*Addendum* There are of course loopholes to this argument, for instance there may be higher order quantum gravity effects which violate Lorentz invariance [3]. Either way the result will be hotly debated - is it an unknown systematic error or some exciting hint at new physics?
So your out-of-hand rejection of the OPERA result is stronger than the comments of the people that you cite in support of your position. That's not a very logical position. You may be right to reject "new physics" on the basis of the OPERA result - you may very well be right - but this datum isn't strong enough to claim that you're right by reasoning, rather than by luck.
FWIW, I'm sceptical of the OPERA results too, but I'm hopeful that they are right. What we do know is that there are big problems at the base of physics - GR being a classical theory of gravity and the Standard Model being a quantised model of the other forces, which suggests that something is wrong there.
Frosty pint? No thanks, I had enough last night and I've got a bit of a hangover. Besides, we've tickets for "Under Milk Wood" this afternoon, which manages to get through to even my philistine mind.
Being "recklessly negligent" has a very specific meaning : it means that you do not consider at all something which a reasonable person should have considered. It does not mean that you reckoned the odds and got it wrong.
I'm not disagreeing that TEPCO's various technical and financial calculations were incorrect. But that is a different thing to being "reckless", in both legal and moral senses.
(There are specific charges in the legal system that I work under that make a very clear distinction between actions that are "reckless" and ones that are ill-advised or poorly judged. For example, a case that a friend of mine in the trade union business was involved in a couple of years ago involved a building contractor one of whose workmen was injured when a trench collapsed. The contractor claimed that he'd been planning to shore the trench up when it got to a certain depth, and had made an error of calculation about what that depth should have been. The trade union (acting for it's injured member) asserted that, because there was no shoring material - boards and scaffolding poles - nor a plan for the shoring on site, then the contractor had been reckless - he'd completely ignored or not considered that risk. The judge found the contractor had indeed been recklessly negligent, and doubled the damages.)
What did Churchill say? Something about "two countries being so divided by sharing a common language"?
In spring the ice will block the water and create a flood (which will then wash aways the ice).
That depends entirely on where they choose to put the ice block.
I don't know about you, but I suspect that the Mongolians are just as capable of thinking about this as you are, and working to avoid such problems. (It's even just about possible that one of them reads Slashdot, and is striking their forehead and saying "Doh!" at this very moment.)
to protect the driver and passengers from crimes that often occur in taxis.
I can't think of a single example ever of a crime that has been perpetrated on a taxi driver or passenger by someone who was not also a passenger in the taxi. Plenty of cases of passengers robbing drivers ; no shortage of disputed fares ; but no people coming into a taxi to commit a crime against the driver or passenger who is already there.
For which case, CCTV or still imaging is appropriate, with no need for sound recording. (Some of the taxi companies in this city already use, and advertise, in-taxi photography. It's a straight commercial decision, reducing their insurance costs. And the bus company has CCTV fitted to all buses for the same reason.) For disputes over fares... well the first thing a driver does after picking up a fare is radio to base "picked up from X to Y", which conversation is recorded at base. And on a number of occasions when scrotes have tried it on, they have found themselves on the receiving end of 4 or 5 other drivers performing a citizen arrest using reasonable force. And wheel wrenches.
Taxi crime isn't a major problem in this town.
I suppose I'd better RTFA now, but it's probably just some snotty nosed little jobsworth bawling to get attention and have his nappy changed. Oh, I see one link is to the Daily Flail. excuse me for not falling off the sofa in surprise.
...And what created the biggest flood waters to hit the plant ever? An earthquake.
Err, unless you're using a different meaning of "biggest", "flood", or "ever" to me and the dictionary . . .
Hang on - I read what you wrote as being "planet", not "plant", but "plant" makes sense as well.
On my mis-reading as "planet", the biggest flood waters to hit the planet ever were either the draining of Lake Missoula across the "scablands" of NW USA (see this summary and references therein) about 15,000 years ago, or one of the several re-fillings of the Mediterranean Sea basin after their desiccation in the Messinian Salinity Crisis (around 5 million years ago). There is an outside possibility that the Zechstein flood(s) 250-odd million years ago were bigger, but given the tectonics of the Mediterranean (a true ocean), I think the Messinian floods would have been volumetrically bigger. The flow through the Viking-Central graben series woulf have been pretty damned spectacular though.
OTOH, if you were actually referring to "the plant", then the history of the particular site is beyond me. However on general principles I'd expect any randomly selected part of the Japanese coastline to be subject to significant vertical motion on pretty short (10s of thousands of years) time scales. which should give pause for thought for locating things like nuclear waste repositories. But then again, all the volcanicity would rule Japan out for that sort of thing anyway.
Everyone did their best and it was simply an event beyond what anyone thought was possible.
That's still a touch too black-and-white ; the earthquake and tsunami were always possible, but they were not considered a sufficiently high probability to be designed against. Those probability assessments have no doubt been revised.
