Friday, 18 August 2017

In a jam: the impact of geology on the Stonehenge tunnel Andy Farrant

The mention of Stonehenge often conjures up visions of standing stones and druids, but more often than not traffic jams also spring to mind. As anybody who has driven along the A303 in summer will know, the road past Stonehenge is a regular bottleneck. Traffic flows regularly exceed capacity and impacts one of the most iconic sites in the UK. In 1995, Highways England put forward proposals for a cut-and-cover tunnel to bypass Stonehenge. This was rejected following protests about the impact on the archaeology. New plans for a 2.1 km tunnel were drawn up in 2002 with an estimated cost of £183 million — before the impact of geology was assessed.

Like many other major infrastructure schemes in southern England, the tunnel was scheduled to be excavated in Upper Cretaceous Chalk. To the uninitiated, Chalk may appear to be a relatively homogenous flinty white rock, but to a geologist or engineer it is anything but. Its composition varies a great deal, ranging from soft clay-rich chalk without flints to very hard nodular chalk with abundant flints. The Chalk is also a major aquifer, the name given to a permeable rock that contains groundwater, so tunnelling can be problematic, especially where faults or major flint bands occur or where there are soft, weak or weathered chalks.

Ground investigation

When ground investigations started at Stonehenge in 2001, the most relevant up to date BGS geological map was from 1903. This showed the whole route as being underlain by ‘Upper Chalk’, which is not much use for developing a ground model or predicting engineering properties of the chalk! Site investigation boreholes were drilled along the tunnel route to understand the geology before tunnelling. In the Chalk, identifying key features such as flint bands in borehole cores and sections is an essential first step in understanding the ground conditions. Correlating these markers helps identify geological structures such as faults and helps tunnellers to predict difficult ground conditions.

Initial logging of site investigation boreholes by Prof. Rory Mortimore (Chalk Rock Ltd) proved ‘normal’ white chalk with flint bands, but one borehole indicated the presence of an unusual deposit of phosphatic chalk. Further ground investigations recorded the thickest known phosphatic chalk deposits in England with several horizons of phosphatic chalks and hardgrounds separated by ‘normal’ white chalks with flint bands and marl seams.

Geological mapping

In 2003, BGS remapped the Salisbury 1:50,000 sheet including the area around Stonehenge as part of the BGS national geological mapping programme. The ‘Upper Chalk’ is now divided into four formations: the Lewes Nodular, Seaford, Newhaven and Culver Chalk formations. The geological mapping confirmed the presence of the phosphatic chalk channels and identified several faults and fold structures. The very weak sandy phosphates occur within the upper part of the Seaford Chalk Formation, and the channels are overlain by the Newhaven Chalk Formation. We were able map out the main axis of the phosphatic chalk channel which extends for almost 2 km southwest of Stonehenge. The mapping was assisted by the use of high resolution palaeontology provided by Mark Woods and Ian Wilkinson. More recent fieldwork earlier this year confirmed the spatial extent of the Newhaven Chalk infilling the channels. The data was used to construct a geological cross-section along the proposed tunnel route.
Map of the area around Stonehenge 

Impact of geology on the tunnel scheme

The discovery of these phosphatic chalks had a major impact on the proposed tunnel scheme. The weak sandy nature of the phosphatic chalk, and the identification of several zones of weathered or faulted chalk influenced the design of the proposed tunnel and the machinery required to excavate it. The possibility of radon gas from the potential radioactive minerals in the phosphatic chalks and the risk of groundwater contamination were other environmental considerations. Disposal of phosphate-rich tunnelling spoil also posed a problem as it was likely to impact local vegetation.

The nature of the geology and groundwater conditions led to construction costs to more than double from £183 million to an eye watering £470 million! On 20 July 2005 the tunnel scheme was withdrawn by the Government partly due to rising costs of construction.

New tunnel scheme

In January this year, the Transport Secretary, Chris Grayling announced a new proposal for the Stonehenge bypass including a 2.9 km tunnel to the south of the initial scheme at an estimated cost of £1.4 billon. The preferred route is to be announced this summer. BGS mapping suggests that this new tunnel will also intersect phosphatic chalk. Geology matters…

Further reading 

Details of the geology of the Stonehenge area based on the site investigations for the 2002 tunnel scheme and BGS mapping have just been published in the Proceedings of the Geologists' Association.

