Showing posts with label fracking. Show all posts
Showing posts with label fracking. Show all posts

Wednesday, 4 February 2015

Prof Smythe: "Well" out of date


It would appear that I have a new admirer. Imitation being the sincerest form of flattery, I consider myself very flattered that Professor Smythe has created a blog in my honour, going so far as to name it "Frackland" in reflection of my own small contribution to the national shale gas debate.

Prof Smythe has featured previously on this blog, firstly when I pointed out errors in his critique of Cuadrilla's Balcombe operations, and subsequently to document his contretemps with the Geol. Soc. and Glasgow University.

In his original critique of Cuadrilla's operations at Balcombe, Prof Smythe proved himself to be ignorant of modern drilling technologies. Sadly, it seems that Prof Smythe has doubled down on his errors in a new presentation, which, in a comment on his blog, he claims "show[s] that it is James Verdon, not I, who misunderstands the technology of drilling".

In his latest piece, Prof Smythe admits to learning about geosteering and LWD at the Dart Airth CBM planning inquiry, and grudgingly concedes that one of my principal criticisms was, in fact, accurate: "It is correct that I did not at that time know about the gamma-ray geosteering technique." I would add that listening to a submission at a planning inquiry does not make anyone an expert in anything.
 
It is interesting that Prof Smythe refers to a "gamma ray" geosteering technique. I don't actually refer specifically to gamma-ray logging at any point in my original comments. There is a reason for this: there is a huge range of LWD measurements that can be made to measure the properties of the rocks through which a well is being drilled.

The motivation for this is severalfold - in addition to the real-time aspect of LWD, in horizontal wells a "well tractor" is required to pull wireline logging tools (the traditional method of well logging, done once the well had been drilled) along the horizontal section of the well, which can be time consuming and expensive. LWD obviates this need, so as a result in the last 20 years much effort has been put into developing LWD tools that can match traditional wireline tools both in terms of the different petrophysical measurement techniques, and the quality of the measurements.

If Prof Smythe thinks that LWD is limited to a non-directional gamma-ray measurement then he is still spectacularly uninformed as to the state of modern drilling technology.

Almost every traditional wireline logging tool is now available as a LWD equivalent. This might include measuring the electrical resistivity (which is particularly sensitive to whether the rock is full of oil/gas (high resistivity) or salt water (low resistivity)), the porosity, the bulk density, and the acoustic properties of the formation, in addition to its gamma-ray levels. The latest technologies can even tell you the colour of the rock you are drilling through (organic-rich rocks tend to have a dark colour), and microimaging even takes images of the rock as you go!

Equally importantly, these measurements are not taken uni-directionally. Modern LWD tools take measurements at many angles to the well bore. This enables an operator to identify the dip of the beds through which he is drilling, as demonstrated in the image below, taken from a Schlumberger Oilfield Review paper. Note that this SOR is from 1996, which gives an indication of how out-of-date Prof Smythe's comments are. Prof Smythe (and the interested reader, of course) would do well to peruse the latest offerings from the various oilfield service providers, such as this from Weatherford or this from Schlumberger.

So, how does all this tech help an operator stay in zone while drilling a horizontal well. In most cases, an operator will have prior geological data from logs run in vertical wells (such as Cuadrilla will have had from Conoco's drilling of the first Balcombe well in 1986). They will have identified marker beds from this log data, characterising the petrophysical properties of each different layer (the resistivity, porosity, density, acoustic properties, the microimages etc.). These marker beds, along with the dip information, are then used to guide the horizontal wellbore and stay in formation. If a fault is intersected, the well will find itself in a different geological layer. The operator can determine which layer this is by comparing the LWD data with pre-existing logs and, in combination with the dip data, determine where the well must be steered in order to return to the formation.

Now, if a fault is encountered that has substantial offset, it may not be possible (or economic) to steer the well back to the target formation, and the well must be abandoned. And of course it's better if an operator has 3D seismic data to help plan their wells, and to ensure that their LWD matches the 3D seismic data. I make this point in my original post, and I expect that as operators move from exploratory to production phases, we will see more 3D seismic data collected. However, LWD data alone is usually sufficient to keep a well on target, even if faults are encountered.

Importantly, however, the proof is in the pudding.

One of Prof Smythe's principal conclusions was that keeping the well within the 30m thick target layer would be a "near impossibility", "all-but impossible", and "the drilling will therefore almost certainly transgress into the Kimmeridge Clay, either above and/or below the micrite (the target layer)." Indeed, Prof Smythe goes so far as to claim that Cuadrilla will intentionally drill out of formation in order to collect samples of Kimmeridge Clay with a mind to future fracking at Balcombe, and makes the claim that Cuadrilla's activities at Balcombe were little more than a "cover story" for future unconventional work.