Other commentators are forgetting that there is a reason the reactors were built at sea-level : they need the cooling water. Putting them (say) 100m above sea level would increase the power requirements for pumping cooling water up to the plants, which would mean that you need more (or bigger) power stations. (Plus, of course, putting them on hillsides would increase the risk of ground instability in a large earthquake.)
The design of these structures was rational. Some of the design assumptions (e.g. the probability of earthquakes of magnitude X) may have been incorrect, with hindsight, but that is a different thing from being recklessly negligent.
Hmmm, on the scale of public insanities, that's relatively sane. I see a lot of "may" in there, which is going to make it a bit hit and miss depending on your area, but that's worth re-reading if I find myself sent to Canada again.
1-1-1 is not available in the NANP, because 11 is the prefix used to access...
More significantly... when you've got a broken line (the typical excavator bucket going through a line type of accident), you're going to generate a lot of [pulse-pause-pulse-pause-pulse] signal trains from random contacts, and that is going to generate a flood of "calls" when there is an incident. When the EU mandated the use of "1-1-2" as a pan-European emergency services number they missed this possible failure mode, which has led to such incidents since then. "1-1-1" would be even more subject to the problem.
Not me, you stupid Septic. I was in the pub last night enjoying myself with a couple of other friends who also work in the oilfield (well, hell, this is a town with about 20% of the economy made up of oil service companies ; quelle surprise!), one of who comes from the Fylde and wanted to understand what the situation is. So I gave him my best opinion, because he asked politely and paid attention to what I was saying. And we arranged to maybe go hill-walking at the weekend too. Double-plus good.
Your insinuation that I'm paid to write this sort of stuff is deeply insulting. And wrong.
Yes I do work in the oil industry. And I'm not at work (though I will be in the office tomorrow). I do actually have opinions of my own. And I also do know a lot more about the process than you do.
That hydraulic fracturing can trigger earthquakes isn't an issue. That has been well demonstrated by the late 1960s Colorado waste disposal well - it's been literally a text book example since at the latest the late 1970s. I'm glad to see that the USA EPA have caught up on thirty-year-old text books - though given the US Govt's predilection for having shit in it's science textbooks, the case study may have escaped a generation or two of American geologists.
That some major earthquakes have fore-shocks is an observational fact. Whether that is relevant to the Oklahoma quake in particular is a different question. The USGS don't seem to think so.
Could the release of strain through the small fracturing-related earthquakes trigger the release of a larger earthquake? Well only a fool would say it was impossible, but up-thread I gave some energetics reasons why I doubt it's likely in this case. The USGS seem to think it's not the case too, and they know the area and it's stress fields much better than I care to find out (I'm much more concerned with the stress field of the Rumfiji Basin).
Anyway, you can go shove your fucking head up your cum-soaked arse if you think that I wrote that because I was paid to - I wrote it because I'm actually interested in the reality of what is going on. But since you seem to think that disagreement with you makes me automatically a shill, well fuck you. Stupid fucking American wanker, you deserve the government and corporate abuse you get.
Oh, incidentally, it is clear from the following that you do not understand one fucking thing about hydraulic fracturing:
Great, you pump in pressurized liquid to replace the gas, also great
Well done, fuckwit, you've just given a basic description of waterflood injection. Which is a completely different process. So, dumbfuck, go find yourself someone who is willing to spend their time explaining the difference to you. (Actually, we have a course in that in the training brochure. I think you'd get a little change out of $5000.)
with airline carry-on luggage restrictions and get a 4" diameter, 10" long aluminum cylinder through airport security is going to be a pain.
4in diameter by 10in long? That would fit perfectly well in my briefcase. I might have to ditch the full-size laptop into hold-baggage, or carry a netbook instead of it, but I doubt that would be a serious problem. I might put a T-ring adaptor onto it and a couple of other lenses in the briefcase too, so it looks like a big lens and could be connected to the camera to prove it. It is a big lens, after all. Hand carry. Unload the laptop into it's separate tray (depending on airport regulations and phase of the Moon) and ask the security guard if they want the camera equipment to go through separately too? Shoes off today, or not? Already emptied all my pockets into the zip-up pockets of my jacket, so that goes into a tray. Watch off. Walk through the metal detector.
A telescope of that size is nothing but a large lens. You don't have to tell them that you've got a CCD detector in the hold baggage (or in the wife's hand-carry) along with the tripod. You don't have to fire up Maxsim on the netbook.
Oh, I'd try to find a recent copy of S&T or Astronomy now with an article about how to use a 4x10 scope to photograph the Transit. Keep that rolled up in the inside pocket of the jacket. Or carry a photo magazine with an article about shooting motor racing (or across the length of a sports field using a monster lens. But be prepared to "talk the talk."
Threats from Space?