Andy Farrant is the regional geologist for SE England

Monday, 14 August 2017

Stable Isotope Mass Spectrometry User Group (SIMSUG) Meeting…by Jack Lacey

In July, the 14th Stable Isotope Mass Spectrometry User Group (SIMSUG) meeting was hosted by the Stable Isotope Facility at the British Geological Survey. SIMSUG brings together scientific users, engineers, manufacturers, and suppliers of mass spectrometry equipment to discuss new applications and developments in stable isotope research and analytical instrumentation. Although the meeting has been held annually in the past, the last SIMSUG was hosted six years ago in 2011 by Lancaster University Centre for Ecology and Hydrology – so about time for a catch up!

Over 80 delegates attended this year’s meeting representing many disciplines and affiliations, including UK- and EU-based universities, research institutes, academic journals, and mass spectrometry companies. The meeting kicked-off with a tour of the BGS, including the geological walkway and core stores, and the stable isotope, geochronology, inorganic and organic geochemistry facilities, highlighting the broad range of geoscience, health, and environmental research undertaken at the BGS.

Delegates of SIMSUG 2017
The meeting programme was diverse, with scientific talks and posters organised into overarching themes covering methodological advances and systems innovation, tracing terrestrial and marine palaeoenvironmental change, and palaeodietary studies. Dr Peter Wynn (Lancaster University) gave a keynote presentation discussing the relevance of subglacial methane generation in a warming world, and Dr Tamsin O’Connell (University of Cambridge) described the contribution isotope analyses have made to palaeodietary studies and the potential for future developments.

A conference dinner was held at the National Justice Museum where delegates were able to enjoy an informative and interactive tour of Nottingham’s historic courthouse and jail. Dinner was followed by a guided walk through the city.
Discussions continued over dinner at the
National Justice Museum

Congratulations to all PhD students who won prizes. The quality of the presentations and posters was very high indeed and all student presenters received commendation from the judges, Peter and Tamsin. The award for best overall presenter went to Benjamin Bell (University of Manchester), best talk to Hal Bradbury (University of Cambridge), and best poster to Kim Wood (SUERC). Well done everyone!

Thanks to our sponsors (Thermo Fisher, Elementar, Sercon, Elemtex, Isoanalytical, Goss Scientific, Elemental Microanalysis, QRA) and to the rest of the Stable Isotope Facility organising team. Catch up with #SIMSUG2017 on Twitter!

We hope to see everyone again at SIMSUG 2019, which will be hosted by the Life Sciences Mass Spectrometry Facility at the University of Bristol.

For more information on SIMSUG, please visit the group’s Facebook page.

Friday, 11 August 2017

Walk this way: the BGS through the eyes of a newbie... by Grace Davis

Grace Davis started work at the British Geological Survey in July 2017, in this weekly series she shares what she gets up to as part of the Comms team at the BGS...

Anyone need a tour guide? I’m getting to be quite well-versed in what happens where at the BGS, as (just like last week) we had tour group visiting us on Tuesday. This time our guests were a lovely group from the U3A – that’s the University of the Third Age. They held a science seminar in the local area and hosted part of it at our site in Keyworth. I joined the group in the afternoon to help show them around and, despite the torrential downpour we had to paddle through, they had a whale of a time! The rain didn’t even put them off doing the geological walk: armed with macs and maps they braved the outdoors to find out more about this interesting and beautiful part of the site.

The walkway can be found running through the Keyworth campus and is open to everyone. I first saw it on the day of my job interview; it stood out despite my mind being full of nerves and the fear that I’d worn the wrong shoes. My now-colleague Jo Thomas walked me along it, explaining that the paving stones were laid out to represent the different geological time periods – starting way back in the Precambrian period, some 2500 million years ago, and stretching forward to the Quaternary period. The stones are gorgeous mix of colours and textures, brought here from all over the UK. Alongside the paving stand various large rocks and boulders, set into the ground. There is also the large feature wall on the front of the James Hutton Building, commemorating the work of the eponymous 18th century geologist. The wall is a stylised representation of Siccar Point on the Berwickshire Coast, location of the notable Hutton's Unconformity.

