Hypo-theses » geology

Coal Bed Methane

hypocentre — Tue, 06 Jul 2010 22:33:54 +0000

Keele University, where I work, has a plan to become self-sufficient in energy. This involves installing a variety of energy sources such as wind turbines, solar panels and ground source heat pumps, but one of the major projects that is currently underway in pilot form is the extraction of methane from the coal seams beneath campus. I was fortunate enough to be allowed to visit the drill site at the end of last week.

The first impression of the site is its relatively small size, about the size of a football pitch and how quiet it is. From 100 metres away the road noise from the M6 motorway is louder.

The drill rig is also smaller than I expected it to be and, as can be seen in the image, is actually mounted on the back of a truck. The drilling plan is shown schematically below [not to scale].

The ‘mother’ borehole (in blue in the diagram) is drilled to about 1000m depth using directional drilling in an ‘S’ shape, shallowing through the target coal seam, and then steeping downwards to form a sump. This is the current stage of the drilling.

The drill bit will next be withdrawn back up the hole to the level of the target seam (in this case the Great Row Coal) and a spur drilled along the the coal seam itself, slightly dipping upwards (in red on the diagram). Water then drains from the coal seam to the sump where it is pumped out. The draining of the water decreases pressure in the seam and stimulates the release of methane from the coal.

If this proves successful, and the mother bore is already showing promising signs of methane, then the next stage will be to drill a number of other bores through a variety of seams, extract the methane which will then be piped to the University’s boiler house.

Keele is blessed with several unmined coal seams below campus. The land on which the university was built was once owned by the Sneyd family who built their family seat, Keele Hall, here. Whilst making, and losing, a fortune from coal mining in North Staffordshire they had the common sense not to undermine their own house!

The other thing that we are interested in are the bottom hole temperatures. North Staffordshire coal mines were amongst the warmest in the country, and if, as we expect, the downhole temperatures are around 50-60°C then we also have the potential for geothermal energy as well.

Disclaimer: As always, this blogpost represents the views of myself only, and are not necessarily those of my employer.

Beech Caves

hypocentre — Sat, 19 Jun 2010 17:09:37 +0000

Now that teaching and exams have finished for another year, thoughts turn to the field. Whilst the likes of Geotripper and Dr Jerque get to visit some spectaclur and unspoilt places, my field work takes me to somewhere interesting but not quite as pretty. These are Beech Caves in Staffordshire.

The caves aren’t natural but the result of mining the Triassic Bromsgrove Sandstone (formerly the Keuper Sandstone) for building stone. The pillar and stall workings were begun possibly in 1633 for the construction of the nearby Trentham Hall. The Trentham records for August 31st 1633 note a Roger Low being paid 22 pence per score for carrying 130 foot of stone from Beech.

Trentham Hall 1686 : Image source – Lost Heritage

This was the first of several halls at Trentham, being rebuilt in 1690 and again in the 1830s, ultimately becoming one of the finest buildings in England. Unfortunately, pollution from the growing Potteries conurbation filled the lakes with sewage and the magnificent hall was abandoned and demolished in 1912. The gardens did remain and now the lakes have been cleaned and the gardens refurbished (well worth a visit) there are plans to rebuild the hall as a five star hotel.

Beech Caves still show the evidence of the hand-pick marks by the miners as they followed a layer of pale-coloured sandstone dipping gently down into the hillside. The thick overburden made mining rather than quarrying a more attractive proposition.

In more recent times the caves were probably used as a munition store in the second world war but lately they have been used for raves and other undesirable activities. The caves are now litter strewn and graffiti covered. The land owner and the local council now want to block off the entrances to stop the ne’er-do-wells from getting in. However, in doing so, they will bury an important piece of Staffordshire’s geological history. It would be a great shame if these historic pillar and stall workings were lost. Whilst understanding the landowner’s concerns for the site, it is hoped that some limited, secure access can be maintained for historians and geologists alike.

Reference: Middleton T, 1986. A survey of Beech Cave, Staffordshire. Bulletin of the Peak District Mines Historical Society, 9, 401-403

Shark!

hypocentre — Sun, 06 Jun 2010 23:06:48 +0000

On a field trip to the Peak District this weekend. He is a close up of some Lower Carboniferous shark dermal denticles.

Also some nice crinoid fragments.