Asteroids and comets are probably the biggest threat. We *know* no dinosaur killer is on its way here for at least a century or three, so that's cool.
Sorry to call you out Phil, but we don't know that. We are reasonably confident that there are none-such in the approximate plane of the ecliptic. Outside the plane of the ecliptic, we don't know that. And Phil knows his astronomy well enough to know that the orbital inclinations of long-period or sporadic comets are more-or-less randomly distributed. It's one of the main pieces of evidence that people have used for decades as grounds for talking about a more-or-less spherical "Oort Cloud" as opposed to a more toroidal "Kuiper Belt".
An impactor coming in from over one of the Sun's poles, looping around at perihelion and then coming barrelling down our throats... would just about give us enough time to say a comprehensive "Stercus, stercus, stercus, moriturus sum!" before bending over and kissing (something) goodbye. And with the perhelion approach, we wouldn't know if it was going to be a hit or a miss until the fat lady was gargling and the amplifier was going up through 10.5. To mix several metaphors.
None of which quibbles decreases my enjoyment of the blog any!
Well, despite you being an AC, people are listening to you.
The bombing target idea works for a lot of things. But what about the structure at 40.422906 Lat, 90.786896 Long ? It's about 200km west of the original cluster of artefacts. I say "about" because measuring the distance any more accurately is pointless. The damned thing is over 5km by 10km !
I really don't want to think about desiring to test bombs that can have a blast radius of several km or more. We have nukes in that range - do we need conventional weapons like that.
The high reflectivity is puzzling. Maybe a solar power installation? The site has cooling towers, what looks like liquid storage tanks, elongated buildings. Very odd.
Several people have replied somewhat sarcastically. I'm not being sarcastic.
Look at the X million tonnes of material you see on the highway ahead of you, heading east. And you think that may have an effect on the Earth's rotation?
What about the almost-exactly-X million tonnes moving west on the other side of the highway? That is going to have almost exactly the same effect but in the opposite direction.
The effects very largely cancel out.
Rebuttal style two : the wheels push against the road to push the vehicle forward. The vehicle needs to be pushed forward against friction from the air. The air doesn't all just pick up and follow the vehicle because of friction of the against the ground. That friction against the ground, when averaged out through eddies etc, acts in the same direction and to the same amount as the push of the wheels, but in the opposite sense. There is no net effect.
I remember in my physics homework being given thought experiments about inertia :
a man stands in a canoe in a lake with a bucket in his hand. He walks from one end of the canoe to the other. Does the canoe move? Explain your reasoning.
a man stands in a canoe in a lake with a bucket in his hand. He walks to one end of the canoe, fills his bucket at the end of the boat, then walks to the other end of the canoe and empties the bucket over that end. Does the canoe move? Explain your reasoning.
You can guess from the form of the problem that the two answers are different. The marks come from explaining your reasoning.
Actually, the Denver injection is a textbook case - and has been for at least 30 years. But the point should also be made that that case was the bulk disposal of hundreds of thousands of gallons of fluid over periods of years, which is orders of magnitude greater than a hydraulic fracturing job, which rarely lasts more than a few days of actual operations. (Rigging up and tearing down equipment may take much longer, as may drilling the well itself.)
It is perfectly possible (...) that the process used in hydraulic fracturing (...) is altering the crust in a way nothing else would, and hence is generating earthquakes that otherwise would never have existed in the first place.
What is your proposed mechanism, and how does it differ from the mechanisms that lead to the frequently-observed natural mineral-filled fractures in many rock formations? (You may not observe them ; I'm a geologist, and I observe more rock, more closely, than the large majority of people ; I see them very frequently.) What predictions do you make of observations that would differentiate your hypothesised mechanism from the existing model of natural fracturing by dewatering of sediment under diagenesis?
This is actually asking whether fracking is causing additional stress that eventually leads to earthquakes. Adding stress does not, in fact, make earthquakes less serious.
That's easily worked out. How many cubic metres of fluid were injected into the tubing at what pressure? That will give you the amount of work done. (Pressures will fluctuate somewhat, so you'd need to integrate the data not use one number for volume and a second for pressure. But that's trivial.) Compare the work done - the energy put into the system - by the high pressure fluid to the work done by the earthquake(s).
Do you care to bet which factor is many factors of ten larger? I know where I'd put my money (if I were a gambler).
Don't know if there's any correlation, but since USGS tracks these things, the data should be available from the EQ side
The USGS certainly do make a lot of earthquake data available. I've been trying to get the corresponding data from the BGS, but their new historic data page has serious UI issues (under FireFox?).
just need to time correlate it to when/where extraction operations occurred.
Err, fracking is an INJECTION operation, not an extraction operation. Hydraulic fracturing prepares a well for gas (or oil) extraction. Then, the fracturing is finished, the well is flowed (to clean up and to check that the fracturing has achieved the production improvements desired), then suspended while the rig dismantled while a production flowline is installed.
