Showing posts with label Hydraulic Fractionation. Show all posts
Showing posts with label Hydraulic Fractionation. Show all posts

Friday, 4 October 2013

Environment America reports on fracking in the USA.

Fracking, or Hydraulic Fracturing, is a process by which water, sand and chemicals are forced into buried sediments in order to shock them into releasing trapped hydrocarbons, which can then be extracted for commercial use. This has proved highly controversial with environmentalists, who accuse the process of causing Earthquakes, polluting groundwater, and using large amounts of fresh water.

Environment America is a federation of state-based, citizen-funded environmental advocacy organizations, which both engages in grassroots activities such as letter writing campaigns and organizing public meetings and more academic projects such as commissioning research into environmental issues. 

On Thursday 3 October 2013 the group published a report entitled Fracking by Numbers, which examines the environmental impact of the industry across the US, and makes a number of recommendations as to how both state and federal governments should regulate the industry. The report was authored by Elizabeth Ridlington of the Frontier Group (a US environmental thinktank) and John Rumpler of the Environment America Research & Policy Center.

Fracking is known to be taking place in 17 US states, with permits for over 800 000 wells having been granted since 2005 (how many of these have or will be developed is less clear). The industry is keen to expand into a number of other states.

Plays (areas where hydrocarbons are thought or known to accumulate) currently being exploited by the hydraulic fracturing industry, and those currently being targeted for future exploitation. Riddlington & Rumpler (2013).

Hydraulic fracturing has been widely associated with the contamination of both ground and drinking water. This can occur in a number of ways, including the direct leaking or spillage of chemicals used in the fracking process, well blowouts (in which drilling operations encounter unexpected pockets of pressurized gas, typically resulting in an explosion at the wellhead), migration of methane or other material from the reserve to aquifers and long term migration of wastewater at or beneath the surface (water used in the fracking is not typically returnable to normal use, having been contaminated both by chemicals added to it during the fracking process and from within the well). 743 such incidents have been reported in New Mexico, 340 in Colorado and 161 in Pennsylvania.

The process of pumping used water into strata deep below the surface, typically beds from which liquids have previously been extracted is considered particularly hazardous, due to the potential failure of subsurface structures which can result in contaminated water migrating to aquifers unseen, and the risk of changing the pressure within, and therefore mechanical properties of, these beds, which has been linked to an upsurge in seismic activity in a number of places. A number of incidents of the failure of water storage plants at the surface are also sighted, as well as several of frackers deliberately (and illegally) discharging contaminated water into the environment.

An open waste pit storing contaminated water from a hydraulic fracturing operation near Summit, Pennsylvania. The use of such pits is prohibited in most industries in the US, but fracking is currently exempt from such legislation. Riddlington & Rumpler (2013).


Fracking has also been linked to the creation of water shortages in a number of areas. The industry uses a large volumes of water and, as noted above,  this is seldom suitable for other purposes once it has been used. This creates a conflict of interest with other water users, which has left fames and communities without water in Texas and New Mexico. There have also been reports of frackers illegally draining water from natural sources which (in theory) were subject to legal protection.

The industry has also been widely associated with atmospheric pollution, both via the venting of gasses being extracted and fumes from chemicals used in the process. A number of volatile aromatic compounds have been recorded at or around sites where hydraulic fracturing occurs. Workers at sites have also been found to be found to be suffering from silicosis (miners lung), a disease in which silica particles (sand), which the body cannot expel, build up in the lungs, inhibiting breathing.

A number of health clinics in Pennsylvania have also reported patients showing signs of exposure to toxic substances, who refused to leave names and paid in cash. Public health officials suspect these may be employees in the hydraulic fracturing industry afraid to leave details in case it affects their jobs.

The industry is also associated with air pollution on a wider scale, including the production of large volumes of nitrogen oxides, which are a significant factor in smog formation, and significant emissions of greenhouse gasses. Natural gas (methane) has widely been promoted as a 'bridge fuel', something to use until better renewable sources become available which is less polluting than oil or coal. However methane is a powerful greenhouse, and studies have suggested that significant amounts of the gas extracted by hydraulic fracturing is lost to the atmosphere, one study in Utah indicating over 11% of the total gas was lost in this way, making the process considerably more polluting than coal, even before losses later in the supply chain, and the effects of carbon dioxide produced by burning the gas are taken into account.

Methane storage tanks, which can be a source of leeks adding to the industries environmental footprint. Riddlington & Rumpler (2013).

Fracking also has a notable effect on the landscape, with the process requiring a large area be flattened and cleared of vegetation to permit access of drilling equipment, as well as an extensive network of supporting roads etc., often in areas that have either been agricultural or completely unused by humans. This has obvious aesthetic implications, but also creates severe problems for wildlife, leading habitat fragmentation and reducing the area available to bird and mammal species that need large territories for successful reproduction. Companies are known to be seeking to expand their activities into a number of US National Parks, as well as other significant and iconic wilderness areas.

Wells and roads on the Jonah Gas Field in Wyoming. Riddlington & Rumpler (2013).