Geology Teachers in England – An Endangered Species

hypocentre — Tue, 01 Jun 2010 22:46:30 +0000

If Geology Teachers were a species, then in England they would have just had their ‘Red List’ status upgraded from VU vulnerable to EN endangered – a high risk of extinction in the wild. There are only two universities where geology teachers are trained for the award of Postgraduate Certificate in Education (PGCE). Bath University had no geologists on their PGCE course last year and Keele University has just announced that its Geology PGCE course is to close this summer after 50 years of training the country’s geology school teachers. This now means that there is unlikely to be any further specialist geology teachers to be trained in England.

In a year that has seen major geological news stories, large earthquakes in Mexico, Haiti and Chile, the volcano at Eyjafjallajökull and the Gulf of Mexico oil spill amongst others, geology as a subject in English schools is slowly dying. The mining industry is coming out of recession, as we pass peak oil hydrocarbons become harder to find, in a world of diminishing water resources hydrogeology becomes increasingly important, with increasing populations it becomes crucial to better understand natural hazards such as earthquakes, volcanoes and landslides, alternative energy sources such as geothermal and coal bed methane are now serious contenders, and the construction industry is belatedly cottoning on to the need for a better understanding of the subsurface, geology as a subject in England is being slowly killed off.

To be fair, this has been coming for some years now, since the introduction of the national curriculum. The few bits of geology that are still taught in English schools are, in the main, now taught by chemistry teachers. I don’t want to disparage chemistry teachers but in general they don’t have the background knowledge in geology to allow them the confidence to teach the subject well. If the situations were reversed, and I had to teach chemistry, I’d give it my best shot but without that foundation in the subject I would struggle, and I certainly could not teach it with the enthusiasm that comes from really knowing one’s subject. The other significant education event was dropping the compulsion for English school children to study geography to the age of sixteen. At university level, we used to pick up a significant number of students who came to study geography, really didn’t get on with ‘human’ geography and the things that they thought were physical geography (earthquakes, volcanoes, etc.) they discovered were actually geology. These changes in school education has led to a downward spiral. School children are either no longer exposed to geology or are taught it by teachers who are not specialists in the subject. Fewer go on to study university and ultimately go on to geology teacher training. As specialist geology teachers retire from schools they are either replaced by non-specialists or the geology-oriented courses are closed. Student numbers decline further and the downwards spiral tightens. There are now so few specialist geology courses taught in schools now that there are very few teaching opportunities for geology PGCE students. The lack of career opportunities in geology teaching causes geology PGCE applications to drop. And the spiral tightens further.

What can be done to reverse this trend? It the cause has to be treated, not the symptoms. It is unrealistic to expect any university to run a loss making course, particularly in the current economic climate, when there is little demand from either potential students or future employment in schools. If geology is to extract itself from the downward spiral, first there needs to be recognition at a national level that geology is of critical strategic importance to the country and is under threat. Certain STEM (Science, Technology, Engineering and Medicine) subjects have a recognised ‘Vulnerable’ status. These subjects get increased funding. Physics, chemistry and chemical engineering are considered vulnerable subjects of strategic importance by the Higher Education Funding Council for England (HEFCE) but geology isn’t. It should be. It is important that geological institutions in the UK should lobby hard for geology’s strategic vulnerable status to be recognised. They also need to lobby for a proper recognition of the importance of geology as subject in its own right within the national curriculum. Only with geology taught by geologists in schools will the downward spiral into oblivion be broken. The oil revenue from the North Sea has netted various British governments an estimated one trillion dollars. They have wasted it all. If only a fraction of a percent of this revenue had been given back to the subject that found them the resources in the first place then we wouldn’t be in this mess.

Which brings be on to the oil and mining companies. They have largely sat back and let this happen. They might moan about a lack of suitable graduates to employ but they have failed to address the fundamental root problem. They might get persuaded to fund the odd PhD topic or a couple of places on an MSc course in an area that might benefit them in the short term but they have not really engaged with developing the next generation of geologists. Oil companies in particular have profits in the billions annually. If only for their own future, they really do need to help support the training of future geology teachers a lot more than they currently do* and start lobbying for geology as a subject in schools … whilst they still have a subject in the UK to lobby for.

Disclaimer: Although I am employed by Keele University, I have no direct connection with the Education Department that provides PGCE training or the Earth Science Education Unit (other than that the Earth Learning Ideas website is hosted on our geophysics server). As always, this post is written solely on behalf of myself and not the University. My concern is for the future of geology as a subject in England irrespective of where any teacher training may or may not be done.