Prof Smythe maintains that "[his] criticism of Cuadrilla in 2013 was and remains substantially correct". However, in September 2013, Cuadrilla announced the results of their Balcombe well, and that "using geo-steering technology, the entire 1700ft was successfully drilled within the target limestone".

Now, Prof Smythe might claim that Cuadrilla are still deceiving us. If they are, it would be a odd thing to do, given that all well log data becomes publicly available after a short confidentiality period, so they'd know that they'd soon be found out.

He also makes the unsubstantiated accusation that Cuadrilla may actually have encountered a fault, and that they had been forced to stop drilling as a result:
"We do not know why the horizontal well stopped at 518 m (1700 ft). For all we know, Cuadrilla may have encountered a fault."   
This seems very unlikely. If Prof Smythe were more familiar with the full history of the Balcombe site, he would have been aware that Cuadrilla's planning consent for the site expired on the 30th September 2013. By this date they were required to have removed all of their drilling and other kit from the site. The two images below show the drilling equipment on site, and the condition to which Cuadrilla had to return the site by the 30th September.


Cuadrilla completed their drilling on the 23rd September. Prof Smythe claims that Cuadrilla stopped drilling because they had encountered a fault. I would suggest that the far more likely explanation is that they only had 7 days left before their planning consent expired, and wanted to give themselves enough time to run whatever tests they wanted to do, before removing all their kit from the site, and probably leaving a bit of spare time as well in case protestor activities caused further delays (as happened earlier in their operations).

In his original criticism, Prof Smythe made strong conclusions ("near-impossibility", "all-but impossible") , and accused an operator of intentional deceit, which should not be done lightly. I would suggest that when an "expert" claims that something is a "near-impossibility" and "all-but impossible", but then that thing happens, then those claims do not "remain substantially correct", as Prof Smythe claims. In fact, I'd think it would be considered rather embarrassing, and would draw the status of said "expert" into question. Perhaps this is why the Geol Soc asked Prof Smythe to cease referring to himself as a Chartered Geologist.




Friday, 24 October 2014

Sigmas and Sharpshooters


Today's paper is a recent report published in the journal "Earth's Future" looking at methane emissions from shale gas operations in the USA. As you'd expect from a paper that is critical about shale gas exploration, it has received extensive media coverage.

However, the paper falls short in a couple of really important ways, which I'll discuss below. Sadly, it provides a few handy lessons about how not to go about doing science. The first issue is falling foul of the Texas Sharpshooter Fallacy, the second is failing to use the proper measures to ensure the result is statistically significant.

Firstly, the Texas Sharpshooter Fallacy. The parable is of a hopeless Texan gunman looking to prove to the world his martial prowess. So he takes aim with his pistol at the side of a barn, and blasts away. Once he has done shooting, he notices that by chance some of his shots happen to have hit close together. He then paints on a target with its bullseye at that point, before inviting the neighbours over to admire the results of his sharpshooting skills.

More technically, this fallacy describes a situation where certain clusters of data are cherry picked from a larger population because they happen to fit your hypothesis, ignoring all the cases that would disprove the hypothesis.

So how does this fallacy apply to the paper in question? The image below shows the methane measurements for 2006-2008 (the "before" case) and 2009-2011 (the "after" case) presented in the paper:



It's clear that methane has gone up substantially all across the USA in this period. There are many sources of methane emissions, both naturally occurring (bogs, swamps etc) and man made (farms, coal mines, conventional gas wells, and shale wells). What is noticeable is that while there are places where there is shale gas activity and high methane concentrations, there are plenty of places with no oil and gas activity that have seen methane levels rise, while in other places there is shale gas activity but methane levels that are not particularly relevant.

For example, Nebraska saw substantial increases in methane, yet in 2010 there were only 2 drilling rigs in the entire state. It's a similar story in, for example, Iowa (0 drilling rigs), Illinois (2 drilling rigs) and Indiana (3 drilling rigs). In contrast, Arkansas, home of the Fayetteville shale with 39 active rigs in 2010, and Northwestern Louisiana, home of the Haynesville shale with 135 active rigs in 2010, have noticeably low methane concentrations.

There are many different shale gas/oil plays across the USA. It is apparent that methane concentrations also vary across the USA. It is therefore inevitable that, just by chance, some areas of high methane will correlate with areas of shale production. Our sharpshooters have drawn their targets around 3 such areas (the black boxes in the above image) and declared themselves to be expert marksmen. Not good science.

