The trench runs across the crest of the ‘Malvern Axis’, a major monoclinal fold trending north-south through central England that brings up Precambrian (~677 Ma; Cryogenian) to the surface. The Malvern line separates the two Precambrian terranes of the Midlands Microcraton, Wrekin Terrane to the west and Charnian Terrane to the east, that forms the solid basement of England. These Precambrian igneous rocks are unconformably overlain by Middle Cambrian Malvern Quartzite, and then Upper Silurian (Pridoli) Raglan Mudstone, and Upper Carboniferous (Moscovian) Halesowen Fm. This sequence was folded and thrust during the Variscan Orogeny at the end of the Carboniferous into the north-south Malvern Axis. Extension during the Triassic produced normal faulting along the Malvern Line and deposition of Middle Triassic (Anisian) Bromsgrove Sandstone to the east in the Worcester Graben. All this is being exposed in just one 100m trench, albeit somewhat tectonically shortened.

Standing on the axis, this is the view to the east. In the trench, the light coloured material in the foreground is Precambrian Malvern Complex, succeeded by grey/green and grey Carboniferous, red Silurian muds and Triassic sands towards the car.

To the west, the white is Cambrian followed by Carboniferous and Silurian on the other side of the axis. Note that many of the lithological identifications are still tentative.

The section is still in the process of being created and is on private land, but should be stunning when finished.

Garnet Hornblende Garbenschiefer from Lukmanier, Switzerland.

Almost thirty years ago I was fortunate enough to undertake my undergraduate geological mapping work for my degree dissertation in the Passo del Lucomagno / Lukmanier Pass region of Ticino, Switzerland. I have already talked about some of this in Accretionary Wedge #27 “Important Geological Experiences” and Accretionary Wedge #11 “Field camp”.

Google Earth view of my undergraduate mapping area at Lukmanierpass.

The topography, quite naturally for the Alps, was fairly severe, the campsite where I was staying at Acquacalda was at 1800m, the top of the ridge to the south was 2600m, and I had to descend 100m from the campsite before starting to climb up the other side. When working on the southern ridge it would take a couple of hours to walk up to the base of the ridge. I would then eat my lunch early, leave my rucksack and, travelling light, start to work my way up the side of the ridge carrying just my mapcase, notebook and compass-clinometer. I would spend the rest of the day working upwards until about four in the afternoon and then rapidly descend back to the campsite, collecting my rucksack along the way.

The south ridge of my mapping area from the campsite at Acquacalda

After about three weeks, about halfway through my stay there, I was working up to the south ridge. I had already ditched the rucksack but collected a fair sized sample of high-grade gneiss. I was crossing a boulder field and noticed an interesting looking exposure up a steep face to my right. I put my notebook down on a rock, placed my map case on top of it, and my gneiss sample on that to stop it blowing away. I then headed up to the steep outcrop with my compass-clinometer thinking I could easily remember a couple of readings and rock details and return to record the information in my notebook. At the exposure I took a couple of structural readings and then noticed that the rock structure looked even more interesting up and to my left. I traversed across and took another three readings, committing all five to memory.

I then turn round to return to my notebook. To my horror all I could see was a large boulder field. Although I had a luminous yellow field notebook, I had placed a grey map case on that, and then a large rock on top of that. They were perfectly camouflaged. I descended to where I thought I had left them and still couldn’t see them. I started to hunt for them. After an hour a mild panic started to set in. Had I just lost three weeks work down to my own stupidity? Since I knew that they had to be in the boulder field somewhere, I decided that the only solution was to criss-cross the boulder field in a grid search.

After another two hours without success, time was beginning to run out. As I was mapping alone, I had an agreement with the two others I was camping with and who were mapping adjacent areas, to meet up at 5pm. In the case of one of us not being there at that time, the other two would go out to look for them in case something had happened to them. I was going to have to give up soon to make the rendezvous deadline. My map and notebook could be ruined by weather if I left them out, even if I returned to find them the following day.

I decided to do just another couple of passes. And there they were, right in front of me, I practically walked into them. I was so relieved. I realised I was only 10m from where I thought I left them in the first place. I went back to that point and yes, I could see them from that point once I knew where they were, but the camouflage had been excellent. It was time to go back. But not before I had recorded the details of the outcrop including the five structural readings that had been burnt into my memory over the past three hours.