The industry also places considerable costs on local communities, which may not receive any benefits in return. The industry uses large vehicles, that will have a heavy impact on local roads that may not have been built to handle such traffic, and in many areas the arrival of the industry has been linked to a dramatic upsurge in traffic accidents. The arrival of large numbers of temporary workers in an area can place considerable strain on areas such as housing, often requiring increased investment to support the needs of local populations. There is also a danger of the industry leaving post-extraction environmental costs to local communities; this is in theory illegal, but in practice the companies involved can be liquidated in a number of ways, leaving shareholders with profits and local agencies with the cleanup bill.

The report makes a number of recommendations for both state and federal governments.

At state level the report recommends that state governments ban the process, or where it is already in use impose an immediate moratorium. Where states are not willing to do this they should allow cities, towns and counties to do so. States should also specifically ban the disposal of waste from the industry within their borders, to avoid becoming dumping grounds for waste created elsewhere.

At federal level it recommends the closing of a number of loopholes in environmental legislation that exempt the industry from regulations that other industries are bound by, particularly those relating to the disposal of hazardous waste, the protection of water supplies, the protection of national parks and other wilderness areas and the storage of wastewater in open pits. It also recommends that tighter financial assurance regulations be put in place, to prevent companies leaving cleanup costs to local communities.

See also Secret fracking off the coast of CaliforniaThe British Geological Survey reports on Shale Gasses in the Bowland-Hodder UnitGeological Society of London to host a public meeting on Shale Gas extractionReport recommends Fracking should be allowed to continue in the UK and Fracking linked to earthquakes in Lancashire, northeast England.

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Monday, 23 September 2013

Magnitude 2.7 Earthquake in Okfuskee County, Oklahoma.

The United States Geological Survey recorded a Magnitude 2.7 Earthquake at a depth of 5.0 km, roughly 1 km to the southeast of the Oknoname Reservoir in Okfuskee County, Oklahoma, slightly after 3.05 pm local time (slightly after 8.05 pm GMT) on Sunday 22 September 2013. This is not a large quake, and is unlikely to have caused any damage or casualties, but is was probably felt locally.

The approximate location of the 22 September 2013 Okfuskee County Earthquake. Google Maps.

Oklahoma is naturally prone to Earthquakes, particularly in the southwest of the state, near the Meers Fault Zone, but since 2009 has suffered a sharp increase in the number of small quakes in the central and northeast parts of the state. While most of these quakes have been quite small, a few have been large enough to potentially cause problems, and any unexplained increase in seismic activity is a cause for concern. 

In a paper published in the journal Geology on 26 March 2013, a team of geologists led by Katie Keranen of the ConocoPhillips School of Geology and Geophysics at the University of Oklahoma linked one of the largest of these quakes, a Magnitude 5.7 event in November 2011 which caused damage locally and was felt across 17 states, to the practice of pumping liquids (usually brine) into injection wells, which is common in the hydrocarbons industry and used to displace oil or gas, which can then be extracted from nearby extraction wells (where this is done in bursts at pressure to intentionally break up rock it is called hydraulic fracturing, or fracking). Significantly they suggested that the practice could lead to quakes years or even decades after the actual injection.

Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) you can report it to the USGS here.


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Magnitude 2.9 Earthquake in Payne County Oklahoma.

The United States Geological Survey recorded a Magnitude 2.9 Earthquake at a depth of 5.0 km roughly 2 km to the northeast of the town of Ripley in Payne County, Oklahoma, slightly after 11.35 pm local time on Saturday 21 September 2013 (slightly after 4.35 am on Sunday 22 September GMT). This is not a large quake, and is highly unlikely to have caused any damage or injuries, though a number of people reported feeling it in the north of Payne County.

The approximate location of the 21 September 2013 Payne County Earthquake. Google Maps.

Oklahoma is naturally prone to Earthquakes, particularly in the southwest of the state, near the Meers Fault Zone, but since 2009 has suffered a sharp increase in the number of small quakes in the central and northeast parts of the state. While most of these quakes have been quite small, a few have been large enough to potentially cause problems, and any unexplained increase in seismic activity is a cause for concern. 

In a paper published in the journal Geology on 26 March 2013, a team of geologists led by Katie Keranen of the ConocoPhillips School of Geology and Geophysics at the University of Oklahoma linked one of the largest of these quakes, a Magnitude 5.7 event in November 2011 which caused damage locally and was felt across 17 states, to the practice of pumping liquids (usually brine) into injection wells, which is common in the hydrocarbons industry and used to displace oil or gas, which can then be extracted from nearby extraction wells (where this is done in bursts at pressure to intentionally break up rock it is called hydraulic fracturing, or fracking). Significantly they suggested that the practice could lead to quakes years or even decades after the actual injection.

Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) you can report it to the USGS here.


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Monday, 16 September 2013

Magnitude 2.5 Earthquake in Van Buren County, Arkansas.

The United States Geological Survey recorded a Magnitude 2.5 Earthquake at a depth of 900 m in southern Van Buren County, Arkansas, slightly after 0.35 am local time (slightly after 5.35 am GMT) on Sunday 15 September 2013. This is a fairly small quake, and is unlikely to have caused any damage or injuries, but it was felt as far away as Conway, 35 km to the south.

