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Images of the Day


They say a picture paints a thousand words. Which can only be good news if you're a time-pressed academic such as myself. Image of the day (or week or month, depending on how often I'm able to post.) will post a single image that will, hopefully, say a thousand words about unconventional gas extraction in the UK.



Earthquakes and trains:

This image compares the vibrations from a passing train, measured at a distance of 150m, to a simulated earthquake occurring 2km below Cuadrilla's Balcombe drilling site (from the Bristol University Balcombe baseline study). We found that the train vibrations had similar amplitude to a magnitude 1.5 earthquake, equivalent to the second quake that lead to the shut down Cuadrilla's operations in Blackpool in 2011 (and a two-year moratorium).

Water stress, shale and other industries:

Several images this week. This images show "water risk" in the USA for a number of industries, as computed by the World Resources Institute. The more red the colour, the greater the water risk.

Firstly, oil and gas:

Followed by electricity generation:

 What about agriculture?

And the construction industry?

The food and beverage industries?

And the textile industries?

The conclusion? While shale gas does have the potential to use a lot of water, but the risk it poses is substantially smaller than many other existing industries.

Microseismic monitoring:

Microseismic monitoring technology allows geophysicists to map the fractures as they are created during the stimulation process. This image shows a map of the fractures created during stimulation at Cotton Valley (an early East-Texas tight gas play). This shows the extent of a typical stimulation zone - a few hundred meters either side of the injection point, and no more than 50m above the injection depth. The black triangles show the geophones used to collect this data.


Impact of shale on US prices and manufacturing:

What impact has US shale gas production had on natural gas prices? It's been pretty dramatic:


Until 2010 the gas prices in Europe and the USA were pretty similar, tracking each other up and down. Post 2010, the difference is startling!

Why does this matter? Well, we use gas for a lot of things, not just electricity generation. For example, natural gas is required as feedstock for many industrial processes, especially the manufacture of the petrochemicals and plastics that modern life, and even anti-fracking campaigners, require.

The cost of this feedstock is a major driver in the final cost of these products, and hence the viability of the industries that make and use them. The figure below shows the proportion of the total product cost that is dependent on feedstock and energy for a range of common plastics and petrochemicals:


So how has the USA shale gas boom affected manufacturing there? The figure below compares the cost of manufacturing ethylene in various world regions in 2005 and in 2012.


In 2005 it was very cheap to manufacture petrochemicals in the middle east, while everywhere else the price was moderate, but pretty similar whether you were in China, Europe or the USA. 

In 2012, the USA was as cheap as the middle east, while China and Western Europe have become substantially more expensive. Hence the moves towards "re-shoring" of manufacturing in the USA, while the same companies look to get out of Western Europe.

This is another reason why renewables and shale gas development are not enemies. Forget electricity generation, we need natural gas as a raw material for manufacturing. 


Shale gas, coal and carbon:

Shale gas, where it displaces coal in the electricity generation mix, presents a substantial reduction in CO2 emissions. These two images highlight the state of affairs in terms of global CO2 budgets. The first image shows CO2 emissions from fuel source and from country (in 2008). Clearly, Chinese and American coal are by far the biggest culprits. The second shows an estimate of the amount of CO2 embedded in fossil fuels as yet unburned. This presents us with a clear choice - if we are to continue burning fossil fuels, we should be choosing to burn gas.



Energy in the Third World -Renewables and Gas:

Imagine you had $10 billion to invest in providing electricity to people in the developing world who currently go without.

The lack of electricity in the developing world is a major issue. Almost 3 billion people burn twigs and dung to keep warm and heat their food. This causes indoor air pollution, which has been estimated to cost over 4 million lives per year. Electricity allows refrigeration to keep food from spoiling and rotting. Refrigeration is also vital to keep certain medicines in good condition. Electricity powers computers and phones that allow people in developing countries to connect to the world.

The Center for Global Development have worked out how far your $10 billion would go if you were to use renewables, or were to use gas, or some mix of the two. How many people could you connect to an electricity supply?

If $10 billion of your aid and development money is invested in renewables in the developing world, it will provide electricity to 20 million people. If that money is invested in gas-fired power, it will provide electricity to 90 million people. Bjorn Lomborg provides a neat summary of the issues at stake that I recommend reading. 


Onshore drilling in the UK:

Onshore drilling is not new to the UK. Approximately 2,000 wells have been drilled onshore in this country, mainly in the 1970s - 1990s. This map shows where they are, coloured by the year they were drilled (pre-1949 are cyan, 1950 - 1979 are yellow, 1980 - 1999 are (light) pink, and 2000 - 2013 are (dark) purple).


To download Google Earth .kml files for these locations, use the following links: pre-19491950-19791980-19992000-present.


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.


Hydraulic Fracture Heights:

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.

   

Manmade Earthquakes:



First up, an image from the 2013 Davies et al. paper on induced seismicity. The bar chart shows the magnitudes of earthquakes triggered by human activity in the subsurface. Many human activities can trigger earthquakes, including hydroelectric dam impoundment, geothermal energy, coal and mineral mining, waste fluid re-injection, conventional oil and gas reservoirs, and of course, hydraulic stimulation. These activities are represented by the different coloured blocks - hydraulic stimulation is the thin black boxes at M = 2 - 3 (2 earthquakes) and M = 3 - 4 (1 earthquake). You can see how this compares with other activities. In the words of Professor Davies himself at the Unconventional Gas Aberdeen conference this week, "in terms of earthquakes, shale gas doesn't even make it into the premier league".

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