If you’d like to come and see this remarkable walkway for yourself then please do! It’s generally open Monday to Friday from 9:00 am to 4:30 pm and you can pick up a free leaflet from Reception. To find out more about the walk visit our website here. And if you see me (with or without a tour group in tow), do stop and say hi!

The walk isn’t the only thing open to the public at BGS Keyworth; you can also visit our lovely shop which is full of jewellery, home-ware, books and more – all with a geological theme of course (an alarming portion of my pay check may well find its way there; even now I can hear the gemstone jewellery whispering my name…). You can also visit our free art exhibition, Impossible Views, hosted in partnership with QuarryLab, a North Notts organisation which supports local artists. Bringing this post full circle (it's almost like I plan this), one of the artists' work features some great sketches of Siccar Point, so be sure to check it out! The exhibition's run has been extended and will run at our Keyworth base until January 2018, open every Friday from 9:30 am until 4:30 pm.

Monday, 7 August 2017

Fishy Laura Hubbard

Weighing samples at BGS Keyworth
I’m Laura, a 3rd year Animal Science with Computer Science student at the University of Nottingham. During summer 2016 I undertook a project looking at heavy metal and bacterial contamination of fish sold in the UK, in collaboration with the Inorganic Geochemistry Team at BGS, Keyworth. Although this may not seem like the most exciting topic (you might think there are bigger fish to fry) we currently import 70% of our seafood. It is important to monitor these products for harmful substances to find out what we are really eating. The main focus of the project was to compare imported farmed fish from Asia with wild caught and EU farmed fish. We often see horror stories in the news about food from abroad containing all sorts of scary things. But is there any truth to this or is it a load of codswallop?

What contaminants should we be worried about?

Although it is widely known that higher trophic predatory fish, such as tuna, contain high levels of mercury, there has not been a lot of research into species lower down the food chain. As it is a potent neurotoxin it is important we do not consume too much. Mercury bioaccumulates in our tissues causing damage to the central nervous system, especially in infants and unborn babies. Other heavy metals such as lead and arsenic are similarly poisonous, and the presence of these would be an indication of the quality of the environments the fish were farmed in.

If any of the samples contain harmful bacteria there is a danger that they could cause illness when consumed. The poorly regulated use of antibiotics in fish farming and present in the environment through waste from human activities is also a concern. This could drive antibiotic resistance in bacteria and result in antibiotic residues being present in food due for consumption; growing levels of antibiotic resistance pose a threat to global health.

The method

First of all I set off to the supermarkets, re-usable bags in hand, to purchase an array of fish ranging from haddock to the river cobbler. Back in the lab after a lot of chopping, mashing, drying and grinding I had reduced the fillets to fishy powders. This was offish-ially very smelly work and I was definitely not the most popular around campus that week. I then headed to the Direct Mercury Analyser at BGS to quantify the amount of mercury present in each fish. The brilliant team at BGS Keyworth also carried out ICP-MS analysis to determine other elemental contaminants. Using molecular techniques I identified which fish contained pathogenic bacterial DNA. A simple validated test revealed if any of the fish contained antibiotic residues.

From L-R: Fish powders ready for analysis; Antibiotic residue detection in tilapia fish (fish 26-30)

The results

I did find fish on sale in the supermarkets that contained mercury levels above the UK legal limit, although the majority of the samples were below. Over half of the fish contained DNA from Salmonella species and two fish species contained Campylobacter DNA; both associated with food-borne illnesses in consumers. The worst offenders were the farmed fish while the wild caught fish contained less bacterial contamination. All of the fish farmed in China tested positive for antibiotic residues but so did all of the haddock, wild caught in the Atlantic Ocean (what a red herring!).

