USGS Caltech CGS UCB UCSD UNR
Event ID	ci10399889

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Earthquake Details

Magnitude	3.8
Date-Time	Thursday, April 23, 2009 at 23:56:23 UTC Thursday, April 23, 2009 at 04:56:23 PM at epicenter Time of Earthquake in other Time Zones
Location	33.896°N, 117.795°W
Depth	6 km (3.7 miles) (poorly constrained)
Region	GREATER LOS ANGELES AREA, CALIFORNIA
Distances	1 km (1 miles) NNW (334°) from Yorba Linda, CA 6 km (4 miles) ENE (74°) from Placentia, CA 9 km (6 miles) ESE (109°) from Brea, CA 11 km (7 miles) NE (53°) from Anaheim, CA 11 km (7 miles) SW (217°) from Chino Hills, CA 45 km (28 miles) ESE (113°) from Los Angeles Civic Center, CA
Location Uncertainty	horizontal +/- 0.3 km (0.2 miles); depth +/- 31.6 km (19.6 miles)
Parameters	Nph=086, Dmin=8 km, Rmss=0.44 sec, Gp= 36°, M-type=local magnitude (ML), Version=O
Source	California Integrated Seismic Net: USGS Caltech CGS UCB UCSD UNR
Event ID	ci10399801