* The UK offshore operators association (UKOOA) do support the Earth Science Education Unit at Keele (who produce the Earth Learning Ideas for school teachers).

Rock365 – The First Hundred Days

hypocentre — Sat, 10 Apr 2010 20:07:17 +0000

Some time around last Christmas I made the rash decision to attempt a photographic 365 project – to take a photograph every day of 2010. As a geologist, the natural theme was rocks, mineral and fossils, and so Rock365 was born. Well, I’ve just finished the first 100 days. To be honest I didn’t think that I’d get this far. I’ve pretty much run out of my own samples but fortunately Keele has been teaching geology for sixty years come this summer and I’ve got an excellent teaching collection to fall back on.

I’ve not been putting the images here on this blog (other than in the sidebar widget down on the right) for two reasons. The first is that I thought that they might clutter up this blog and get in the way of the other posts. The second is that by using posterous I can post images via a simple e-mail which might be easier for me when I’m away in the field.

If you haven’t been subscribing to my posterous blog (either directly or via Chris’ allgeo feed) then this is what you have been missing …

The images can also be found on flickr or on google maps.

View Rock365 in a larger map

Only 265 days to go …

Wenlock Edge

hypocentre — Mon, 22 Mar 2010 23:59:04 +0000

Two visits this weekend to Wenlock Edge, Shropshire with strongly contrasting weather (cold and wet on Saturday, warm and sunny on Sunday). This is Knowle Quarry at Presthope, the original GSSP of the Wenlock, and studied by Roderick Impey Murchison in his establishment of the Silurian System. Knowle Quarry is owned by the National Trust and open to the public but being a SSSI no collecting of material is allowed.

There are two distinct facies present, massive reef knolls and interbedded limestones and marls. The red colour in the photograph is below is iron staining on a strike-slip fault plane that cuts the reefs, the near horizontal slickenside lineations can be seen on the surface.

After studying the features here we moved on to the neighbouring Lea Quarry, which was active until recently. Note that the quarry is on private land and permission from the landowner must be given before entering. Here is the margin between the two main facies.

Here the recently quarried faces and the low sun (on the Sunday at least) led to some very successful fossil hunting. Note that I’m a geophysicist who was along on the trips as a van driver so I apologise in advance for any mis-identification.

Crinoid and brachiopod fragments

Ketophyllum

Favosites

Heliosites

Stromatoporoid

Illuminating Hadrian’s Wall

hypocentre — Mon, 15 Mar 2010 23:18:12 +0000

This weekend I have been up to Northumberland to witness the illumination of Hadrian’s Wall. This is the view eastwards from Vercovicium or Housesteads Roman Fort. A beacon was lit about every 250m along its length across Britain.

The geology angle is, of course, that the Roman’s used the geology as part of the defences, with Hadrian’s Wall running along the top of the escarpment produced by the outcrop of the Great Whin Sill. Below is Housesteads from Google Earth.

Using Gigapan and Photosynth in Geology Teaching

hypocentre — Fri, 22 Jan 2010 00:59:50 +0000

This week I presented some work in progress on the use of gigapan and photosynth to assist mobility impaired geology students at the “Overcoming Barriers to Learning in the Geosciences” meeting of the Geography, Earth and Environmental Sciences (GEES) subject centre of the Higher Education Academy (HEA).

The main aim of our MIS:TIQUE project (mobility impaired students : teaching in quite unsuitable environments) is to provide alternative technologies for mobility impaired students so that they can attain an equivalent learning experience to the able-bodied in geology fieldwork. Gigapan and photosynth allow us to mimic the observation patterns that we would like all students to use. This involves starting with an overview to develop hypotheses to what might be going on, moving in and around the outcrop to make more detailed observations and test the hypotheses, and then move back out again to revise the overview.

