Sky Quakes, Broken Gear, or Something Else.

[guyfriday]

There are a number of reports of earthquakes being registered as having a negative depth which would indicate that the epicenter is in the air. What I have right now is this (which i copied from my post over at ATS if it looks familiar to some):
2.7 quake 0.8km above ground USGS event, page 1 (abovetopsecret.com)

as of right now we have:
at 8:37 PDT a 1.2 over Big Bear California depth -0.4 Mi
at 2:12 PDT a 2.6 over Winthrop Washington depth -0.2 Mi
at 16:06 PDT on 9/12 over Kapowsin Washington depth -0.3 Mi
at 15:12 PDT on 9/12 over/at Milford Utah depth -0 Mi
at 12:39 PDT on 9/12 over Apple California depth -0.6 Mi
at 12:02 PDT on 9/12 over Mission Canada depth -0.4 Mi
at 11:13 PDT on 9/12 over Virginia City Montana depth -1.2 Mi
at 11:09 PDT on 9/12 over Bonadelle Ranchos-Madera Ranchos California depth -0.2 Mi
at 3:28 PDT on 9/12 over/at Alamo Nevada depth 0 Mi

That's all the possible in air or ground level quakes I'm showing for the past day or so. 

Can anyone figure out a link between these places, that would be great.

Any ideas or theories?

[Maxmars]

There are a number of reports of earthquakes being registered as having a negative depth which would indicate that the epicenter is in the air. What I have right now is this (which i copied from my post over at ATS if it looks familiar to some):
2.7 quake 0.8km above ground USGS event, page 1 (abovetopsecret.com)

Any ideas or theories?

This was offered as an explanation of negative depths in seismic reports in the Hawaii area... perhaps it's something similar reporting effect(?)
 

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Astute visitors to the USGS Hawaiian Volcano Observatory (HVO) website may have noticed that some recent earthquakes have negative depths. This does not indicate a change in seismicity but, rather, an upgrade in HVO's seismic data processing system.


The new system reports earthquake depths with respect to the common reference elevation, or datum, of sea level. When set to display earthquakes by depth, the HVO website map now includes a dark red color to indicate earthquakes that occur above sea level but below the ground surface. In the earthquake list to the right of the map, some events are now reported with negative depths.

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Not saying this is your answer, but it's worth mentioning. 

[l0st]

There are a number of reports of earthquakes being registered as having a negative depth which would indicate that the epicenter is in the air. What I have right now is this (which i copied from my post over at ATS if it looks familiar to some):
2.7 quake 0.8km above ground USGS event, page 1 (abovetopsecret.com)

Any ideas or theories?

I believe the initial alerts are automated. The alerts are then reviewed and updated manually by a ... geologist(? not sure what discipline studies earthquakes, specifically).

I know that other notable events have been revised after initial posting. Fukushima was one of those, but seems to happen pretty frequently from what I've observed.

Alternatively, someone set off a bomb above ground. Possibly some sort of mine or construction charges. Could just be some idiot in the boonies setting off tannerite.

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Not saying this is your answer, but it's worth mentioning. 

Pretty sure that's probably the answer. :)

[guyfriday]

This was offered as an explanation of negative depths in seismic reports in the Hawaii area... perhaps it's something similar reporting effect(?)
 

---

Astute visitors to the USGS Hawaiian Volcano Observatory (HVO) website may have noticed that some recent earthquakes have negative depths. This does not indicate a change in seismicity but, rather, an upgrade in HVO's seismic data processing system.


The new system reports earthquake depths with respect to the common reference elevation, or datum, of sea level. When set to display earthquakes by depth, the HVO website map now includes a dark red color to indicate earthquakes that occur above sea level but below the ground surface. In the earthquake list to the right of the map, some events are now reported with negative depths.

---

Not saying this is your answer, but it's worth mentioning. 

Good thought, I wonder if all those different regions would have the same issues though. California and Neveda but not Arizona. Montana is a real out layer given the Idaho wasn't affected. 
a new one:
at 15:26 PDT over Blodgett Oregon depth -0.3 Mi
Hawaii doesn't seem to be having this negative epicenter issue, nor is anywhere else in the world. Quite odd. 
Still your idea is currently as good as any at this point.

[l0st]

Good thought, I wonder if all those different regions would have the same issues though. Washington State but not Oregon. California and Neveda but not Arizona. Montana is a real out layer given the Idaho wasn't affected. 

Still your idea is currently as good as any at this point.

Much of Cali and Nevada are below sea level. I'm not sure about Arizona, though. What Maxmars posted would make sense in the context of those states.  Can't say I know too much about the terrain in Montana and Idaho either, except for potato and corn fields... and fly fishing in "A River Runs Through It" - great movie.

[guyfriday]

More negative altitude quakes today. 
at 9:21 PDT a 1.1 over Anderson Springs California depth -0.5 Mi
at 08:17 PDT a 2.4 over Midpines California depth -1.6 Mi
at 21:34 PDT on 9/13 a 2.7 over Dixon Lane-Meadow Creek California depth -0.7 Mi

One of the issues here the kind of disputes the location of the equipment is that there have been a few light tremors in locations near where some of these negative altitudes and those tremors are showing in ground epicenters. This might be some kind of unknown phenomena that hasn't been recognized, or sadly might be one that has been forgotten about. 

I wonder if a backlog of lightning strikes or better yet cloud to cloud, I guess we have to see thunderstorm histories, lightning might be the cause of these seismic hits.

[ArMaP]

More negative altitude quakes today. 
at 9:21 PDT a 1.1 over Anderson Springs California depth -0.5 Mi

I only looked at this one.
It's on a mountain, near a geothermal power plant, so it's no surprise it was above sea level.

One of the issues here the kind of disputes the location of the equipment is that there have been a few light tremors in locations near where some of these negative altitudes and those tremors are showing in ground epicenters.

The reason is not the location of the equipment, it's the way they measure it now, with reference to sea level.

Regarding in ground epicentres, do you know the definition of epicentre?

The point on the earth's surface vertically above the focus of an earthquake.

An epicentre is always on the surface, the original location (or focus) of an earthquake is the hypocentre.

I wonder if a backlog of lightning strikes or better yet cloud to cloud, I guess we have to see thunderstorm histories, lightning might be the cause of these seismic hits.

The Portuguese meteorological service has a record lightnings, so I suppose the US should have too, probably local, as lightnings are local events.

[guyfriday]

The Portuguese meteorological service has a record lightnings, so I suppose the US should have too, probably local, as lightnings are local events.

NOAA or the NWS should have this, I'll dig into this a bit. aka I might post another for a few days in this thread.

[ArMaP]

Another thing regarding lightnings.

As I said, they are a local event, and most are cloud-to-cloud, so they would not trigger seismographs several miles away.

Also, being an event with an extremely fast start, it would be recognisable on a seismogram.

[guyfriday]

Another thing regarding lightnings.

As I said, they are a local event, and most are cloud-to-cloud, so they would not trigger seismographs several miles away.

Also, being an event with an extremely fast start, it would be recognisable on a seismogram.

I know, but given the weirdness of these events, it's worth trying to rule items out.