MSD Animal Health Connect Bursary Award

Accepting MSD Connect Bursary Award
I was lucky enough to be given the opportuna-ity to present my findings at the MSD Animal Health Headquarters in Milton Keynes (who part funded my work), along with student representatives from other UK Veterinary Schools. They fund projects at each of the UK Veterinary Schools every year and offer awards for the top three projects. We each gave a presentation, headed off for lunch and then a tour of their facilities at Milton Keynes while the MSD panel discussed and deliberated. Amazingly I received 1st plaice, which just goes to show any-fin is possible.


Thank you to everyone at BGS Keyworth for their help with this project, particularly Dr Andy Marriott, and for making me feel so welcome in the labs. I would also like to thank my University of Nottingham supervisor, Dr Tracey Coffey, for giving me this opportuna-ity. This work was funded by a BBSRC Research Experience Placement Award and MSD Animal Health.

Friday, 4 August 2017

Microscopes, Groundhogs and Tours: the BGS through the eyes of a Grace Davis

Did you know that SEM stands for ‘scanning electron microscopy’ which allows scientists to take an incredibly close look at the composition of materials in a various formats (such as rock chips, polished thin sections and liquids)? The information SEM gives us can contribute towards mineral identification, textural analysis, fault rock studies, and much more.

I did not know this, unsurprisingly, but now I do! And so do 12 young people from the London International Youth Science Forum who joined us this Tuesday for a tour of the BGS. As one of the newer members of staff, I had the chance to accompany the students on the tour, serving as part route-guide and part extra member! The students, a mixture of young adults from around the world, were a pleasure to have with us and really engaged with the talks given by BGS scientists such as Dr Jeremy Rushton in the SEM lab and Dr Mike Howe who showed us around the National Geological Repository (aka the Core Store). (And I didn’t lose a single student so I’m marking it down as a big success.) We look forward to seeing you again next year, LIYSF!

SEM in action!
This week I continued to help with monitoring our social media accounts; the BGS is pretty active on Facebook, Twitter and Instagram so there’s always something going on! Our social media posts come from a combination of communications staff ferreting out interesting pieces of info, and submissions from the many scientists working on projects across the BGS. One of my favourite submissions this week was from the team who have developed a new version of the BGS Groundhog Desktop software. To the uninitiated (which I was until three days ago) this might sound a bit odd – what’s a groundhog doing at a desktop anyway? What this actually is, is a rather interesting piece of software that allows users to easily (and in the comfort of their own home) explore digital versions of geological features such as cross-sections, borehole logs and geological map linework. It’s free to use and we have a great YouTube tutorial on how to get started with it.  

I’ll back on the blog again next Friday but, until then, if you haven’t read my previous posts on being a BGS new starter you can check them out here, here and here!

Wednesday, 2 August 2017

Touring America on the cheap – as told by a skint student! By Rob Smith

Rob Smith, a student at the University of Nottingham, recently completed a month of work experience at the BGS in Keyworth. Here he talks about experiencing a part of the world well beyond his usual reach...

Here is one for all you money savers… I have just completed a four-week tour of the North Fork Toutle River (NFTR) catchment system, in Washington State, USA. The aim of the tour was to aid my understanding in the influences of the eruption of Mount Saint Helens as well as the deposition of enormous levels of sediment onto the river plain, and the implications that followed.

I am sure many of you will know that Mount Saint Helens erupted in 1980, with the stratovolcano erupting laterally. This lateral eruption blew around 25km2 of ash northward, settling at least one metre thick and resulting in lahars through the NFTR valleys, destroying vegetation and clogging up the river system.

During the tour I was able to travel through time seeing the recovery of vegetation in the surrounding areas.  I investigated the types of vegetation and the stability of sediment, and the impact of the large retention structures put in place by the USGS, US army engineer corps and University of Portland in order to protect the sediment and reduce flooding in large settlements downstream.

As well as being very interesting to me (as this work will provide the basis of my dissertation thesis) the whole tour did not cost me a penny!

This is the magic of the digital and virtual reality technology used by the BGS today. Using GeoVisionary, ArcMap, Groundhog Desktop, HoloLens and other BGS virtual reality tools, I got to experience, analyse, and conclude various questions about the area. I saw these changes in a way that traditional 2D imagery cannot even begin to show, and can even be difficult to comprehend in reality. These systems allowed me to investigate the surrounding area remotely prior to the eruption as well as the result and recovery of the event.