So, I haven’t ultimately left stuff behind on this occasion, but there is a follow up to the story. After my degree, I went to Cardiff to do a Ph.D. and I told the metamorphic petrology lecturer about the wonderful metamorphic rocks at Lukmanierpass, including hornblende garbenschiefer and kyanite schists that were so shiny you couldn’t look at them in the sun without sunglasses. I showed him the box of my rock samples that I had collected there. He asked if he could hang on to them for a while and I agreed. With the passing of my Ph.D. I completely forgot that I had lent him the rock samples. I moved on to Keele, and he moved on from Cardiff. I don’t know what happened to those rocks, but I do wish I hadn’t left them behind.

I’m late for this one and most of my geology photo archive isn’t on this laptop, so I’m going to go with something that I have to hand. This image is one of my gigapans (in this case a matrix of 16 x 6 photographs stitched together). It shows the foreshore at West Angle Bay, Pembrokeshire, Wales. The view looks westwards towards Milford Haven and shows the Lower Carboniferous Limestone contorted by a series of Variscan thrust related folds. One of the thrust planes is seen in the left of the image, over-steepened by the folding. To the centre of the image are a pair of whaleback periclinal anticlines. The beds then steepen again to vertical on the right via a tight syncline.

But the beauty of a gigapan image is that one can dive in and view the detail like the slickenside lineations on the thrust plane or the writing on the buoy.

All three hundred deskcrop images can be found on my companion posterous blog and at my flickr site.

A google map with links to the geotagged images is embedded below.

View Rock365 in a larger map

Lockwood DeWitt at Outside the Interzone is hosting this month’s accretionary wedge where he asks “What is the most important geological experience you’ve had?”. The stress here is on the word important.

Picking the most important is incredibly difficult for me. I have been fortunate in my earlier career to have all sorts of important geological experiences, from climbing the summit of Mt Fuji in Japan to exploring the deepest wastes of the Atacama desert, from standing at the top of Monte Perdido in the Pyrenees to the bottom of the Black Canyon of the Gunnison in Colorado.

However, the most important for me has to be my undergraduate mapping in Lukmanierpass, Switzerland because it was important to me on so many different levels. I’ve already covered this way back in Accretionary Wedge 11, Field Camp, so I’ll try not to repeat myself too much.

The first part of the importance is because it was a turning point in my life, the point where I grew up. Up to that point I had had something of a sheltered upbringing. I had not travelled abroad except for a “De la Beche Club” (the student geology society at the Royal School of Mines) cycling geology field weekend in Northern France, and I certainly hadn’t been abroad alone. There were three of us sharing a large frame tent in Switzerland, but the car could only take two plus the tent, so I had to make my way there by train. The Swiss railway system is incredible and runs to the second. It was the first time that I saw proper mountains. The metre gauge train from Göschenen at the northern end of the Gotthard Tunnel climbing up to Andermatt is an experience in itself. Travelling alone across Europe gave me the confidence to go to so many other places since then.

(Note: I’ve converted these to black and white because the older colour photos have faded badly)

It was also the first time that I had done proper independent mapping. Prior to this our mapping training was done as buddy pairs but here I was on my own. We wouldn’t be allowed by health and safety regulations to do this today, which is a real shame because it was a wonderful experience. It was just me against the rock. I had to sort things out for myself. It took me about four weeks to work out why in one part of the area the bedding/cleavage relationship was telling me that the beds were upside-down where as I knew from the stratigraphy that they were the right-way up. It was a struggle, but I cracked it – myself.

The geology was incredible. I’ve never really seen anything like it before of since. The sediments trapped between the internal and external basement zones of the Alps exhibit one of the highest metamorphic gradients in the world with one unit going from amphibolite grade (shown above) to sub-phyllite in just a couple of kilometres. Some of the faces with white kyanite acted a mirrors in the bright sunlight. You couldn’t examine the mineral texture without sunglasses.

My last day in the field was my 20th birthday. After almost six weeks mapping, I had just one last valley to map. And, halfway up the valley I found a rock that I was not anticipating to find. This has taught me never to assume anything where mapping is involved and always check everything out. I had to work very hard to sort out that valley’s geology because I had a train booked home the following morning. I returned to camp absolutely exhausted but ultimately triumphant.

Google Earth view of my undergraduate mapping area, from the lake to the top of the ridge in the middle distance. The foreground ridge by the lake is Precambrian external zone basement gneiss and the middle distance ridge is Precambrian internal zone basement gneiss. Between them is a sliver of highly deformed and metamorphosed Mesozoic sedimentary cover rocks.

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.

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

Also some nice crinoid fragments.

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).