We can see the same effect within the individual study areas as well. The following image shows the change in methane levels for Texas from 2006-2008 to 2009-2011:



During this time, there was active drilling and unconventional hydrocarbon production from the West Texas Permian Basin, the Haynesville Shale and the Eagle Ford Shale. Neither the Permian nor the Haynesville show anything out of the ordinary, while there are other areas with no active drilling that have seen substantial methane increases. It's a similar story for the Marcellus in Pennslyvania, shown below: there are places with drilling that have high methane levels, but also places with drilling that have low measurements, and places with high measurements that do not have drilling.



The second issue is one of error bars and confidence intervals. With any scientific measurement, there is an error bar marking the interval over which we can be confident the result is accurate. Typically, confidence limits of 95% are used - if it is said that a measurement is 5 ± 1.5 at a 95% level, then we can be 95% confident that the true value lies somewhere between 3.5 and 6.5.

The authors of this paper complete their analysis for the Bakken and Eagle Ford shales, concluding that methane emissions have increased by 990 ± 650 ktCH4/yr and 530 ± 330 ktCH4/yr in each case.

What is unusual, however, is the limits they have chosen for their error bars. These are set to the 1-σ level, or one standard deviation. This corresponds to a confidence interval of only 68%, meaning there is a 1-in-3 chance that the computed value was arrived at by chance.

Scientists generally use the 2-sigma level as an error bound - corresponding to a 95% confidence level in the result (which still means that the measured observations could have occurred by pure chance 1 time in 20). For really important experiments, scientists will require even higher confidence bounds, like the 5-sigma bound for the Higgs Boson discovery, which means a 1 in 3,500,000 chance of a spurious result.

I've not often seen a confidence level of 1-sigma being used in peer reviewed science, given the implication of a 1-in-3 chance of being a spurious result. Instead, let us double their confidence levels to the 2-sigma limit (95%) more normally expected as a minimum for scientific findings. We then find the results have become 990 ± 1300 ktCH4/yr and 530 ± 660 ktCH4/yr. In both cases the error bars have become larger than the values themselves. We cannot even be sure whether rates of methane emissions have increased or decreased, since the lower error bars at the 95% level fall below zero.

In short, even with the Texas-Sharpshooting described above, the authors have not managed to produce statistically robust evidence to back up their claims. However, it's given me a chance to discuss both the Texas Sharpshooter Fallacy (which is also a common problem in attempts to forecast earthquakes) and the importance of error bars, which I am sure both scientific and non-scientific readers alike will have enjoyed.




Wednesday, 22 October 2014

Europe's Geological Surveys Make Joint Statement on Shale Gas

After a meeting in Copenhagen, the North Atlantic Group of the European Geological Surveys released a statement on shale gas and fracking. More info is available here.

This group is made up of the Geological Surveys of the UK, Germany, Ireland, Holland, Norway, Iceland and Denmark, so it represents most of Europe's geological expertise. Make no mistake, these guys are experts.

Below are a choice selection of quotes both from their Copenhagen statement, as well as comments from the President of Germany's Federal Institute for Geosciences (the BGR) in a press release. The press release is in German, so I have used google to translate as best I can. Apologies to any German speakers who spot any mis-translations, but the general gist of the statements should be clear to all.

Firstly from the Copenhagen Statement:

"The Survey Directors are concerned that frequent misleading media messages regarding exploration and exploitation of raw materials and geo-energy have the potential to obscure scientific results and conclusions, and may ultimately lead to poor decisions for Society."
"The Survey Directors emphasise that their Surveys hold the majority of key sub-surface data for their Nations. They are thus best placed to objectively and independently inform decision makers, on shale and other georesource estimation exercises, and on some of the potential environmental risks of the operations."

"Particular concern was expressed that the role of the national Geological Survey may be bypassed, resulting in the submission of poorly formulated geoscientific advice to governments."
The press release from the BGR was even more explicit:
"The European Geological Surveys of the North Atlantic area, which include the Federal Institute for Geosciences and Natural Resources (BGR), fear in the face of misleading reports in the media about the exploration and extraction of raw materials negative socio-political consequences."
"Often dangers are evoked where there are none. When fracking for production of natural gas there are widespread fears in the population, most of which are unfounded from geoscientific perspective."
"Since the early 1960s, more than 320 fracking measures in conventional natural gas production have been carried out in Lower Saxony. The technique used here is similar to the method for the development of shale gas resources. In these past operations by fracking there has not been a single incident in which the environment has been damaged. When critics speak in connection with fracking as an uncontrollable high-risk technology, this is just wrong under scientific criteria." (my emphasis)
I think these comments will be worth remembering as the shale gas debate rumbles on over the coming months.


Saturday, 11 October 2014

Advertising Complaints in Australia

A few months ago I blogged about Frack Free Somerset (FFS)'s decision not to challenge a complaint about their promotional material made to the Advertising Standards Agency (ASA). Their leaflet contained numerous errors and misleading statements. Because FFS agreed to remove their material and cease using it, rather than to attempt to offer a rebuttal, the ASA never carried out an investigation.