My area of work involved monitoring various changes over time, observing vegetation and the changes following through from succession of new pioneer species, in addition to monitoring whether management strategies were having any of the effects they aimed to achieve. Further to this I was aiming to predict landslides in areas which may increase the river sediment load; identifying areas of high risk.

The work I did barely scratched the surface of what can be achieved by the various visualisation systems used by the BGS. With the help of the specialist teams at the BGS (3D Visualisation Systems and Remote Sensing) it is possible to produce detailed maps worldwide, some of which are inaccessible in the field, and have the tools and know-how to explore both the above and below ground, providing the basis for arange of exciting new research to be undertaken.

Fortunately, I do get to do the tour in reality in August where I can ground truth my results from the above virtual investigation! I would just like to thank Ricky, Bruce and Alessandro who made the virtual tour possible.

Wednesday, 26 July 2017

DeepCHALLA subsampling party at the Universiteit Heather Moorhouse

The DeepCHALLA sampling team.
DeepCHALLA is an International Continental Scientific Drilling Programme project investigating ~250,000 years of climate change and ecosystem dynamics in Equatorial East Africa, using lake sediment cores from Challa, a 92m crater lake on the flanks of Mount Kilamanjaro in Kenya/Tanzania. Dr Heather Moorhouse from Lancaster University details her trip to Gent, Belgium where subsampling of the cores was undertaken in order to gather the material ready for analyses of isotopes from bulk organic material and diatoms (algae with silica cell walls), jointly undertaken at Lancaster University and the Stable Isotope Facility, British Geological Survey.

In mid-June, amidst a continental heatwave, scientists across the globe from ten different research institutes, descended on the Department of Limnology in Gent, Belgium to collect subsamples of the drilled sediment cores which totalled ~214 m in length, retrieved from Lake Challa, Kenya/Tanzania earlier in the year. In total 9459 subsamples were collected, of which over 1000 samples were collected by yours truly. Luckily for us subsamplers, the laboratory where we spent our days had air conditioning and boasted a picturesque botanical garden next door; perfect for picnic lunch breaks in the sun.

The success of the sampling can be attributed to the hard-work undertaken by the members of the DeepCHALLA team who visited the National Lacustrine Core Facility (LacCore) in Minneapolis, USA just after the core had been retrieved. Here, the composition of the core was described and logged, and from this, the optimum depths at which to take the samples were meticulously determined, taking care to avoid turbidites (sediment deposits resulting from slope failures), cracks in the sediment and tephra layers; which are a fragmented material emitted from volcanic eruptions (unless of course you are a member of the team from the University of Cambridge who is investigating the nature of the tephra deposits in Challa). The excellent condition of the sediment cores and the well-preserved laminations of the sediment at Challa, caused by changes from diatom-rich deposits to darker organic material, made the subsampling preparation relatively straightforward and ultimately, is what makes this a model dataset to work on.

From L-R: Example of laminated sediment layers and a tephra layer (pinkish band) can be seen; Sediment core with a
I was amongst the subsamplers who had to extract the amount of sediment required for each analysis from a core section at a given depth. Care had to be taken not to contaminate the sample with material from other depths or layers, harder than it sounds especially when the sediment was crumbly. Different analyses required different sampling resolutions so a chain system was created to maintain a continuous workflow, with different people sectioning different cores and depths at the same time. Once all the samples had been taken from each core section, the holes in the core are infilled with foam to prevent collapsing and contamination of different sediment layers then repackaged and put back in cold storage. We quickly developed an efficient sampling system and our quick pace resulted in us finishing a day early (fantastic chance for sightseeing and sampling the local cuisine of beer (very strong, be warned!) and frites).
Not a bad commute home; Gent at night!

Huge thanks go to Dirk Verschuren, Thijs Van der Meeren, Yoeri Torsy and the rest of the team at the Universiteit Gent who put in the hard graft in organising this sampling event. I eagerly await our next project meeting to see how all the analyses and results are coming along. Now, to get started in the laboratory…

DeepCHALLA is live!