Hmm...the big Oklahoma quake was 3.1 miles deep (the smaller quakes leading up to it were around 2.5 - 3.5 miles deep). Fracking wells are typically 1 to 4 miles deep.
The Woodford shale formation under Oklahoma ranges from 5000 - 12000 feet. (around 1 to 2.25 miles)
You're getting confused between MD, TVD and TVDss (which is very common). That's Measured Depth (distance measured along the borehole, by measuring the lengths of pipe you're running into the hole) versus True Vertical Depth (the distance from the bottom of the hole perpendicularly to the altitude of the drilling rig's measurement point) versus True Vertical Depth sub-sea (which is TVD referenced to mean sea level, because ground level isn't level, and not all drilling rigs have their measurement point at the same height from the non-level ground ; for comparison between wells and across fields).
The hypocentre depth you give for the quake is 3.1 miles (converted from the 5km that the USGS cite? This is a science-tech website, not a historical-studies website.) either TVD or TVDss (probably TVDss).
The depth you give for the Woodford Shale is also most likely also a TVD or TVDss (what is the elevation of Oklahoma? That'll give you the difference between the two.), so you're saying that the target formation for the hydraulic fracturing operations is 1.36km (0.85 miles) above the hypocentre of the earthquake under discussion.
The 1.6 to 6.4km ("1-4 miles") you cite for a "typical" hydraulic fracturing well clearly implies, given your depths for the target formation, that the wells are "extended reach" or "horizontal" wells, where the main wellbore is at a considerable angle to the vertical, and you can have up to a 2000m of wellbore drilled parallel to the bedding ("horizontal", though if the target formation isn't horizontal, the terminology gets confusing!) at essentially the same TVD / TVDss. It is incredible that the well(s) would have penetrated significantly below the target formation, because that would increase costs for no commercial benefit. (There are engineering reasons to penetrate a small distance beyond the reservoir. For example, to allow long logging tools to pass the whole target.)
The popular press only understand one thing by "depth" ; in the real world (well, if you can call the oilfield that ; few insiders do!) there are several possible, reasonable, answers to "what depth is this hole?" To that extent, our in-house software contains a tool for converting between all 3 measures cited above, because the function is called on so often.
Thought experiment -- imagine a church wall supported above an arch.
That's a poor analogy.
Firstly, the natural gas is not in "big holes in the ground" (which I assume you're modelling with your arch). It's in the interstices between rock grains, which themselves are supporting the main part of the weight of the overlying rocks (what we geologists call "matrix stress"). So, by removing the gas from a part of your wall (not that that's what is happening), a better analogy would be of a wall with one part having a strength of (say) 60MPa (your gas-filled rock) and 70MPa (for the bulk of the wall.
Now your model is better, but still badly wrong. In fracturing (whether it be hydraulic, explosive, or whatever) the fracture propagation will be in a direction perpendicular to your minimum compressive stress (because there is least work to do against the external forces, and so most work available for breaking crystal bonds and propagating the fracture). In your model, the minimum compressive stress is actually the plane of the wall. There is nothing holding the elements of the wall from moving out of the plane of the wall. (This is, incidentally, why walls are built with buttresses and corners in them - they greatly stiffen the wall.) So, to correct this deficiency in your model, you need to fill in the spaces on either side of the wall to an arbitrary thickness with rock of comparable stiffness to that in the wall.
Now... you're applying your force to your selected piece of stone to model your small earthquake. And there is going to be a restraining force from the rock you're trying to displace with your moved "keystone". So...
What happens now?
"Thought experiments" are great. But they do need to relate to the system under study. Just because us geologists draw pictures of what is happening underground that we can pin onto a wall does not mean that a wall is the model we're thinking of.
"it has been tied to a number of smaller quakes, including the recent quake in England"
Two of the recent earthquakes in Britain. We've had 16 quakes recorded in the last 50 days, the strongest having a 3.5 magnitude and being a long, long away from the Lytham St Annes borehole. Britain is seismically quiet but not seismically silent. Unless you're specifically looking for these quakes, they don't stand out from the natural level of earth movements.
I guess I'm not sure how anyone is ruling out the possibility of a cumulative effect from the minor (2.8 and under) earthquakes, which we are being told can be caused by fracking, putting stress on the fault line. Is that really not possible?
Is it impossible? As a geologist I'd not say that it's impossible, but I don't think it is very likely.
The magnitude scale used for reporting earthquake intensity is a logarithmic scale. For a pair of quakes of Mw=5.6 (the "big" quake of a couple of weeks ago) and Mw=2.7 (an estimate for your "average" quake, given your 2.8 cut-off, and an unrealistically strong bias towards strong earthquakes in your sample), the relative strength is 10^[(3/2)*(5.6-2.7)] = 10^(3*2.9/2) = 10^4.35 = 22,387.