There are obvious parallels to the complaint made to the ASA over Cuadrilla's publicity material, and over an advert placed by the self-styled "Frack-Master" Chris Faulkner.

We in the UK are not the only country to provide an advertising regulator, and in this post I will report on a decision reached by the Publishing Advertisers Bureau in Australia.

Before I do so, however, I want to comment on the situation we now find ourselves in, where advertising standards agencies are finding themselves having to make judgements on what are, in some cases, quite complicated and technical issues, with very little understanding of the subject matter. I very much doubt that anyone at the ASA has any familiarity with oil and gas operations and/or regulation.

While I am sure that the ASA are used to dealing with complaints in subject areas they are not familiar with, I would suggest that this debate is very different to determining whether or not a new brand of shampoo really makes your hair feel 10 times silkier. Yet as an authoritative body it is inevitable that their pronouncements are taken very seriously indeed, when the more I think about it, the less reason I see to do so. Frack-Master Chris Faulkner summed the situation up: "the ASA has been both judge and jury in this case. They appear to have become unqualified experts in fracking and interpreting the complex issues surrounding fracking in the UK".

However, today's blog is about a decision in Australia. The opposition group Frack Free Geraldton (FFG), with support of the Conservation Council of Western Australia (CCWA), published an advert in the local rag, the Geraldton Guardian. The Australian Petroleum Production and Exploration Association (APPEA) submitted a compliant regarding the advert, which appears to have been upheld. In each case, the statements made by FFG and CCWA were found to be misleading and deceptive.

The statements, and the reasons for the findings, are discussed below.

"Shale fracking, the process of extracting gas by using toxic chemicals to crack deep rocks, can turn our water into a dangerous chemical cocktail"

It was found that this statement gives a misleading impression of the fracturing process, because it gives the impression that most of the fracking fluid is composed of toxic chemicals. It was found that "The statement that 'toxic chemicals' are used to crack deep rocks creates the impression that toxic chemicals 'alone', certainly not in such small percentage quantities are used to frack", which is not the case: frack fluid is 99% water, with only a small amount of additive, most or all of which is not toxic.

The statement finds that "to an ordinary reasonable reader the words of the advertisement and the accompanying illustration together create the impression that the amount of 'toxic chemical' used is a much greater concentration that is in fact the case", which is a misleading and deceptive exaggeration.

With regards to turning water into "a dangerous chemical cocktail", it was found that while there are risks posed by hydraulic fracturing, "the consensus of scientific data suggests that there have been no cases internationally of hydraulic shale gas fracturing inadvertently breaching a water source and thereby causing contamination", and that "a combination of research from around the world shows us that the risks are low".

Moreover, in their response to the complaint, CCWA "have not produced any evidence that hydraulic fracking fluid has in the course of any hydraulic shale gas fracking process permeated a fresh water aquifer. Its contentions are against the scientific literature".

"Research in the US has found that 6% of fracking wells leak into ground water in the first year"

Anyone who is familiar with this blog will already know why this statement is misleading. It is a topic I have discussed extensively. The 6% statistics refer to the number of wells that have some kind of casing or cement issue in one of the casing strings. However, wells have several casing strings to separate the production zone from any sensitive groundwater supplies. This means that a well with an issue in one casing string will not be spewing hydrocarbons into the environment. It's a belt-and-braces type approach.

A paper by King and King in 2013 (SPE) is instructive in this regard:
For US wells, while individual barrier failures (containment maintained and no pollution indicated) in a specific well group may range from very low to several percent (depending on geographical area, operator, era, well type and maintenance quality), actual well integrity failures are very rare. Well integrity failure is where all barriers fail and a leak is possible. True well integrity failure rates are two to three orders of magnitude lower than single barrier failure rates.
In their response, the CCWA admit that their statement "is not materially correct", and it is therefore found to be "misleading and deceptive".

This is a point I've been making for some time, so it's good to see that even environmental bodies know that it is not correct to say that 6% (or 30% or 50% or whatever) of wells are leaking, even if they do still insist on claiming this in their promotional material.



"Once our water is contaminated, it will be forever" 

This statement ignores the abundant evidence that while any contamination incident is bad, the damage is rarely permanent: wells that do leak can be repaired, spills can be remediated. For example, Considine et al. (2013) examine the environmental impacts from drilling in Pennsylvania, and find 25 incidents that they deem to be "serious". However, they find that in all but 6 cases the impacts had already been remediated satisfactorily. The APPEA provided similar examples of remediation in their supporting evidence for their complaint.

In contrast, "the contentions put forward by CCWA in support of this statement in its submission dated 22 August 2014 are without any independent scientific support. They are unsupported assertions." 