The approximate location of the 15 September 2013 Arkansas Earthquake. Google Maps.

Central Arkansas has been suffering an ongoing series of Earthquakes that began in August 2010, and which collectively are referred to as the Guy-Greenbrier Earthquake Swarm. This has been linked to the use of Hydraulic Fracturing (Fracking) in the area, not directly by the process itself (which involves water, sand and chemicals are forced into buried sediments at considerable pressure in order to shock them into releasing trapped hydrocarbons, is often linked to Earthquakes), but by the practice of pumping waste water from the process into deep wells. 

The process was banned in the area in 2011, following recommendations from the United States Geological Survey, and two oil companies operating in the region, Chesapeake Energy and BHP Billiton reached an out of court settlement with local residents who claimed their homes had been affected by quakes caused by the process in August 2013.

Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) you can report it to the USGS here.


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Tuesday, 20 August 2013

British MP arrested at Sussex anti-fracking demo.

Caroline Lucas, the Green Party MP for Brighton Pavilion was arrested at a demonstration against the activities of the hydrocarbons exploration company Cuadrilla Resources in the Sussex village of Balcombe on Monday 19 August 2013, along with her son and a number of other protestors. Ms Lucas has subsequently been bailed and has yet to learn weather she will face criminal charges. The number of protestors at the site has been growing steadily since operations began at the site on 25 July, with over a thousand people reportedly present at the weekend. The protestors are concerned that the company may use hydraulic fracturing at the site, a technology which has been associated with a range of environmental problems, ranging from water pollution to small Earthquakes, and which Cuadrilla has become strongly associated with in the eyes of the British public after it was forced to suspend operations at at a site in Lancashire following to seismic activity.

Green Party MP being led away by police in Balcombe on Monday 19 August 2013. Rex Features.

Caudrilla have stated that the operation will involve the drilling of a 914 m well and 762 m horizontal borehole, and will not involve any fracking, which would require additional permission from West Sussex County Council. They have also stated that they are following all regulations put in place by the Department of Energy and Climate Change, the Environment Agency, the Health and Safety Executive and West Sussex County Council.

However protestors have expressed doubts that the group would be drilling exploratory wells without the intention of further operations, and have suggested that the current legal structure around such drilling operations favors wealthy companies over local communities. Many have also complained that the policing operation was disproportionate, and that they are a symptom of the state intervening to protect a 'wealthy few' against a local community standing up for itself.

Support for the protest has grown rapidly, both in Sussex and across the UK, following a string of heavy handed actions by Sussex Police and a refusal to meet with from government ministers and local Conservative Party MP Francis Maude, indeed several senior figures within the party have openly expressed support for the drilling operation and opposition to the protest, taking part in what would usually be considered the Conservative Party's heartland, claiming that hydraulic fractioning is vital to the UK's future fuel economy, but refusing to enter into debate on the matter or discuss possible alternatives.

This has led to a number of protests at other sites, with protestors occupying the UK headquarters of Caudrilla at Lichfield in Staffordshire and those of public relations company Bell Pottinger, who have been representing Caudrilla, in central London.


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Sunday, 4 August 2013

Secret fracking off the coast of California.

It emerged this week that hydraulic fracturing (fracking) has been in regular use in the oil fields of the Santa Barbara Channel off the coast of California since the late 1990s. There has been a moratorium on new drill leases in the area since a spill in 1969 which released over 11 million liters of crude oil into the ocean off the coast of Santa Barbara, covering over 60 km of beaches in oil and killing millions of seabirds, an even that led to the drafting of federal clean water laws.

Existing oil field leases and drilling platforms off the coast of southern California. San Francisco Chronicle.

Following a Freedom of Information request by The Associated Press, the U.S. Environmental Protection Agency has admitted that it has permitted the use of fracking to stimulate the production of additional oil from wells with declining productivity in areas where new wells would not have been permitted, apparently without the knowledge of officials from the State of California, who do not have juristritrcion over exploration projects more than three miles (4.8 km) from the shore, though they could potentially oppose permits if they feel water quality is likely to be threatened.

Hydraulic fracturing involves pumping water, sand and chemicals at high pressures into gas and oil bearing sediment, particularly non-porous strata such as shales and mudstones, in oder to break up the rocks and release the hydrocarbons. However it has been linked to raised seismic activity, and to pollution incidents deriving from both the release of hydrocarbons and chemicals used in the process, contentious issues in southern California. To make matters worse many chemicals that have been banned from use in the process on land in the US are not similarly banned from use off-shore, despite some being known to be harmful to marine organisms, and others never having been tested for use in this environment.


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Friday, 26 July 2013

Anti-fracking protestors arrested at Sussex demo.

Sixteen protestors have been arrested at a protest against exploratory drilling at Balcombe in West Sussex by Caudrilla Resources, currently the only company involved in hydraulic fracturing (fracking) in the UK. The company was granted a permit to cary out drilling at the site by West Sussex County Council and began operations on Thursday 25 July 2013, leading to protests by around 250 local residents and environmental activists. The protests continued through the night and following day, leading to complaints from Caudrilla that the protestors were inhibiting access to the site and causing alarm to workers. Around a hundred officers from Sussex Police moved in on the protestors at about 3.20 pm on Friday 26 July, arresting sixteen and moving others from the site.

