Earthquake Commentary for August, 2000

Map of recent earthquake activity

Send comments and suggestions

17:45 PDT, Thursday, August 31

The week's earthquake list totals 295 this week. Click here to see a summary and map .

08:44 PDT, Wednesday, August 30

Last night at 8:52 pm, a M3.5 quake was widely felt in the Ridgecrest and Inyokern areas. The epicenter was 5 miles northeast of Ridgecrest.

08:24 PDT, Monday, August 28

A pair of M3.0 Hector aftershocks occurred on Sunday, the first at 5:26 am, 38 miles north of Joshua Tree, and the second at 11:01 pm, 36 miles south-southwest of Baker. There were no public inquiries about either one.

14:47 PDT, Friday, August 25

A M2.9 quake occurred this morning at 11:57 am, in the Sierras 11 miles north of Lake Isabella. It was felt in the town of Lake Isabella.

18:37 PDT, Thursday, August 24

There was a M3.0 quake at 2:42 pm today, located offshore, 38 miles southwest of Mission Beach. We have no reports of it being felt.

The week's earthquake list totals 295 this week. Click here to see a summary and map .

08:18 PDT, Wednesday, August 23

A M3.4 quake occurred at 9:41 pm last night, located in the Coso Range, 18 miles east of Coso Junction. The focal mechanism was strike-slip. The quake was felt in Weldon, which is in the Sierras southeast of Lake Isabella.

08:51 PDT, Tuesday, August 22

We have another small Hector aftershock this morning, at 7:27 am. Magnitude was M2.8, and the epicenter was located 27 miles north of Joshua Tree.

14:55 PDT, Monday, August 21

There was a M3.3 Hector aftershock this afternoon at 2:28 pm. The location was 39 miles south-southwest of Baker. As this is a remote area of the Mojave Desert, we do not expect "felt" reports from the public.

19:22 PDT, Friday, August 18

A M3.7 quake occurred earlier this evening, at 6:01 pm, 5 miles northeast of Borrego Springs. The focal mechanism appears to be strike-slip, close to that of the nearby San Jacinto fault. The quake was felt as far away as Murrieta (near Lake Elsinore), Vista, and San Diego.

Not long afterwards, there was an unrelated M3.0, locate in the Coso Range, 12 miles east of Coso Junction.

17:48 PDT, Thursday, August 17

The week's earthquake list totals 228 this week. Click here to see a summary and map .

08:43 PDT, Thursday, August 17

At 9:43 pm last night, there was a M3.1 Landers aftershock (of the June 28, 1992 Mw7.3 Landers quake - remember that one?). The location was 17 miles north of Yucca Valley. It was reported felt in the small town of Landers. Although Landers aftershocks have become rare of late, due to the amount of time since the main shock, they have been continuing at a slow but steady rate. You can see this by looking at any of the weekly summary maps. The lineation parallel to the Hector sequence, just to the west, consists of Landers aftershocks.

10:02 PDT, Monday, August 14

The largest quake over the weekend was a M3.1 Hector aftershock, at 12:46 pm on Sunday. The epicenter was located 37 miles north of Joshua Tree. As far as we know, it was not felt.

There was a smaller Landers aftershock, however, at 12:02 am this morning, that was felt in Yucca Valley. Epicenter was located 2 miles east of Yucca Valley, and the magnitude was M2.6.

10:10 PDT, Friday, August 11

The largest quake overnight was a M2.9 at 7:09 am this morning, located 2 miles north-northwest of Frazier Park, close to the top of "the Grapevine" and close (about 1 miles) from the San Andreas. We have no "felt" reports on it, so far.

There was also a M2.7 Hector aftershock earlier, at 2:33 am. The epicenter was 36 miles south-southwest of Baker. This quake was not felt either, not surprising due to its remote location.

17:33 PDT, Thursday, August 10

The week's earthquake list totals 274 this week. Click here to see a summary and map .

11:30 PDT, Thursday, August 10

A M3.5 quake occurred early this morning (7:15 am), offshore about 7 miles west of Pismo Beach. It was felt as far away as San Luis Obispo.

08:20 PDT, Wednesday, August 09

The Hector sequence has been a little bit active during the past 24 hours. This activity included: a M2.7 at 12:42 pm yesterday afternoon, located 29 miles north of Joshua Tree; a M3.1 at 6:13 am this morning, located 37 miles north of Joshua Tree; and a M2.7 aftershock of the M3.1, at 6:30 am this morning, also 37 miles north of Joshua Tree. We have no "felt" reports for any of these quakes.

17:38 PDT, Thursday, August 03

The week's earthquake list totals 280 this week. Click here to see a summary and map .

08:56 PDT, Thursday, August 03

A M3.2 quake occurred very early this morning, at 12:06 am. The epicenter was located 3 miles northwest of Olancha, along the eastern front of the Sierra Nevada. There was a small swarm at this location in early July, the largest of which was a M3.4 (on July 9). We have received no "felt" reports for this morning's quake.

16:44 PDT, Wednesday, August 02

We had another Hector aftershock, M3.0, at 4:01 pm today. The epicenter was located 34 miles south-southwest of Baker. We've had no reports that it was felt.

15:25 PDT, Tuesday, August 01

The best location for the quake early this afternoon seems to be Latitude 33 deg. 55.6 min. N and Longitude 118 deg. 21.5 min. W. That puts it in the northwest part of the town of Hawthorne. The Community Internet Intensity Map indicates that it was felt most places between Torrance on the south and Santa Monica and West Hollywood on the north.

Note that the TriNet project , which has installed many more seismic stations in the Los Angeles Basin, allows us to deliver significantly more accurate locations in many areas, like Hawthorne, than we previously would have been able to do. We are still not at the "streetcorner" level, but our epicentral locations are probably good to within half a mile or less.

13:28 PDT, Tuesday, August 01

A quake just happened a few minutes ago in Hawthorne. The time was 12:53 pm and the magnitude was M3.0. The quake was felt in Santa Monica, El Segundo, South Gate, Inglewood, and El Camino Village, as well as, presumably, Hawthorne.

09:20 PDT, Tuesday, August 01

There was some action in the Hector aftershock sequence this morning. The first was a M2.6 at 4:09 am, located 23 miles north of Joshua Tree. The largest quake overnight occurred at 6:40 am this morning, 34 miles south-southwest of Baker. The latter was followed by another, M2.6, at the same location, at 8:35 am. The M3.4 might possibly have been felt, but we have had no reports.

This page is
Last updated 17:45 PDT August 31, 2000.