What's Going on at Long Valley?

Just like with Mt. Hood, probably nothing.

However, there was a little bit of slightly above average earthquake activity there today, in the vicinity of Mammoth Lakes.

1.9 2010/05/21 18:06:07 37.821 -118.978 2.0 20 km ( 12 mi) SE of Lee Vining, CA
1.6 2010/05/21 18:04:52 37.819 -118.959 6.2 20 km ( 13 mi) N of Mammoth Lakes, CA
3.0 2010/05/21 18:03:48 37.818 -118.971 3.9 20 km ( 12 mi) N of Mammoth Lakes, CA

Details on that 3.0:

Friday, May 21, 2010 at 18:03:48 UTC
Friday, May 21, 2010 at 11:03:48 AM at epicenter
Time of Earthquake in other Time Zones
Location
37.818°N, 118.971°W
Depth
3.9 km (2.4 miles)
Region
CENTRAL CALIFORNIA
Distances
20 km (12 miles) N (2°) from Mammoth Lakes, CA
20 km (13 miles) SE (140°) from Lee Vining, CA
38 km (24 miles) NW (318°) from Toms Place, CA
233 km (145 miles) ESE (110°) from Sacramento, CA

Just starting a thread in case there are more. This may very well be all the activity we see. (Other than the usual very small quakes that occur in the region every day.) Giving this its own thread because Long Valley's a pretty geologically significant place. (Being a supervolcano caldera and all.) Current scientific opinion seems to be that the most likely next eruptive activity in the area will be just one vent, like Mammoth Mountain. (So, not a catastrophic event.)

More Long Valley quakes today:

(These were all added after the 1.9 I finished with yesterday.)

1.9 2010/05/22 17:09:31 37.819 -118.971 1.3 20 km ( 13 mi) SE of Lee Vining, CA
3.2 2010/05/22 17:06:07 37.819 -118.975 4.1 20 km ( 12 mi) SE of Lee Vining, CA
1.9 2010/05/22 10:29:41 37.819 -118.971 3.2 20 km ( 13 mi) N of Mammoth Lakes, CA
1.5 2010/05/22 10:06:11 37.483 -118.804 9.2 14 km ( 9 mi) SW of Toms Place, CA
2.3 2010/05/22 09:56:39 37.822 -118.978 1.9 20 km ( 12 mi) SE of Lee Vining, CA

These do appear to be occurring on or near a fault.

Three more:

2.5 2010/05/22 18:36:48 37.814 -118.967 3.2 20 km ( 12 mi) N of Mammoth Lakes, CA
1.4 2010/05/22 18:30:12 37.820 -118.978 1.8 20 km ( 12 mi) SE of Lee Vining, CA
2.9 2010/05/22 18:24:07 37.816 -118.969 3.7 20 km ( 12 mi) N of Mammoth Lakes, CA

Hoping West Coast or Puterman or some of the other Yellowstone watchers will jump in and start looking at this.

A concerning thing from the seismos:

look at the 2 events that occurred at 18:04 and 18:06 utc today. If I saw that on a seismo at Yellowstone I'd say it was human noise, but they were recorded as quakes. Does it not look a little bit long period?
D'oh! Make that between 17:34 and 17:38. Maybe it is just noise or a mine explosion somewhere but it does show up on graphs all over the area.



Here's the closest station, which is bound to be a bit messy:

earthquake.usgs.gov...

but also see it at Convict Lake:

earthquake.usgs.gov...

and Convict Morraine:
earthquake.usgs.gov...

It doesn't show up at the Deep Hole station, though. Maybe an explosion? I'll be interested to see if those two quakes are removed, or if there was some kind of hydrothermal explosion there today.

It does show up as a very light trace on the Deep Hole graph.
earthquake.usgs.gov...





[edit on 22-5-2010 by quakewatcher]

[edit on 22-5-2010 by quakewatcher]

and going...


1.3 2010/05/22 19:53:16 37.621 -119.037 5.2 5 km ( 3 mi) WSW of Mammoth Lakes, CA
2.7 2010/05/22 19:39:54 37.815 -118.967 2.4 20 km ( 12 mi) N of Mammoth Lakes, CA

[edit on 22-5-2010 by quakewatcher]

reply to post by quakewatcher


I think that one is probably the 4.9 at Baja @ 17:30 UTC and the 4.8 @ 17:33 showing up. Not sure about the timing but you can clearly see two quakes P & S waves arriving and there is about 3 minutes between then

That would be my guess anyway. Otherwise not too bad. Some nice clean spikes to look at.