I’ve embedded the presentation below. Feel free to use any of the ideas but obviously if you use any of it please credit the source. If you have any questions, comments or feedback please use the blog comments. [Apologies for my powerpoint style - I tend to talk over images without using much text on the slides but this wouldn't make much sense in this context so I have added what I said to the images.]

igs_gees_overcoming_barriers

See more presentations by hypocentre | Upload your own PowerPoint presentations

OpenGeoscience

hypocentre — Tue, 01 Dec 2009 00:02:12 +0000

BGS Make-a-map

Well, it’s about time. The British Geological Survey has been lagging behind its US cousin for some time now. Like the USGS, the BGS is funded by the taxpayer but unlike the American version the data has always been hard to get hold of and expensive. Bits of data have become available slowly as the BGS has gone digital. The 1:625000 scale digital geology map was released through geoindex and the OneGeology global geological mapping portal and this year I’ve been making a lot of use of their on-line rock lexicon, but up until now the 1:50000 digital geology maps have only been available via a paywall to universities or in paper form for the great unwashed.

Today, the BGS released their OpenGeoscience portal, a free service for non-commercial private study, research and educational activities for viewing geological maps, downloading photographs and other information.

There are six OpenGeoscience sections. The Data section covers parts that we’ve had access to previously like the geoindex graphical front end to the BGS’s data holdings such as maps, boreholes, earthquakes and the like, the lexicon of terms used on BGS maps, their rock classification scheme and their database of mineral and rock samples. The education section also links to stuff we have had before – notably ‘Make-A-Map’ for creating basic geological maps of the British Isles. They also (somewhat bravely) provide a link to their new climate change poster which shows that climate change is nothing new and puts into context the current fluctuations with respect to those over geological time.

The maps section provides three ‘views’. The first, a ‘simple’ view allows a zoomable view down to street level with the 1:50000 geological map (where available – not Northern Ireland yet) as an overlay. The geology layer, the transparency of which is variable with a slider control, is a vast improvement on what was previously available to the general public. However, the street map is several years out of date and the satellite view is quite poor resolution. Their ‘intermediate’ view is actually the 1:625000 geology kml layer for Google Earth that has been available through OneGeology for some time and which I blogged about previously here back in August last year. The ‘advanced’ data allows users to down load the 1:625000 data in in ESRI© and MapInfo© formats and also view the 1:50000 data using their Web Map Service.

As an educator, however, the best part for me is GeoScenic, the browsable collection of the BGS’s photographs. I can see this being really useful for examples in lectures.

Finally, and really something quite interesting, is a downloadable version of BGS·SIGMAmobile, the BGS ‘digital field data capture system’ (geological field notebook connected to a database) designed to run on a rugged tablet PC with integrated GPS units. Effectively this is a heavily customised versions of ArcMap 9.2 and MS Access 2003 and is something I’m going to be trying out in the near future.

All in all, it is good to have everything together in one portal, but much is not new and still lags behind what is accessible for the US.

Extreme Gardening

hypocentre — Sun, 15 Nov 2009 23:36:21 +0000

This weekend I’ve been involved in a bit of geoconservation work a.k.a. extreme gardening. Working with the Staffordshire RIGS group, we were cleaning up a couple of outcrops along the Hamps and Manifold Geotrail at a site called Ladyside Wood (Location 19 on the map below). The parent body of Staffordshire RIGS, UKRIGS (UK Regionally Important Geological / Geomorphological Sites) has just changed its name to GeoconservationUK. Personally I think that this is a poor choice as the RIGS groups do so much more than geoconservation. I would have preferred GeodiversityUK which would have given a feel for the range of things that we do.

But anyway, back to the Manifold Valley …

Part of the Hamps and Manifold Geotrail - Ladyside Wood #19

The map shows that the Ladyside Wood locality should display the transition from the reef knoll facies of the Milldale Limestone (purple), through the bedded facies of the Milldale (dark blue) to the overlying bedded Ecton Limestones (pale blue). Unfortunately the sections have become somewhat overgrown.

Milldale Limestone section before geoconservation

Ecton Limestone section before geoconservation

Often in geoconservation we find that there is a certain tension between the geoconservationists who want to expose the outcrops and the bioconservationists who want to preserve certain plants. Before starting clearance on this section we consulted with the National Trust who own the land. Can you spot what was the only plant they asked us to leave? OK, I admit it is difficult from the photos but the answer is the yellowish shrub on the right of the lower image. The bizarre thing is that is a flowering red currant – a garden shrub and not even native to Britain. Apparently it looks pretty when it flowers!

Anyway, after five hours of pruning, scraping, sawing and scrubbing, we managed to get the outcrops returned to some of their former glory.

Milldale Limestone section after geoconservation

Ecton Limestone section after geoconservation

This is the first of what I hope to be many geoconservation sessions to be run by Staffordshire RIGS.