As a result, it was found that "the statement that once contaminated water will forever be contaminated is not supported by contemporary scientific views and is misleading and deceptive." 


For anyone interested in the original complaint, the CCWA rebuttal and the final decision, the documents are available below.

The original APPEA complaint is here.
The CCWA response is here.
Further APPEA comments are here.
The final decision is here.



Monday, 6 October 2014

The CIEH and me: full discussion


A few months ago, the Chartered Institute of Environmental Health (CIEH) released a report into the impacts of hydraulic fracturing and shale gas extraction in the UK. You can read the original report here. Of particular concern was that the report's lead author had already taken a leading role in protests outside of unconventional gas drilling sites in the UK: hardly the best place to start if you are looking for a balanced report.

In my opinion, the quality of the report was very very poor, ranking as little more than scaremongering and with little understanding of the oil/gas extraction process. I was infuriated enough to write a rather outspoken blog post criticising the report, which some readers might remember.

In the days following the report's publication, I ordered my thoughts a little from my original post, and sent a more moderate and thoughtful criticism to the CIEH. The CIEH provided an initial response to my criticisms.

Incidentally, the CIEH made their response public, without actually stating my criticisms alongside their response (or informing me that they had done so). I can only assume that they weren't comfortable seeing their response alongside my original criticisms.

This wouldn't surprise me given the weakness of the response. In some places their is direct and/or tacit admission of error, while in others the authors manage to contradict themselves. I was originally prepared to let sleeping dogs lie and "agree to disagree", especially since I had a busy fieldwork schedule over the summer. However, the quality of the response was so poor that I couldn't help but write a further comment to the CIEH. I have not now received a response to those comments (nor do I expect to, if I'm honest), so I have decided to make public the full extent of our discussion for all to see.

I should add a warning, these are fairly lengthly documents, but hopefully make for an interesting read if you have a few minutes to spare and a cup of tea to hand.

My first critique of the CIEH report is here.

The CIEH response to my critique is here.

My comments on the CIEH response is here.








Thursday, 25 September 2014

Landmark shale gas study shows no groundwater problems


One of the difficulties in the current shale gas debate is that good data is hard to come by. Operators collect lots of data from around their sites, including water sampling to test for pollution, and geophysical monitoring to track where the fractures went during stimulation. However, this data is often considered commercially sensitive, so it rarely sees the light of day.

A government-sponsored project would be very useful, because it would provide a test-bed for an extensive monitoring program. All data could then be made public, and the claims of all those involved in the shale gas debate openly tested.

This is exactly what has been happened in the USA, with the final report released this week. The US National Energy Technology Lab (NETL) sponsored a monitoring program at a hydraulic fracking operation in Greene County, Pennsylvania. The monitoring program consisted of 2 parts: microseismic monitoring to track the fractures created by the stimulation, and geochemical sampling in overlying layers to test whether any contamination has occurred. Most importantly, because the data is publicly available, it's a great opportunity to talk through the anatomy of hydraulic stimulation.

The first stage of shale gas extraction is to drill horizontal wells through which the fracking will be done. The figure below shows a map of the lateral wells drilled. Those in the yellow box were the 6 wells that made up the NETL study.



Sunday, 21 September 2014

New study shows leaky wells, not fracking, is causing methane leakage


This week's most newsworthy study examines methane contamination in wells in Pennsylvania and Texas, linking them with drilling activities. It is authored by the same Duke group who have published on this topic a number of times now.

In the new study, the authors analyse the geochemistry of methane and groundwater around shale gas wells. As well as measuring the geochemistry of the methane, they measure other geochemical variables such as noble gas isotope ratios and salinities, in order to get a better handle of what might be leading to the elevated methane levels.

They find that in some cases the evidence points to a deep source of methane that has migrated relatively rapidly, with little contact with the rock layers that lie in between shallow aquifers and the deep layers in which fracking is conducted. The most obvious conclusion to make is that methane is not getting into shallow layers through cracks and fractures in the rock, but that methane migration through faulty well bores to the surface is a possibility.

The study has, for obvious reasons, garnered a lot of publicity. However, the more I thought about it, the less newsworthy the study becomes. In actual fact, I think it tells us little that we didn't already know.

We already know that faulty cement and/or casing can allow methane migration from depth. We already know that in a handful of cases in Pennsylvania, poor working practice from certain operators has lead to cement/casing problems - these companies have been prosecuted and fined by the Pennsylvania Department of Environmental Protection. So it's hardly surprising that the authors of the study were able to find cases where the geochemical evidence pointed to this issue.

Wednesday, 17 September 2014

New Life-Cycle Assessment for UK Shale Gas


A new life cycle assessment for UK shale gas has been released by researchers from the University of Manchester. This study considers a range of potential environmental impacts. Most significantly, it compares shale gas extraction against a host of other energy technologies, including conventional gas, coal, nuclear power and renewables. 