So... if you had on the order of 20,000 magnitude 2.7 earthquakes occur in an area, which all transmitted all their energy to the same particular point on a particular fault (incidentally leaving no spare energy to get to the surface to allow the 2.7 quake to be detected)... then it's not impossible. But I don't think it's particularly probable.
I know that I'm leaving aside the fact that the energy transmission would have to cover several kilometres vertically (see my comment somewhat up-thread), through formations of varying acoustic impedence (which results in reflection of some percentage of the acoustic energy towards the surface at each interface ; this is how seismic surveying works) ; that the low magnitude earthquakes would be scattered across an area (again, more distance for the energy to be transmitted, with more likely losses en route). I'm pretty sure there are lesser effects that I've not considered.
That's not "impossible" ; but I don't think it's likely to have happened.
(BTW, I am a geologist. And I do take my environmental responsibilities at work very seriously. That I don't think hydraulic fracturing is inherently an evil, baby-eating technology is because I do know what I'm talking about and I don't work in the media. And while I anticipate work in the shale gas industry, I haven't received any yet.)
That was my first thought too (speaking as someone who has been persuading my Boss to try to get us involved in more hydraulic fracturing work). The "big" quake had an epicentre at 5km, according to the USGS page, and while I don't know the typical depth of a shale gas well in Oklahoma, it's unlikely to be as deep as that because the whole point of doing fracturing is to be cheaper than conventional drilling. And a large part of the way of achieving that is going to be by keeping the drilling shallow - one or maybe two km.
Three vertical km is a long way for stresses to propagate, particularly in low-permeability formations.
Slashdot Mirror
We certainly don't want the sitting tenants either.
So your out-of-hand rejection of the OPERA result is stronger than the comments of the people that you cite in support of your position. That's not a very logical position. You may be right to reject "new physics" on the basis of the OPERA result - you may very well be right - but this datum isn't strong enough to claim that you're right by reasoning, rather than by luck.
FWIW, I'm sceptical of the OPERA results too, but I'm hopeful that they are right. What we do know is that there are big problems at the base of physics - GR being a classical theory of gravity and the Standard Model being a quantised model of the other forces, which suggests that something is wrong there.
Frosty pint? No thanks, I had enough last night and I've got a bit of a hangover. Besides, we've tickets for "Under Milk Wood" this afternoon, which manages to get through to even my philistine mind.
Well you would say that, wouldn't you?
I'm not disagreeing that TEPCO's various technical and financial calculations were incorrect. But that is a different thing to being "reckless", in both legal and moral senses.
(There are specific charges in the legal system that I work under that make a very clear distinction between actions that are "reckless" and ones that are ill-advised or poorly judged. For example, a case that a friend of mine in the trade union business was involved in a couple of years ago involved a building contractor one of whose workmen was injured when a trench collapsed. The contractor claimed that he'd been planning to shore the trench up when it got to a certain depth, and had made an error of calculation about what that depth should have been. The trade union (acting for it's injured member) asserted that, because there was no shoring material - boards and scaffolding poles - nor a plan for the shoring on site, then the contractor had been reckless - he'd completely ignored or not considered that risk. The judge found the contractor had indeed been recklessly negligent, and doubled the damages.)
What did Churchill say? Something about "two countries being so divided by sharing a common language"?
That depends entirely on where they choose to put the ice block.
I don't know about you, but I suspect that the Mongolians are just as capable of thinking about this as you are, and working to avoid such problems. (It's even just about possible that one of them reads Slashdot, and is striking their forehead and saying "Doh!" at this very moment.)
I can't think of a single example ever of a crime that has been perpetrated on a taxi driver or passenger by someone who was not also a passenger in the taxi. Plenty of cases of passengers robbing drivers ; no shortage of disputed fares ; but no people coming into a taxi to commit a crime against the driver or passenger who is already there.
For which case, CCTV or still imaging is appropriate, with no need for sound recording. (Some of the taxi companies in this city already use, and advertise, in-taxi photography. It's a straight commercial decision, reducing their insurance costs. And the bus company has CCTV fitted to all buses for the same reason.) For disputes over fares ... well the first thing a driver does after picking up a fare is radio to base "picked up from X to Y", which conversation is recorded at base. And on a number of occasions when scrotes have tried it on, they have found themselves on the receiving end of 4 or 5 other drivers performing a citizen arrest using reasonable force. And wheel wrenches.
Taxi crime isn't a major problem in this town.
I suppose I'd better RTFA now, but it's probably just some snotty nosed little jobsworth bawling to get attention and have his nappy changed. Oh, I see one link is to the Daily Flail. excuse me for not falling off the sofa in surprise.
Err, unless you're using a different meaning of "biggest", "flood", or "ever" to me and the dictionary . . .
Hang on - I read what you wrote as being "planet", not "plant", but "plant" makes sense as well.