A protestor being arrested at the Balcombe protest. Protestors and local witnesses have stated that none of those arrested resisted the police, which Sussex Police have not contested. Frack Free Sussex

Caudrilla have stated that the operation will involve the drilling of a 914 m well and 762 m horizontal borehole, and will not involve any fracking, which would require additional permission from West Sussex County Council. They have also stated that they are following all regulations put in place by the Department of Energy and Climate Change, the Environment Agency, the Health and Safety Executive and West Sussex County Council.

However protestors have expressed doubts that the group would be drilling exploratory wells without the intention of further operations, and have suggested that the current legal structure around such drilling operations favors wealthy companies over local communities. Many have also complained that the policing operation was disproportionate, and that they are a symptom of the state intervening to protect a 'wealthy few' against a local community standing up for itself.

Sussex Police have stated that they support the right to protest, but also have a duty to facilitate contractors carrying out their business.

The approximate location of the Balcombe drilling site and protests. Google Maps.

Fracking, or Hydraulic Fracturing, is a process by which water, sand and chemicals are forced into buried sediments in order to shock them into releasing trapped hydrocarbons, which can then be extracted for commercial use. This has proved highly controversial with environmentalists, who accuse the process of causing Earthquakes, polluting groundwater, and using large amounts of fresh water. The process uses high pressure blasts in order to produce shock waves, which will hopefully cause the release of hydrocarbons. Shock waves in buried strata are, in layman's terms, Earthquakes, so an increase in Earthquakes in areas where Fracking is being practiced is not surprising. Environmentalists have also raised concerns that making large amounts of new hydrocarbons available will lead to further rises in atmospheric CO₂, with consequences for the global climate.


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Thursday, 27 June 2013

The British Geological Survey reports on Shale Gasses in the Bowland-Hodder Unit.

Shale gasses have become an economically important source of hydrocarbons in the early twenty-first century, as other reserves have run low and exploration companies have begun to look for new supplies of energy. In conventional oil and gas reserves the hydrocarbons are usually trapped within pore spaces in discrete pocket, usually of sandstone or porous limestones, which can be drilled into to release the hydrocarbons. In shales the gasses are found throughout larger, essentially impermeable, units, and need to be released proactively. This can be done through a process known as Hydraulic Fracturing, or Fracking, in which water, sand and chemicals are blasted into the rock at high pressure, causing it to shatter and release the gas. This has proved to be highly lucrative in some parts of the world, notably the US where it has fueled a small hydrocarbons boom, but has also caused great alarm among environmentalists, who linked the process to small Earthquakes and pollution of important aquifers, as well as raising concerns that making large amounts of new hydrocarbons available will lead to further rises in atmospheric CO₂, with consequences for the global climate.

As in other countries, there is growing interest in developing shale gasses as a source of fuel in the UK, though the extent of potentially exploitable reserves is largely a matter of speculation. One of the geological units that has been of particular interest is the Bowland-Hodder Carboniferous Shales, which underlie much of northern England.  With this in mind the Department of Enregy and Climate Change and British Geological Survey have produced a report into possible gas reserves within the Bowland Shales, published on 27 June 2013. This report does not make any judgement on the ethics of shale gas exploitation, or wether it would be possible to extract these gasses at all, but simply to assess the extent of the reserves in order to facilitate further discussion. In the absence of such published information governments have sometimes naively (or possibly dishonestly) underestimated the value of mineral reserves within their territories and granted concessions to companies at far less than their actual worth.

Location of the DECC/BGS study area in central Britain, together with prospective areas for shale gas, currently licensed acreage and selected urban areas. Other shale gas and shale oil plays may exist. DECC/BGS (2013).

Natural gasses are formed from the 'cooking' of biological material (principally plant matter) in deeply buried sediments. When  biological material is sufficiently heated and pressurized, then volatile compounds are forced off as gas. In porous sediments this will typically escape from its point of origin, rising up until it becomes trapped at a high point in the porous rock, with impermeable sediments, such as clays, above. However when such material is trapped within clays or shales (finely laminated clays) it is unable to escape, and remains in situ. In order for gasses to develop in such sediments they need to be deeply buried, but they may subsequently be uplifted and found closer to the surface.

The Bowland Shales and underlying Hodder Mudstones were laid down in shallow marine basins in the early Carboniferous (347-318 million years ago), a time when Britain was close to the equator and sea-levels were rising and falling with the spread and shrinkage of ice caps. These deposits are not shale and/or mudstone throughout, rather there are layers of limestone within, formed as reefs which formed close to the shore spread back and forth with the rising and lowering level of the sea. These deposits have been deeply buried since the Carboniferous (which ended around 299 million years ago), and for the most part are still at some depth, though in places they have been uplifted and outcrop at the surface.