This sort of comparison is very important, because when it comes to energy sources, we have to choose how our energy mix should be balanced. All sources of energy have impacts, and we can't say no to all of them. 

Equally significant is the fact that the study doesn't just consider the global warming impact of the various technologies (the global warming potential, or GWP), but a whole host of environmental factors , including the use of abiotic resources (rare earth elements etc), acidification, eutrophication, freshwater, marine, terrestrial and human toxicity, and ozone depletion. 

Before I get into the details of the study, the first figure I'll borrow is the one that compares the global warming potential (GWP), according to the various previous studies: 


Sunday, 14 September 2014

My Fracking Answers

Update 21.9.2014: I thought it unlikely that DECC would provide a response to MyFrackingQuestions, which is why I wrote this post. It seems that I was wrong, DECC have now provided an official response.

The latest shale gas publicity stunt, which follows on from the damp squib that was TalkFracking, is MyFrackingQuestions, a website that allows users to put together a customised email to be sent to Matthew Hancock, the new Minister of State for Energy.

Sadly, I suspect that Mr Hancock will be too busy to get round to providing detailed answers. To make up for this, I have provided some My Fracking Answers. The MFQ questions, divided in a topic-by-topic basis, are in italics, followed by My Fracking Answers:

Tuesday, 22 July 2014

Another day, another shale gas report

Update (23.7.2014): It transpires that Gwen Harrison, the report's lead author, was recently an election candidate for the Green Party, which has explicitly stated its opposition to fracking in all circumstance. Moreover, judging by recent tweets it seemed she was involved blockading trucks at IGas's Barton Moss site.

Of course, there's nothing wrong with joining political parties nor joining protests. However, it makes a mockery of the claim that the report is "impartial" and "evidence-based", and goes a long way to explaining the report's contents.


Original Article:
Another day, another shale gas report to dissect. Today's offering comes to you courtesy of Scientists for Global Responsibility and the Chartered Institute of Environmental Health. The report claims to take an "impartial, evidence based approach". It does anything but, so once again it falls to me to point out the more egregious errors.

The best place to start is on the very first page, which shows two schematic images of the fracking process. In both cases the scale of images is such that the depth of the well is smaller than the height of the drilling rig, implying that fracking is taking place at a depth of less than 100m, rather than the actual depth, typically 2 - 3km.

Similar images are provided on page 4, and nowhere are images with the correct scales shown. The images are so out of scale that the "impartial, evidence based" claim immediately cannot be taken seriously. The moment you see an image like this, you know what to expect.

To the non-expert, the degree of the error in these images might not be immediately apparent, so I did a little photoshopping to demonstrate. Imagine if you were reading a report on whether it was safe for commercial airliners to overfly cities at altitude, and on the first page of the report was the following image, I don't think it would be taken that seriously by air safety experts:


Wednesday, 9 July 2014

German Success...?


A big week for Germany in the news. And no, I'm not talking about 7 - 1!

New rules for hydraulic fracturing have been announced in Germany. This has been widely reported as "Germany bans fracking", but the devil may be in the detail - indeed some groups opposed to fracking have referred to it as a "fracking enabling law". This is because it appears that fracking will be allowed at depths below 3,000m, and "where drinking water is not in danger". It is not clear whether this means in areas where no potable groundwater is present, and/or "if the liquid being used cannot contaminate water".

The laws are due to be further discussed in the Autumn, where hopefully some of these ambiguities will be addressed.

Fracking is not new to Germany. Most of Germany's existing natural gas production, from Lower Saxony in the north of the country, requires hydraulic stimulation to be economic. These are not shale rocks, but "tight sandstones", with low permeability requiring fracturing to improve flow rates. The figure below shows the number of frack-jobs performed in Germany over the last few decades.

It's not clear whether the proposed ban would include these existing reservoirs.

Wednesday, 25 June 2014

"5 Fracking Myths Busted" - Busted


A new anti-fracking initiative, Talk Fracking, is currently touring the country. Their website has a thin veneer of balance, claiming to seek an "open debate" on fracking, but you don’t have to scratch too deeply to see their true motivation.

I’ll consider one particular video in detail, which claims to have “busted” all of the reasons to support shale development in the UK.

Before addressing the substance of the video, however, I will address the style. Talk Fracking say that they want to open up a balanced debate on fracking. Yet the video has this strange, childish, mildly insulting caricature of an “industry representative” to present the pro-fracking case. If you’re looking for a balanced debate, putting up insulting straw-man caricatures of your opponents is hardly the best way to start.