On my mis-reading as "planet", the biggest flood waters to hit the planet ever were either the draining of Lake Missoula across the "scablands" of NW USA (see this summary and references therein) about 15,000 years ago, or one of the several re-fillings of the Mediterranean Sea basin after their desiccation in the Messinian Salinity Crisis (around 5 million years ago). There is an outside possibility that the Zechstein flood(s) 250-odd million years ago were bigger, but given the tectonics of the Mediterranean (a true ocean), I think the Messinian floods would have been volumetrically bigger. The flow through the Viking-Central graben series woulf have been pretty damned spectacular though.
OTOH, if you were actually referring to "the plant", then the history of the particular site is beyond me. However on general principles I'd expect any randomly selected part of the Japanese coastline to be subject to significant vertical motion on pretty short (10s of thousands of years) time scales. which should give pause for thought for locating things like nuclear waste repositories. But then again, all the volcanicity would rule Japan out for that sort of thing anyway.
That's still a touch too black-and-white ; the earthquake and tsunami were always possible, but they were not considered a sufficiently high probability to be designed against. Those probability assessments have no doubt been revised.
Other commentators are forgetting that there is a reason the reactors were built at sea-level : they need the cooling water. Putting them (say) 100m above sea level would increase the power requirements for pumping cooling water up to the plants, which would mean that you need more (or bigger) power stations. (Plus, of course, putting them on hillsides would increase the risk of ground instability in a large earthquake.)
The design of these structures was rational. Some of the design assumptions (e.g. the probability of earthquakes of magnitude X) may have been incorrect, with hindsight, but that is a different thing from being recklessly negligent.
More significantly ... when you've got a broken line (the typical excavator bucket going through a line type of accident), you're going to generate a lot of [pulse-pause-pulse-pause-pulse] signal trains from random contacts, and that is going to generate a flood of "calls" when there is an incident. When the EU mandated the use of "1-1-2" as a pan-European emergency services number they missed this possible failure mode, which has led to such incidents since then. "1-1-1" would be even more subject to the problem.
Not me, you stupid Septic. I was in the pub last night enjoying myself with a couple of other friends who also work in the oilfield (well, hell, this is a town with about 20% of the economy made up of oil service companies ; quelle surprise!), one of who comes from the Fylde and wanted to understand what the situation is. So I gave him my best opinion, because he asked politely and paid attention to what I was saying. And we arranged to maybe go hill-walking at the weekend too. Double-plus good.
I thought the site's tagline read "news", not "jokes"?
Yes I do work in the oil industry. And I'm not at work (though I will be in the office tomorrow). I do actually have opinions of my own. And I also do know a lot more about the process than you do.
That hydraulic fracturing can trigger earthquakes isn't an issue. That has been well demonstrated by the late 1960s Colorado waste disposal well - it's been literally a text book example since at the latest the late 1970s. I'm glad to see that the USA EPA have caught up on thirty-year-old text books - though given the US Govt's predilection for having shit in it's science textbooks, the case study may have escaped a generation or two of American geologists.
That some major earthquakes have fore-shocks is an observational fact. Whether that is relevant to the Oklahoma quake in particular is a different question. The USGS don't seem to think so.
Could the release of strain through the small fracturing-related earthquakes trigger the release of a larger earthquake? Well only a fool would say it was impossible, but up-thread I gave some energetics reasons why I doubt it's likely in this case. The USGS seem to think it's not the case too, and they know the area and it's stress fields much better than I care to find out (I'm much more concerned with the stress field of the Rumfiji Basin).
Anyway, you can go shove your fucking head up your cum-soaked arse if you think that I wrote that because I was paid to - I wrote it because I'm actually interested in the reality of what is going on. But since you seem to think that disagreement with you makes me automatically a shill, well fuck you. Stupid fucking American wanker, you deserve the government and corporate abuse you get.
Oh, incidentally, it is clear from the following that you do not understand one fucking thing about hydraulic fracturing :
Well done, fuckwit, you've just given a basic description of waterflood injection. Which is a completely different process. So, dumbfuck, go find yourself someone who is willing to spend their time explaining the difference to you. (Actually, we have a course in that in the training brochure. I think you'd get a little change out of $5000.)
4in diameter by 10in long? That would fit perfectly well in my briefcase. I might have to ditch the full-size laptop into hold-baggage, or carry a netbook instead of it, but I doubt that would be a serious problem. I might put a T-ring adaptor onto it and a couple of other lenses in the briefcase too, so it looks like a big lens and could be connected to the camera to prove it. It is a big lens, after all. Hand carry. Unload the laptop into it's separate tray (depending on airport regulations and phase of the Moon) and ask the security guard if they want the camera equipment to go through separately too? Shoes off today, or not? Already emptied all my pockets into the zip-up pockets of my jacket, so that goes into a tray. Watch off. Walk through the metal detector.