Shales from the Hodder Mudstone Formation outcropping on the flank of Ashnott High, Bowland Basin, Lancashire. Nicholas Riley in DECC/BGS (2013).

In order to assess the amount of gas trapped in these deposits, it was necessary to asses the amount of organic material within the sediment (estimated as typically 1-3%, but rising to 8% in places), as well as the thickness of the deposits. As these deposits are for the most part very deeply buried (the top of the unit is 4753 m bellow sea level at its deepest), they were only directly accessed by boreholes in a limited number of places, with much of the study being based upon geophysical data, principally from seismic studies and gravitational data. 

The depth of the top of the Bowland-Hodder Unit below sea-level. Note that in places this is a negative figure; the deposits are above sea-level but still underground. DECC/BGS (2013).

Previous estimates of the thickness of the Bowland-Hodder Unit have ranged from 2500 m to 4000 m. The DECC/BGS study estimates it to be around 3575 m at its thickness, thinning down to zero in places.  

The thickness of the Bowland Hodder Unit; it was not possible to measure map the unit in Derbyshire. DECC/BGS (2013).

However the volume of the unit cannot be correlated absolutely to the amount of gas it will contain. In order for organic material to have been converted to gas it will have to have been buried deeply enough for the process to have occurred, considered to be sediments that have been buried to a depth of 2900 m for the purposes of this study (even if they have subsequently been uplifted or exposed). This is referred to as the 'gas window', and can be mapped as a discrete horizon in itself.

The depth bellow modern ground level of the 'gas window' in the Bowland-Hodder Unit. Below this level the unit can be expected to contain shale gas, above it this is not likely to be the case. DECC/BGS (2013).

Thus the maps of the depth and thickness of the Bowland-Hodder unit do not give a reasonable estimate of the distribution of gas-bearing sediments in the study area. Furthermore sediments at depths of less than 5000 ft (1500 m) are not considered to be workable by hydraulic fractionation; the pressures in the rock are too low for the method to work.

Thickness and distribution of shales of the lower Bowland-Hodder unit that are within the gas window and at a depth greater than 5000 ft (1500 m). DECC/BGS (2013).

Thickness and distribution of shales of the upper Bowland-Hodder unit that are within the gas window and at a depth greater than 5000 ft (1500 m). DECC/BGS (2013).

The study produced three estimates of the total volume of gas in the rock (not the same as the total recoverable gas), referred to as the low, central and high estimates. The low estimate predicts a total volume of 4.6 trillion m³ of gas in the lower unit and 18.6 trillion m³ of gas in the upper unit, for a total of 23.3 trillion m³ of gas. The central estimate predicts a total volume of 7.5 trillion m³ of gas in the lower unit and 30.2 trillion m³ of gas in the upper unit, for a total of 37.6 trillion m³ of gas. The high estimate predicts a total volume of 12.7 trillion m³ of gas in the lower unit and 51.9 trillion m³ of gas in the upper unit, for a total of 64.6 trillion m³ of gas. 


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Saturday, 26 May 2012

Geological Society of London to host a public meeting on Shale Gas extraction.

Shale Gas is naturally occurring gas trapped within shale (sine grained sedimentary rocks, typically mostly clay) formations. This is harder, and more expensive, to extract than other forms of Natural Gas, but is becoming increasingly attractive to hydrocarbons companies as other sources of gas start to dwindle. Typically Shale Gas is extracted using a technique called Hydraulic Fracturing, or Fracking, which involves blasting water, sand and chemicals into shale beds at high pressure in order to fracture the rocks and release the Gas.

Diagram of a Hydraulic Fractioning operation. geology.com

Shale Gas extraction has expanded rapidly in the US in recent years, and is expected to produce half of all the Natural Gas extracted in the US by the year 2020. It has, however, proved to be extremely unpopular with environmental groups, both within the US and in other countries, to the extent that some countries have altogether banned the practice.

There are four principle objections to Shale Gas extraction. One of these is that Natural Gas is a hydrocarbon, and potentially contributes to Global Warming; this is no different to the objections to the extraction of Natural Gas from other sources, excepting that extracting the gas from shale significantly increases the available reserves. The remaining objections are with the Fracking process, and are therefore specific to Shale Gas extraction.

Firstly the process causes Earthquakes. This is not in dispute, though the scale of the quakes the process can cause is hotly disputed between environmentalists and the industry. An Earthquake is shaking in the ground, regardless of the source; a large truck driving past your house does not merely feel like its causing an Earthquake, it actually is. Blasting water, sand and chemicals into buried sediments with the intention of fracturing the rock will certainly cause Earthquakes (if it did not it would not work). 

Industry experts do not expect the process to produce quakes larger than a magnitude of 1 on the Richter Scale, but areas where Fracking occurs in the US have seen an unexpected increase in quake activity, with some quakes exceeding magnitude 3. Since the Richter Scale is logarithmic this represents quakes more than a hundred times as large as predicted, leading the industry to claim that any connection is impossible, but not able to provide an alternative explanation (in some cases this is further confused by the employment of lobbyists who do not understand the process and who will offer blanket denials for even the most minor of quakes). In the UK the process has been linked to two small quakes near an experimental Fracking operation at Preese Hall in Lancashire, leading to a halt in operations.

