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European Shale Gas

Wednesday, October 5, 2011 3:04:31 PM

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The desirability of exploiting shale gas resources has been heavily discussed in the United States, notably in connection with the Marcellus Shale. Now is the turn to Europe. European shale gas resources are estimated to be enough to cover another 60 years of European gas demand. There are however environmental concerns in play. Although one may argue, that it means environmental progress when clean shale gas is replacing dirty coal as energy source, the fracking process usually used to extract the gas may pollute the groundwater, and the practice has in fact already been suspended or banned in some countries due to environmental and health safety concerns. Last June, for instance, environmental concerns led France to ban hydraulic fracturing.

A map published in an on line article in a Danish magazine for engineers (Ingeniøren) shows where the European shale gas is located. Although the article is in Danish, a map is a map, so I am sure it is worth for everybody to look at - http://ing.dk/artikel/122435-her-ligger-europas-skifergas - just note that yellow = potential shale gas reservoir, and green = shale gas exploration area.

While western Europe is reluctant because of the environmental concerns, Eastern Europe, and in particular Poland, is more eager, a.o. as a means to gain independence from Russian conventional gas supplies.

This week the European Parliament will devote a committee meeting to the issue of shale gas development.



In Danish:


See also my posts on Shale Gas in Europe, incl. Denmark and No to (Marcellus) Shale Gas in New York .

PS of 6 October 2011:
An inquiry in the UK found no evidence that the hydraulic fracturing process involved in shale gas extraction – known as ‘fracking’ - poses a direct risk to underground water aquifers provided the drilling well is constructed properly, and Shale gas drilling in the UK has been given the go-ahead by MPs.
http://www.parliament.uk/business/committees/committees-a-z/commons-select/energy-and-climate-change-committee/news/new-report-shale-gas/
(Thanks to “Hypocentre” for his comment.)



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Shale Gas in Europe, incl. Denmark

Thursday, August 12, 2010 7:34:45 AM

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GASH (Gas Shales in Europe) is the first European interdisciplinary shale gas research initiative. It started in 2009. The overall project goal is to predict shale gas formation and occurrence in time and space. GASH focuses on the potential gas shales of Europe, especially on the Alum Shale (Bornholm, Denmark), and the Posidonia and Carboniferous Shales in Germany.

On 11 August 2010 a scientific drilling project to investigate natural gas in shale rock was launched on the Danish island of Bornholm. The GFZ German Research Centre for Geosciences together with the Geological Survey of Denmark and Greenland (GEUS) will be performing a shallow drilling of 40 meters into the Alum Shale of the island within the research project GASH. These dense claystone packages from the Cambrian era are some 500 million years old and may contain natural gas.

The drilling on Bornholm is to improve the knowledge on this subject, by analysing the obtained cores with geological, geochemical, geophysical and geomechanical methods. To this end, the mobile laboratory "BugLab" of the GFZ will be transported to Bornholm.

The drilling will take about three days. In order to validate the results, a second core will be drilled close to the first bore hole, which will remain with the GEUS in Denmark. Finally, the drilling will be followed by geophysical examinations using 3-D seismics and water samples.



So far no shale gas is produced in Europe. Before any production there are still many challenges to be overcome in Europe such as land access and environmental issues, such as contamination of ground water. Costs per well are still higher than in the US, and mining regulations are tighter. As yet it remains unclear whether European shales can support commercial shale gas production.

Shale has low permeability, so gas production in commercial quantities requires fractures to provide permeability. This problem is usually “solved” by "hydraulic fracturing". The shale rock in which the gas is trapped is so tight that it has to be broken in order for the gas to escape. A combination of sand and water laced with chemicals — including benzene — is pumped into the well bore at high pressure, shattering the rock and opening millions of tiny fissures, enabling the shale gas to seep into the pipeline.

In 2008, a hydrologist found evidence of benzene contamination in a water well in Wyoming, in the vicinity of a large shale gas field. Critics of hydraulic fracturing suspect that the chemicals used in the process have somehow leaked into the groundwater supply.

In Denmark about 99% of all drinking water comes from groundwater, which makes any contamination of groundwater a critical issue.



In Danish:


In German:




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No to (Marcellus) Shale Gas in New York

Thursday, August 5, 2010 1:56:59 PM

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Shale gas is natural gas produced from shale. Shale gas has become an increasingly important source of natural gas in the United States over the past decade.

The Marcellus Shale is a black shale formation (Devonian) extending deep underground from Ohio and West Virginia northeast into Pennsylvania and southern New York. Although the Marcellus Shale is exposed at the ground surface in some locations in the northern Finger Lakes area, it is as deep as 7,000 feet (more than 2000 m) or more below the ground surface along the Pennsylvania border in the Delaware River valley. Drilling activity is expected to focus on areas where the Marcellus shale is deeper than 2,000 feet (ca. 600 m).