That makes total sense. I forgot to check for teleseisms. Thanks.

Ooops, wrong thread!

Sorry.

[edit on 22/5/2010 by PuterMan]

I think this is most definately something to keep an eye on. Especially since all that energy seems to be going right up the coast!

That 'line' was the first thing I noticed. Most likely the 4.9 quake...did you check into that? If not, it adds a bit more...drama to the situation.

I think most people forget about this caldera...but all you have to do is take into consideration where it is, and it doesn't have to be all that big to make a HUGE impact!

S & F

Just when you thought it was safe to go back in the water...

? 2010/05/23 04:56:02 37.815 -118.968 3.1 20 km ( 12 mi) N of Mammoth Lakes, CA
3.1 2010/05/23 04:45:44 37.817 -118.971 3.9 20 km ( 12 mi) N of Mammoth Lakes, CA
2.2 2010/05/23 04:16:26 37.490 -118.809 8.8 14 km ( 9 mi) SW of Toms Place, CA
2.0 2010/05/22 21:15:38 37.815 -118.968 1.2 20 km ( 12 mi) N of Mammoth Lakes, CA

curious to see the magnitude of that new one. (question marks usually turn out to be small.)

update: latest was a 2.7, so not that small.

[edit on 23-5-2010 by quakewatcher]

Thanks quakewatcher for the heads up.

Some further information:

hisz.rsoe.hu...



Is it just me or the quake depths getting generally closer to the surface?

Suggesting possibly the movement and rising of magma up the chamber?


Date Time Mag Depth

2010-05-23 04:56:02 2.7 3.60 Km
2010-05-23 04:45:44 3.1 3.90 Km
2010-05-23 04:16:26 2.2 8.80 Km
2010-05-22 09:56:39 2.3 1.90 Km
2010-05-22 17:06:07 3.2 4.10 Km
2010-05-22 18:24:07 2.9 3.70 Km
2010-05-22 18:36:48 2.5 3.20 Km
2010-05-22 19:39:54 2.7 2.40 Km
2010-05-21 18:03:48 3.0 3.90 Km
2010-05-18 06:04:59 2.4 6.50 Km
2010-05-18 23:41:38 2.7 5.40 Km
2010-05-17 21:24:59 2.1 6.20 Km
2010-05-17 20:56:21 2.6 5.40 Km
2010-05-03 14:44:59 2.1 13.50 Km
2010-04-25 00:40:11 2.3 12.10 Km
2010-04-23 17:55:29 2.2 36.20 Km
2010-04-09 02:25:53 2.6 18.00 Km
2010-04-03 20:44:38 2.6 6.00 Km
2010-04-02 06:00:38 3.9 10.00 Km
2010-03-31 17:42:08 2.2 4.90 Km
2010-03-31 06:46:10 2.1 7.40 Km
2010-03-26 10:18:03 2.7 9.20 Km
2010-03-24 19:03:21 2.3 18.90 Km
2010-03-19 05:42:46 2.2 6.60 Km
2010-03-18 14:48:38 2.3 10.10 Km
2010-03-18 02:48:59 2.4 4.20 Km
2010-03-17 22:50:22 2.7 12.10 Km
2010-03-16 21:00:10 2.6 10.00 Km
2010-03-10 05:16:34 2.2 6.00 Km
2010-03-07 03:07:39 2.8 14.50 Km
2010-03-03 23:52:31 2.1 19.90 Km

Also, do not want to sound like an alarmist but can anyone confirm or correct me regarding all the Baja activity that seems to be daily since the 7.2 in March. Could this activity be eminatting in a an indirect or deferred manner from Long Valley?




[edit on 23-5-2010 by Skellon]

RSOE will only show the larger quakes, I think USGS is a better source for complete (and most recent) data. (Especially for plotting major trends) That said, the last few small quakes have been very shallow.

1.8 2010/05/23 11:44:32 37.816 -118.962 1.7 20 km ( 12 mi) N of Mammoth Lakes, CA
1.9 2010/05/23 10:20:28 37.823 -118.972 3.2 20 km ( 12 mi) SE of Lee Vining, CA
1.9 2010/05/23 05:44:25 37.820 -118.976 0.8 20 km ( 12 mi) SE of Lee Vining, CA
1.8 2010/05/23 05:04:56 37.819 -118.972 1.1 20 km ( 13 mi) N of Mammoth Lakes, CA

.8 km for that first 1.9. It's important to keep in mind though just how much CA does shake. Without knowing more about what's going on in the ground it's really hard to say what is going on.

pleased that long vally has his own threat now...:-)

I was warning an long time ago at several other fotums on ATS for it...

earthquake.usgs.gov...

volcanoes.usgs.gov...

p/s... do we need to save tom's hut?