Secondly the process has been linked to the contamination of aquifers; the chemicals used in the process are potentially toxic, and people do not like the idea of these getting into drinking water. Again industry models do not predict that the chemicals could escape the targeted deposits into other strata, but the chemicals have been found in the aquifers. A report into the industry in the US was unable to confidently say that the process had caused the contamination, but only because the chemical containment at the surface was so poor that contamination from ground-level sources could not be ruled out.

Thirdly the process uses large amounts of water, a matter of some concern in more arid parts of the US, where the industry is suspected of the using water that could be used for other purposes, notably agriculture.

In the UK a report commissioned by the Department of Energy and Climate Change was published last month (April 2012), recommending that the process should be allowed in the UK, subject to very tight environmental regulation, bringing the process back into the public eye.

On 18 June 2012 the Geological Society of London is hosting a public meeting to discuss Shale Gas Extraction, at Burlington House in London. The meeting will not seek to address whether the process should be used in the UK, but will seek to explain the geological science behind the process, and whether it can be undertaken safely. The meeting is not aimed at geologists, but rather at elected representatives (politicians), local and central government officials, regulators, NGOs, representatives of other industries likely to be affected (such as water companies) and other interested parties.

The location of Burlington House.

The meeting will be addressed by Mike Stephenson of the British Geological Survey, who will discuss the nature and distribution of shale gas reserves in the UK, Richard Davies, of Durham University, who will discuss the Hydraulic Fractionation process, Peter Styles of Keele University (one of the authors of the Department of Energy and Climate Change report), who will discuss the safety of the process with regard to induced seismicity (i.e. causing Earthquakes). The meeting will also discuss the potential effects on groundwater, and the uses of water in the industry, as well as the regulatory framework for the industry in the UK, though the speakers on these subjects are yet to be confirmed.

The layout of Burlington House.


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Tuesday, 17 April 2012

Report recommends Fracking should be allowed to continue in the UK.

Fracking, or Hydraulic Fracturing, is a process by which water, sand and chemicals are forced into buried sediments in order to shock them into releasing trapped hydrocarbons, which can then be extracted for commercial use. This has proved highly controversial with environmentalists, who accuse the process of causing Earthquakes, polluting groundwater, and using large amounts of fresh water.

To date the UK has been host to only a single, experimental, fracking project, at Preese Hall near Blackpool in Lancashire. Operations were stopped at Preese Hall in 2011, after two small Earthquakes in April and May were connected to activities there.

The Preese Hall well site in Lancashire. The Australian.

This week a report commissioned by the Department of Energy and Climate Change was published, entitled 'Preese Hall Shale Gas Fracturing: Review and Recommendations for Induced Seismic Mitigation'. This was written by Peter Styles of the Department of Geography, Geology and the Environment at Keele University, Brian Baptie of the British Geological Survey and Christopher Green, director of GFrac Technologies, and concludes that fracking should be allowed to continue in the UK, as long as certain conditions are met.

The team recognize that the Preese Hall operations were the most likely cause of the Lancashire Earthquakes, and that there was a high likelyhood of continued operations in the same area causing further quakes. In addition the report found that the quakes caused deformation in the structure of the well - deformation that could lead to chemicals used in the process leaking into other strata than the ones intended.

An earlier report in the US found that chemicals from a fracking operation there had entered aquifers, but was unable to say whether this was due to the process itself, or due to spillages at ground level. This was widely cited as vindication of the process, which is odd since clearing the fracking element of the operation could only be achieved by claiming blundering incompetence in another part of the process, but spin often seems to overtake logic in debates over fracking (and the energy industry in general).

Fracking undoubtably does cause Earthquakes. An Earthquake is shaking in the ground, a large truck driving past your house doesn't just feel like an Earthquake, it is an Earthquake. Blasting pressurized water and sand into buried rocks in the hope of causing them to fracture will definitely cause Earthquakes (if it didn't there wouldn't be any fracturing, and the process would not work). Unfortunately extraction companies involved in hydraulic fracturing employ lobbyists and press spokesmen who do not always appreciate this, and who may not be concerned too much if the truth gets slightly obscured in getting their side of the story across, leading to some confusion on this point.

What should be being discussed is the scale of Earthquakes that can be caused by fracking. Engineers in the industry have repeatedly estimated that the process should not be causing quakes greater than magmitude 1.0 on the Richter Scale, but several areas in the US where fracking operations are underway have suffered increases in seismic activity with quakes in excess of 3.0 being reported. The Richter Scale is logarithmic, so a magnitude 3.0 quake is 100 times as powerful as a 1.0 quake. Nobody has been able to explain how fracking could be causing quakes this much larger than predicted, leading the industry to claim that the increases are co-incidental, and that without a proposed mechanism they cannot be held responsible. In this light the UK report, which directly links fracking to two Earthquakes measuring 1.5 and 2.3 on the Richter Scale is a blow to the industry.

