Boom/Shaking 11/17/11 west of Houston?

reply to post by jadedANDcynical


HKT.IU.00.LHZ.2011.321

Yesterday's seismo for Hockley. No local events on this page that I can see but a lot of microseisms and some big distant quakes which I will identify in a while. Just have to finish something else.

OK, here you go.



I often use VHZ to get an overall picture. You can see the 4 events clearly on HKT.IU.00.VHZ.2011.321

I don't see anything else of any consequence but the VHZ channel would not show small local stuff as it is 0.1 samples per second.

reply to post by TrueAmerican

And

reply to post by PuterMan


Thank you both very much for sharing your time and expertise in this matter. I would have been more than pleased with Eric/winston's assesment of, "I saw nothing." Having your further in-depth analysis adds not only additional data, but clarifying commentary.


Everyone else, these three (eric, TrueAmerican, and Puterman) are some of the ATS quake icons and if they say there was no quake, then it's a pretty safe bet to say that there was no quake, even a small one.

Microseisms (that PM mentions) could have a variety of cause including, but not limited to, industrial activity, ocean activity, or transportation (trains, heavy machnery, etc) to name a few, they are not necessarily tied to tectonic action.

Still nothing on the news so far.

reply to post by jadedANDcynical


Mm, maybe not nothing however. I don't know how this relates timewise to the boom but here is the spectrum for the whole day and you can see a 4hz signal and a clear signal around the 9hz mark. These are not seismic by the way.



I haven't listened to it yet.

reply to post by PuterMan


Hmm, well that spectro is interesting. Except there is no timeline at the bottom, so how is one supposed to divide up the hours of the day on that? Cause I believe from statements in thread, it happened somewhere between 6 pm to 8 pm. And usually a good bit of the signal on these noises resides above 10 hz (out of range of this spectro), so if it is shown, only the very low frequency component (up to 10 hz) of the noise is shown. And why is 4 hz so hot? That's weird.

reply to post by TrueAmerican


My apologies I had not noticed I had cut the top off. Here it is again with the times across the top.

reply to post by PuterMan


ok, thanks. And now that I see it, do you see anything between that time period (6 to 8pm) that is strange, relative to the rest? I don't-

Generally speaking, the noise usually has much higher frequencies in it, cause I remember doing a spectro of it in one of the first threads on the subject.

reply to post by TrueAmerican


IU_HKT _BHZ_Day321-Complete_8000sps.wav 9.1 Mb Unfiltered 400 x speed
IU_HKT _BHZ_Day321-Complete_8000sps_LP5.wav 9.1 Mb filtered 5 Hz 400 x speed
IU_HKT _BHZ_Day321-Complete_22050sps_LP5.wav 3.3 Mb filtered 5 Hz about 2000 x speed.

The sound files of the whole day. You can hear the 4 quakes and nothing much else. I guess the sound did not register on the seismo and there was no seismic event other than the 4 I have identified.

Is that spectro time local or UT?

Something else for you to consider is that, while this is the closest seismo from the reported location it is approximately 18 km+ distant.

Here is an interesting snippet:

In the Earth's atmosphere, the most important factor affecting the speed of sound is the temperature (see Details below). Since temperature and thus the speed of sound normally decrease with increasing altitude, sound is refracted upward, away from listeners on the ground, creating an acoustic shadow at some distance from the source.

wiki

PM, I can plainly see the signal at 4hz, it appears to shut off and back on quite abruptly seveal times. The signal @ 9hz, is that the wider band that looks like a zig zag stitching that ends in a narrow band that looks to be about 8.5 Hz?

What would cause signals in that range? Unless im'mistaken, both of those are well below the range of human hearing so they would not even related to the noise.

I am west and slightly north of Katy and about 20 miles from Hockley. We did not hear it but got a call from friends up near Hempstead asking if Brookshire had exploded. They heard it and thought it came from this direction. We are south of Hempstead about 20 miles. (everything seems to be about 20 miles from me) I have not seen anything on the news either.

We have had the helicopters over our house too. I thought it was an Apache. Scared me *****less. It flew around a few times and then pointed nose down right at us. We were in the back parking area at the time between the garages.

Haven't been to Moes in a long time. There is a great little place out in the country that we frequent. If anyone wants the info let me know via U2U. Not sure if its ok to give their website or not.


ETA: We were eating dinner so time would have been 6 to 7PM

Per my husband there is a pipe testing facility in Waller and they were pressure testing pipe with nitrogen. It went boom when the pipe failed.

reply to post by TXTriker


That's the right vicinity and I'm guessing you confimed the time with him to match up with the reports in the area.

It seems like the mystery is solved (or has at least a plausible explanation), thanks to the rigor of ATS members.

reply to post by wytewingdove


Was any of this reported on any local news station? We get them here in Hampton Roads area of Virginia. ( Norfolk, Va Beach, Hampton, Chesapeake, Suffolk, Portsmouth, Newport News ) and enough people were reporting it that it made the local news. No answers from any authority as to what it might be. We have a lot of military in this area but so far none are claiming responsibility for the booming or shaking.


www.wvec.com...


www.bbsradio.com...

reply to post by jadedANDcynical


He actually got the initial phone call from friends about it during dinner. He works about 6 miles south of Waller. The landlord for the business premises owns about half of Waller. I'm pretty sure that's where the info came from. Also the landlord owns the local newspaper so I imagine they investigated. I think the testing facility is relatively close to the newspaper office.

Waller is a relatively short distance from Hockley so it could very well have affected the seismo there.