A telescope of that size is nothing but a large lens. You don't have to tell them that you've got a CCD detector in the hold baggage (or in the wife's hand-carry) along with the tripod. You don't have to fire up Maxsim on the netbook.
Oh, I'd try to find a recent copy of S&T or Astronomy now with an article about how to use a 4x10 scope to photograph the Transit. Keep that rolled up in the inside pocket of the jacket. Or carry a photo magazine with an article about shooting motor racing (or across the length of a sports field using a monster lens. But be prepared to "talk the talk."
Threats from Space?
Sorry to call you out Phil, but we don't know that. We are reasonably confident that there are none-such in the approximate plane of the ecliptic. Outside the plane of the ecliptic, we don't know that. And Phil knows his astronomy well enough to know that the orbital inclinations of long-period or sporadic comets are more-or-less randomly distributed. It's one of the main pieces of evidence that people have used for decades as grounds for talking about a more-or-less spherical "Oort Cloud" as opposed to a more toroidal "Kuiper Belt".
An impactor coming in from over one of the Sun's poles, looping around at perihelion and then coming barrelling down our throats ... would just about give us enough time to say a comprehensive "Stercus, stercus, stercus, moriturus sum!" before bending over and kissing (something) goodbye. And with the perhelion approach, we wouldn't know if it was going to be a hit or a miss until the fat lady was gargling and the amplifier was going up through 10.5. To mix several metaphors.
None of which quibbles decreases my enjoyment of the blog any!
The bombing target idea works for a lot of things. But what about the structure at 40.422906 Lat, 90.786896 Long ? It's about 200km west of the original cluster of artefacts. I say "about" because measuring the distance any more accurately is pointless. The damned thing is over 5km by 10km !
I really don't want to think about desiring to test bombs that can have a blast radius of several km or more. We have nukes in that range - do we need conventional weapons like that.
The high reflectivity is puzzling. Maybe a solar power installation? The site has cooling towers, what looks like liquid storage tanks, elongated buildings. Very odd.
Look at the X million tonnes of material you see on the highway ahead of you, heading east. And you think that may have an effect on the Earth's rotation?
What about the almost-exactly-X million tonnes moving west on the other side of the highway? That is going to have almost exactly the same effect but in the opposite direction.
The effects very largely cancel out.
Rebuttal style two : the wheels push against the road to push the vehicle forward. The vehicle needs to be pushed forward against friction from the air. The air doesn't all just pick up and follow the vehicle because of friction of the against the ground. That friction against the ground, when averaged out through eddies etc, acts in the same direction and to the same amount as the push of the wheels, but in the opposite sense. There is no net effect.
I remember in my physics homework being given thought experiments about inertia :
You can guess from the form of the problem that the two answers are different. The marks come from explaining your reasoning.
Actually, the Denver injection is a textbook case - and has been for at least 30 years. But the point should also be made that that case was the bulk disposal of hundreds of thousands of gallons of fluid over periods of years, which is orders of magnitude greater than a hydraulic fracturing job, which rarely lasts more than a few days of actual operations. (Rigging up and tearing down equipment may take much longer, as may drilling the well itself.)
What is your proposed mechanism, and how does it differ from the mechanisms that lead to the frequently-observed natural mineral-filled fractures in many rock formations? (You may not observe them ; I'm a geologist, and I observe more rock, more closely, than the large majority of people ; I see them very frequently.) What predictions do you make of observations that would differentiate your hypothesised mechanism from the existing model of natural fracturing by dewatering of sediment under diagenesis?
That's easily worked out. How many cubic metres of fluid were injected into the tubing at what pressure? That will give you the amount of work done. (Pressures will fluctuate somewhat, so you'd need to integrate the data not use one number for volume and a second for pressure. But that's trivial.) Compare the work done - the energy put into the system - by the high pressure fluid to the work done by the earthquake(s).
Do you care to bet which factor is many factors of ten larger? I know where I'd put my money (if I were a gambler).
The USGS certainly do make a lot of earthquake data available. I've been trying to get the corresponding data from the BGS, but their new historic data page has serious UI issues (under FireFox?).
Err, fracking is an INJECTION operation, not an extraction operation. Hydraulic fracturing prepares a well for gas (or oil) extraction. Then, the fracturing is finished, the well is flowed (to clean up and to check that the fracturing has achieved the production improvements desired), then suspended while the rig dismantled while a production flowline is installed.
You're getting confused between MD, TVD and TVDss (which is very common). That's Measured Depth (distance measured along the borehole, by measuring the lengths of pipe you're running into the hole) versus True Vertical Depth (the distance from the bottom of the hole perpendicularly to the altitude of the drilling rig's measurement point) versus True Vertical Depth sub-sea (which is TVD referenced to mean sea level, because ground level isn't level, and not all drilling rigs have their measurement point at the same height from the non-level ground ; for comparison between wells and across fields).