Monday, 24 July 2017

Gorillas and feathered dinosaurs... by John Stevenson

George the Gorilla or Gorilla-saurus.
Nottingham locals and regular visitors to Wollaton Hall are very familiar with George the Gorilla as being the star attraction for Wollaton Hall’s Natural History Gallery. George is so popular that he now has his own Twitter page @George_Gorilla. Although, his profile picture seems to have been hijacked by some Photoshop gremlins that have given him a dinosaur’s tail and chicken-like comb on his head.

George has been a feature of Wollaton Hall since 1926 so why give him a dinosaur makeover? There’s a rock and mineral gallery in Wollaton Hall, but no dinosaurs…

Ground shakers to feathered flyers
Mamenchisaurus fills Wollaton's Great Hall at about 23m long from head to tail,
but is taller than three double-decker buses when in this rearing posture.

Wollaton Hall is hosting the ‘Dinosaurs of China’ exhibition that brings to life the story of how dinosaurs evolved into the birds that live alongside us today. The new exhibition, which opened in July and runs until the end of October, features fossils that have never been seen outside of Asia.

The exhibition includes the best-preserved dinosaur fossils from anywhere in the world, not just the bones, but also soft parts including skin and feathers. Many of the species on show are new science discoveries that were only named in the last 20 years.

The exhibition is simple and uncluttered with easy-to-read panels with bite-sized chunks of information to guide you through the story. I loved the use of the packing cases as plinths to lift the smaller dinosaurs off the ground. 

Highlights of the exhibition include  the Gigantoraptor, which at four metres high and eight metres long is the largest feathered dinosaur ever found; double decker buses are about four metres by eleven metres.

‘Flying’ dinosaurs include the Microraptor, which had flight feathers on its four limbs for gliding towards its intended prey. Measuring about a metre in length, the Microraptor is the largest four-winged dinosaur ever discovered - longer than today’s eagle or albatross.

Sinornithosaurus; a 'fuzzy raptor',
about the size of a turkey.

'Jurassic Park got it wrong!'

Large and deadly dinosaurs aside, I was particularly blown away by the preservation of the feathers in the fossils. Sinornithosaurus is labelled as 'a 'fuzzy-raptor' that proves Velociraptor had feathers', where you can clearly see the tuft-like feather structure.

What happened next?

The Dinosaurs of China exhibit integrates well with the existing natural history collection of Wollaton Hall, where the evolutionary story continues and makes the bold statement 'Dinosaurs are not extinct; birds are dinosaurs!' We see some feathered dinosaurs and dinosaur eggs among Wollaton's collection of today's birds including a pelican, bird-of-paradise and red kite.

Sinraptor, not feathered, probably scaly and the size of a minibus.

Collect the evidence that connects birds with dinosaurs.

 Education resources

If you were in any doubt about the connection between bird and dinosaurs, you could fill in the Dinosaurs of China trail sheet, they are available free on entry.

Visiting schools

Schools can visit the exhibition for teacher-led sessions or the Hall's education team offer a wide range of facilitated sessions; from Mary Anning and her Fossils to Earth Science Dinosaur Day.

What about the rock and mineral gallery?

Jurassic Nottingham, the forthcoming geology 
exhibition theme for Wollalton Hall. 
The Mineral Gallery is currently closed, but having chatted to Adam Smith, the museum curator, a new gallery is in the planning stage, but sadly it couldn't be ready to coincide with the visiting dinosaurs. The new Mineral Gallery should be ready in 2018, but you should go and see the Dinosaurs of China before the end of October and return again next year, it's well worth it.

Friday, 21 July 2017

Learning about the living earth: the BGS through the eyes of a newbie... by Grace Davis

Seismogram images of the earthquake on 20/07/17
It’s the end of another busy week at the BGS, and an even busier Friday. On the night of Thursday the 20th, as I’m sure you know, an M 6.7 earthquake hit southwest Turkey and the Dodecanese islands, tragically causing two fatalities, many injuries, and structural damage to buildings. I first heard about it on the radio as I drove to work, and arrived prepared to help with any enquiries we might receive. Most of my morning was spent on Twitter and Facebook, updating people with the information we had and directing them to our earthquake pages if they wanted to know more about why things like this happen.