Thursday, 29 May 2014

New paper: Estimates of error in micro-earthquake magnitude estimation


With excellent timing, on the same day as the new BGS report into the shale oil potential of the Weald Basin, a new paper, written by two co-workers at Bristol Uni and myself, has been released in Geophysical Prospecting. In it, we examine the uncertainties in estimates of event magnitude made on small earthquakes.

This paper is significant for shale gas extraction in the wake of DECC's traffic light system (TLS) proposal for fracking operations. Under the TLS, operational decisions during the fracking process must be taken on events as small as magnitude 0.0 (the amber level), with complete cessation of activities for events larger than magnitude 0.5.

As most people are aware, a magnitude 0 event is very small, at the limit of what can be detected using conventional seismographs (see our efforts at Balcombe, for example). Expensive downhole microseismic monitoring systems are required to robustly detect smaller magnitudes.

The TLS pre-supposes that earthquake magnitudes at this low level can be accurately determined. The purpose of the TLS was to provide a simple-to-understand system to re-assure the public. Uncertainties in event magnitude estimation could undermine this, generating more controversy, not less.

We show in our paper that event magnitude estimations at these low levels can be very uncertain: you can get different answers depending on what methods you use and assumptions you make. It doesn't take too much imagination to think of a scenario where one group reporting on a fracking operation concludes that an induced earthquake was just below the TLS threshold, but another group using a different method finds that the earthquake did exceed it. The current debate over shale gas extraction is febrile enough as it is, can you imagine the recrimination and the confusion that such an eventuality would generate?

Monday, 12 May 2014

Frack Free Somerset and the ASA


Earlier this year I was contacted by a local Somerset resident. He'd attended a meeting hosted by Frack Free Somerset, and had concerns about the accuracy of the promotional materials they'd used.

The resident was intending to submit a complaint to the ASA regarding these materials, and got in touch with me for some advice about some technical details, which I was happy to provide.

The ASA began their investigation, but the issue has now been resolved as FFS have agreed to withdraw the offending literature without rebuttal (Informally Resolved Cases, Date 7th May 2014). By doing so, there is no requirement for formal investigation.

As far as I see it, this represents tacit acceptance that all of the original complaints are valid. However, by withdrawing rather than making a challenge, FFS have managed to avoid the media fanfare associated with a full ASA investigation.      

There is an obvious comparison here with Cuadrilla's ASA investigation. Of the 18 complaints made by anti-fracking groups, only 6 were upheld by the ASA. In contrast, it would appear that FFS are not even prepared to try and defend the contents of their own promotional materials.

I have re-posted the original FFS brochure here, and the complaint from the local Somerset resident here.




The complaint cites a number of supplementary materials. These are as follows. Attachments 1a-e were data sheets taken at random from Barnett shale wells on the FracFocus website, summarised in attachment 1f. Attachment 2 was DECC's document about fracking and water. Attachment 3 summarised cancer incident rates in Barnett Shale counties (Denton, Johnson, Parker, Tarrant, Wise) taken from http://statecancerprofiles.cancer.gov. Attachment 4 detailed key health indicators for Denton County taken from Mickley and Blake. Attachment 5 was the DECC document on shale gas regulations and safety. Attachment 6 shows US natural gas prices and shale gas extraction rates (easily available just about anywhere), and Attachment 7 compares coal and CCGT power station efficiencies, Figure 6 in this EIA report.

Saturday, 19 April 2014

Recent Earthquakes in Ohio


The Associated Press reports several earthquakes in eastern Ohio that have been linked to shale gas extraction. If true, this represents the 4th time that hydraulic stimulation in shales has been associated with seismic activity. This follows Preese Hall, Lancashire, the Horn River Basin, Canada, and Garvin County Oklahoma.

Note that it is important to differentiate between earthquakes triggered by hydraulic stimulation (i.e. fracking) and those triggered by underground disposal of large volumes of waste fluids, which is not being considered in the UK. It is the underground waste disposal wells that have been attributed to the increase in mid-continental seismicity seen in the USA.

Attributing cause and affect with respect to earthquake triggering is a difficult challenge. Frohlich and Davis (1993) came up with a series of 7 questions that are still commonly used to attribute "induced" earthquakes. These are:

  1. Are these events the first known earthquakes of this character in the region?
  2. Is there a clear temporal correlation between injection and seismicity?
  3. Are epicentres near wells (within 5km)?
  4. Do some earthquakes occur at or near injection depths?
  5. If not, are there geologic structures that may channel flow to earthquake sites?
  6. Are changes in fluid pressure at the well toe sufficient to induce seismic activity?
  7. Are changes in fluid pressure at hypo central locations sufficient to encourage seismicity? 
However, without good quality seismic data, these questions can be difficult to answer.

Friday, 28 March 2014

Image of the day: First Frack!