Geologists estimate that the entire Marcellus Shale formation contains between 168 trillion to 516 trillion cubic feet (1 trillion cubic feet is 28 316 846 592 cubic metres) speaking of natural gas throughout its entire extent.

The techniques used are a bit problematic as they include horizontal drilling (see diagram) and hydraulic fracturing, a drilling technique that involves blasting enormous quantities of water, sand and chemicals into deep shale rock under high pressure to free trapped gas. The fracturing is necessary because of the extremely low natural permeability of shale. Shale gas therefore tends to cost more to produce than gas from conventional wells, but on the other hand, this is often offset by the low risk of shale gas wells.



The New York State Senate has just approved at least a nine-month delay in issuing permits for this method of natural gas drilling, saying more study is needed to ensure it does not contaminate the state's water supply. Environmental groups have seized on the BP spill in the Gulf of Mexico and a series of recent accidents in states that already allow drilling to demand more regulation.

Drilling opponents cheer - Statoil and its partners Chesapeake, Talisman og Vertical Resources are less happy.





In Norwegian:
http://www.petro.no/modules/module_123/proxy.asp?i=14662&D=2&C=14

PS of 6 August 2010:
Of course I forgot to mention that “Rapid Uplift” had a great post a couple of weeks ago on the shale gas potential in India



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The Door to Hell is in Turkmenistan

Tuesday, July 6, 2010 8:44:36 AM

One of the circulating “top 10 meme” seems to be something like the world's 10 weirdest places, and here is one such place: the door to hell in Turmenistan.

In 1971, so the story goes, when Turkmenistan was part of the Soviet union, some geologists were conducting gas drilling in the Karakum desert, near the Derweze area, which is rich in natural gas. The ground beneath the drilling rig collapsed, and the equipment disappeared in a large hole with a diameter of about 50–100 m. To avoid poisonous gas discharge, it was decided to burn the gas. The geologists had hoped the fire would go out in a few days but it has been burning ever since. That is for nearly forty years by now, but the question is for how much longer. Turkmenistan plans to increase its production of natural gas. In April 2010, the President of Turkmenistan visited the site and ordered that the hole should be closed, or other measures be taken to limit its influence on the development of other natural gas fields in the area. (But HOW? - maybe a job for BP?)





On a positive note, a terrible lot of methane from this site has not been blown into the atmosphere as a greenhouse gas.

On the negative side, the gas might have served for better purposes.

The Karakum desert occupies about 70 percent, or 350,000 km², of the area of Turkmenistan.







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Pockmarks in Spitsbergen Fjords

Wednesday, September 9, 2009 9:05:14 AM

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In my latest post I mentioned the open access to the Norwegian Journal of Geology. In this post I shall concentrate on a paper in their latest issue (2009 Volume 89 Nr. 1 & 2) - Pockmarks in Spitsbergen fjords.

Pockmarks are concave, crater-like features on the seafloor, generally up to several hundreds of meters in diameter and tens of meters in relief. ’Mega pockmarks’ can have diameters of more than 1.5 km and depths exceeding 150 m. The formation of pockmarks is mostly caused by the seepage of thermogenic and biogenic gases and the release of pore water. (For a discussion on biogenic versus thermogenic gas see a.o http://www.gaschem.com/determ.html ).

Forwick et al. have studied and analysed pockmarks in five selected fjords on Spitsbergen. I find that figure 8 in their paper summarises their findings quite well, so I have allowed myself to reproduce it below:



In short the pockmarks in question developed during the past ca. 11,300 years (that means after the last ice age or in other words in the Holocene), as the result of seepage of thermogenic gas and porewater. Factors controlling the distribution of pockmarks in these subpolar fjords include 1) tectonic lineaments, 2) the lithological composition and lateral outcrop of bedrock, 3) the orientation of glacial lineations and 4) exceptionally rapid deposition of debris lobes related to glacial surges.

I find it important to notice that the authors do not regard the melting of permafrost as an important factor contributing to the formation of pockmarks in Spitsbergen fjords, and they also exclude up-drifting ice detaching from the sub-seafloor as an important factor for the formation of pockmarks in the study area.

To recapitulate with reference to the figure: in general the gas is thermogenic and originating from organic-rich bedrock (4 on figure) - with pockmarks where these rocks crop out. The gas may also seep upwards through faults - with pockmarks along tectonic lineaments. Other pockmarks occur as strings in grooves of glacial lineations. More randomly orientated pockmarks occur where porewater migrate up through debris lobes (1 on figure).

Reference:
Matthias Forwick, Nicole J. Baeten & Tore O. Vorren
Pockmarks in Spitsbergen fjords
Norwegian Journal of Geology, 2009 Volume 89 Nr. 1 & 2.