The report recommends that all hyrdraulic fractioning operations in the UK should be carefully monitored for seismic activity, at the operators expense, and any operation shown to have caused a quake in excess of 0.5 on the Richter Scale should be halted immediately. They furthermore note that it is highly unlikely that a fracking operation in the UK could ever cause a quake in excess of 3.0 on the Richter Scale, and that a quake on that scale could not cause any serious damage.

While this has widely been reported as a green-light for the fracking industry in the UK, it potentially places a considerable additional burden upon them, since the expense of installing seismic monitors would add significantly to the cost of the operation, and the possibility of being forced to close down at any point would make investing in any such operation highly risky (an industry that cannot explain how it causes larger quakes would probably be unable to prevent or predict this).

Environmental groups in the UK have expressed a great deal of concern at the report, even though it recommends tight regulation of the industry. This is not surprising, as the current UK government has a track record of friendliness towards the hydrocarbons industry (Business Secretary Vince Cable is a former oil-man), and of opposing environmental regulation of any sort. In addition Chancellor of the Exchequer George Osborne recently announced plans to encourage the building of gas-fired power stations in the UK, which suggests that fracking operations targeting natural gas are likely to be welcomed. In the light of this there is clearly a concern that the report could be used to justify resumption and expansion of fracking operations in the UK, without putting into place the recommended regulatory measures.

The operators of the Preese Hall site, Cuadrilla Resources, are certainly keen to resume operations. They estimate that the Lancashire field contains about 11.3 trillion m³ of natural gas; enough to power the UK for over 50 years. However the British Geological Survey estimate the field contains much less gas, 0.13 trillion m³, and that only 5-10% of this will be recoverable - enough to power the UK for 21 days. This big a disparity in estimates shows a surprising degree of optimism on the part of Cuadrilla Resourses, which if extended to other areas of the business would in themselves raise concerns about the companies safety and environmental policies.

In addition to the Lancashire field the company has obtained licenses for sites in Sussex, Kent and Surrey. There are thought to be reserves of shale gas suitable for extracting by fracking in Wales, Northern Ireland and Scotland as well as in England.


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Sunday, 15 January 2012

Protests against hydraulic fractionation across Bulgaria.

Protests took place across Bulgaria on Saturday 14 December 2012, against plans by the government to allow US oil and gas company Chevron to extract shale gas by hydraulic fractionation ('fracking') in the country. Protests took place in the capitol, Sophia, as well as in the Dobruzha region in the northeast, in the Black Sea ports of Varna and Burgas, and the provincial capitols of Plodiv and Pleven.

Protestors in Sophia on Saturday 14 January 2012.

Hydraulic fractionation, or fracking, is a process by which pressurized water and chemicals are forced into buried shale deposits in order to shock them into releasing gas and sometimes oil. The process has been linked to earthquakes, accused of polluting freshwater aquifers and using excessive water in dry countries.

Bulgaria is currently regarded as the poorest country in the European Union, and is more-or-less dependent on imported gas from Russia to satisfy its energy needs. The country is estimated to have between 300 billion and one trillion cubic meters of shale gas in two fields, one near Novi Pazar in the northeast of the country, and one offshore on the Black Sea Shelf. The Bulgarian government has recently signed a five-year deal with Chevron, allowing the company to explore the Novi Pazar field, with the potential to break the countries dependence on Russian gas, and bring jobs and investment to the country.

However environmental group Fracking Free Bulgaria has objected to the plans on the grounds that the area is home to freshwater aquifers that supply much of the Balkans, and is already prone to seismic activity (which may heighten the possibility of chemicals used in the process leaking into aquifers, and the pressure blasts triggering larger earthquakes), and that the local population has not been consulted about the deal. In addition to the street protests a Facebook group called We are against a Bulgarian Chernobyl - The extraction of Shale Gas has attracted over 50 000 members.

The protests culminated with the presentation of a petition to the Speaker of the Bulgarian Parliament, Tsetska Tsacheva, calling for a moratorium on the process, something that has happened in a number of states around the world, including France in the EU. Tsacheva is reported to have promised a parliamentary debate on a moratorium, though since Bulgaria has already signed a deal with Chevron, this might be hard to enforce without being forced to pay some form of compensation to the oil company.

Exploration companies Park Place Energy and TransAtlantic Petroleum are also apparently interested in extracting shale gas in Bulgaria. Both companies claim to already have licenses to develop shale gas fields in Bulgaria, though the Bulgarian Government has not confirmed this.

Monday, 26 December 2011

Oklahoma shaken by Earthquake on Christmas Day.

At 8.10 am local time (2.10 pm GMT) on the morning of 25 December 2011 the small town of Cromwell in Seminole County, Oklahoma, was shaken by a small Earthquake. The quake measured 3.3 on the Richter Scale, which is fairly small, but occurred at a depth of only 10.4 km, directly beneath the town, enough to give the town quite a jolt, though there are no reports of any injuries or serious damage.

Earthquake location map from the United States Geological Survey.

Oklahoma is a long way from any major tectonic boundaries, but it does have a number of fault systems, and small Earthquakes are not unusual. Up until 2009 Oklahoma averaged about 50 Earthquakes a year, but in each of the two years 2010 and 2011 Oklahoma suffered over 1000 quakes, which requires an explanation.