The hypocentre depth you give for the quake is 3.1 miles (converted from the 5km that the USGS cite? This is a science-tech website, not a historical-studies website.) either TVD or TVDss (probably TVDss).
The depth you give for the Woodford Shale is also most likely also a TVD or TVDss (what is the elevation of Oklahoma? That'll give you the difference between the two.), so you're saying that the target formation for the hydraulic fracturing operations is 1.36km (0.85 miles) above the hypocentre of the earthquake under discussion.
The 1.6 to 6.4km ("1-4 miles") you cite for a "typical" hydraulic fracturing well clearly implies, given your depths for the target formation, that the wells are "extended reach" or "horizontal" wells, where the main wellbore is at a considerable angle to the vertical, and you can have up to a 2000m of wellbore drilled parallel to the bedding ("horizontal", though if the target formation isn't horizontal, the terminology gets confusing!) at essentially the same TVD / TVDss. It is incredible that the well(s) would have penetrated significantly below the target formation, because that would increase costs for no commercial benefit. (There are engineering reasons to penetrate a small distance beyond the reservoir. For example, to allow long logging tools to pass the whole target.)
The popular press only understand one thing by "depth" ; in the real world (well, if you can call the oilfield that ; few insiders do!) there are several possible, reasonable, answers to "what depth is this hole?" To that extent, our in-house software contains a tool for converting between all 3 measures cited above, because the function is called on so often.
That's a poor analogy.
Firstly, the natural gas is not in "big holes in the ground" (which I assume you're modelling with your arch). It's in the interstices between rock grains, which themselves are supporting the main part of the weight of the overlying rocks (what we geologists call "matrix stress"). So, by removing the gas from a part of your wall (not that that's what is happening), a better analogy would be of a wall with one part having a strength of (say) 60MPa (your gas-filled rock) and 70MPa (for the bulk of the wall.
Now your model is better, but still badly wrong. In fracturing (whether it be hydraulic, explosive, or whatever) the fracture propagation will be in a direction perpendicular to your minimum compressive stress (because there is least work to do against the external forces, and so most work available for breaking crystal bonds and propagating the fracture). In your model, the minimum compressive stress is actually the plane of the wall. There is nothing holding the elements of the wall from moving out of the plane of the wall. (This is, incidentally, why walls are built with buttresses and corners in them - they greatly stiffen the wall.) So, to correct this deficiency in your model, you need to fill in the spaces on either side of the wall to an arbitrary thickness with rock of comparable stiffness to that in the wall.
Now ... you're applying your force to your selected piece of stone to model your small earthquake. And there is going to be a restraining force from the rock you're trying to displace with your moved "keystone". So ...
What happens now?
"Thought experiments" are great. But they do need to relate to the system under study. Just because us geologists draw pictures of what is happening underground that we can pin onto a wall does not mean that a wall is the model we're thinking of.
Two of the recent earthquakes in Britain. We've had 16 quakes recorded in the last 50 days, the strongest having a 3.5 magnitude and being a long, long away from the Lytham St Annes borehole. Britain is seismically quiet but not seismically silent. Unless you're specifically looking for these quakes, they don't stand out from the natural level of earth movements.
Is it impossible? As a geologist I'd not say that it's impossible, but I don't think it is very likely.
The magnitude scale used for reporting earthquake intensity is a logarithmic scale. For a pair of quakes of Mw=5.6 (the "big" quake of a couple of weeks ago) and Mw=2.7 (an estimate for your "average" quake, given your 2.8 cut-off, and an unrealistically strong bias towards strong earthquakes in your sample), the relative strength is 10^[(3/2)*(5.6-2.7)] = 10^(3*2.9/2) = 10^4.35 = 22,387.
So ... if you had on the order of 20,000 magnitude 2.7 earthquakes occur in an area, which all transmitted all their energy to the same particular point on a particular fault (incidentally leaving no spare energy to get to the surface to allow the 2.7 quake to be detected) ... then it's not impossible. But I don't think it's particularly probable.
I know that I'm leaving aside the fact that the energy transmission would have to cover several kilometres vertically (see my comment somewhat up-thread), through formations of varying acoustic impedence (which results in reflection of some percentage of the acoustic energy towards the surface at each interface ; this is how seismic surveying works) ; that the low magnitude earthquakes would be scattered across an area (again, more distance for the energy to be transmitted, with more likely losses en route). I'm pretty sure there are lesser effects that I've not considered.
That's not "impossible" ; but I don't think it's likely to have happened.
(BTW, I am a geologist. And I do take my environmental responsibilities at work very seriously. That I don't think hydraulic fracturing is inherently an evil, baby-eating technology is because I do know what I'm talking about and I don't work in the media. And while I anticipate work in the shale gas industry, I haven't received any yet.)
Three vertical km is a long way for stresses to propagate, particularly in low-permeability formations.
That's not how hydraulic fracturing works, nor any other type of hydrocarbon extraction.