[edit on 24-5-2010 by ressiv]

More quakes:

1.1 2010/05/24 16:42:54 37.822 -118.978 0.7 20 km ( 12 mi) SE of Lee Vining, CA
2.2 2010/05/24 14:39:37 37.439 -118.617 14.2 3 km ( 2 mi) NNW of Round Valley, CA
1.9 2010/05/24 00:45:01 37.827 -118.985 0.1 19 km ( 12 mi) SE of Lee Vining, CA

The Round Valley quake is pretty far from the others, to the Southeast. Note the extremely shallow depth of the other two. Fortunately, nothing over a 2.0 in the swarm area for more than 24 hours now.

None of the stations are really located all that close to the swarm, so we can't really see if there's any smaller activity going on.

Picking up again. Again I'm wishing for monitoring closer to the action. From reading the LVO site it looks like they aren't even really monitoring gas in that area. (Why no close stations when the area is littered with craters?)

2.2 2010/05/25 04:31:27 37.822 -118.977 1.9 20 km ( 12 mi) SE of Lee Vining, CA
1.4 2010/05/25 04:00:04 37.479 -118.784 5.7 13 km ( 8 mi) SW of Toms Place, CA
1.9 2010/05/25 00:19:29 37.482 -118.784 6.4 13 km ( 8 mi) SW of Toms Place, CA

The Lee Vining quake is in the region of the swarm from this weekend. The Toms Place quakes are shaping up to be their own little swarm.

Several quakes right along the rim of the caldera today:

earthquake.usgs.gov...

1.1 2010/05/27 04:39:48 37.596 -118.819 8.0 13 km ( 8 mi) WNW of Toms Place, CA
1.9 2010/05/27 00:11:58 37.627 -119.047 5.0 6 km ( 4 mi) W of Mammoth Lakes, CA
1.7 2010/05/26 19:23:58 37.630 -119.047 5.1 6 km ( 4 mi) W of Mammoth Lakes, CA

Small, but the placement is interesting. I'll be interested to read the weekly report this Friday.

I see nothing out of the ordinary.
These small swarms have been happening every since i worked builting the geothermal power plant there.

You get the same type swarms at Coso geothermal and the Geysers geothermal.
en.wikipedia.org...
www.popsci.com...

I've been watching the swarms at Coso and the Geysers, but I don't remember seeing quite the same thing looking so organized at Long Valley. (From the Satellite images I don't think it's centered at the geothermal plant.)

Whether or not it's a good idea to have induced seismicity in such a volcanically active region is another topic...

More this morning, very shallow.

1.4 2010/05/27 11:49:44 37.828 -118.978 0.4 19 km ( 12 mi) SE of Lee Vining, CA
1.4 2010/05/27 09:10:50 37.821 -118.973 0.7 20 km ( 12 mi) SE of Lee Vining, CA
1.4 2010/05/27 08:43:46 37.825 -118.983 1.6 19 km ( 12 mi) SE of Lee Vining, CA

Latest update from the Long Valley Volcano Observatory:

LONG VALLEY VOLCANIC CENTER VOLCANO (CAVW #1203-14-)
37°42' N 118°52'12" W, Summit Elevation 7231 ft (2204 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Thirty six earthquakes between magnitude M=1.0 and M=3.0 occurred in the Long Valley region since the last update at 3:03 PM (PDT) on May 21, 2010. Twenty two of these occurred in a swarm that began with the M=3.0 earthquake at 11:03 AM on the 21st noted in last week's update. This swarm was centered at a depth of approximately 5 km beneath Little Sand Flat ~ 5 km (3 miles) east of the southern end of the Mono Craters chain (20 km or 12 miles north of Mammoth Lakes). The swarm included four M>3 earthquakes, the largest of which was a M=3.5 event at 10:06 AM on the 22nd. The swarm has largely quieted down as of this update but continued to produce occasional M>1 earthquakes through yesterday evening. We have detected no ground deformation associated with this swarm and see no other evidence that it might be associated with a magmatic intrusion. Low-level earthquake activity elsewhere in the region continued with little change from the past several weeks.

MAP 3.2, 2010/06/07 22:31:21 , 7.641 -118.942


MAP, 3.0 2010/06/07 22:31:30, 37.637 -118.954 , 6.6


MAP 2.8 2010/06/07 22:40:25 37.642 -118.942


LONG VALLEY AREA, CALIFORNIA

top three quakes


earthquake.usgs.gov...