I find the paper interesting on the background of the present discussion of increased release of methane in the Arctic Sea due to global warming - also “marketed” as the methane time bomb.

Here are a couple of links to articles in the media on respectively methane coming from reserves of methane hydrate beneath the sea bed and methane coming from thawing permafrost:





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Environmental Risks Posed by Oil Activities Offshore Greenland

Monday, June 15, 2009 3:19:45 PM

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The National Environmental Research Institute of Denmark has released two reports on “a preliminary strategic environmental impact assessment of hydrocarbon activities” in the areas respectively west and east of northern Greenland. The background is that the Bureau of Minerals and Petroleum of the Greenland Home Rule wishes to open the Kanumas areas for invitations for tender for oil exploration and exploitation. The Kanumas areas include two large areas: Northwest and Northeast Greenland, north of 72°N. In response to these areas opening up for exploration and exploitation a program was initiated in 2007 to provide knowledge necessary to assess potential consequences of oil activities through a Strategic Environmental Assessment.

Kanumas is an acronym for the Kalaallit Nunaat Marine Seismic (KANUMAS) project. “Kalaallit Nunaat” is Greenlandish for "Land of the Greenlanders", i.e. greenland (also known as Kalaallisut).

The two reports are of more than 200 pages each and cover a wealth of information - too much for me to mention in one post. Fortunately the full reports in pdf can be downloaded via the links below.

The physical environment of the study area is briefly described with focus on oceanography and ice conditions. Sea ice and icebergs are present throughout the year, with the lowest concentrations in August and September. One of the most important physical features of the biological environment is the polynyas (ice-free or almost ice-free areas surrounded by sea ice). (I described polynyas here).

The environmentally most severe accident would be a large oil spill. This has the potential to impact the marine ecosystem on all levels. The recent oil and gas assessment by the Arctic Council working groups (AMAP 2007) concluded that the main issue of environmental concern for the marine Arctic environment is a large oil spill, which particularly in ice-covered waters represents a threat at the population and even species level. Furthermore, will the lack of adequate response methods in ice-covered waters and the remoteness and lack of infrastructure in most of the assessment area add to the severity of an oil spill. Accidental oil spills may occur either during drilling (blowouts) or from accidents when storing or transporting oil. Large oil spills are rare events today due to ever-improving technical solutions and Health, Safety & Environment Policies. However, the risk cannot be eliminated and in an area with the presence of sea ice and icebergs, the possibility of an accident will be elevated.

I may come back to some of the points in the two reports later. For now I will just show you a figure from the reports showing the ocean currents around Greenland. This figure is from report 719 covering the eastern part of the Kanumas (shown in yellow). A similar figure for the western part is found in report 720. Please notice the Greenland Sea Gyre south of Svalbard/Spitsbergen. I wrote more about gyres here and here.



• http://www.dmu.dk/Udgivelser/Faglige+rapporter/700-749/Abstracts/FR_719_GB.htm
• http://www.dmu.dk/Udgivelser/Faglige+rapporter/700-749/Abstracts/FR_720_GB.htm



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Large Arctic Energy Reserves

Saturday, May 30, 2009 8:27:13 AM

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The United States Geological Survey (USGS) has assessed the area north of the Arctic Circle and concluded that about 30% of the world's undiscovered gas, and 13% of its undiscovered oil, may be found north of the Arctic Circle. Undiscovered natural gas is three times more abundant than oil in the Arctic and is largely concentrated in Russia. Most of the oil is on the other hand located offshore Alaska. Advances in the technology of oil and gas recovery, as well as vanishing ice cover around the North Pole, make the Arctic an increasingly attractive region for energy.

Of the 6% of Earth’s surface encompassed by the Arctic Circle, one-third is above sea level and another third is in continental shelves beneath less than 500 m of water. The remainder consists of deep ocean basins historically covered by sea ice.

While global warming gradually melts away the sea ice in the Arctic Ocean, the oil and gas deposits buried in that inaccessible region are becoming a lot less theoretical to the five northern nations with claims to those riches, the World Wildlife Fund (WWF) is deeply worried over the development and says that Arctic governments and industry are still unprepared for oil spills. On occasion of the 20th anniversary of the Exxon Valdez on 24 March, WWF issued a report renewing its call for a time-out on new offshore oil development in the Arctic until technologies improve to ensure adequate clean-up of an oil spill.

• http://www.sciencemag.org/cgi/content/abstract/324/5931/1175
• http://blogs.discovermagazine.com/80beats/2009/05/29/in-the-arctic-oil-gas-lottery-russia-looks-like-a-big-winner/
• http://www.neurope.eu/articles/93749.php

In Norwegian:
• http://www.tu.no/nyheter/article212007.ece

In Swedish:
• http://www.sr.se/Ekot/artikel.asp?artikel=2866731



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