Taking a step back in time, Monday saw me attending another lunchtime lecture (I think I’m getting to be a familiar sight in the conference room: eagerly clutching my notepad and pen like an anxious child on the first day of school). This one was all about our Official Development Assistance programme. The programme and projects involved are still being developed but, from what I gathered at the lecture, it’s certainly shaping up to be a fascinating and innovative area of work for the BGS that will have truly global implications.

Projects like this were one of the things that drew me to the BGS originally, and continue to intrigue me now. I think that sometimes people believe geology is all about things that have already happened, stuff that is ancient history. Although that’s undeniably part of it, what I have come to realise more and more and is that so much of geology is about the living earth: the processes and changes that are happening in front of our eyes (even though some are far too slow for our eyes to perceive!).

A wonderful example of living geology is the work the BGS does on energy. And if you’re wondering what that work is, well I can’t put it better than the words on the front page of the BGS’ energy web section: “the BGS supports science that seeks to understand and maximise the recovery of dwindling fossil fuel reserves, as well as helping the development of renewable energy such as geothermal power.” This is science that affects us all! If you’d like find out more about this work, why not head over to our dedicated energy pages.

There won’t be a post from me next week as I’ll be on annual leave, jaunting around Berlin with my family (birthday wishes to my dad who probably doesn’t want me to mention his age on here). So it’s adieu from me for now!

Tuesday, 18 July 2017

Hominin Sites and Paleolakes Drilling Jonathan Dean

Jonathan Dean (now at Hull University), who worked as  Post Doctoral Research Assistant at the British Geological Survey until February, reports on the latest group meeting of the research project he is involved with while at the BGS...

The Chew Bahir project team.
The latest meeting of the Chew Bahir portion of the Hominin Sites and Paleolakes Drilling Project took place in Potsdam in June. Chew Bahir is a lake in southern Ethiopia that was 'drilled' in 2014 to retrieve cores of lake sediment. These extend from the lake bed down to 290 metres into the sediments. This sediment accumulated over the past 500,000 years ago. I presented the isotope data that we produced at the Stable Isotope Facility at the British Geological Survey. By looking at the ratio of one type of oxygen to another, and how this varies from the present day lake bed through the sediment cores at intervals down to 290 metres, we are able to reconstruct how the climate changed between wet and dry over the past half a million years.

Our colleagues on the project are from the UK, Ethiopia, Germany and the US. Some are busy working out how old each bit of the sediment core is, e.g. using radiocarbon dating at the top and dating volcanic ash layers towards the bottom. Others are looking at changes in the type of algae found down the sediment core, to look at changes in how fresh or salty the lake water was over time. Some are taking the reconstructed climate changes and relating them to changes in human history. We want to establish what the climate was like when our species, Homo sapiens, evolved and then spread out of Africa. Some people have suggested that when climate changes from more variable to more stable, that can lead to movements of populations, but we want to test that hypothesis.

 From L-R: Location of one of the more famous Potsdam conferences, where Churchill, Truman and Stalin decided how
 to divide up Germany at the end of the Second World War; the famous Bridge of Spies in Potsdam.
While in Potsdam we visited the famous Bridge of Spies (aka Glienicke Bridge) and the Potsdam Conference venue. The bridge across the Havel River in Germany connects Berlin with Potsdam. The bridge was completed in 1907, although major reconstruction was necessary after it was damaged during World War II. During the Cold War the bridge was used several times for the exchange of captured spies and thus became known as the Bridge of Spies (several films have used this location)... The Potsdam Conference was held at Cecilienhof, the home of Crown Prince Wilhelm, in Potsdam, between July and August 1945. The conference participants were the Soviet Union, the United Kingdom, and the United States (Stalin, Churchill/Attlee, Truman). The 3 powers met to decide how to administer the defeated Nazi Germany, which had agreed to unconditional surrender nine weeks earlier.