Map of the geological fault lines of Oklahoma, from the Bureau of Economic Geology at the University of Texas at Austin.

This is major increase in seismic activity over a short period of time, and requires an explanation. In the absence of any known natural phenomenon that could have caused this (such as the appearance of a volcano in central Oklahoma), many residents have started to question whether the state's hydrocarbon industry could be to blame. Oklahoma has long been a producer of both natural gas and oil, but as reserves have shrunk producers have increasingly turned to Hydraulic Fractionation (Fracking) as a means of maintaining production levels.

Fracking is a process by which water and chemicals are forced into buried strata in high pressure blasts in order to produce shock waves, which will hopefully cause the release of hydrocarbons. Shock waves in buried strata are, in layman's terms, Earthquakes, so an increase in Earthquakes in areas where Fracking is being practiced is not surprising. The Fracking industry have always maintained that their aim is to provoke quakes with magnitudes of less than 1.0 on the Richter Scale, but in Oklahoma, as in other places the practice has been linked with much larger quakes, often in excess of 3.0; which is more than a hundred times as large (the Richter Scale is logarithmic, 2.0 is ten times as large as 1.0, 3.0 is ten times as large as 2.0 and one hundred times as large as 1.0), something the industry disputes, refusing to accept responsibility for such large quakes without further evidence, even though they cannot offer an alternative explanation for the increase in quake activity.

The American National Academy of Sciences is currently looking into the subject, and is expected to produce a detailed report on Fracking and Earthquakes sometime in 2012, but in the meantime the Oklahoma Geological Survey commissioned a report from Austin Holland, a tectonics expert at the Department of Geosciences, University of Arizona, into the conetection between a fracking operation at the Eola Field in Garvin County, to the southwest of Seminole.

Holland came to the conclusion that 'The strong correlation in time and space as well as a reasonable fit to a physical model suggest that there is a possibility these earthquakes were induced by hydraulic-fracturing. However, the uncertainties in the data make it impossible to say with a high degree of certainty whether or not these earthquakes were triggered by natural means or by the nearby hydraulic-fracturing operation'. This has been widely reported in the press as 'uncertainties in the data make it impossible to say with a high degree of certainty whether or not these earthquakes were triggered by natural means or by the nearby hydraulic-fracturing operation', or even 'Seismologist Cannot Link Drilling To Oklahoma Earthquakes', which is a long way from what Holland actually reports.

Holland examines seven criteria which need to be met in order to establish that the quakes are the responsibility of the Fracking operation in Garvin County. Five of these can be met, and the remaining two cannot be answered either way given the evidence available when making the report, which had not been gathered with the specific intention of answering these questions.

1. Are these events the first known earthquakes of this character in the region?
Unknown. Oklahoma does not have a long history, and earthquake monitoring has never been a priority as the state has never suffered a seriously debilitating quake. Therefore it is impossible to say with confidence that quakes on this scale have never occurred, merely that they have never been recorded.

2. Is there a clear correlation between injection and seismicity?

Yes. There was a clear correlation in time and space between deep fracking operations at Eola Field and earthquakes, but not between shallow operations and any quakes.

3. Are the epicenters near wells (within 5 km)?

Yes. Nearly all the earthquakes have epicenters (the point on the surface directly above the centre of the quake) within 5 km of a well, and the majority much closer.

4. Do some earthquakes occur at or near injection depths?

Yes. Most of the earthquakes occur near injection depths.

5. If not, are there known geologic structures that may channel flow to sites of earthquakes?

Yes. There are numerous vertical block faults within the Eola Field, which have excellent potential for channeling flow.

6. Are changes in fluid pressure at well bottoms sufficient to encourage seismicity?

Yes. If this was not the case then hydraulic fractionation would not work in these rocks.

7. Are changer in fluid pressure at hypocentral locations sufficient to encourage seismicity?

Unknown. The study was conducted using data that was collected for other purposes; it would simply not be possible to say from this data if this criteria was correct.

Map from Holland's report showing the extent of the Eola Field (cross-hatched area), pre-existing geological faults (green lines), the site of the well where Hydraulic Fractionation is taking place (black hexagon), an the location and depth of known quakes that have taken place since fractionation began (coloured circles, key to depths bottom right).

Thus when Holland states that 'The strong correlation in time and space as well as a reasonable fit to a physical model suggest that there is a possibility these earthquakes were induced by hydraulic-fracturing. However, the uncertainties in the data make it impossible to say with a high degree of certainty whether or not these earthquakes were triggered by natural means or by the nearby hydraulic-fracturing operation' he means just that; he is saying that using the data available, which was not gathered for the purpose of this study, it is not possible to be 100% certain that the quakes are being caused by the fracking, but this is still quite likely. In legal terms the balance of probability is that fracking is causing earthquakes, but that this cannot be proven beyond all reasonable doubt. Unfortunately Holland states this with dry scientific reserve rather with a salesman's hyperbole, which has enabled a degree of (sometimes willful) misinterpretation.