This is a photo taken of the first hydraulic fracture stimulation operation, performed in Kansas in 1947 by Stanolind Oil.


Fracking has been around for many decades. However, it has evolved significantly during this time. In 1947, Stanolind used 1,000 gallons of napalm-thickend gasoline. Modern stimulations in shale reservoirs might use 1,000,000 gallons of "slick-water" - 99% water with chemical additives such as guar gum, polyacrylimide and hydrochloric acid.

Thursday, 27 March 2014

Guest Post: Frack Free Somerset Meeting, 22nd March


Dr Doug Robinson, now retired, but until recently a Senior Lecturer at Bristol University, attended a public meeting held by Frack Free Somerset last week. Following his visit, Dr Robinson contacted me to discuss the experience, and to outline his concerns about the group. His comments follow:
Notices posted by the frack free Somerset group for a meeting in Wookey Hole village about fracking “heading our way” attracted my attention being a retired geologist and local resident. I went along assuming it was a bona fide group raising rational concerns about unconventional gas recovery, and that there would be an opportunity to have an informed discussion on the pros and cons of the issues involved. At the introduction it was stated that the group had no political or other agenda and wanted to provide a balanced account of the pros and cons of the fracking controversy and that in the discussion, views and comment allied to both sides of the argument were welcome. 
The hour-long film produced by the group was said to present to provide a balanced and true view of the debate on unconventional gas development. The film, however, was largely based on opposition to the exploitation of unconventional gas, and of little more than a propaganda style repeating many of the unsubstantiated and well-known scare stories that have already been widely aired in the press and online. The film did use various cuts from interviews with professional Earth scientists, and also showed and gave quotes from the 2012 Royal Society report on “Shale gas extraction in the UK: a review of hydraulic fracturing” (available at http://royalsociety.org/policy/projects/shale-gas-extraction/report/), attempting to show engagement with scientific issues. These examples were however of negative points, and didn’t attempt to use such sources to present a scientific analysis of the process. Two examples can be used to demonstrate this point:

Wednesday, 26 March 2014

Image of the day: Hydraulic fracture height growth.


This figure is from a paper by Fisher and Warpinski (2012). The wiggles at the bottom show the maximum heights of hydraulic fractures, as imaged by microseismic data. The upper blue lines shows the maximum depths of drinking-water aquifers in the areas. 

This data shows clear separation of thousands of feet between drinking water sources and the rocks where hydraulic fracturing is being performed. This shows that hydraulic fracturing itself are extremely unlikely to be a cause of contamination - if water is impacted it is most likely to be from either spills at the surface or issues with wellbore integrity.

   

Tuesday, 18 March 2014

Comments on the RSPB shale gas report


Today's post centers on a "new" report from the RSPB on the impacts of shale extraction in the UK. I say new, because it's really just a rehashing of a few existing reports (more on this below).

Before I get into the meat of things, there's one particular (not shale related) aspect I would like to address, because having been through it numerous times, and not always successfully, it is a subject very dear to my heart. The reports claims to be "peer reviewed" by the Center for Ecology and Hydrology. To my mind this is not a peer reviewed document. Peer review does not consist of handing your work to a friend to read over (though I would recommend to any young scientist that they do so BEFORE submitting for peer review).

Peer review implies an independent editorial body to oversee the process. Moreover, like the scientific process itself, peer review also implies the possibility of failure - that the reviewer has the option of saying that a paper is incorrect/unsuitable/makes unsupported conclusions and therefore should not be published. None of the above seems to be the case here, so I do not consider this report to be peer reviewed. That the authors are prepared to claim otherwise shows a worrying lack of respect for the process. Perhaps to non scientists this seems a little pedantic, but I'm sure anyone that has gone through the peer review process will understand that it should not be taken lightly, nor should the mantle of "peer-reviewed" be attached to things that are not. 

Thursday, 27 February 2014

Is Exxon's CEO a NIMBY?


Can you guess who is the latest star of the anti-fracking movement? No, it's not someone glued to something up at Barton Moss, but Rex Tillerson, CEO of Exxon. According to the Wall Street Journal, Tillerson has joined a lawsuit trying to prevent fracking in his local area. This would be something of a surprise, seeing as Exxon subsidiary XTO Energy is a major player in the US shale industry.

As you'd expect, the anti-fracking twittersphere has been set alight once more with this news. After all, if Exxon's CEO won't put up with fracking in his back yard, why should the rest of us?

However, is Mr Tillerson really against fracking? As so often seems to be the case, it pays to dig a little deeper. It seems that Mr Tillerson's opposition is not to shale gas extraction in his area, but to the construction of a large water tower next to his ranch. Moreover, while the water company involved has supplied water to fracking companies in the past, it has not done so since 2009: the primary use for the water tower is to supply residential demand.